Of bodies and of mans soul to discover the immortality of reasonable souls : with two discourses, Of the powder of sympathy, and, Of the vegetation of plants / by Sir Kenelm Digby, Knight.

FIRST TREATISE: DECLARING THE NATURE and OPERATION OF BODIES.

CHAP. I.

A Preamble to the whole discourse: Concerning Notions in general.

IN delivering any Science, the clearest and smoothest Me∣thod, and most agreeable to Nature, is to begin with the * 1.1 consideration of those things that are most Common and obvious; and by the dissection of them, to descend by order∣ly degrees and S••epps (as they lye in the way) to the ex∣amination of the most Particular and remote ones. Now, in our present intended Survey of a Body, the first thing, which occurs to our Sense in the perusal of it, is its Quantity, bulk, or magnitude. And this seems to be conceiv'd by all Mankind so inseparable from a Body, as that, when a man would distinguish a Corporeal Substance from a Spiritual one (which is accounted indivisible), he naturally pitches on an apprehen∣sion of its having bulk, and being solid, tangible, and apt to make impression on our outward senses: according to that expression of Lucretius, who, studying Nature in a familiar and rational manner, tells us, Tangere enim & tangi, nisi C••rpus nulla potest res. And therfore, in our inquiry of Bodies, we will observe that plain Method which Nature teaches us; and begin with examining what Quantity is: as being their

first and primary affection) and that which makes the things we treat of be what we intend to signifie by the name of Body▪

But, because there is a great 〈◊〉〈◊〉 of Apprehensions framed by learned men of the nature of Quantity (though indeed no∣thing * 1.2 can be more plain and simple then it is in it self) I con∣ceive it will not be amiss, before we enter into the explication of it, to consider how the mystery of discoursing and expressing our Thoughts to one another by Words (a prerogative belong∣ing only to Man) is order'd and govern'd among us: that so we may avoyd those rocks, which many, and for the most part such as think they spin the finest threds, suffer shipwrack against in their subtilest discourses. The most dangerous of all which assuredly is, when they confound the true and real Natures of things, with the Conceptions they frame of them in their own minds. By which fundamental miscarriage of their reasoning, they fall into great errours and absurdities: and whatever they build on so ruinous a foundation proves but useless cobwebs or prodigious Chymaeras. 'Tis true, words serve to express things; but, if you observe the matter well, you will perceive they do so, onely according to the Pictures we make of them in our own thoughts, and not according as the Things are in their proper natures. Which is very reasonable it should be so, since the Soul, that gives the Names, has nothing of the things in her but these Notions, and knows not the Things otherwise then by these Notions: and therefore cannot give other Names, but such as must signifie the Things by me∣diation of these Notions. In the Things all that belongs to them is comprised under one entire Entity; but in Us there are fram'd as many several distinct formal Conceptions, as that one Thing shews it self to us with different faces: Every one of which conceptions seems to have for its object a di∣stinct Thing; because the Conception it self is as much se∣ver'd and distinguish'd from another Conception or Image, ari∣sing out of the very same Thing that begot this, as it can be from any image painted in the understanding by an absolutely other Thing.

It will not be amiss to illustrate this matter by some fami∣liar * 1.3 Example. Imagin I have an Apple in my hand; the same Fruit works different effects upon my several Senses: my Eye

tells me 'tis green or red; my Nose that it hath a mellow scent, my Taste that it is sweet; and my Hand that it is cold and weigh∣ty. My Senses, thus affected, send messengers to my Phantasie with news of the discoveries they have made: and there, all of them make them several and distinct pictures of what enters by their doors. So that my Reason (which discourses on what it finds in my phantasie) can consider greenness by it self, or mellowness, or sweetness, or coldness, or any other quality whatever, singly and alone by it self; without relation to any other that is painted in me by the same Apple: in which none of these have any distinction at all, but are one and the same Substance of the Apple, that makes various and different impressions on me, according to the various dispo∣sitions of my several Senses; as hereafter we shall explicate at large But, in my mind, every one of these Notions is a di∣stinct Picture by it self; and as much sever'd from any of the rest arising from the same apple, as it would be from any impression or image made in me by a Stone or any o∣ther substance whatever that, being entire in it self and cir∣cumscribed within its own circle, is absolutely sequestred from any communication with the other. So that, what is but one entire thing in it self, seems to be many distinct things in my understanding: wherby, if I be not very cautious, and in a manner, wrestle with the bent and inclination of my Un∣derstanding, which is apt to refer the distinct and com∣plete stamp it finds within it self, to a distinct and com∣plete original Character in the Thing, I shall be in dan∣ger before I am aware, to give actual Beings to the quanti∣ty, figure, colour, smel, tast, and other accidents of the Ap∣ple, (each of them distinct one from another, as also from the Substance which they clothe), because I find the notions of them really distinguish'd, as if they were different Entities in my mind. And from thence I may infer, there is no contra∣diction in nature to have the Accidents really sever'd from one another, and to have them actually subsist without their Substance▪ and such other mistaken subtilties, which arise out of our unwary conceiting that things are in their own Na∣tures, after the same fashion as we consider them in our Un∣derstanding.

And this course of the minds disguising and changing the impressions it receives from outward objects, into appearances quite * 1.4 differing from what the things are in their own real na∣tures, may be observ'd not only in multiplying Entities where in truth there is but one; but also, in a contrary man∣ner, by comprising several distinct Things under one single Notion: which, if afterwards it be reflected back upon the things themselvs, is the occasion of exceeding great errours, and entangles one in unsuperable difficulties. As for exam∣ple; Looking upon several Cubes or Dyce, wherof one is of gold, another of lead, a third of ivory, a fourth of wood, a fifth of glass, and what other matter you please: all these se∣veral things agree together in my Understanding, and are there comprehended under one single notion of a Cube; which (like a Painter, that were to designe them only in black and white) makes one figure that represents them all. Now, if removing my consideration from this impression which the se∣veral cubes make in my understanding, to the cubes them∣selvs, I shall unwarily suffer my self to pin this one notion upon every one of them, and accordingly conceive it to be re∣ally in them; it will of necessity fall out, by this misapplying of my intellectual notion to the real things, that I must allow Existence to other entities, which never had nor can have any in nature.

From this conception Plato's Idea's had their birth. For, finding in his understanding one Universal notion, that agreed exactly to every Individual of the same Species or Substance which imprinted that notion in him; and conceiving that the picture of any thing must have an exact correspondence with the thing it represents; and not considering that this was but an imperfect picture of the individual that made it: he thence conceiv'd, there was actually in every individual Sub∣stance one universal Nature running through all of that species, which made them be what they were. And then, considering that corporeity, quantity, and other accidents of Matter, could not agree with this universal subsistent Nature, he denyed all those of it; and so, abstracting from all materiality in his Idea's, and giving them a real and actual subsistence in nature, he made them like Angels, whoce essences and formal reasons were to be

the Essence and to give Existence to corporeal individuals; and so each Idea was embodied in every individual of its species. To which opinion (and upon the same grounds) Averroes lean'd, in the particular of mens Souls. Likewise Scotus, finding in his understanding an Universal notion springing from the impression that Individuals make in it, will have a like Universal in the thing it self; so determining Uni∣versals (to use his own language and terms) to be à parte rei, and expressing the distinction they have from the rest of the thing, by the terms of actu formaliter, sed non realiter: and therby makes every individual comprise an universal sub∣sistent nature in it. Which inconvenience other modern Phi∣losophers, seeking to avoid, will not alsow these Universals a real and actual subsistence, but lend them only a fictitious Being; so making them, as they call them, Eutia rationis. But herein again they suffer themselvs to be carried down the stream, before they are aware, by the understanding (which is apt to pin upon the objects the notions it finds within it self resulting from them); and consider an Unity in the things, which in∣deed is only in the Understanding.

Therfore one of our greatest cares in the guidance of our discourse, and a continual and sedulous caution therin, ought * 1.5 to be used in this particular; where every errour is a funda∣mental one, and leads into inextricable labyrinths, and where that which is all our level to keep us upright and even (our Understanding) is so apt, by reason of its own nature and manner of operation, to make us slide into mistaking and errour. And (to summ up in short what this discourse aims at) we must narrowly take heed, left, reflecting upon the notions we have in our mind, we afterwards pin those aiery superstru∣ctures upon the material things themselvs that begot them, or frame a new conception of the nature of any thing by the ne∣gotiation of our understanding, upon those impressions which it self makes in us; wheras we should acquiesce and be content with that natural and plain notion, which springs immediately and primarily from the thing it self: which when we do not, the more we seem to excel in subtilty, the further we go from reality and truth; like an Arrow which, being wrong levell'd at hand, falls widest when shot in the strongest bow.

Now, to come to another point that makes to our pre∣sent purpose. We may observe there are two sorts of lan∣guage * 1.6 to express our notions by. One belongs in gene∣ral to all mankind, and the simplest person, that can but apprehend and speak sense, is as much judg of it as the greatest Doctor in the Schools; and, in this, the words ex∣press the things properly and plainly, according to the na∣tural conceptions that all people agree in making of them. The other sort of language is circled in with narrower bounds, and understood only by those that, in a parti∣cular express manner, have been train'd up to it: and ma∣ny of the words which are proper to it have been, by the Au∣thors of it, translated and wrested from the general concep∣tions of the same words, by some metaphor, or similitude, or allusion, to serve their private turns. Without the first man∣ner of expressing our notions, mankind could not live in so∣ciety together, and converse with one another: wheras, the other has no further extent, then among such persons as have agreed together, to explicate and design among themselvs par∣ticular notions peculiar to their arts and affairs.

Of the first kind are those ten general heads, which Aristotle calls Predicaments: under which he (who was the most judicious orderer of notions and director of mens conceptions, that ever lived) hath comprised whatever has, or can have, a being in nature. For, when any object occurs to our thoughts, we either consider the essential and fundamental Being of it; or we refer it to some species of Quantity; or we discover some Qualities in it; or we per∣ceive that it Does, or Suffers somthing; or we conceive it in some determinate Place or Time, and the like: Of all which every man living, that injoys but the use of rea∣son, finds naturally within himself, at the very first naming of them, a plain, complete, and satisfying notion; which is the same, without any the least variation, in all mankind, unless it be in such as have, industriously, and by force, and with much labour, perplex'd and deprav'd those primary and sincere impressions, which nature had freely made in them.

Of the second sort are the particular words of art, by

which learned men use to express what they mean in Scien∣ces; and the names of Instruments, and of such things as be∣long to Trades, and the like: as a Sine, a Tangent, an Epicycle, a Deferent, an Axe, a Trowel, and such others; the intelli∣gence of which belongs not to the generality of man∣kind, but only to the Geometricians, Astronomers, Car∣penters, Masons, and such persons as converse familiarly and frequently with those things. To learn the true signifi∣cation of such words, we must consult with those that have the knowledge and practice of them: as, in like manner, to understand the other kind of plain language, we must ob∣serve how the words that compose it are apprehended, used, and applyed by mankind in general; and not receive into this examination the wrested or Metaphorical senses of any learned men, who seek oftentimes (beyond any ground in nature) to frame a general notion that may comprehend all the particular ones, which in any sense, proper or improper, may arise out of the use of one word.

And this is the cause of great errours in discourse; so great and important, as I cannot too much inculcate the caution * 1.7 requisite to the avoyding of this rock. Which that it may be the better apprehended, I will instance in one example of a most plain and easie conception, wherin all mankind natu∣rally agrees; how the wresting it, from its proper, genuine, and original signification, leads one into strange absurdi∣ties: and yet they pass for subtil speculations. The notion of being in a place is naturally the same in all men living. Ask any simple Artisan, Where such a man, such a house, such a tree, or such a thing is? and he will answer you in the very same manner as the learnedest Philosopher would doe. He'l tell you, the Man you ask for is in such a Church, sitting in such a Piew, and in such a Corner of it;) that the House you inquire after is in such a Street, and next to such two Build∣ings on each side of it;) that the Tree you would find out is in such a Forest, upon such a Hill, near such a Fountain, and by such a Bush; that the Wine you would drink of is in such a Cellar, in such a Part of it, and in such a Cask: In conclusion, no man living, that speaks naturally and freely out of the notion he finds clearly in his understanding, will give you

other answer to the question of, where a thing is, then such a one as plainly expresses his conceit of being in place to be no other, then bodies being environ'd and inclos'd by some one or several others, that are immediate to it; as the place of a liquour is the vessel that contains it, and the place of the vessel is such a part of the chamber or house that it rests on, together with the ambient Air, which has a share in making up the places of most things. And this being the answer, that every man whatever will readily give to this question; and every asker being fully satisfied with it: we may safely con∣clude, That all their notions and conceptions of being in a place are the same; and consequently, that it is the natural and true one.

But then, some others, considering that such conditions as these will not agree to other things, which they likewise conceit to be in a place (for they receive it as an axi∣ome from their sense, that whatever is, must be somwhere, and whatever is no where is not at all); they fall to casting about how they may frame some common notion, to compre∣hend all the several kinds of being in place, which they imagine in the things they discourse of. If there were no∣thing but Bodies to be rank'd by them in the Predicament of Place, then that description, I have already set down, would be allow'd by them as sufficient. But, since that Spirits and Spiritual things (as Angels, Rational Souls, Verities, Scien∣ces, Arts, and the like) have a being in Nature; and yet will not be comprised in such a kind of place as a Body is contain'd in; they rack their thoughts to speculate out some com∣mon notion of being in place, which may be common to these, as well as to Bodies; like a common accident agreeing to divers subjects. And so, in the end, they pitch on an Entity, which they call an Ubi: and they conceit the nature and formal reason of that to be, the ranking of any thing in a place, when that Entity is thereto affixed. And then they have no further difficulty, in setling an Angel, or any pure Spirit, or immaterial Essence, in a place as properly, and as completely, as if it were a Corporal Substance. 'Tis but assigning an Ubi to such a Spirit, and he is presently riveted to what place you please: And, by multiplying the Ubis,

any individual body, to which they are assign'd, is, at the same instant, in as many distant places, as they allot it different Ubis: And, if they assign the same Ubi to several bodies, so many several ones, as they assign it to, will be in one and the same place: And, not only many bodies in one place, but even a whole body in an indivisible, by a kind of Ubi that has a power to resume all the extended parts and inclose them in a point of place. All which prodigious conceits and impossibi∣lities in nature spring out of their mistake, in framing Me∣taphysical and abstracted conceptions; instead of contenting themselvs with those plain, easie, and primary notions, which Nature stamps alike in all men of common sense and under∣standing. As, who desires to be further instructed in this par∣ticular may perceive, if he take the pains to look over what Mr. White hath discours'd of Place, in the first of his Dialogues De Mundo. To which Book I shall from time to time (ac∣cording as I shall have occasion) refer my Reader, in those subjects the Author takes upon him to prove: being confident that his Metaphysical Demonstrations there are as firm, as any Mathematical ones, (for Metaphysical Demonstrations have in themselvs as much firmness, certainty, and evidence as they); and will appear as evident to whoever shall understand them throughly, and frame right conceptions of them: which (how plain soever they seem) is not the work of every pretender to learning.

CHAP. II. Of Quantity.

AMong those primary affections which occur in the per∣usal of a Body, Quantity (as I have observ'd in the * 1.8 precedent Chapter) is one, and, in a manner, the first and root of all the rest. Therfore (according to the caution we have been so prolix in giving, because it is of so main impor∣tance), if we aim at right understanding the true nature of it, we must examin what apprehension all kinds of people (that is, mankind in general) make of it. By which proceeding, we do not make the ignorant Multitude judg of that Learning, which grows out of the consideration of Quantity: but on∣ly

of the natural notion, which serves learned men for a basis and foundation to build Scientifical superstructures on. For, though Sciences be the works and structures of the under∣standing, govern'd and level'd by the wary and strict rules of most ingenuous Artificers; yet the ground on which they are rais'd are such plain notion of things as, naturally and with∣out any art, present themselvs to every mans apprehension: without which for matter to work upon, those artificial refle∣ctions would leave the understanding as unsatisfied;) as a Cook would the appetite, by a dish upon which he should have exer∣cised all his art in dressing it, but whose first substance were not meat of solid nutriment. 'Tis the course Market that must deliver him plain materials to imploy his cunning on: And, in like manner, 'tis the indisciplin'd Multitude that must fur∣nish learned men with natural apprehensions and notions to exercise their wits about. Which when they have, they may use and order and reflect upon them as they please: but they must first receive them in that plain and naked form, as mankind in general pictures them out in their imagina∣tions.

And therfore the first work of Scholars is, to learn of the People (Quem penes arbitrium est & jus & norma loquendi) what is the true meaning and signification of these primary names; and what notions they beget, in the generality of man∣kind, of the things they design. Of the Common People, then, we must enquire What Quantity; is and we shall soon be in∣formed, if we but consider what answer any sensible man will make on the sudden, to a question wherof that is the subject; for, such unstudied replies express sincerely the plain and na∣tural conceptions which they that make them have of the things they speak of. And this, of Quantity, is the plainest and the first that nature prints in us, of all the things we see, feel, and converse with; and that must serve for a ground to all our other inquiries and reflections: for which cause we must be sure not to receive it wrested or disguised from its own * 1.9 nature.

If then any one be asked, What Quantity there is in such a thing, or how great it is; he will presently in his understand∣ing compare it with some other thing (equally known by both

parties) that may serve for a measure to it: and then answer, That it is as big as it, or twice as big, or not half so big, or the like, in fine, that it is bigger or lesser then another thing, or e∣qual to it.

'Tis of main importance to have this point throughly and clearly understood; therfore it will not be amiss to turn it and view it a little more particularly. If thou ask what Quantity there is of such a parcel of Cloth, how much Wood in such a piece of Timber, how much Gold in such an Ingot, how much Wine in such a Vessel, how much Time was taken up in such an Action? he that is to give you an account of them measures them by ells, by feet, by inches, by pounds, by ounces, by gallons, by pints, by days, by hours, and the like; and then tells you, how many of those parts are in the whole that you inquire of. Which answer every man living will at the instant, without study, make to this question; and with it every man, that shall ask, will be fully appay'd and satisfied: so that 'tis most evident, it fully expresses the notions of them both, and of all mankind, in this particular.

Wherfore, when we consider that Quantity is nothing else, but the Extension of a thing; and that this Extension is exprest by a determinate number of lesser extensions of the same nature; (which lesser ones are sooner and more easily apprehended then greater, because we are first acquainted and conversant with such, and our understanding grasps, weighs and discerns such more steadily, and makes an exacter judgment of them;) and that such lesser ones are in the greater which they measure, as parts in a whole; and that the whole, by comprehending those parts, is a mere capacity to be divided into them; we con∣clude, That Quantity or Bigness is nothing else but Divisibility;) and that a thing is big, by having a capacity to be divided, or (which is the same) to have parts made of it.

This is yet more evident (if more may be) in Discrete Quan∣tity (that is, in Number) then in Continued Quantity, or Ex∣tension. For, if we consider any number whatever, we shall find the essence of it consists in a capacity of being resolv'd and divided into so many Unities, as are contain'd in it; which are the parts of it. And this species of Quantity, being simpler then the other, servs for a rule to determine it by: as we may

observe in the familiar answers to questions of Continued Quantity, which express by number the Content of it; as, when one delivers the Quantity of a piece of ground, by such a num∣ber of furlongs, acres, perches, or the like.

But we must take heed of conceiving, that those parts, which we consider to discern the nature of Quantity, are actually and * 1.10 really in the whole of any continued one that contains them. Ells, feet, inches, are no more real Entities in the whole that is measur'd by them, and makes impressions of such notions in our Understanding; then, in our former example, colour, fi∣gure, mellowness, tast, and the like, are several substances in the Apple, that affects our several Senses with such various impres∣sions. 'Tis but one whole, that may indeed be cut into so many several parts; but those parts are not really there, till by divi∣sion they are parceled out: and then, the whole (out of which they are made) ceases to be any longer; and the parts succeed in lieu of it, and are every one of them a new whole.

This truth is evident out of the very definition we have ga∣ther'd of Quantity. For, since it is Divisibility, that is, a bare capacity to division; it follows, that it is not yet divided: and consequently, that those parts are not yet in it, which may be made of it; for, division is the making two or more things of one.

But, because this is a very great controversie in Schools, and so important to be determin'd and setled, as, without doing so, we * 1.11 shal be liable to main errours in searching the nature and ope∣rations of Bodies; and that the whole progress of our discourse will be uncertain and wavering, if this principle and foundation be not firmly laid: we must apply our selvs to bring some more particular and immediate proof of the verity of this asser∣tion. Which we wil doe, by shewing the inconvenience, impos∣sibility, and contradiction, that the admittance of the other leads to. For if we allow actual parts to be distinguish'd in Quantity, it wil follow that 'tis composed of points or indi∣visibles, which we shall prove to be impossible.

The first wil appear thus: if Quantity were divided into all the parts into which 'tis divisible, it would be divided into in∣divisibles (for nothing divisible, and not divided, would re∣main in it); but it is distinguish'd into the same parts into which

it would be divided, if it were divided into all the parts into which 'tis divisible; therfore it is distinguish'd into indivisi∣bles. The major proposition is evident to any man that has eyes of understanding. The minor is the confession, or rather the position, of the adversary; when he says that all its parts are actually distinguished. The consequence cannot be calum∣niated, since indivisibles, whether they be separated or joyn'd, are still but indivisibles; though that which is composed of them be divisible. It must then be granted that all the parts, which are in Quantity, are indivisibles; which parts being actu∣ally in it, and the whole being composed of these parts only, it follows, that Quantity is composed and made of indivisibles.

If any should cavil at the supposition, and say, we stretch it further then they intend it, by taking all the parts to be distin∣guished: wheras they mean only that there are parts actually in Quantity, abstracting from all; by reason that all, in that mat∣ter, would infer an infinity, which, to be actually in any crea∣ted thing, they will allow impossible. Our answer will be, to represent to them how this is barely said, without any ground or colour of reason; merely to evade the inconvenience the argument drives them to. For, if any parts be actually di∣stinguish'd, why should not all be so? What prerogative have some that the others have not? And how came they by it? If they have their actual distinction, out of their nature of be∣ing parts▪ then all must enjoy it alike, and all be equally distin∣guished, as the supposition goes: and they must all be indivisi∣bles, as we have proved. Besides, to prevent the cavil upon the word all, we may change the expression of the Proposition into a negative: for, if they admit (as they do) that there is no part in Quantity but is distinguish'd as far as it may be distinguish'd; then the same conclusion follows with no less evidence; and all will prove indivisibles, as before.

But 'tis impossible that indivisibles should make Quantity, for if they should, it must be done either by a finite and deter∣minate * 1.12 number, or by an infinite multitude of them. If you say by a finite, let us take (for example) three indivisibles, and, by adding them together, let us suppose a line composed; whose extent being only longitude, 'tis the first and simplest species of Quantity; and therfore whatever is divisible into

parts must be at least a line. This line thus made cannot be conceiv'd to be divided into more parts▪ then three; since doing so you reduce it into the indivisibles that composed it But Euclide hath demonstratively proved beyond all cavil (in the Tenth Proposition of his Sixth Book of Elements), that any line whatever may be divided into whatever number of parts; so that, if this be a line, it must be divisible into an hun∣dred, or a thousand, a million of parts: which being impos∣sible in a line, divided into three parts only, wherof every one is incapable of further division: it is evident, that neither a line, nor any Quantity whatever, is composed or made of a determinate number of indivisibles.

And, since this capacity, of being divisible into infinite parts, is a property belonging to all extension (for Euclide's de∣monstration is universal); we must needs confess that 'tis the nature of indivisibles, when joyn'd together, to be drown'd in one another; for, otherwise, there would result a kind of extension out of them, which would not have that pro∣perty; contrary to what Euclide has demonstrated. And from hence it follows, that Quantity cannot be composed of an in∣finite multitude of such indivisibles: for, if this be the nature of indivisibles, though you put never so great a number of them together, they will still drown themselvs all in one indivisible point. For, what difference can their being infinite bring to them, of such force as to destroy their essence and property? If you but consider how the essential composition of any Multi∣tude whatever is made, by the continual addition of Unities, till that number arise; 'tis evident, in our case, that the infinity of indivisibles must also arise, out of the continued addition of still one indivisible to the indivisibles presupposed. Then, let us apprehend a finite number of indivisibles, which (according as we have proved) make no extension, but are all drowned in the first: and observing how the progress to an in∣finite multitude goes on, by the steps of one and one, added still to this presupposed number: we shal see that every in∣divisible added, and consequently the whole infinity, will be drown'd in the first number, as that was in the first indivi∣sible.

Which will be yet plainer, if we consider, that the nature of

extension requires one part be not in the same place, where the other is: then, if the extension be composed of indivisibles, let us take two points of place in which this extension is; and inquire, whether the indivisibles in each of these points be finite or infinite. If it be answer'd that they are finite, then the finite indivisibles in these two points make an exten∣sion, which we have proved impossible: But if they be said to be infinite, then infinite indivisibles are drown'd in one point; and consequently have not the force to make extension. Thus then it remains firmly establish'd, That Quantity is not compo∣sed of indivisibles (neither finite, nor infinite ones) and conse∣quently, That parts are not actually in it.

Yet, before we leave this point, though we have already * 1.13 been somewhat long about it, I conceive it will not be tedi∣ous, if we be yet a little longer; and bend our discourse to re∣move a difficulty, that even Sense it self seems to object to us. For, doth not our eye evidently inform us, there are fingers, hands, arms, legs, feet, toes, and variety of other parts in a Mans Body? These are actually in him, and seem to be distinct things in him; so evidently, that we cannot be perswaded, but that we see and f••l the distinction between them▪ for, every one of them has a particular power of actual working and doing what belongs to its nature; each finger is really there, the hand is different from the foot, the leg from the arm, and so of the rest. Are not these parts then actually and really in a mans body? And is not each of them as really distinguish'd from any other?

This appears at first sight to be an insuperable Objection; because of the confirmation and evidence that Sense seems to give it: But, looking nearly into the matter, we shall find that the difficulty arises, not from what Sense informs us of, but from our wrong applying the conditions of our notions, to the things that make impressions upon our Sense. Sense judges not which is a finger, which is a hand, or which is a foot. The notions agreeing to these words, as well as the words themselvs, are productions of the Understanding; which, con∣sidering several impressions made upon the Sense by the same thing, as it has a vertue and power to several operation, frames several notions of it: as, in our former example, it doth

of colour, figure, tast, and the like, in an Apple. For, as these are not different bodies or substances distinguish'd one from ano∣ther; but are the same one entire thing, working severally upon the Senses, and that accordingly makes these different pictures in the mind, which are there as much distinguish'd as if they were pictures of different substances: So, the parts consi∣der'd in Quantity are not divers things, but only a virtue or power to be divers things; which virtue, making several impressions upon the Senses, occasions several notions in the Understanding. And the Understanding is so much the more prone to conceive those parts as distinct things, by how much Quantity is nearer to be distinct things, then the Qualities of the Apple are. For, Quantity is a possibility to be made di∣stinct things by division; wheras the others are but a virtue to doe distinct things. And yet (as we have touch'd above) nothing can be more manifest, then that, if Quantity be Divisi∣bility (which is, a possibility that many things may be made of it), these parts are not yet divers things. So that, if (for exam∣ple) a rod be laid before us, and half of it be hid from our sight, and the other half appear; it is not one part or thing that shews it self, and another part or thing that doth 〈◊〉〈◊〉 shew it self: but it is the same rod or thing which shews it self accord∣ing to the possibility of being one new thing; but doth not shew it self according to the possibility of being the other of the two things it may be made by division. Which example, if it be well consider'd, will make it much more easily sink into us, that a hand, or eye, or foot, is not a distinct thing by it self; but that it is the man, according as he hath a certain virtue or power in him to distinct operations. For, if you sever any of these parts from the whole body, the hand can no more hold, nor the eye see, nor the foot walk; which are the powers that essentially constitute them to be what they are: and therefore they are no * 1.14 longer a hand, an eye, or a foot.

Now then, to come to the objection; let us examine how far Sense may be allow'd to be judge in this difficulty, and we shall find, that Sense cannot determine any one part in a body; For, if it could, it would precisely tel, where that part begins or ends: but, it being agreed on that it begins and ends in indivisibles, 'tis certain, that Sense cannot determine of them.

If then Sense cannot determine any one part; how shall it see that it is distinguish'd from all other parts? Again, considering that all that whereof Sense is capable is divisible, it still tells us that, in all it sees, there are more parts then one, and there∣fore it cannot discern nor inform us of any that is one alone, nor knows what it is to be one, for it never could discern it: but what is many is many ones, and cannot be known by that which knows not what it is to be one: and consequently Sense cannot tell us, that there are many. Wherefore 'tis evi∣dent, that we may not rely upon Sense for this question. And, as for Reason, she has already given her verdict.

So that nothing remains but to shew, why we talk as we do, in ordinary discourse, of many parts: and that what we say in that kind is true, notwithstanding the unity of the thing. Which will appear plainly, if we consider that our Understand∣ing hath a custome, for the better discerning of things, to im∣pose on a thing, as it is under one notion, the exclusion of it self as it is under other notions. And this is evident to all Scholars, when the mark of exclusion is expresly put; as when they speak of a white thing, adding the reduplication, as white; which excludes all other considerations of that thing besides the whiteness of it. But when it comes under some particular name of the thing, it may deceive those that are not cunning: though, indeed, most men discover it in such names as we call abstracted; as Humanity, Animality, and the like. But, it easily deceives when it comes in Concrete names; as it doth in the name of Part in general, or in the names of particu∣lar parts, as an hand, an eye, an inch, an ell, and others of the like nature: for, as you see that a part excludes both the notion of the whole, and of the remaining parts; so doth a hand, an eye, an ell, exclude all the rest of that thing, where∣of the hand is an hand, and the ell is an ell, and so forth. Now then, as every man sees evidently that it cannot be said, the Wall, as white, is Plaister or Stone: no more can it be said, that the Hand of a Man is his Foot; because the word hand sig∣nifies as much in it self, as if the man were taken, by redu∣plication, to be the man as he is hand, or as he hath the power of holding. So likewise, in the rod we spoke of before, it cannot be said that the part seen is the part unseen; because the part

seen signifies the rod, as it is a possibility to be made by divi∣sion such a thing as it appears to the sight. And thus 'tis clear, how the difficulty of this point▪ arises out of the wrong ap∣plying the conditions of our notions, and of names, to the ob∣jects and things which we know: whereof we gave warning in the beginning. * 1.15

After which there remains no more to be said of this sub∣ject, * 1.16 but to enumerate the several specieses of Quantity, ac∣cording to that division which Logitians, for more facilitie of discourse, have made of it. Namely, these six, Magnitude, Place, Motion, Time, Number, and Weight. Of which, the two first are Permanent, and lie still exposed to the pleasure of whoever has a mind to take a survey of them. Which he may doe by measuring what parts they are divisible into; how many ells, feet, inches a thing is long, broad, or deep; how great a place is, whether it be not biger or lesser then such another; and by such considerations as these; which all agree in this, that they express the essence of those two Specieses of Quantity, to consist in a Capacity of being divided into parts.

The two next, Motion and Time, though they be of a fleet∣ing propriety, yet 'tis evident that, in regard of their origi∣nal and essential nature, they are nothing else but a like divisi∣bility into parts; which is measured by passing over so great or so little distance, and by years, days, hours, minutes, and the like Number, we also see is of the same nature; for it is divisible in∣to so many determinate parts; and is measured by unities, or by lesser numbers so or so often contain'd in a proposed greater. And the like is evident of Weight, which is divisible into pounds, ounces, drams, or grains; and by them is measured. So that, looking over all the several specieses of Quantitie; 'tis evident, our definition of it is a true one, and expresses fully the essence of it, when we say it is Divisibilitie, or a Ca∣pacitie to be divided into parts: and that no other notion what∣ever, besides this, reaches the nature of of it.

CHAP. III. Of Rarity and Density.

I Intend in this Chapter to look, as far as I can, into the na∣ture and causes of the two first differences of Bodies; which * 1.17 follow out of Quantity, as it concurs with Substance to make a Body: for, the discovery of them, and of the various pro∣portions of them among themselves, will be a great and im∣portant step in the journey we are going. But the scarcity of our language is such, in subjects remov'd from ordinary conver∣sation, (though, in others, I think none is more copious or ex∣pressive) as affords us not apt words of our own to express significantly such notions as I must busie my self about in this discourse: therefore I will presume to borrow them from the Latine School, where there is much adoe about them. I would express the difference between bodies that, under the same measures and outward bulk, have a greater thinness and expansion, or thickness and solidity, one than another; which terms, (or any I can find in English) do not signifie fully those differences of Quantity which I intend here to declare: therefore I will do it under the names of Rarity and Density; the true meaning of which will appear by what we shall hereafter say.

'Tis evident to us, that there are different sorts of Bodies, of which though you take equal quantities in one regard, yet * 1.18 they will be unequal in another. Their magnitudes may be the same, but their weights will be different; or contrarywise, their weights being equal, their outward measures will not be so. Take a pinte of Air, and weigh it against a pinte of Wa∣ter, and you will see the ballance of the last go down amain; but if you drive out the Aire by filling the pinte with Lead, the other pinte in which the Water is, will rise again as fast: which if you pour out, and fill that pinte with Quicksilver, you will perceive the Lead to be much lighter; and again you will find a pinte of Gold heavier then so much Mercury. And in like manner, if you take away of the heavy bodies till they a∣gree in weight with the lighter, they wil take up & fill different proportions and parts of the measure that shall contain them.

But, whence this effect arises, is the difficulty we would

lay open. Our measures tel us their quantities are equal; and reason assures us there cannot be two bodies in one and the same place; therfore, when we see a pinte of one thing outweighs a pinte of another that is thiner, we must con∣clude there is more body compacted together in the heavy thing than in the light; for else, how could so little of a solid or dense thing be stretch'd out to take up so great room, as we see, in a basin of water that, being rarified into smoke or air, fills the whole chamber? and again, shrink back into so little room, as when it returns into water or is contracted into ice? But, how this comprehension of more body in equal room is effect∣ed, doth not a little trouble Philosophers.

To find a way that may carry us through these difficulties * 1.19 arising out of the Rarity and Density of Bodies, let us do as A∣stronomers, when they inquire the motions of the Spheres and Planets: they take all the Phenomena or several appearances of them to our eyes, and then attribute to them such Orbs, cour∣ses, and periods, as may square and fit with every one of them; and, by supposing them, they can exactly calculate all that will ever after happen to them in their motions. So, let us, take into our consideration the chief properties of rare and dense bodies; and then cast with our selvs to find out an hy∣pothesis or supposition (if it be possible) that may agree with them all.

First, it seems to us that dense bodies have their parts more close and compacted, than others have that are more rare and subtile. Secondly, they are more heavy than rare ones. A∣gain, the rare are more easily divided than the dense bodies: for water, oyl, milk, honey, and such like substances, will not only yield easily to any harder thing, than shall make its way through them, but they are so apt to division and to lose their continui∣ty, that their own weights will overcome and break it; wher∣as, in iron, gold, marble, and such dense bodies, a much greater weight and force is necessary to work that effect. And indeed, if we look wel into it, we shall find that the ra∣rer things are as divisible in a lesser Quantity, as the more dense are in a greater: and the same force will break the rarer thing into more and lesser parts, than it will an equal one that is more dense. Take a Stick of light wood, of such a big∣ness

that, being a foot long, you may break it with your hands; and another of the same bigness, but of a more heavy and compacted wood, and you shall not break it, though it be two foot long: and, with equal force, you may break a loaf of bread, into more and less parts, then a lump of lead that is of the same bigness. Which also will resist more to the division of Fire (the subtillest divider that is) then so much water will. For the little atomes of fire (which we shall discourse on here∣after) will pierce & cut out the water, almost into as little parts as themselves; and, mingling themselves with them, they will flie away together, and so convert the whole body of water into subtile smoke: whereas the same Agent, after long working upon lead, will bring it into no less parts then small grains of dust, which it calcines it into. And gold that is more dense then lead, resists peremptorily all the dividing power of fire; and will not at all be reduced into a calx or lime, by such operation as reduced lead into it.

So that, remembring how the nature of Quantity is Divisi∣bility; and considering that rare things are more divisible then dense ones; we must needs acknowledge, that the nature of Quantity is some way more perfectly in things that are Rare, then in those that are Dense. On the other side, more compact∣ed and dense things may haply seem to some to have more Quantity then those that are rare; and that is but shrunk toge∣ther, which may be stretch'd out and driven into much grea∣ter dimensions then the Quantity of rare things, taking the quantities of each equal in outward appearance. As gold may be beaten into much more and thiner leaf, then an equal bulk of silver or lead. A wax candle will burn longer with a small light, then a tallow candle of the same bigness; and consequently, be converted into a greater quantity of fire and air. Oyl will make much more flame then spirit of wine, that * 1.20 is far rarer then it.

These and such like considerations have much perplex'd Philosophers, and driven them into diverse thoughts to find out the reasons of them. Some, observing that the dividing of a body into little parts makes it less apt to descend, then when it is in greater, have believ'd the whole cause of lightness and rarity to be derived from division. As for example, they

find that lead cut into little pieces will not go down so fast in water, as when it is in bulk: and it may be reduced into so smal atomes, that it will, for some space, swim upon the water like dust of wood.

Which assumption is prov'd by the great Galileus: to whose excellent wit and admirable industry the world is beholding, not only for his wonderful discoveries made in the Heavens, but also for his acurate and learned declaring of those very things that lye under our feet. He (about the 90. page of his first Dialogue of Motion) clearly demonstrates, how any real medium must of necessity resist more the descent of a little piece of lead, or any other weighty matter, than it would a greater piece: and the resistance will be greater and greater, as the pieces are lesser and lesser. So, that as the pieces are made less, they will in the same medium sink the flower; and seem to have acquired a new nature of lightness by the diminution: not only of having less weight in them, than they had; as half an ounce is less than a whole ounce; but also of having in themselvs a less proportion of weight to their bulk, than they had; as a pound of Cork is, in regard of its magnitude, lighter than a pound of Lead. So as they conclude, that the thing, whose con∣tinued parts are the lesser, is in its own nature the lighter and the rarer: and other things, whose continued parts are greater, be heavier and denser.

But this discourse reaches not home: for, by it, the weight of any body being discovered, by the proportion it has to the me∣dium, * 1.21 in which it descends, it must ever suppose a body lighter than it self, in which it may sink and go to the bottome. Now, of that lighter body, I enquire, what makes it be so; and you must answer, by what you have concluded, that it is lighter then the other, because the parts of it are lesse and moreseverd from one another: for, if they be as close together, their division a∣vails them nothing; since things sticking fast together work as if they were but one, and so a pound of lead, though it be filed into small dust, if it be compacted hard together, will sink as fast as if it were one bulk.

Now then, allowingthe little parts to be seperated, I ask, what other body fills up the spaces, between those little parts of the medium in which your heavy body descends? For, if

the parts of water are more sever'd then the parts of lead, there must be some other substance to keep the parts of it asunder, let us suppose this to be air: and I ask, Whether an equal part of air be as heavy as so much water; or whether it be not? If you say it is; then the compound of water and air must be as heavy as lead; since their parts one with another are as much compacted as the parts of lead are. For, there is no diffe∣rence whether those bodies, whose little parts are compacted to∣gether, be of the same substance or, of divers, or whether the one be divided into smaller parts then the other or not (so they be of equal weights), in regard of making the whole equally hea∣vy: as you may experience, if you mingle pin-dust with a sand of equal weight, though it be beaten into far smaller divisions then the pin-dust, and put them in a bag together.

But if you say, that air is not so heavy as water; it must be, because every part of air hath again its parts more sever'd by some other body, then the parts of water are sever'd by air: And then, I make the same instance, of that body which severs the parts of air. And so at last (since there cannot actually be an infinite process of bodies, one lighter then another), you must come to one, whose little parts, filling the pores and spaces between the parts of the others, have no spaces in themselves to be fil'd up.

But, as soon as you acknowledge such a body to be lighter and rarer then all the rest, you contradict and destroy all you said before: For, by reason of its having no pores, it follows by your rule that, the little parts of it must be as heavy, if not heavier, then the little parts of the same bigness of that body whose pores it fills; and consequently, it is proved, by the ex∣perience we alledg'd of pin-dust mingled with sand, that the little parts of it cannot, by their mingling with the parts of the body in which it is immediately contain'd, make that lighter then it would be if these little parts were not mingled with it. Nor would both their parts mingled with the body which im∣mediately contains them, make that body lighter. And so, proceeding on in the same sort through all the mingled bodies till you come to the last that is immediately mingled with wa∣ter; you will make water nothing the lighter for being mingled with all these: and, by consequence, it should be as heavy and as dense as lead.

Now, that which deceiv'd the Authors of this opinion was, that they had not a right intelligence of the causes, which made little parts of bodies (naturally heavie) descend slowly, in re∣gard of the velocity of greater parts of the same bodies descen∣ding: the Doctrine of which we intend to deliver hereafter.

Others therfore, perceiving this rule to fall short, have in∣deavour'd * 1.22 to piece it out by the mixtion of Vacuitie among bo∣dies; believing, it is that which makes one rarer then another. Which mixtion they do not put always immediate to the main body they consider: but, if it have other rarer and lighter bodies mingled with it, they conceive this mixtion immediate only to the rarest or lightest. As for example, a Crystal be∣ing lighter, and consequently rarer, then a Diamond, they will not say there is more vacuity in a Crystal then in a Diamond; but that the pores of a Crystal are greater, and consequently there is more aire in a Crystal to fil the pores of it, then is in a Diamond: and the vacuities are in the aire, which abounding in a Crystal more then in a Diamond, makes that lighter and rarer then this, by the more vacuites that are in the greater Quantity of aire which is mingled with it.

But, against this suppsition, a powerful adversary is urged: for Aristotle (in his 4. Book of Physicks) hath demonstrated that there can be no motion in vacuity. 'Tis true, they indeavour to evade his demonstration (as not reaching home to their supposition,) by acknowledging it to be an evident one in such a vacuity as he there speaks of; which he supposed so great, that a body may swim in it as in an Ocean, and not touch or be near any other body; whereas, this opinion exclude all such vast inanity, & admit no vacuities but so little ones, as no body what∣ever can come to, but wil be biger than they, and, consequently, must on some side orother touch the corporal parts which those vacuities divide; for they are the separations of the least parts that are, or can be, actually divided from one another: which parts must of necessity touch one another, on some side, or else they could not hang together to compose one substance; and and therefore the dividing vacuities must be less then the divi∣ded parts. And thus, no body will ever be in danger of floating up and down without touching any thing: which is the diffi∣culty that Aristotle chiefly impugns.

I confess I should be very glad that this supposition might serve our turne, and save the Phenomena that appear among bo∣dies, * 1.23 through their variety of Rarity and Density. Which if it might be, then would I straight go on to the inquiring af∣ter what follow'd out of this ground; as Astronomers (to use our former similitude) calculate the future appearances of the Celestial bodies out of those motions and orbs they assign to the Heavens. For, as this apprehension of vacuity in bo∣dies is very easie and intelligible; so the other (which I con∣ceive to be the truth of the case) is exceedingly abstracted, and one of the most difficult points in all the Metaphysicks: and therefore I would (if it were possible) avoid touching upon it in this discourse, which I desire should be as plain and easie, and as much removed from, Scholastick terms, as may be.

But indeed, the inconveniences that follow out of this sup∣position of vacuities are so great, as it is impossible by any means to slide them over. As for example; let us borrow of Gallileus the proportion of weight between water and air. He * 1.24 shews us how the one is 400 times heavier then the other And Marinus Ghetaldus teaches us that gold is 19 times hea∣vier then water: so that gold must be 7600 times heavier then air. Now then, considering that nothing in a body can weigh, * 1.25 but the solid parts of it, it follows, that the proportion of the parts of gold, in a sphere of an inch Diameter, is, to the parts of the air of a like dimension, as 7600 is to one. Therfore, in air it self, the vacuities that are supposed in it will be, to the solid parts of it, in the same proportion as 7600 to one. Indeed, the proportion of difference shal be greater: for, even in gold many vacuities must be admitted; as appears by the heating of it, which shews that in every least part it is exceeding porous. But, according to this rate, without pressing the inconve∣nience any further, the air will, by this reckoning, appear to be like a net, whose holes & distances are to the lines and threds in the proportion of 7600 to one: and, so, would be ly∣able to have little parts of its body swim in those greater va∣cuities; contrary to what they strive to avoid. Which would be excedingly more, if we found, on the one side, any bodies heavier & denser then gold, & that were so solid as to exclude all vacuities; &, on the other side, should balance them withsuch

bodies as are lighter and rarer then air, as fire is, and as some say will have the aether to be. But, already the disproportion is so great and the vacuity so strangely exceeds the body in which it is, as were too great an absurdity to be admitted.

And besides it would destroy all motion of small bodies in the air; if it be true (as Aristotle hath demonstrated, in the fourth Book of his Physicks) that motion cannot be made but among bodies, and not in vacuo.

Again, if rarity were made by vacuity, rare bodies could not be gather'd together, without losing their rarity and becom∣ing dense. The contrary of which, we learn by constant experience: as when the Smith and Glassemender drive their white and fury fires, (as they term them); when aire pierces most in the sharp wind: and generally we see that more of the same kind of rare bodies, in less place, works more efficaci∣ously, according to the nature that results out of that degree of rarity. Which argues, that every little part is as rare as it was before (for else it would lose the vertue of working ac∣cording to the nature); but that, by their being crowded to∣gether, they exclude all other bodies that before mediated be∣tween the little parts of their main body; and so, more parts being gotten together, in the same place then formerly there were, they work more forcibly.

Thirdly, if such vacuities were the cause of rarity, it would follow that fluid bodies, being rarer then solid ones, would be of themselvs standing, like nets or cobwebs: wheras con∣trariwise, we see their natures are to run together, and to fill up every little creek and corner; which effect, following out of the very nature of the things themselves, needs must exclude vacu∣ities out of that nature.

And lastly, if it be true (as we have shew'd in the last Chap∣ter) that there are no actual parts in Quantity; it follows of ne∣cessity, that all Quantity must of it self be one; as Metaphysicks teach us: and then, no distance can be admitted between one Quantity and another.

And truely, if I understand Aristotle right, he hath per∣fectly demonstrated, that no vacuity is possible in nature; neither great nor little: and consequently, the whole machine, raised upon that supposition, must be ruinous. His argument is to this

purpose: What is nothing cannot have parts: but vacuum is nothing, (because, as the Adversaries conceive it, vacuum is the want of a corporeal substance in an inclosing body; within whose sides nothing is, whereas a certain body might be con∣tain'd within them; as if, in a pail or bowl of a gallon, there were neither milk, nor water, nor air, nor any other body, whatever): therefore vacuum cannot have parts. Yet those who admit it put it expresly for a Space; which essentially includes Parts: and thus they put two contradictories, nothing and parts, that is parts and no parts; or something and nothing in the same proposition. And this I conceive to be absolutely unavoidable.

For these reasons therfore, I must entreat my Readers fa∣vour, that he will allow me to touch upon Metaphysicks, a little * 1.26 more than I desire or intended: but it shall be no otherwise, then as is said of the Dogs by the River Nilus side; who being thirsty lap hastily of the water, only to serve their necessity, as they run along the shore. Thus then remembring how we determin'd that Quantity is Divisibility, it follows, that, if besides Quantity there be a Substance or Thing, which is di∣visible, that Thing if it be condistinguish'd from its Quantity or Divisibility, must of it self be indivisible; or (to speak more properly) it must be not divisible. Put then such Substance to be capable of the Quantity of the whole world or Universe; and consequently, you put it of it self indifferent to all, and to any part of Quantity: for in it, by reason of the negation of Divisibility, there is no variety of parts, wherof one should be the subject of one part of Quantity, or another of ano∣ther; or that one should be a capacity of more, another of ••ess.

This then being so, we have the ground of more or less Pro∣portion between Substance and Quantity: for, if the whole Quan∣tity of the Universe be put into it, the proportion of Quantity ••o the capacity of that substance, will be greater, than if but half ••hat quantity were imbibed in the same substance. And, because proportion changes on both sides, by the single change of only one side: it follows, that in the latter, the proportion of that Substance to its Quantity is greater; and that in the former, 'tis less, though the Substance in it self be indivisible.

What we have said thus in abstract will sink more easily in∣to us, if we apply it to some particular bodies here among us, in which we see a difference of Rarity and Density; as to air, wa∣ter, gold, or the like: and examine if the effects, that happen to them, do follow out of this disproportion between substance and Quantity. For example, let us conceive that all the quantity of the world were in one uniform substance; then the whole uni∣verse would be of one and the same degree of Rarity and Den∣sity: let that degree be the degree of water; it will then follow that, in what part soever there happens to be a change from this degree, that part will not have that proportion of quantity to its substance, which the quantity of the whole world had to the presupposed uniformsubstance. But, if it happens to have the degree of rarity which is in the air; it will then have more quantity in proportion to its substance, then would be due to it according to the presupposed proportion of the quantity of the universe to the aforesaid uniform substance: which in this case is as it were the standard to try all other proportions by. And contrariwise, if it happens to have the degree of Density which is found in earth or in gold; then it will have less quan∣tity in proportion to its substance, then would be due to it ac∣cording to the aforesaid proportion, or common standard.

Now to proceed from hence, with examining the effects which result out of this compounding of Quantity with sub∣stance; we may first consider, that the Definitions, which Ari∣stotle has given us of Rarity and Density, are the same we drive at. He tells us, that that body is rare whose quantity is more, and its substance less; that contrariwise, dense, where the sub∣stance is more and the quantity less. Now, if we look into the proprieties of the bodies we have named, or of any others; we shall see them all follow clearly out of these definitions. For first, that one is more diffused, another more compacted; such diffusion and compaction seem to be the very natures of Rari∣ty and Density, supposing them to be such as we have defined them to be; since substance is more diffused by having more parts, or by being in more parts; and is more compacted, by the contrary. And then, that rare bodies are more divisible then dense ones, you see is coincident into the same conceit with their diffusion and compaction. And from hence again it fol∣lows,

that they are more easily both divided into great, and, by the force of natural Agents, divisible into lesser parts: for both these (that is, facility of being divided, and easie divisibility into lesser parts) are contain'd in being more di∣visible; or in more enjoying the effect of Quantity, which is divisibility. From this again follows, that in rare bodies there is less resistance to the motion of another body through it, than in dense ones; and therefore a like force passes more easily through the one, than through the other. Again, rare bodies are more penetrative and active than dense ones: be∣cause being (by their overproportion of quantity) easily divi∣sible into small parts, they can run into every little pore, and so incorporate themselvs better into other bodies, than more dense ones can. Light bodies likewise must be rarer, because most divisible, if other circumstances concur equally.

Thus you see decypher'd to your hand the first division of bodies, flowing from Quantity as it is ordain'd to Substance for the composition of a Body: for, since the definition of a Bo∣dy is a thing which hath parts, and quantity is that by which it hath parts, and the first propriety of quantity is to be bigger or lesse, and consequently the first differences of having parts are to have bigger or lesse, more or fewer; what division of a Body can be more simple, more plain, or more immediate, than to divide it by its Quantity, as making it have bigger or less, more or fewer parts, in proportion to its Substance?

Neither can I justly be blamed for touching thus on Meta∣physicks, to explicate the nature of these two kinds of Bodies: for, Metaphysicks being the Science above Physicks, it belongs to her to declare the principles of Physicks; of which these we have now in hand are the very first step. But much more, if we consider that the composition of quantity with substance is purely Metaphysical, we must necessarily allow the inquiry in∣to the nature of Rarity and Density, to be wholly Metaphysical; since the essence of Rarity and Density stands in the proportion of quantity to substance: if we believe Aristole, (the greatest master that ever was, of finding out definitions and notions), and trust to the uncontroulable reasons we have brought in the precedent discourse.

This explication of Rarity and Density, by the composition * 1.27

of substance with quantity, may peradventure give little satisfa∣ction to such as are not used to raise their thoughts above Physical and natural speculations; who are apt to conceive there it no other composition or resolution, but such as our sen∣ses shew us in compounding and dividing bodies according to quantitive parts. Now, this obliges us to shew, that such a kind of composition and division as this must necessarily be al∣low'd of, even in that course of doctrine which seems most con∣trary to ours. To which purpose, let us suppose that the positi∣on of Democritus or of Epicurus is true; to wit, that the origi∣nal compositions of all bodies is out of very little ones of vari∣ous figures, all of them indivisible, not Mathematically, but Physically: and, that this infinite number of indivisibles floats in an immense ocean of vacuum or imaginary space. In this position, let any man, who conceives their grounds may be maintained, explicate, how one of these little bodies is mo∣ved. For, taking two parts of vacuum, in which this body suc∣cessively is; 'tis clear, that really, and not only in my under∣standing, 'tis a difference in the said body, to be now here now there: wherfore, when the body is gone thither, the notion of being here is no more in the body; and consequently, is divided from the body. And therfore, when the body was here, there was a composition between the body and its being here; which, seeing it cannot be betwixt two parts of Quantity, must of ne∣cessity be such a kind of composition, as we put between quan∣tity and substance. And certainly, let men wrack their brains never so much, they will never be able to shew how motion is made, without some such composition and division; upon what grounds soever they proceed.

And if then they tell us, that they understand not how there can be a divisibility between substance and quantity; we may reply, that to such a divisibility two things are required: first, that the Notions of Substance and Quantity be different; se∣condly, that one of them may be Chang'd without the other. As for the First, 'tis most evident, we make an absolute distin∣ction between their two notions: both when we say that Socrates was bigger a Man than a Boy; and when we conceive that milk or water while it boyles, or wine while it works, so as they run over the vessels they are in, are greater, and

possess more place, then when they were cool and quiet, and fill'd not the vessel to the brim. For, however witty explica∣tions may seem to evade, that the Same thing is now greater now lesser; yet it cannot be avoided but that ordinary men, who look not into Philosophy, both conceive it to be so, and in their familiar discourse express it so: which they could not do, if they had not different notions, of the Substance and of the Quantity of the thing they speak of. And, though we had no such evidences, the very names and definitions of them would put it beyond strife: all men calling substance a Thing; quantity, Bigness; and refering a Thing to Being (as who would say, that which is) but Bigness, to some other of like nature to which it is compar'd, as, that it is half as big, twice as big, or the like.

This then being unavoidable, that the Notions are distin∣guish'd; there remains no difficulty but only in the Second, namely, that the one may be Chang'd, and the other not: Which reason and demonstration convince, as we have shew'd. Wherfore, if any shall yet further reply, that they do not un∣derstand how such change is made; we shall answer, by asking them whether they know how the change of being sometimes here sometimes there is made by local motion in vacuum, with∣out a change in the body moved. Which question if they can∣not satisfie, they must either deny that there is any local motion in vacuum; or else admit a change in quantity without a change in substance: for this latter is as evidently true, as they suppose the former to be; though the manner how they are effected be alike obscure in both, and the reason of the obscurity the same in both.

With which we will conclude the present Chapter; adding onely this note: That, if all Physical things and natural chan∣ges proceed out of the constitution of rare and dense bodies, in this manner as we put them, (which the work we have in hand intends to shew); then, so manifold effects will so convince the truth of this doctrine we have declared, that there can remain no doubt of it: nor can there be any, of the divisibility of quantity from substance, without which this doctrine cannot consist. For, it cannot be understood, how there is a greater proportion of quantity than of sub∣stance,

or contrariwise, of substance then of quantity, if there be not a real divisibility between quantity and substance. And much less can it be conceiv'd, that the same thing hath at one time a greater proportion of Quantity, and at another time a less; if the greater or lesser proportion be not separable from it, that is, if there be not a divisibility betwixt it and sub∣stance, as well as there are different notions of them. Which to prove, by the proper principle, belonging to this matter, would require us to make a greater inrode into the very bowels of Metathysicks▪ and to take a larger circuit, then is fitting either for the subject, or for the intended brevity of this Treatise.

CHAP. IV. Of the four first Qualities: and of the four Elements.

THe subject of our discourse hitherto hath been three * 1.28 simple notions, Quantity, Rarity, and Density. Now it shall be to enquire, if, by compounding these with Gravity or Weight (which is one of the specieses of Quantity a∣bove mentioned, and of which I shall speak at large hereafter) we may beget any further qualities, and so produce the Four first Bodies, call'd Elements. Inimitation of Logitians, who, by com∣pounding such propositions as of themselves are evident to mans nature as soon as they are proposed, bring forth new knowledges: which threds they still entermix and weave to∣gether, till they grow into a fair piece. And thus the Sci∣ences they so much labour for, and that have so great an extent, result out of few and simple notions in their begin∣nings.

But, before we fall to mingling and comparing them toge∣ther, I think it will not be amiss to set down and determine, what kind of things we mean by rare, and what by dense; that, when the names are agreed on, we may slip into no errour by mistaking them. So then, though there be se∣veral considerations, in regard of which rarity and density may be differently attributed to bodies: yet, because mans discerning them, to be able to discourse accordingly of them, is the princpal respect for which their denominations are to be allotted them;

we may with reason call those things dense, wherein a man finds a sensible difficulty to part them, and those rare, where the re∣sistance is imperceptible.

And to these two notions of rarity and density we must allow a great latitude, far from consisting in an indivisible state; for, since rare faction makes a lesser body equal to a bigger; and all inequalitie betwixt two bodies, has the conditions of a Body; it follows, that the excess of one body over another consists of infinite parts, into which it might be divided; and, consequently, that what is rarified pas∣ses as many degrees, as the inequality or excess hath parts. And the same law being in condensations; both dense and rare things must be acknowledg'd capable of infinite variety and diversity of states, in regard of more and less in the same kind.

These things being premised; and calling to mind that 'tis the nature of density to make the parts of a dense thing com∣pact, * 1.29 and stick together, and be hardly divisible; and, on the contrary side, that 'tis the nature of rarity to diffuse and ex∣tend a rare thing, and prepare and approach it to division, according to the proportion of the degree of rarity which it has; and that weight abounds where there is excess of den∣sity, and is very little or none in excess of rarity: we may now begin in our imagination to put these Qualities into the scales one against another, to see what effects they produce in Bodies. And first, let us weigh Gravity against Density or stick∣ing together of parts: which sticking or compactedness, being natural to density, requires some excess of gravity in proportion to the density, or some other outward violence, to break it. If then in a dense body the gravity overcome the density, and make the parts of it break asunder; it will draw them down∣wards towards the center that gravity tends to, and never let them rest till they come thither, unless some impedi∣ment meet them by the way and stop their journey: so that such a body will, as near as it possibly can, lie in a perfect sphe∣rical figure in respect of the center; and the parts of it will be chang'd and alter'd, and thrust on any side that is the ready way thither, the force of gravity therefore working upon it, it will run as far as it meets with nothing to hinder it from

attaining this spherical superficies. Wherefore such bodies, for the most part, have no setled outside of their own; but receive their figure and limits from such lets as hinder them from at∣taining to that sphericalness they aim at.

Now Aristotle (whose definitions are in these matters gene∣rally receiv'd, as fully expressing the notions of mankind) tells us, and our own experience confirms it, that we use to call those things moist, which run in such sort as we have here set down: and that we term those things dry, which have a Con∣sistence within themselves, and which, to enjoy a determinate figure, do not require the stop or hinderance of another body to limit and circle them in; which will be the nature of those that have a greater proportion of density in respect of their gravity.

And thus, out of the comparison of density with weight, we have found two more qualities then we yet had met withall, namely wetness and dryness. For, though a body be dense, (which of its own nature, singly considered, would preserve the continuity of its parts, as making the body hardly divisible; whereby it would be dry) yet if the gravity that works up∣on it be, in proportion, greater then the density; it will sever the parts of it, and make them run to the center, and so be∣come fluide and moist: though not in the eminentest degree that may be of fluidity and moisture: because that, if the like over proportion of gravity happen in a rare body, it will there more powerfully work its effect, then it can in a dense body; because a rare body will more easily obey and yield to the gra∣vity that masters it, then a dense one will, and consequently, will be more fluide and moist then it.

Now on the other side, in weighing Rarity against Gravity, if it happen that the Rarity overcome the Gravity, then the * 1.30 gravity will not change the figure of a body so proportion'd; but what figure it has from its proper natural causes, the same will still remain with it: and consequently, such a body will have terms of its own, and not require an ambient body to limit and circle it in; which nature we call dry.

But, if the proportion of the gravity be the greater and overcome the rarity, then, by how much the rarity is greater, so much the more will the gravity force it to apply it self equal∣ly

and on all sides to the center; and such a body will the more easily receive its figure from another, and will be less able to consist of it self: which properties, we attribute to wetness or moisture. So that it appears, how the qualities of wet and dry, which first we found in things that were dense, are also com∣mon to that nature of bodies which we term rare.

And thus, by our first inquiry after what kind of bodies re∣sult out of the compounding of rarity and density with gravi∣ty, we discover four different sorts: some dense ones that are dry, and others likewise dense that are moist; then again, some rare ones that are likewise moist, and other rare ones that are dry.

But we must not rest here: let us proceed a little further, to * 1.31 search what other properties these four kinds of bodies will have; which we shall best discover, if we apply them severally to some other compounded bodie (of which nature are all those we converse with or see), and then consider the effects which these work upon it. To begin with that, which we said is so excessively Rare that gravity has no power over it. If we look on the multitude of little parts it may be divided into, whereof every one will subsist by it self (for we have already proved it dry, and then suppose them to be moved with force and strength against the body we apply them to: it must neces∣sarily follow that they will forcibily get into the porousness of it, and pass with violence between part and part, and of neces∣sity separate the parts of that thing one from another; as a knife or wedge doth a solid substance, by having their thinnest parts press'd into it. So that if, in the compounded thing, some parts be more weighty, others more light, (as of necessity there must be); the heaviest will all fall lowest, the lightest will fly upper∣most, and those which are of a mean nature between the two extremes will remain in the middle. In summe, by this action an extreme rare body upon a compounded one, all the parts of one kind that were in the compounded one will be gathered into one place; and those of divers kinds into divers places: which is the notion whereby Aristotle hath express'd the nature of heat; and is an effect which daily experience, in burning and boiling, teaches us to proceed from heat. And therefore we cannot doubt, but such extreme rare bodies are as well hot as dry.

On the other side, if a Dense thing be apply'd to a com∣pound, it will (because it is weighty) press it together: and, if that application be continu'd on all sides, so that no part of the body that is pressed be free from the siege of the dense bo∣dy that presses it, it will form it into a narrower room, and keep in the parts of it, not permitting any of them to slip out: So that what things soever it finds within its power to master, be they light or heavy, or of what contrary nature soever, it com∣presses them as much as it can, and draws them into a less compass, and holds them strongly together, making them stick fast to one another. Which effect Aristotle took for the pro∣per notion of cold; and therefore gave for definition of the nature of it, that it gathers things of divers natures: and expe∣rience shews us in freezing, and all great coolings, that this ef∣fect proceds from cold.

But, if we examine which of the two sorts of dense bodies, the fluide or the consistent, is most efficacious in this opera∣tion, * 1.32 we shall find that the less dense one is more capable of being apply'd round about the body it shall besiege; and there∣fore will stop closer every little hole, and more easily send subtile parts into every little vein of it; and by conse∣quence, shrink it up together and coagulate and constringe it more strongly, then a body can that is extremely dense; which, by reason of its great density and the stubbornness of its parts, cannot so easily bend and ply them to work this effect. And therefore, a body that is immoderately dense is colder then another that is so in excess; since cold is an active or work∣ing power, and that which is less dense excells in work∣ing.

On the contrary side, rare bodies being hot, because their subtile parts, environing a compounded body, will sink into the pores of it, and, to their power, separate its parts; it follows that those, wherein the gravity overcomes the rarity, are less hot then such others, as are in the extremity and highest excess of rarity: both, because the former are not able to pierce so little parts of the resisting dense body, as extreme rare ones are; and▪ likewise, because they more easily take ply by the obstacle of the solid ones they meet with, then these do.

So that out of this discourse we gather, that, of such bodies as differ precisely by the proportion of Rarity and Density, those which are extremely rare are in the excesse of heat, and are dry withall: that weighty rare bodies are extremely hu∣mid, and meanly hot: that fluide dense bodies are moist, though not in such excess as rare ones that are so; but are cold∣est of any: and lastly, that extreme dense bodies are less cold then fluide dense ones, and that they are dry.

But, whether the extreme dense bodies be more or less dry, * 1.33 then such as are extremely rare, remains yet to be decided. Which we shall easily do, if we but reflect that it is density which makes a thing hard to be divided, and rarity makes it easie: for, a facility to yeeld to division is nothing else, but a pliableness in the thing that is to be divided, wherby it easily receives the figure, which the thing that divides it doth cast it into. Now this plyablenss belongs more to rare then to dense things: and accordingly, we see fire more easily bend, by the concameration of an oven, then a stone can be reduced into due figure by hewing. And therfore, since dryness is a quality that makes those bodies, wherein it reigns, conserve themselves in their own figure and limits, and re∣sist the receiving of any from another body; it is manifest that those are driest wherein these effects are most seen, which is, in dense dodies: and consequently, excess of dryness must be allotted to them, to keep company with their moderate coldness.

Thus we see that the number of Elements assign'd by Ari∣stotle is truly and exactly determin'd by him: and that there * 1.34 can be neither more nor less of them; and their qualities are rightly allotted to them. Which to settle more firmly in our minds, it will not be mis-spent time to sum up in short the effect of what we have hitherto said to bring us to this Con∣clusion. First, we shew'd that a body is made and constituted a Body, by Quantity. Next, that the first division of Bodies is into Rare and Dense ones; as differing only by having more & less Quantity. And lastly, that the conjunction of Gravity with these two breeds two other sorts of combinations; each of which is also twofold: the first sort, concerning Rarity, out of which arises one extremely hot and moderately dry, and an∣other

extremely humide and moderately hot; the second sort, con∣cerning Density, out of which is produced one that is extremely cold and moderately wet, and another extremely dry and moderate∣ly cold. And these are the combinations whereby are constitu∣ted, Fire, Air, Water, and Earth.

So that we have thus the proper notions of the Four Ele∣ments; and both them and their qualities driven up and re∣solv'd into their most simple Principles: which are the noti∣ons of Quantity, and of the two most simple differences of quantitive things, Rarity and Density. Beyond which mans wit cannot penetrate; nor can his wishes aim at more in this particular: seeing he has attain'd to the knowledge of what they are, and of what makes them be so, and that it is impossi∣ble they should be otherwise; and this, by the most simple and first principles which enter into the composition of their na∣ture. Out of which it is evident, these Four bodies are Ele∣ments: since they cannot be resolv'd into any others, by way of physicall composition; themselves being constituted by the most simple Differences of a Body. And again, all other bodies whatever must of necessity be resolv'd into them, for the same reason; because no bodies can be exempt from the First deffe∣rences of a Body. Since then, we mean by the name of an Ele∣ment, a Body not composed of any former bodies, and of which all other bodies are composed; we may rest satisfied that these are rightly so named.

But, whether every one of these four Elements, compre∣hend under its name one only lowest Species or mady, (as, * 1.35 whether there be one only Species of fire, or several; and the like of the rest;) we intend not here to determine. Yet we note, that there is a great latitude in every kind; since Rarity and Density (as we have said before) are as divisible as Quan∣tity. Which Latitudes, in the bodies we converse with, are so limited that, What makes it self and other things be seen (as being accompanied by light) is called Fire: What admits the illuminative action of fire, and is not seen, is called Air: What admits the same action, and is seen (in the rank of Elements) is called Water: And what, through the density of it, admits not that action, but absolutely reflects it, is called Earth.

And, out of all we said of these four Elements, it is mani∣fest

there cannot be a fifth: as is to be seen at large in every Aristotelian Philosopher that writes of this matter. I am not ignorant that there are sundry objections used to be made, both against these notions of the First Qualities, and against the divi∣sion of the Elements: but because they and their solotions are to be found, in every ordinary Philosopher, and not of any great difficulty, and that the handling them is too particular for the design of this discourse, and would make it too prolix; I refer the Reader to seek them, for his satisfaction, in those Au∣thors that treat Physick professedly, and have deliver'd a com∣pleat body of Phylosophy,

And I will end this Chapter with advertising him (lest I should be misunderstood) that though my disquisition here has pitch'd on the four bodies of Fire, Air, Water, and Earth; yet it is not my intention to affirme that those which we ordinary call so, and fall daily within our use, are such as I have here express'd them: or that these Phlosophicall ones (which arise purely out of the combination of the first qua∣lities) have their residence or consistence in great bulks, in any places of the World, be they never so remote; as Fire in the hollow of the Moons Orb, Water in the bottom of the Sea, Air above the Clouds, and Earth below the Mines. But, these notions are onely to serve for certain Idea's of Elements; by which the forenamed bodies and the compounds of them, may be tryed and receive their doom of more or lesse pure and approaching to the nature from whence they have their deno∣mination. And yet I will not deny, but that such perfect Ele∣ments may be foumd, in some very little quantities, in mixed bodies; and the greatest abundance of them, in these four known bodies that we call, in ordinary practise, by the names of the pure ones: for they are least compounded, and approach most to the simpleness of the Elements. But to determine absolutely their existence, or not existence, either in bulk or in little parts, depends of the manner of action among bodies; which as yet we have not medled with.

CHAP. V. Of the operations of the Elements in general. And of their activities compared with one another.

HAving by our former discourse inquired out, what degrees and proportions of rarity and density compounded with * 1.36 gravity are necessary, for the production of the Elements: and first qualities, whose combinations frame the Elements: our next consideration, in that orderly progress we have proposed to our selves in this Treatise, (wherein our aim is to follow suc∣cessively the steps, which nature has printed out to us), will be to examine the operations of the Elements, by which they work upon one another. To which end, let us propose to our selves a rare and a dense body encountring one, another, by the impulse of some exterior agent. In this case, 'tis evident that, since rarity implyes a greater proportion of quantity, and quantity is nothing but divisibility; rare bodies must needs be more divisible then dense ones: and consequently, when two such bodies are press'd one against another, the rare body not being able to resist division so strongly as the dense one is, and being not permitted to retire back, by reason of the ex∣tern violence impelling it against the dense body; it follows, that the parts of the rare body must be sever'd, to let the dense one come between them; and so the rare body becomes di∣vided, and the dense body the divider. And, by this we see that the notions of divider and divisible, immediately follow rare and dense bodies; and so much the more properly agree to them, as they exceed in the qualities of Rarity and Density.

Likewise, we are to observe in our case, that the dense or dividing body must necessarily cut and enter further and fur∣ther into the rare or divided body; and so, the sides of it be joyn'd successively to new and new pars of the rare body that gives way to it, and forsake others it parts from. Now, the rare body being in a determinate situation of the Universe, (which we call being in a place, and is a necessary condition belong∣ing to all particular bodies); and the dense body comming to be within the rare body, whereas formerly it was not so: it fol∣lows, that it loses the place it had, and gains another. This ef∣fect, is that which we call local motion.

And thus we see, by explicating the manner of this action, * 1.37 that locall motion is nothing else but the change of that respect or relation, which the body moved has to the rest of the Universe, following out of Division: and the name of Locall Motion, formerly signifies only the mutation of a respect to other extrinsecall bodies, subsequent to that division. And this is so evident and agreeable to the notions that all mankind (who, as we have said, is judge and master of language) naturally frames of place, as, I wonder, much why any will labour to give other artificall and intricate doctrine of this that in it self is so plain and clear. What need is there to introduce an imaginary space (or, with Johannes Grammaticus, a subsistent quantity) that must run through all the World; and then entail to every body an aiery entity, an unconceiveable mood, an unintelligible Ubi, that, by an intrinsecall relation to such a part of the imaginary space, must thereto pin and fasten the bo∣dy it is in? It must needs be a ruinous Phylosophy that is grounded upon such a contradiction, as is the allotting of parts to that, which the Authors themselvs (upon the matter) ac∣knowledge to be merely nothing; and upon so weak a shift (to deliver them from the inconveniences that, in their course of doctrine, other circumstances bring them to) as is the volunta∣ry creating of new imaginary Entities in things, without any ground in nature for them. Learned men should express the advantage and subtilty of their wits, by penetrating further into nature then the vulgar; not by vexing and wresting it from its own course. They should refine and carry higher, not contradict and destroy, the notions of mankind, in those things it is the competent judge of; as it undoubtedly is of those primary notions which Aristotle has rank'd under Ten Heads: which (as we have touched before) every one can con∣ceive in gross; and the work of Scholars is to explicate them in particular, and not to make the Vulgar believe they are mistaken in framing those apprehensions that nature taught them.

Out of that which hath been hitherto resolvd 'tis manifest that Place really, (and abstracting from the operation of the un∣derstanding), is nothing else but the inward superficies of a body that compasses and immediately conteines another. Which

ordinarily, being of a rare body that doth not shew it self to us (namely, the Air), is for the most part unknown by us. But, because nothing can make impression on our minds and cause us to give it a name, otherwise then by being known: therfore our understanding, to make a compleat notion, must add some∣thing else to this fleeting and unremarkable Superficies, that may bring it to our acquaintance. And, for this end, we may consi∣der further; that, as this Superficies hath in it self, so the bodie enclosed in it gains a certain determinate respect to the stable and immoveable bodies that environ it. As for example, we understand such a Tree to be in such a place, by having such and such respects to such a Hill near it, or to such a House that stands by it, or to such a River that runs under it, or, to such an immoveable point of the Heaven that, from the Suns rising in the Equinox, is called East, and such like. To which purpose, it imports not whether these, that we call immoveable bodies and points, be truly so, or do but seem so to mankind. For, man talking of things according to the notions he frames of them in his mind (speech being nothing else but an expression to a∣nother man, of the images he hath within himself; and his noti∣ons being made according to the seeming of the things, he must needs make the same notions, whether the things be truly so in themselvs, or but seem to be so; when that seeming or appea∣rance is always constantly the same.

Now then, when one body, dividing another, gets a new immediate clothing; and consequently new respects to the sta∣ble * 1.38 and immoveable bodies (or seeming such) that environ it; we vary in our selves the notion we first had of that thing; concei∣ving it now accompanied with other circumstances and other respects then formerly it had. Which notion we express by saying, it has changed its place, and is now no longer where it was at the first. And this change of place we call Locall mo∣tion: to wit, the departing of a body from that hollow superficies which inclosed it, and its changing to another; wherby it gains new respects to those parts of the World that have, or in some sort may seem to have, immobility and fixed stableness: So as hence 'tis evident that the substance of▪ Locall motion con∣sists in Division; and that the alteration of Locality follows Division; in such sort as the becoming like or unlike of one

wall to another follows the action whereby one of them be∣comes white.

And therefore, in Nature, we are to seek for any entity or * 1.39 special cause of applying the moved body to a place, as place, (which is but a respect consequent to the effect of division); but only to consider, what real and physical action unites it to that other body, which is called its place, and truly serves for that effect. And consequently, they who think they have dis∣cover'd a notable subtilty, by bringing in an Entity to unite a Body to its Place, have strain'd beyond their strength, and grasped but a shadow. Which will appear yet more evident, if they but mark well, how nothing is divisible but what of it self (abstracting from division) is one. For the nature of Division is the making of many; which implies, that what is to be di∣vided must of necessity be not-many, before it be divided. Now Quantity being the subject of division, 'tis evident that, purely of it self and without any force or adjoyned helps, it must needs be one, wherever some outward agent doth not intro∣duce multiplicity upon it. And, whenever other things work upon quantity as quantity, it is not the nature and power of their operation to produce unity in it and make it one; for it is already one: but contrariwise, the immediate necessary effect that flows from them in this case is, to make one quantity many; according to the circumstances that accompany the divider and that which is to be divided. And therefore, although we may seek causes, why some one thing sticks faster together, then some other; yet to ask absolutely why a body sticks together were prejudicial to the nature of quantity: whose essence is to have parts sticking together; or rather to have such unity, as without which all divisibility must be excluded.

Out of which discourse it follows, that, in local motion, we are to look onely for a cause or power to divide, but not for any to unite. For, the very nature of quantity unites any two parts that are indistant from one another, without needing any other cement to glue them together: as we see the parts of water and all liquid substances presently unite themselves to other parts of like bodies, when they meet with them, and to solid bodies if they chance to be next them. And therefore 'tis vain to trouble our heads with Unions and imagina∣ry

Moods to unite a body to the place it is in; when their own nature makes them one as soon as they are immediate to each other. And accordingly, if, when we see a Boul move, we would examine the causes of that motion, we must consider the quantity of air or water it makes to break from the parts next to it, to give place to it self: and not speculate upon an in∣trinsecall relation from the body to a certain part of the imagi∣nary space, they will have to run through all things. And, by ballancing that quantity of air or water which it divides, we may arrive to make an estimate of what force the Boul needs to have for its motion.

Thus having declar'd that the locality of motion is but an extrinsecall denomination and no reality in the thing moved; * 1.40 we may now cast an eye upon a vast consequence that may be deduced out of what we have hitherto said. For, if we consider the nature of a Body, that is, that a Body is a Body by quantity; and that the formall notion of Quantity is nothing else but Di∣visibility; and that the adequate Act of Divisibility is Division, 'tis evident there can be no other Operation upon Quantity, nor (by consequence) among Bodies, but must either be such Divisi∣on as we have here explicated, or what must necessarily follow out of such division. And Division (as we have even now expli∣cated) being Locall Motion, 'tis evident, that All operations among Bodies are either, Local Motion, or such as follow out of Local motion. Which conclusion, however unexpected and at first hearing appearing a Paradox, will nevertheless by the ensuing work receive such evidence as it it cannot be doubted of; and that, not only by force of argumentation and by necessity of notions, (as is already reduced), but also by experience and declaratiosns of particulars, as they shall occur.

But now, to apply what we have said to our proposed sub∣ject: * 1.41 'tis obvious to every man, that, seeing the Divider is the agent in division and in Local motion; and dense bodies are by their nature dividers; the Earth must in that regard be the most active among the Elements, since it is the most dense of them all. But this seems to be against the Common judgment of all the searchers of nature, who unamimously agree that Fire is the most active Element: As also it seems to impugne what we

our selves have determin'd, when we said there were two active qualities, heat and cold; whereof the first was in its greatest excess in Fire, and the latter in water.

To reconcile these, we are to consider, that the action of Cold in its greatest height is composed of two parts; the one is a kind of pressing, and the other is penetration which requires appli∣cability. Of which two the former arises out of density, but the latter out of moderation of density, as I have declared in the precedent Chapter. Wherefore the former will exceed more in Earth, though the whole be more eminent in Water. For though, considering only the force of moving (which is a * 1.42 a more simple and abstracted notion, then the determination and particularization of the Elements, and is precedent to it) there∣in Earth hath a precedency over water: yet, taking the action, as it is determin'd to be the action of a particular Element, and as it concurs to the composition or dissolution of mixed bodies; in that consideration (which is the chief work of Elements, and requires an intime application of the Agents) Water hath the principality and excess over Earth.

As for Fire, it is more active then either of them: as will * 1.43 appear clearly, if we consider how, when Fire is applyed to fewel, and the violence of blowing is added to its own motion, it incorporates it self with the fewel, and in a small time converts a great part of it into its own nature, and shat∣ters the rest into smoak and ashes. All which proceeds from the exceeding smallness and dryness of the parts of fire; which being moved with violence against the fewel and thronging in multitudes upon it, easily pierce the porous substance of it, like so many extreme sharp Needles.

And, that the force of Fire is as great and greater then of Earth, we may gather out of our former discourse; where, ha∣ving resolved that density is the virtue by which a body is moved and cuts the medium, and again considering that celerity of motion is a kind of density (as we shall by and by declare) 'tis evident that, since blowing must of necessity press violently and with a rapid motion the parts of fire against the fewel, and so condense them exceedingly there, (both by their celerity, & by bringing very many parts together there,) it must

needs also give them activity and vertue to pierce the body they are beaten against.

New, that Celerity is a kind of Density, will appear, by com∣paring their natures. For if we consider that a dense body may be dilated so, as to possess and fill the place of a rare body that exceeded it in bigness, and, by that dilatation, may be divided into as many and as great parts as the rare body was divisible into; we may conceive that the substance of those parts was, by a secret power of nature, folded up in that little extension in which it was before. And even so, if we reflect upon two Rivers of equal channels and depths, whereof the one goes swif∣ter then the other; and determine a certain length of each channel, and a common measure of Time: we shall see that, in the same measure of time, there passes a greater bulk of wa∣ter in the designed part of the channel of the swifter stream, then in the designed part of the flower, though those parts be equal.

Nor imports it that in Velocity we take a part of time, whereas in Density it seems that an instant is sufficient; and, consequently, there would be no proportion between them: For, knowing Philosophers all agree that there are no In∣stants in time; and that the apprehension of them proceeds meerly from the manner of our understanding: And, as for parts in time, there cannot be assumed any so little, in which the com∣parison is not true; and so, in this regard, it is absolutely good.

And, if the Reader have difficulty at the disparity of the things which are pressed together, in Density and in Celerity; for that in Density, there is only Substance, & in Celerity there is also Quantity crowded up with the substence; he will soon receive satisfaction, when he shall consider that this disparity is to the advantage of what we say, and makes the nature of den∣sity more perfect in celerity; and consequently more power∣ful in fire then in earth. Besides, if there were no disparity, it * 1.44 would be a distinct species of density, but the very same.

By what we have spoken above, it appears how fire gets into fewel; now let us consider how it comes out: for the acti∣vity of that fierce body will not let it lie still and rest, as long as it has so many enemies round about it to rouse it up. We see then that, as soon as it has incoporated it self with the

fewel and is grown master of it, by introducing into it so ma∣ny of its own parts, like so many Souldiers into an Enemies Town); they break out again on every side with as much vio∣lence as they came in. For, by reason of the former resistance of the fewel, their continual streaming of new parts upon it, and one overtaking another there where their journey was stop'd (all which is increas'd by the blowing) doth so ex∣ceedingly condense them into a narrower room then their na∣ture effects, that, as soon as they get liberty and grow masters of the fewel (which at the first was their prison), they en∣large their place, and consequently come out and flie abroad; ever aiming right forwards from the point where they begin their journey: for, the violence wherewith they seek to ex∣tend themselves into a larger room, when they have liberty to do so, will admit no motion but the shortest, which is by a straight line.

So that if, in our phantasie, we frame an image of a round body all of fire; we must withall presently conceive, that the flame proceeding from it would diffuse it self every way indifferently in straight lines, so that, the source serving for the Center, there would be round about it an huge Sphere and of fire and light; unless some accidental and extern cause should determine its motion more to one part then to another. Which compass, because it is round and has the figure of a Sphere, is by Philosophers term'd the Sphere of its acti∣vity.

So that it is evident, the most simple and primary moti∣tion of fire is a flux in a direct line from the center of it to its circumference, taking the fewel for its center: as also that, when 'tis beaten against a harder body, it may be able to destroy it; though that body be in its own nature more dense then fire. For the body against which it presses either has pores, or has none (as, the Elements have none:) if it has pores, then the fire, by reason of the violent motion of the impel∣lent, drives out the little bodies which fill up those pores, &, suc∣ceeding in their room, and being multiply'd there, causes those effects which in our discourse of the Elements we assign'd to heat. But, if it hath no pores, it will be either rare or dense: if it be rare, then, if the force of the impellant be

greater than the resistance of the rare body, it will force the fire to divide the rare body. But if it be dense (as, some atome of earth), then, though at the first it cannot divide it, yet, by length of time and continual beating upon it, it may come to wear off some part of it; the force of the impellent by little and little bending the atome of the earth, by driving a conti∣nual stream of a lesser part of fire against some determinate part of the atome. By which word, Atome, no body will imagine we intend to express a perfect indivisible; but only the least sort of natural bodies.

CHAP. VI. Of Light: what it is.

HAving said thus much of fire; the near relation be∣tween it and Light invites us, in the next place, to bend * 1.45 our eyes, to that which uses to dazel theirs who look unweari∣ly upon it. Certainly, as, among all the sensible qualities, it is the principal; so, among all corporeal things, it seems to aim rightest at spiritual nature, and to come nearest it. And by some it has been judg'd to be spiritual; if our eyes be capable to see Spirits. No meaner man then Aristotle leads the the dance to hold light a quality; and mainly to deny it any bodily subsistence: And there has follow'd him no fewer, then almost all the world ever since. And the question imports no less, then the whole Doctrine of Qualities; for admit light to be a body, and hardly any man will hold up his hand in defence of any other quality; but if it be a quality then all others come in by parity and for company.

But before we go any further, it will not be amiss to ex∣press what we mean, when we reject qualities; and how, in some sense, we are content to admit them. According to that descripion that Phylosophers ordinarily make of them, (and especially the Modern) we can by no means give way to them. I confess ingeniously, I understand not what they mean by them; and I am confident, that neither do they. For, the very notion, that their first words seem to express of them, they contradict again, before they make an end of describing what they are. They will have them to be real

Entities or Things, distinct from the bodies they accompa∣ny: and yet; they deny them a subsistence or self-being, saying, they do but inhere in their subject which supports them; or, which is all one, that their being is a dependence on a subject.

If they will reflect upon what they say, and make their thoughts and their words agree, they'l find that the first part of their description makes them compleat substances; which, afterwards, in words they flatly deny: and 'tis impossi∣ble to reconcile these two meanings. A reall Entity or Thing must necessarily have an Existence or Being of its own; which they allow them: and, whatever hath so becomes a sub∣stance; for it subsists by its own Existence, or (to say plain∣er,) is what it is by its own Being, and needs not the exi∣stence of another thing to give it a Being. And then presently to to say that it doth not subsist of it self, or that it requires the subsistence of a substance to make it Be, is a pure contradiction to the former.

This arises from a wrong notion they make to themselvs of substance, existence, and subsistance: and from their not con∣sulting sufficiently with their own thoughts, as well as study∣ing in Books. They meet there with different terms; by help of which they keep themselves from contradiction in words, but not in effect. If the terms were rightly conceived and notions duely fitted to them, (which requires deep meditation on the things themselvs, and a brain free from all inaclination to siding, or affection to opinoins for the Authors sakes, before they be well understood and examin'd) many of those disputs would fall to the ground; in which oftentimes both sides lose themselvs and the question, before they come to an end. They are in the dark before they are aware: and then they make a noyse, only with terms; which, like too heavie weapons that they cannot weild, carry their strokes beyond their aim. Of such nature are the Qualities and Moods, that some modern Philosophers have so subtilised on. And, in that sense, we ut∣terly denie them: which being a question appertaining to Me∣taphysicks, it belongs not to our present purpose to ingage our selvs further in it.

But, as they are ordinarily understood in common conver∣sation,

we allow them. And our work is but to explicate and shew the particulars in retail, of what men naturally * 1.46 spake in grosse. For that serves their turn, to know what one another means: whereas, it belongs only to a Phylo∣sopher, to examine the causes of things. Others are con∣tent with the effects: and they speak truly and properly, when they design them. As for example: when they say that fire burns by a quality of heat that it has, or that a Deye is square by the qualitie of a cubicall figure that is in it; they speak as they should do. But, if others will take occasion upon this, to let their understanding give a Being to these qualities, distinct from the substances in which they conceive them; there they miss. If we consider the same man hungry, or thirsty, or weary, or sleepy, or standing, or sitting; the understanding presently makes within it self reall things of sleep, hunger, thirst, weariness, standing, and sitting: Whereas indeed, they are but different affections or situations of the same body. And therefore we must beware of applying these notions of our mind, to the things as they are in themselves: as much as we must, of conceiving those parts to be actually in Continued Quantity, wherof we can frame actually distinct notions in our understanding. But as, when ordinary men say, that a Yard contains three feet; 'tis true, in this sence, that three feet may be made of it, but, whiles 'tis a yard, 'tis but one quantitie or thing, and not three things: so they, who make profession to examine rigourous∣ly the meaning of words, must explicate in what sense it is true that Heat and Figure (our former examples) are quali∣ties; for such we grant them to be, and in no wise contradict the common manner of speech, which enters not into the Phy∣losophicall nature of them.

We say then, that Qualities are nothing else but the Proprie∣ties, or Particularities, wherin one thing differs from another. And therfore Logicians call substantiall Differences, substan∣tiall Qualities; and say, they are predicated in Quale quid. But, the Predicament of Quality is orderd, by Aristole, to con∣clude in it those differences of things, which are neither Sub∣stantiall nor quantitative, and yet are intrinsecall and absolute. And so, that which the understanding calls heat, and makes a

notion of (distinct from the notion of the fire from whence it issues to burn the wood that is near it) is nothing else, in the fire, but the very sustance of it in such a degree of rarity; or a continual stream of parts, issuing out of the main stock of the same fire, that enters into the wood, and by its rarity makes its way through every little part, and divides them. All which actions are comprised by the understanding, under one notion of burning; and the power, (which is fire it self) to do these actions, under one notion of the qualitie of heat: though burning in effect, and explicated Philosophically, be nothing else but the continuance of those material motions we have even now described. In like manner, the cubical figure of a deye is nothing else but the very bodie of the deye it self, limited by other bodies from being extended beyond those di∣mentions it hath: and so, the qualitie of figure or squareness, which in common speech is said to be in it, is truly sub∣stance it self, under such a consideration as is expressed by that word.

But, to come to our question, on the decision of which de∣pends * 1.47 the fate of all the fictitious Entities which the Schools are term'd Qualities. The chief motives that perswade Light to be one of those may, to my best remembrance, be reduced to five several heads. The first is, that it illuminates the Air in an instant, and therefore cannot be a body: for a body re∣quires succession of time to move in; wherereas, this seems to spread it self over the whole Hemisphere in an instant. For, as far as the Sun is distant from us, he no sooner raises his head above our Horizon, but his darts are in our face: and gene∣rally, no imagination can be framed of any motion it has in its dilatation.

The next is, that, whereas no body can admit another into its place without being removed away it self, to leave that room to the advenient one; plain experience shews us daily, that two lights may be in the same place; and the first is so far from going away at the coming of the second, that the bringing in of a second Candle, and setting it near the first, increases the light in the room; which diminishes again, when the second is removed away. And, by the same rea∣son, if light were a body, it should drive away the aire

(which is likewise a body) wherever it is admitted: for, within the whole sphere of the irradiation of it, there is no point, wherein one may set their eye, but light is found. And therefore, if it were a body, there would be no room for air, in that place which light takes up. And likewise, we see that it penetrates all solid bodies (and particularly glass); as expe∣rience shews, in wood, stone, metals, and any other body what∣ever, if it be made thin enough.

The third argument why light cannot be a body is, that if it were so, it can be none other but fire; which is the subtilest and most rarified of all bodies whatever. But, if it be fire, then it cannot be without heat; and consequently, a man could not feel cold in a sun-shining day: The contrary of which is ap∣parent all winter long, whose brightest dayes oftentimes prove the coldest; And Galileus, with divers others since, did use from the Sun to gather light, in a kind of stone that is found in Italy, (which is therefore by them call'd la calamita della luce), and yet no heat appeared in it. A Glow-worm will give light to read by, but not to warm you any whit at all: And it is said, that Diamonds and carbuncles will shine like fire in the greatest darks; yet no man ever complain'd of being serv'd by them as the foolish Satyre was, by kissing a burning coal. On the contrary side; if one consider, how great heats may be made without any light at all; how can one be perswaded that light & heat should be the same thing, or indeed any whit of kin?

The fourth motive, to induce us to believe that light cannot be a body, is the sudden extinction of it; when any solid body comes between the fountain of it, and the place where it sends its beams. What becomes of that great expansion of light that shined all about, when a cloud enterposes it self between the body of the Sun and the streams that come from it? Or when it leaves our Horizon to enlighten the other world? His head is no sooner out of our sight, but at the instant all his beams are vanished. If that which fills so vast a room were a body, some∣thing would become of it; it would at the least be chang'd to some other substance, and some reliques would be left of it, as when ashes remain of burned bodies; for, nature admits not the annihilation of any thing.

And, in the last place, we may conceive that if light were a bo∣dy,

it would be shaken by the winds and by the motion of the air; and we should see it quaver in all blustring weather. Therefore summing up all we have said, it seems most im∣probable, and indeed wholly impossible, that light should be a Body; and consequently it must have his place among Qualities.

But, on the otherside; before we apply our selves to answer * 1.48 these objections, let us make a short survey of those induce∣ments, that prevail with us to believe light a body, notwith∣standing so forcible oppositions. I admit so far of the third argument, as to allow light to be fire; for indeed it cannot be imagin'd any thing else, all properties agreeing so fully be∣tween them: But withal I must adde, that it is not fire in every form, or fire joyn'd with every substance, that expresses it self by light; but it is fire extremely dilated and without mix∣ture of any other grosse body. Let me hold a piece of linen or paper close by the flame of a candle, and, by little and little, remove it further and further off; and methinks my very eyes tell me, that there is upon the paper some part of that which I see in the candle, and that it grows still less and less, as I re∣move the paper further from it: so that if I would trust my sense, I should believe it as very a body upon the paper, as in the candle; though infeebled, by the laxity of the channel in which it flows.

And this seems to be strengthen'd by the consideration of the adversaries position: for if it were a quality, then, seeing it hath no contrary to destroy or stop it, it should still produce an equal to it self, without end or growing feeble; whenever it meets with a subject capable to entertain it, as air is.

The better to apprehend how much this faint resemblance * 1.49 of flame upon the paper maketh for our purpose, let us turn the leaf; and imagine in our thoughts, after what fashion that fire which is in the flame of a little candle would appear to us, if it were dilated and stretch'd out to the utmost extent that excess of rarity can bring it to. Suppose that so much flame, as would fill a cone of two inches height and half an inch Diameter, should suffer so great an expansion, as to reple∣nish with his light body a large chamber: and then, what can we imagine it would seem to be? How would the con∣tinual

driving it into a thinner substance, as it streams in a perpetual flood from the flame, seem to play upon the paper? And then judg whether it be likely to be a body or no; when our discourse suggests to us, that, if it be a body, those very appearances must follow, which our eyes give us evidence are so in effect. If gold, beaten into so airy a thinness, as we see gilders use, remains still Gold, notwithstanding the wonder∣full expansion of it: why shall we not allow, that fire, dilated to its utmost period, shall still remain fire; though extreamly rarified beyond what it was?

We know that fire is the rarest and the subtilest substance that nature hath made among bodies; and we know likewise, * 1.50 that it is ingendred by the destroying and feeding upon some other more grosse body: let us then calculate, when the oyl, or tallow, or wax of a candle, or the bulk of a faggot or billet, is dilated and rarified to the degree of fire; how vast a place must it take up?

To this let us add what Aristotle teaches us; that fire is not like a standing pool, which continues full with the same water; and as it has no waste, so has it no supply: but it is a fluent and brook-like current. Which also we may learn, out of the perpetual nutriment it requires: for, a new part of few∣el being converted into a new part of fire (as we may ob∣serve in the little atomes of Oyl or melted wax, that continu∣ally ascend apace up the wieke of a burning candle or lamp; of necessity the former must be gone to make room for the latter; and so a new part of the river is continually flowing.

Now then, this perpetual flux of fire, being made of a grosse body that, so rarified, will take up such a vast room, if it die not at the instant of its birth, but have some time to subsist (be it never so short,) it must needs run some distance from the fountain whence it springs. Which, if it do, you need not wonder, that there should be so great an extent of fire as is requisite to fill all that space which light replenishes; nor that it should be still supplyed with new, as fast as the cold of the aire kills it. For, considering that flame is a much grosser substance then grosse fire, by reason of the mixture with it of that viscous oyly matter, which, being drawn out of the wood and candle, serves for fewel to the fire and

is, by little and little, converted into it; and withal reflecting on the nature and motion of fire, which is, to dilate it self ex∣treamly, and to fly all about from the center to the circumfe∣rence, you cannot choose but conceive that the pure fire, strug∣ling to break away from the oyly fewel, which is still turning into new fire, doth at length free his wings from that birdlime; and then flies abroad with extream swiftness, & swels and dilates it self to a huge bulk, now that it has gotten liberty: and so fills a vast room; but remains still fire till it die. Which it no sooner doth, but it is still supply'd with new streams of it, that are continually strain'd, & as it were, squees'd out of the thick flame, which imprison'd, and kept it within it; till growing fuller of fire then it could contain (by reason of the continual attenuating the oyly parts of it, and converting them into fire), it gives liberty to those parts of fire, that are next the superficies, to fly whither their nature will carry them.

And, thus, discourse would inform a Blind man (after he has well reflected on the nature of fire), how it must needs fill a mighty extent of place; though it have but a narrow begin∣ning at its spring head: and that there, by reason of the condensation of it and mixture with a grosser body, it must needs burn other bodies; but that, when it is freed from such mixture and suffers an extream expansion, it cannot have force to burn, but may have means to express it self to be there pre∣sent, by some operation of it upon some body that is refin'd and subtilized enough to perceive it. And this operation a seeing man will tell you is done upon his eyes: whose fitness to re∣ceive impression from so subtile an Agent, Anatomists will teach you. And I remember, how a blind Schoolmaster, that I kept in my house to teach my children, (who had extream subtile spirits, and a great tenderness through his whole body; and met with few distractions to hinder him from observing any im∣pression, never so nicely made upon him) used often to tell me, that he felt it very perceptibly in several parts of his body; * 1.51 but especially in his brain.

But, to settle us more firmly in the perswasion of light's be∣ing a body, and consequently, fire, let us consider, that the pro∣perties of a body are perpetually incident to light: look what rules a ball will keep in its rebounds, the same doth light in

its reflections; and the same demonstration alike convinces the one and the other. Besides, light is broken like a body; as, when 'tis snapped in pieces by a tougher body: it is gather'd together in a little room by looking or burning glasses; as wa∣ter is, by ordering the gutters of a house so as to bring into one cistern all that rains dispersedly upon the whole roof. It is sever'd and dispers'd, by other glasses; and is to be wrought upon, and cast hither and thither at pleasure: all, by the rule of other bodies. And what is done in light, the same will likewise be done in heat, in cold, in wind, and in sound. And the very same instruments that are made for light, will work their effects in all these others, if they be duly managed.

So that certainly, were it not for the authority of Aristotle and his learned followers, that presses us on the one side; and for the seemingness of those reasons we have already mention'd, which perswades us on the other side: our very eyes would car∣ry us by stream into this consent, that light is no other thing but the nature and substance of fire, spread far and wide, and freed from the mixture of all other gross bodies. Which will appear yet more evident, in the solutions of the oppositions we have brought against our own opinion: for, in them there will oc∣cur other arguments of no less importance to prove this ve∣rity, than these we have already proposed.

CHAP. VII. Two objections answer'd against light being fire; with a more ample proof of its being such.

HAving then said thus much to perswade us of the corpo∣reity * 1.52 of this subtile thing, that so queintly plays with our eyes; we will in the next place examine those objections that, at the beginning, we set down against its being a body: and if, after a through discussion of them, we find they do in truth conclude nothing of what at the first sight they bear so great a shew of, but that we shall be able perfectly to solve and enerve their force; no body will think it rashness in us to crave leave of Aristotle, that we may dissent from him in a matter that he has not look'd to the bottom of; and whose opinion therin

cannot be defended from plain contradictions and impossibili∣ties. 'Tis true, never any one man looked fo far as he into the bowels of nature; he may be rightly termed the Genius of it, and whoever follows his principles in the main cannot be led into errour: but we must not believe that he or any man else, who relies upon the strength and negotiation of his own rea∣son, ever had a priviledge of infallibility entail'd to all he said. Let us then admire him for what he has deliver'd us: and where he falls short or is weary in his search, and suffers himself to be born down by popular opinions against his own principles (which happens very seldom to him), let us seek to supply and relieve him.

But, to pursue our intent: We will begin with answerin, the third objection; which is, that if light were fire it must heat as well as enlighten, where it shines. There's no doubt but it doth so▪ as is evident by the weather∣glasses, and other artificiall musical instruments (as Organs and Virginals that played by themselvs) w••ch Cornelius Drebbel (That admirable master of Mechanicks) made to shew the King. All which depends upon the rarefaction and condensation of some subtile body, conserv'd in a cavity with∣in the bulk of the whole instrument: for, assoon as the Sun shined, they would have motion and play their parts. And, questionless, that grew out of the rarefaction of the sub∣tile liquor he made use of; which was dilated assoon as the air was warmd by the Sun-beams: Of whose operation it was so sensible, that they no sooner left the Horizon, but its motion ceased; And if but a cloud came between the in∣strument and them, the musick would presently go slower time. And the ancient miracle of Memnons statue seems to be a juggling of the Ethiopian priests, made by the like in∣vention.

But, though he and they found some spirituall and refined natter, that would receive such notable impressions from * 1.53 so small alterations of temper; yet it is no wonder that our gross bodies are not sensible of them: for we cannot feel heat, unless it be greater then that which is in our sense, And the heat there must be in proportion to the heat of our bloud; which is an high degree of warmth: and therfore 'tis very pos∣sible,

that an exceeding rarified fire, may cause a far lesse im∣pression, of heat then we are able to feel. Consider how, if you set pure spirit of wine on fire, and so convert it into actual flame; yet it will not burn, nor scarce warm your hand: and then can you expect that the light of a candle, which fills a great room, should burn or warm you as far as it shines?

If you would exactly know, what degree of heat and power of burning that light has, which (for example) shines upon the wall in a great chamber, in the midst wherof there stands a can∣dle: do but calculate what overproportion of quantitie all the light in the whole room bears, to the quantity of the little flame at the top of the candle; and that is the overproportion of the force of burning which is in the candle, to the force of burning which is in so much light at the wall as, in ex∣tension, is equall to the flame of the candle. Which when you have considered, you will not quarrel at its not warming you at that distance: although you grant it to be fire, stream∣ing out from ••e flame as from the spring that feeds it, and ex∣treamly dilated (according to the nature of fire, when it is at liberty), by going so far without any other grosse body to im∣prison or clog it.

'Tis manifest, that this rule of examining the proportion of burning in so much of the light as the flame is (by cal∣culating the proportion of the quantity or extension of all the light in the room to the extension of the flame of the candle, and then comparing the flame of the candle to a part of light equall in extension unto it) is a good and infallible one, if we abstract from accidental inequalities: since both the light and the flame are in a perpetual flux; and all the light was first in the flame, which is the spring from whence it conti∣nually flows. As in a river, where every part runs with a settled stream; though one place be straighter, and another broader: yet of necessity, since all the water that is in the broad place came out of the narrow, it must follow that, in equal portions of time, there is no more water where it has the liberty of a larg channel, then where the banks press it into a narrow bed; so that there be no inequalities in the bottome.

In like manner, if, in a large stove, a basin of water be con∣verted

into steam; that rarified water, which then fills the whole Stove, is no more then what the Basin contain'd before: and consequently, the power of moistening, which is in a foots extension (for example) of the stove wherein that steam is, must be, in proportion to the vertue of wetting in the foot ex∣tension of water, as the quantity of that great room, which the steam fills, is to the quantity of the water contain'd in the basin. For, although the rarified water be not in every least part of that great place it seems to take up, by reason that there is Air in which it must swim; yet the power of wetting that was in the Basin of water is dilated through the whole room, by the conjunction of the Myst or Dew to all the sensible parts of the Air that is in the room: and consequently the pow∣er of wetting, which is in any foot of that room, is, in a manner, as much less then the power of wetting which was in the foot of water, as if the water were rarified to the quantity of the whole room, and no air were left with it.

And, in the same manner it fares with dilated fire, as it doth with dilated water: with only this difference, peradven∣ture, that Fire grows purer and more towards its own na∣ture, by dilatation: whereas water becomes more mix'd, and is carried from its nature, by suffering the like effect. Yet, dilated water will, in proportion, moisten more then di∣lated fire will burn, for the rarefaction of water brings it nearer to the nature of air (whose chief propriety is moi∣sture,) and the fire that accompanies it, when it raiseth it in∣to steam, gives it more powerful ingression into what body it meets withal: whereas fire, when 'tis very pure, and at entire liberty to stretch and spread it self as wide as the na∣ture of it will carry it, gets no advantage of burning by its mixture with air; and although it gains force by its purity, yet, by reason of its extreme rarefaction, it must needs be extreamly faint. But if, by the help of Glasses, you will gather into less room what is diffused into a great one, and so con∣dense it as much as it is (for example) in the flame of a candle: then that fire or compacted light will burn much more forcibly then so much flame: for there is as much of it in quan∣tity (excepting what is lost in the carriage of it, and it is held in together in as little room, and it has this advantage

besides, that 'tis clog'd with no grosse body to hinder the acti∣vity of it.

It seems to me now, that the very answering this objection doth (besides repelling the force of it) evidently prove, that * 1.54 light is nothing but fire, in its own nature, and exceedingly di∣lated: for, if you suppose fire (for example, the flame of a candle) to be stretch'd out to the utmost expansion that you may well imagine such a gross body is capable of; 'tis impossible it should appear and work otherwise then it doth in light, as I have shewd above. And again, we see plainly that light gather'd to∣gether burns more forcibly then any other fire whatever, and therefore must needs be fire.

Why then shall we not confidently conclude, that what is fire before it gets abroad, and is fire again when it comes together, doth likewise remain fire during all its journey? Nay, even in the journey it self we have particular testimony that it is fire: for light, returning back from the earth charg'd with little atomes (as it doth in soultry gloomy weather), heats much more than before; just as fire doth when it is imprisoned in a dense body.

Philosophers ought not to judge by the same rules that the common people doth. Their gross sense is all their guide; and * 1.55 therfore they cannot apprehend any thing to be fire that doth not make it self to be known for such by burning them: But, he that judiciously examines the matter, and traces the pedigree and period of it, and sees the reason why▪ in some circumstan∣ces, it burns, and in others, not; is too blame, if he suffer himself to be led by others ignorance, contrary to his own reason. When they, that are curious in perfumes, will have their chamber fil'd with a good scent, in a hot season that agrees not with burning perfumes; and therfore make some odoriferous water be blown about it, by their servants mouthes that are dexterous in that ministery, (as is used in Spain in the Summer time): every one that sees it done (though on a sudden the wa∣ter be lost to his eyes and touch, and is only discernable by his nose, yet) is well satisfied that the scent which recreates him is the very water he saw in the glass, extremely dilated by the forcible sprouting of it out from the servants mouth; and will, by little and little, fall down and become again pal∣pable

water as it was before; and therefore doubts not but it is still water, whiles it hangs in the air divided into little atomes. Whereas, one that saw not the beginning of this ope∣ration by water, nor observ'd how in the end it shews it self again in water, might the better be excused, if he should not think that what he smel'd were water blown about the air; nor any substance of it self (because he neither sees nor handles it), but some adventitious quality, he knows not how, adhering to the air. The like difference is between Philosophers that proceed orderly in their discourses, and others that pay them∣selves with terms which they understand not: The one see evidence in what they conclude; whiles the others guesse wildly at random.

I hope the Reader will not deem it time lost from our main drift, which we take up thus in examples and digressions: for, if * 1.56 I be not much deceived, they serve exceedingly to illustrate the matter. Which I hope I have now rendred so plain, as no man, that shall have well weighed it, will expect that Fire, dilated into that rarified substance which mankind (who, ac∣cording to the different appearance of things to their sense, gives different names to them) calls Light, should burn like that grosser substance which, from doing so, they call fire; nor doubt, but that they may be the same thing more or less atte∣nuated; as leaf-gold that flies in the air, as light as down, is as truly gold as that in an ingot, which, being heavier then any other substance, falls most forcibly to the ground.

What we have said of the unburning fire (which we call light) streaming from the flame of a Candle, may easily be apply'd to all other lights deprived of sensible heat; whereof some appear with flame, others without it. Of the first sort are the innoxious flames that are often seen on the hair of mens heads and horses manes, on the Masts of ships, over graves, and fat marish grounds, and the like: and of the latter sort are Glow-worms, and the light-conserving stones, rotten wood, some kinds of fish and of flesh when they begin to putrifie; and some other things of the like nature.

Now, to answer the second part of this objection, That we * 1.57 daily see great heats without any light, as well as much light

without any heat; and therefore light and fire cannot be the * 1.58 same thing: You may call to mind, how Dense bodies are ca∣pable of great quantities of Rare ones; and thereby it comes to pass that bodies, which repugn to the dilatation of flame, may nevertheless have much fire inclosed in them. As, in a stove, let the fire be never so great, yet it appears not outwards to the sight; although that stove warm all the rooms near it: So, when many little parts of heat are imprison'd in as many little cells of gross earthly substance, (which are like so many little stoves to them), that imprisonment will not hinder them from being very hot to the sense of feeling; which is most per∣ceptible of dense things. But, because they are choak'd with the closeness of the gross matter wherein they are closed, they cannot break out into a body of flame or light, so to discover their nature: which (as we have said before) is the most un∣fit way for burning; for we see that light must be condensed to produce flame and fire, as flame must be, to burn violently.

Having thus clear'd the third objection, (as I conceive,) let us go on to the fourth; which requires that we satisfie their in∣quisition, * 1.59 who ask, what becomes of that vast body of shining light (if it be a body) that fills all the distance between hea∣ven and earth; and vanishes in a moment, assoon as a cloud or the Moon interposes it self between the Sun and us, or that the Sun quits our Hemisphere? No sign at all remains of it after its extinction as doth of all other substances, whose destruction is the birth of some new thing. Whither then is it flown? we may be perswaded that a mist is a corporeal substance, because it turns to drops of water upon the twigs that it invirons: and so we might believe light to be fire, if, after the burning of it out, we found any ashes remaing; but experience assures us, that, after it is extinguish∣ed, it leaves not the least vestigium behind it of having been there.

Now, before we answer this objection, we will intreat our Adversary to call to mind, how we have, in our solution of the former, declared and proved that the light, which (for example) shines from a candle, is no more then the flame is, from whence it springs, the one being condensed and the other di∣lated; and that the flame is in a perpetual flux of consumption

about the circumference, and of restauration at the center where it sucks in the fewell; and then we will enquire of him, what becomes of the bodie of flame which so continual∣ly dies and is renewed, and leaves no remainder behind it; as well as he doth of us, what becomes of our body of light, which in like manner is alwaies dying and alwaies springing fresh? And when he hath well considered it, he will find that one answer will serve for both.

Which is, That, as the fire streams out from the fountain of it, and growes more subtile by its dilatation, it sinks the more easily into those bodies it meets withall: the first of which, and that environs it round about, is aire. With air, then, it mingles and incorporates it self, and, by consequence, with the other little bodies that are mingled with the aire; and in them it re∣ceives the changes which nature works: by which it may be turn'd into the other Elements, if there be occasion; or be still conserv'd in bodies that require heat.

Upon this occasion, I remember a rare experiment, that a * 1.60 Noble-Man of much sincerity, and a singular friend of mine, told me he had seen: which was, That, by meanes of glasses made in a very particular manner, and artificially placed one by ano∣ther, he had seen the Sun-beams gather'd together, and precipi∣tated down into a brownish or purplish red powder. There could be no fallacy in this operation: for, nothing whatever was in the glasses when they were placed and disposed for this intent; and it must be in the hot time of the year, else the ef∣fect would not follow. And of this Magistry he could gather some dayes near two ounces in a day. And it was of a strange volative nature, and would pierce and imprint his spiritual qua∣lity into gold it self (the heaviest and most fixed body we con∣verse withall) in a very short time. If this be plainly so, with∣out any mistaking; then mens eyes and hands may tell them what becomes of light when it dies, if a great deal of it were swept together. But, from what cause soever this experience had its effect, our reason may be satisfied with what we have said above; for I confesse, for my part, I beleeve the appea∣ring body might be something that came along with the Sun∣beams, and was gather'd by them; but not ther pure substance.

Some peradventure will object those lamps, which both an∣cient

and modern writers have reported to have been found in Tombes and Urns; long time before closed up from mens repair * 1.61 to them, to supply them with new fewel: and therefore they believe such fires to feed upon nothing; and consequently, to be inconsumptible and perpetual. Which if they be, then our doctrine, that will have light to be nothing but the body of fire perpetually flowing from his center and perpetual dying, can∣not be sound: for, in time, such fires would necessarily spend themselves in light; although light be so subtile a substance, that an exceeding little quantity of fewel may be dilated into a vast quantity of light. However, there would be some consump∣tion; which, how imperceptible soever in a short time, yet, after a multitude of revolutions of years, must needs discover it self.

To this I answer: That, for the most part, the witnesses, who testifie originally the stories of these lights, are such as a ratio∣nal man cannot expect from them that exactness or nicitie of observation, which is requisite for our purpose. For, they are usually gross labouring people, who, as they dig the ground for other intentions, Stumble upon these Lamps by chance be∣fore they are aware: and commonly they break them in the finding, and imagine they see a glimpse of light; which va∣nishes before they can in a manner take notice of it, and is, peradventure, but the glistering of the broken glass, or glazed pot, which reflects the outward light, assoon as, by rummaging in the ground and discovering the Glass, the light strikes upon it, (in such manner as sometimes a Diamond, by a certain incountring of light in a dusky place, may, in the first twinkling of the motion, seem to sparkle like fire.) And afterwards, when they shew their broken Lamp, and tell their tale to some man of a pitch of wit above them, who is curious to inform himself of all the circumstances that may concern such lights; they strain their memory to answer him satisfacto∣rily unto all his demands: and thus, for his sake, they per∣swade themselves to remember what they never saw; and he again, on his side, is willing to help out the story a little. And so after a while, a very formal and particular relation is made of it. As happens in like sort in reporting of all strange and unusual things; when even those, that in their

nature abhor from lying, are naturally apt to strain a little and fashion up in a handsome mould, and almost to perswade them∣selves they saw more then they did: so innate it is to every man, to desire the having of some preeminence beyond his neigh∣bours; be it but in pretending to have seen something which they have not.

Therefore, before I engage my self in giving any particular answer to this objection of pretended inconsumptible lights, I would gladly see the effect certainly averred and undoubtedly proved: For, the testemonies which Fortunius Licetus produces (who has been very diligent in gathering them; and very sub∣〈◊〉〈◊〉 in discoursing upon them; and as the exactest Author that has written upon this subject) do not seem to me to make that certainty, which is required for the establishing of a ground in Philosophy. Nevertheless, if there be any certain experience in this particular, I should think there might be some Art, by circulation of fewel, to maintain the same light for a great company of years: But, I should not easily be perswaded, that either flame or light could be made, without any manner of consuming the body which serves them for fewel.

CHAP. VIII. An Answer to three other Objectious formerly proposed, against Light being a Substance.

HAving thus defended our selves from their Objections, * 1.62 who would not allow light to be fire; and having satisfied their inquisition, who would know what becomes of it when it dyes, if it be a body: we will now apply our selves to answer their difficulties, who will not let it pass for a body, because it is in the same place with another body; as, when the Sun-beams enlighten all the air, and when the several lights of two di∣stinct Candles are both of them every where in the same room. Which is the substance of the second main objection.

This, of the justling of the aire, is easily answered thus: that the aire, being a very divisible body, doth without resistance, yield as much place as is requisite for light. And that light,

though our eyes judge it diffused every where, yet is not truly in every point or atome of air: but, to make us see it every where, it suffices that it be in every part of the air which is as big as the black or sight of our eye; so that we cannot set our eye in any position, where it receives not impressions of light. In the same manner as Perfumes, which, though they be so gross bodies that they may be sensibly wasted by the wind, yet ••o fill the air, that we can put our nose in no part of the room, where a perfume is burned, but we shall smell it: And the like is of mists; as also of the sprouted water to make a perfume, which we mention'd above.

But, because pure discourses, in such small thrids as these, 〈◊〉〈◊〉 but weakly bind such Readers as are not accustom'd to them; and I would (if possible) render this Treatise intelligible to every rational man, how ever little vers'd in Scholastick learning (among whom I expect it will have a fairer passage, then among those that are already deeply imbued with other principles): let us try if we can herein inform our selves by our sense, and bring our eyes for witness of what we say. He then, that is desirous to satisfie himself in this particular, may put himself in a dark room, through which the Sun sends his beams by a cranie or little hole in the wall: and he will discover a multitude of little atomes flying about in that little stream of light; which his eye cannot discern, when he is en∣viron'd on all sides with a full light. Then, let him examine whether or no there be light in the midst of those little bodies; and his own reason will easily till him, that, if those bodies were as perspicuous as the air, they would not reflect upon our eyes the beams by which we see them: And therefore he will boldly conclude, that at the least such parts of them as reflect light to us do not admit it, nor let it sink into them. Then let him consider the multitude of them, and the little distance betwixt one another; and how nevertheless they hinder not our sight, but we have it free to discover all objects beyond them, in what position soever we place our eye. And, when he thus perceives that these opacous bodies, which are every where, do not hinder the eye from judging light to have an equal plenary diffusion through the whole place that it irra∣diates; he can have no difficulty to allow air, (that is dia∣phanous,

and more subtile far then they, and, consequently, divi∣sible into lesser atomes, and, having lesser pores, gives less scope to our eyes to miss light, then they do) to be every where mingled with light, though we see nothing but light, and cannot discern any breach of it.

Especially, when he shall adde to this consideration, that the subtile body, which thus fills the air, is the most visible thing in the world; and that whereby all other things are seen: and that the air it mingles it self with, is not at all visible, by reason of the extreme diaphaneity of it, and easie reception of the light in every pore of it, without any resi∣stance or reflection: and that such is the nature of light, as it easily drowns an obscure body, if it be not too big: and not onely such, but even other light bodies; for so we know as well the fixed Stars as the Planets are conceal'd from our sight, by the nearness to the Sun, neither the lightness of the one, nor the bigness of the other prevailing against the darkning of an ex∣uperant light; and we have daily experience of the same in very pure chrystal glasses, and in very clear water, which though we cannot discern by our sight if they be certain positions, nevertheless by experience we find that they reflect much light, and consequently have great store of opacous parts. And then he cannot choose but conclude, that it is impossible but light should appear as it doth, to be every where, and to be one continued thing; though his discourse withal assure him it is every where * 1.63 mingled with air.

And this very answer, I think, will draw with it, by conse∣quence, the solution of the other part of the same objection; which is, of many lights joyning in the same place; and the same is likewise concerning the images of colours every where cros∣sing one another without hindrance. But, to raise this contem∣plation a strain higher, let us consider, how light, being the most rare of all known bodies, is, of its own nature, (by reason of the divisibility that followeth rarity) divisible into lesser parts then any other; and particularly then flame, which, being mi∣xed with smoke and other corpulency, falls very short of light: And this, to the proportion in which it is more rare then the body 'tis compared to. Now, a great * 1.64 Mathematician, ha∣ving devised how to measure the rarefaction of Gun-pow∣der

into flame, found the Diameter fifty times increased; and so concluded, that the body of the flame was, in proportion to the body of the Gun-powder it was made of, as 125000. is to one. Wherfore, by the immediately proceeding consequence, we find that 125000 parts of flame may be couched in the room of one least part of gunpowder; and peradventure ma∣ny more, considering how porous a body Gun-powder is. Which being admitted, 'tis evident that, although light were as gross as the flame of Gun-powder, and Gun-powder were as solid as gold; yet there might pass 125000. rayes of light, in the space wherin one least part of Gun-powder might be contained: which space would be absolutely invisible to us, and be contained many times in the bigness of the sight of a mans eye. Out of which we may gather, what an infinity of objects may seem to us to cross themselvs in the same indi∣visible place; and yet may have room sufficient for every one to pass his way, without hindring his fellow. Wherfore, see∣ing that one single light could not send rayes enough to fil eve∣ry little space of aire that is capable of light, (and the less, the further it is from the flame); 'tis obvious enough to conceive how, in the space where the air is, there is capacity for the rays of many candles.

Which, being well sum'd up, will take away the great ad∣miration how the beams of light, though they be corporeall, can in such great multitudes, without hindering one another, enter into bodies and come to our eye: and will shew, that 'tis the narrowness of our capacities, and not the defect of nature, which makes these difficulties seem so great. For, she hath suffi∣ciently provided for all these subtile operations of fire; as also for the entrance of it into glass, and into all other solid bo∣dies that are Diaphanous (upon which was grounded the last instance the second objection pressed): for, all such bodies be∣ing constituted by the operation of fire, (which is alwaies in motion); there must needs be ways left for it both to enter in, and to evaporate out. And, this is most evident in glass: which, being wrought by an extreme violent fire and swelling with it, (as water and other things do, by the mixture of fire) must neces∣sarily have great store fire in it self whiles it is boyling; as we see by its being red hot. And, hence it is that the workmen

are forced to let it cool by degrees in such relentings of fire, as they call their nealing heats; lest it should shiver in pieces, by a violent succeeding of air in the room of the fire; for, that, being of greater parts then the fire, would strain the pore of the glass too suddenly, and break it all in pieces to get ingressions; whereas, in those nealing heats the air being rarer, lesser parts of it succeed to the fire, and leisurely stretch the pores without hurt. And, therefore, we need not wonder, that light passes so easily through glass; and, much less, that it gets through o∣ther bodies; seeing the experience of Alchymists as∣sures us. 'tis hard to find any other body so impenitrable as glass.

But now, to come to the answer of the first, and, in appear∣ance, * 1.65 most powerful objection, against the corporeity of light; which urges, that its motion is perform'd in an instant, and therefore cannot belong to what is material and cloth'd with quantity. We will endeavour to shew how unable the sense is to judge of sundry sorts of motions of Bodies, and how grosly it is mistaken in them: And then, when it shall appear that the motion of light must necessarily be harder to be obser∣ved, then those others; I conceive, all that is rais'd against our opinion, by so incompetent a judge, will fall flat to the ground.

First then, let me put the Reader in mind, how, if ever he mark'd children when they play with firesticks, they move and whirle them round so fast, that the motion will cosen their eyes, and represent an entire circle of Fire to them: and were it somewhat distant, in a dark night, that one play'd so with a lighted Torck, it would ap∣pear a constant Wheele of fire, without any discerning of motion in it. And then, let him consider how slow a mo∣tion that is, in respect of what 'tis possible a body may par∣ticipate of: and he may safely conclude, that 'tis no wonder though the motion of light be not descried; and that indeed no argument can be made from thence, to prove that light is not a body.

But, let us examine this consideration a little further, and compare it to the motion of the earth or heavens. Let the ap∣pearing circle of the fire be some three foot Diameter, and the

time of one entire circulation of it be the sixtieth part of a mi∣nute; of which minutes there are 60. in an hour; so that, in a whole day, there will but be 86400. of these parts of time. Now, the Diameter of the wheel of fire being but of three foot, the whole quantity of space that it moves, in that atome of time, will be at the most ten foot, which is three paces and a foot; of which parts there are near eleven millions, in the compass of the earth: so that, if the earth be moved round in 24. hours, it must go near 130. times as fast as the Boy's stick, which by its swift motion deceives our eye. But, if we allow the Sun, the Moon, and the fixed Stars to move; how extreme swift must their flight be, and how imperceptible would their motion be, in such a compass as our sight would reach to? And this being certain, that, whether the earth or they move, the appearances to us are the same; 'tis evident, that, as now they cannot be perceiv'd to move (as peradven∣ture they do not) so it would be the very same in shew to us, although they did move. If the Sun were near us and gal∣lop'd at that rate, surely we could not distinguish between the beginning and ending of his race: but there would appear one permanent Line of light from East to West, without any motion at all; as the Torch seems to make, with so much a slower motion, one permanent immoveable wheel of fire.

But, contrary to this effect, we see that the Sun and Stars, by onely being removed further from our eyes, do cosen our sight so grossely, that we cannot discern them to be moved at all. One would imagine, that so rapid and swift a motion should be perceiv'd in some sort or other, (which; whether it be in the earth or in them, is all one to this pur∣pose.) Either we should see them change their places whiles we look upon them, as Arrows and Birds do, when they fly in the Aire: or else, they should make a stream of light bigger then themselvs, as the Torch doth. But, none of all this happens. Let us gaze upon them so long and so attentively, that our eyes be dazled with looking; and all that while they seem to stand immovable: and our eyes can give us no account of their journey, till it be ended; They discern it not while it is in doing:

So that, if we consult with no better counsellour then them, we may wonder to see that body at night setting in the West, which in the morning we beheld rising in the East.

But, that which seems to be yet more strange is, that these bodies move cross us, and nevertheless are not perceiv'd to have any motion at all: Consider, then, how much easier it is for a thing that moves towards us to be with us before we are aware. A nimble Fencer will put in a thrust so quick, that the ••oil will be in your bosome, when you thought it a yard off: because in the same mo∣ment you saw his point so far distant; and could not dis∣cerne it to move towards you, till you felt the rude salutati∣on it gave you. If then you will compare the body of light, with these others that thus deceive us in regard of motion; you must needs agree it is much rashness to conclude it has no motion, because we cannot discern the succession of it. Con∣sider that it is the subtilest of all the bodies that God has made. Examine the paths of it, which, for the smalness of their thrids, and the extreme divisibility of them, and their pli∣ant application of themseles to whatever hath pores, are al∣most without resistance. Calculate the strange multiplication of it, by a perpetual momentary renovation of its streams. And cast with your self, with what extreme force it springs out and flyes abroad. And, on the other side, reflect how all these things are directly opposite and contrary, in those other great bodies; whose motion nevertheless appears, not to us, till it be done and past. And, when you have well weigh'd all this, you must needs grant, that they, who in this case guided themselves meerely by what appears to their eyes, are ill judgers of what they have not well ex∣amin'd. * 1.66

But, peradventure, some, who cannot all of a sudden be wean'd from what their sence hath so long fed them with, may ask yet further, How it chances that we have no effects of this motion? It shews not it self in the air, coming to us a far off. It stays not a thought or slackens its speed, in flying so vast a space, as is from the Sun to us. In fine, there is no discovery of it.

But, if Galileus his conception be well grounded, that Light∣ning gives us an inkling of its motion, beginning from a little and encreasing to a greater; or, if Monsieur des Cartes his opi∣nion, that it goes slower in refraction, be true: we shall not need to study long for an answer. But, in Galileus his ex∣perience, it may be the breaking of the cloud which receives that succession of motion we see: and, no slowness that light can acquire, by the resistance of the refracting body, can be so great as to make that difference of lines, which Monsieur des Cartes most ingeniously (though, I much doubt, not truly) hath apply'd to yield the reason of refraction; as will appear in our further discourse.

Therefore, these being uncertain, we will, to shew the unreasonableness of this question, suppose there may be some observable tardity in the motion of light; and then ask of them, how we should arrive to perceive it? What sense should we imploy in this discovery? It is true, we are satisfied that sound takes up time in coming to our ears: but it is, because our eyes are nimbler then they, and can perceive, a good way di∣stant, the Carpenters ax falling upon the timber that he hews or the fire flashing out of the cannon, before they hear any news of them: but shut your eyes, or inquire of a blind man; and then neither you nor he can tell, whether those sounds will fill your ears at the very instant they were begotten, or have spent some time in their journey to you. Thus, then, our eyes instruct our ears. But is there any sense quicker than the sight? or means to know, speedier than by our eyes? Or can they see light, or any thing else, until it be with them? We may then assuredly conclude, that its motion is not to be dis∣cern'd as it comes upon us; nor it self to be perceiv'd, till its beams are in our eyes.

But, if there be any means to discover its motion, surely it must be in some medium, through which it must struggle to get, as fire doth through Iron; which, increasing there by de∣grees, at last (when it is red hot) sends beams of light quite through the plate, that, at the first, refused them passage. And it makes to this purpose, that the light-conserving stones, which are gathered in Italy, must be set in the Sun for some while, before they retain light: and the light will appear in them,

when they are brought back into the dark, greater or lesser, (until they come to their utmost period), according as they have been longer or a lesser while in the Sun. And our eyes, the longer they remain in the light, the more dazel'd they are if they be suddenly passed into the dark. And, a curious Expe∣riencer did affirm, that the likeness of any object (but particu∣larly, he had often observ'd it of an iron grate), if it be strong∣ly inlightned, will appear to another, in the eye of him that looks strongly and steadily upon it till he be dazel'd by it; even after he shall have turn'd his eyes from it. And, the wheel of fire could never be made appear to our eye, by the whirling of the firestick we even now spoke of; unless the impression, made by the fire from one place, did remain in the eye, a while after the fire was gone from the place whence it sent that ray. Whence 'tis evident, that light, and the pictures of objects, do require time to settle and to unsettle in a subject. If then light makes a greater impression with time, why should we doubt but the first comes also in time; were our sense so nimble as to perceive it?

But then, it may be objected, that the Sun would never * 1.67 be truly in that place, in which to our eyes it appears to be: because, it being seen by means of the light which issues from it, if that light required time to move in, the Sun (whose motions is so swift) would be removed from the place where the light left it, before that could be with us to give tidings of it. To this, I answer, allowing that peradventure it may be so: Who knows the contrary? Or, what inconvenience would follow, if it be admitted? Indeed, how can it be otherwise? In refraction, we are sure it is so: and therefore at no time, but when the Sun is Perpendicularly over our heads, we can be certain of the contrary; although it should send its light to us in an instant. Unless happily the truth of the case should be, that the Sun doth not move about us, but * 1.68 we turn to his light: and then the objection also loses its aim.

But, the more we press the quickness of light, the more we engage our selves in the difficulty, why light doth not shatter the aire in pieces; as likewise all solid bodies whatever: for, the Masters of Natural Philosophy tells us, that a softer thing

with a great velocity, is as powerfull in effect, when it gives a blow, as a harder thing going slowly: And accordingly expe∣rience teaches us, that a tallow candle, shot in a Gun, will go through a board or kill a man. Wherfore light, having such an infinite celerity, should also have an unresistable force, to pierce and shatter, not onely the air, but even the hardest bo∣dies that are. Peradventure some may think it reasonable to grant the consequence (in the circumstances), since experience teaches us, that the congregation of a little light, by a glasse, will set very solid bodies on fire, and will melt metals in a very short space; which shews a great activity: and the great activity shews a great percussion; burning being effect∣ed by a kind of attrition of the thing burned. And the great force which fire shews in Guns and in Mines (being but a multiplication of the same) evidently convinces that, of its own nature, it makes a stong percussion, when all due cir∣cumstances concur. Whereas it has but little effect if the due circumstances be wanting; as we may observe in the insensible burning of so rarified a body as pure spirit of wine converted into flame.

But, we must examine the matter more parrticularly, and seek the cause, why a violent effect doth not always appear, wherever light strikes. For which we are to note, that three things concur to make a percussion great: The big∣ness, the density, and the celerity of the body moved. Of which three, there is onely one in light; to wit, celerity: for it has the greatest rarity, and the rays of it are the smallest par∣cels of all natural bodies, and therfore, since only celerity is considerable in the account of lights percussions, we must exa∣mine what celerity is necessary, to make the stroke of a ray sen∣sible. First then, we see that all the motes of the aire, nay even feathers and straws, do make no sensible percussion when they fall upon us: therefore we must in light have, at the least, a cele∣rity that may be, to the celerity of the straw falling upon our hand (for example,) as the density of the straw is to the density of light; that the percussion of light may be in the least degree sensible. But, let us take a corn of gunpowder instead of a straw (between which there cannot be much difference): and then, putting that the density of fire is, to the density of Gunpowder, as

1. to 125000. and that the density of the light we have here in the earth is, to the density of that part of fire which is in the Suns body, as the body of the Sun is to that body which is called Orbis magnus (whose Semidiameter is the distance be∣tween the Sun and the Earth), which must be in subtriple proportion of the Diameter of the Sun to the Diameter of the great Orb; it follows that 125000. being multiplyed by the proportion of the great Orb to the Sun (which Galileo tells us is as 106000000. to one) will give a scantling of what de∣gree of celerity light must have, more then a corn of Gun∣powder, to recompence the excess of weight which is in a corn of Gunpowder, above that which is in a ray of light, as big as a corn of Gunpowder. Which will amount to be much greater than the proportion of the Semediameter of Orbis magnu•• to the Semidiameter of the corn of Gunpowder: for if you reckon five grains of Gunpowder to a Barly-corns breadth, and 12. of them in an inch, and 12. inches in a foot, and 3. feet in a pace, and 1000. paces in a mile, and 3500. miles in the Semidiameter of the earth, and 1208. Semidiamiters of the earth in the Semidiameter of the Orbis magnus, there will be in it but 913 2480000000. grains of Gunpowder; whereas the other calculation makes light to be 13250000000000 times rarer then gunpowder, which is almost ten times a greater proportion then the other. And yet this cele∣rity supplies but one of the two conditions, wanting in light to make its percussions sensible; namely, density. Now, because the same velocity, in a body of a lesser bulk, doth not make so great a percussion as it doth in a bigger body, and that the little∣ness of the least parts of bodies follows the proportion of their rarity; this vast proportion of celerity must again be drawn in∣to it self, to supply for the excess in bigness that a corn of gun∣powder hath over an atome of light: and the product of this multiplication will be the celerity required to supply for both defects. Which evidently shews, it is impossible that a ray of light should make any sensible percussion; though it be a body. Especially, considering that sense never takes notice of what is perpetually done in a moderate degree. And therefore, after this minute looking into all circumstances, we need not have diffi∣culty in allowing to light the greatest celerity imaginable, and a percussion proportionate to such a celerity in so rare a body;

and yet not fear any violent effect from its blow unless it be condens'd, and many parts of it be brought together to work as if they were but one.

As concerning the last objection, that, if light were a body, It would be fanned by the wind: we must consider, what is the cause * 1.69 of a thing appearing to be moved; and then examine what force that cause hath in light. As for the first part, we see that, when a body is discern'd now in one place, now in another; then it appears to be moved. And this we see happens also in light; as when the Sun or a candle is carried or moves, the light there∣of, in the body of the Candle or Sun, seems to be moved along with it. And the like is in a shining cloud or comet.

But, to apply this to our purpose: We must note, that the in∣tention of the objection is, that the light which goes from the fire to an opacous body far distant, without interruption of its continuity, should seem to be jog'd or put out of its way by the wind that crosses it. Wherein the first failing is, that the Ob∣jector conceives light to send species to our eye from the midst of its line: whereas with a little consideration he may per∣ceive, that no light is seen by us but that which is reflected from an opacous body to our eye; so that the light he means in his objection is never seen at all. Secondly, 'tis manifest that the light which strikes our eye, strikes it in a straight line, and seems to be at the end of that straight line, wherever that is; and so can never appear to be in another place: but, the light, which we see in another place, we conceive to be another light. Which makes it again evident, that the light can never ap∣pear to shake, though we should suppose that light may be seen from the middle of its line; for no part of wind or air can come into any sensible place in that middle of the line with such speed, that new light from the sourcce doth not illuminate it sooner then it can be seen by us: wherefore it will appear to us illuminated, as being in that place; and therefore the light can never appear shaken. And lastly, it is easier for the air or wind to destroy the light, then to remove it out of its place; where∣fore, it can never so remove it out of its place, as that we should see it in another place: But, if it should remove it, it would wrap it up within it self and hide it.

In conclusion, after this long dispute concerning the nature

of light: If we consider well what hath been said on both sides, * 1.70 (to which much more might be added, but that we have already trespassed in length, and I conceive enough is said to decide the matter) an equal judge will find the ballance of the question to hang upon these termes; that, to prove the nature of light to be material & corporeal, are brought a company of accidents. well known to be the proprieties of quantitie or bodies, and as well known to be in light. Even so far as that 'tis manifest, light in its beginning, before it be dispersed, is fire; and if again it be gathered together, it shews it self again to be fire. And, the receptacles, of it are the receptacles of a body: being a multitude of pores, as the hardness and coldness of transparent things do give us to understand; of which we shall hereafter have occasion to discourse.

On the contrary side, whatever arguments are brought, a∣gainst lights being a body, are only negative. As, that we see not any motion of light; that we do not discern where the con∣fines are between light and air; that we see not room for both of them, or for more lights to be together; and the like: which is to oppose negative proofs against affirmative ones; and to build a doctrine upon the defect of our senses; or upon the like∣ness of bodies which are extremely unlike, expecting the same effects from the most subtile as from the most gross ones. All which, together with the authority of Aristotle & his followers, have turned light into darkness, and made us almost deny the light of our own eyes.

Now then, to take our leave of this important question; let us return to the principles from whence we began, and consider * 1.71 that, Seeing Fire is the most rare of the Elements, and very dry; and that out of the former it hath, that it may be cut into very small pieces, and out of the later, that it conserves its own fi∣gure, and so is apt to divide what ever fluid body: and joyning to these two principles, that it multiplies extremely in its source: It must of necessity follow, that it sends out in great multitudes little small parts, into the air and other bodies circumfused, with great dilatation, in a spherical manner: And likewise, that these little parts are easily broken; and, new ones still following the former, are still multiplyed in straight lines from the place where they break. Out of which 'tis evi∣dent

that, of necessity, it must, in a manner, fill all places, and that no sensible place is so little, but that fire wil be found in it, if the medium be capacious. As also, that its extreme least parts will be very easily swallow'd up in the parts of the air, which are humid; and, by their enfolding, be as it were quite lost, so as to lose the appearance of fire. Again, that, in its reflections, it will follow the nature of grosser bodies, and have glidings like them; which is that we call refractions. That little streamings from it will cross one another in excessive great numbers, in an unsensible part of space, without hindering one another. That its motion will be quicker then sense can judge of; and there∣fore will seem to move in an instant, or to stand still as in a stagnation. That, if there be any bodies so porous with little and thick pores, as that the pores arrive near to equalling the substance of the body; then, such a body will be so fill'd with these little particles of fire, that it will appear as if there were no stop in its passage, but were all filled with fire: and yet, many of these little parts will be reflected. And, whatever qualities else we find in light, we shall be able to derive them out of these principles; and shew that fire must of necessity do what experience teaches us that light doth. That is, to say in one word, it will shew us that fire is light. But, if fire be light, then light must needs be fire. And so we leave this matter.

CHAP. IX. Of Local motion in common.

THough, in the fifth Chapter, we made only earth the pre∣tender * 1.72 in the controversie aginst fire, for superiority in activity; (and, in very truth, the greatest force of gravity ap∣pears in those bodies which are eminently earthy): neverthe∣less, both water and air (as appears out of the 4. Chapter of the Elements) do agree with earth in having gravity; and gravity, is the chief virtue to make them efficients. So that, upon the mat∣ter, this plea is common to all the three Elements.

Wherfore, to explicate this virtue, wherby these three weighty Elements work; let us call to mind what we said in the beginning of the last Chapter, concerning local motion: to wit, that, according as the body moved, or the divider, did more and more enter into the divided body; so, it joyn'd it self to

some new parts of the Medium or divided body, and did in like manner forsake others. Whence it happens that in every part of motion, it possesses a greater part of the Medium then it self can fill at once. And because, by the limitation and confinedness of every magnitude to just what it is, and no more, 'tis impossi∣ble that a lesser body should at once equalize a greater; it followes, that this division or motion, whereby a body attains to fill a place bigger then it self, must be done successively; that is, it must first fill one part of the place it moves in, then another, and so proceed on, till it have measur'd it self with every part of the place, from the first beginning of the line of motion to the last period of it where the body rests.

By which discourse it is evident, that there cannot in nature be a strength so great, as to make the least or quickest moveable that is to pass in an instant, or all together; over the least place that can be imagin'd: for, that would make the moved body (re∣maining what it is, in regard of its bigness) to equallize and fit a thing bigger then it is. Therfore it is manifest, that motion must consist of such parts as have this nature, that whiles one of them is in being, the others are not yet: and, as by degrees every new one comes to be, all the others that were before do vanish and cease to be. Which circumstance accompanying motion, we call Succession.

And, whatever is so done is said to be done in time, which * 1.73 is the common measure of all succession, For, the change of situ∣ation of the Stars, but especally of the Sun and Moon, is observ'd, more or less, by all mankind; and appears alike to every man: and (being the most known, constant, and uniform succession that men are used to) is, as it were by nature it self, set in their way and offer'd them, as fittest to estimate and judge all other particular successions; by comparing them both to it, and among themselves by it. And, accordingly, we see all men naturally measure all other successions, and express their quantities, by comparing them to the revolutions of the Heavens; for, dayes, houres, and yeares, are nothing else but they, or some determinate parts of them; to some of which all other motions and successions must of necessity be refer'd, if we will measure them. And thus we see, how all the mystery of applying time to particular motions is nothing else, but the

considering how far the Agent that moves the Sun causes it to go on in its journey, whiles the Agent that moves a particular body causes it to perform its motion.

So that 'tis evident, that Velocity; is the effect of the super∣proportion * 1.74 of the one Agent over a certain Medium; in respect of the proportion which another Agent hath to the same Medi∣um. And, therefore, Velocity is a quality by which One succes∣sion is intrinsically distinguishd from Another: though our ex∣plication uses to include time in the notions of velocity and tardity. Velocity, then, is the effect (as we said) of more strength in the Agent. And, having before expressed, that ve∣locity is a kind of density; we find that this kind of density is an excellency in succession: as permanent density is an excel∣lency in the nature of Substance; though, an imperfection in the nature of Quantity, (by which we see, that quantity is a kind of base alloy added to substance.) And out of this it is evi∣dent that, by how much the quicker the motion is in equall Me∣diums, by so much the agent is the perfecter which causes it to so quick. Wherfore, if the velocity should ascend so much, as to admit no proportion between the quickness of the one and the tardity of the other, all other circumstances being even, excepting the difference of the Agents; then there must be no proportion between the Agents. Nor indeed can there be any proportion between them, though there were never so many differences in other circumstances; as long as those differences be within any proportion. And consequently, you see that, if one Agent be supposed to move in an instant, and another in time; whatever other differences be in the bodies moved and in the Mediums, nevertheless the agent which causes motion in an instant will be infinite, in respect of the agent which moves in time. Which is impossible: it being the nature of a body, that greater quantity of the same thing hath greater virtue, then a less quantity hath; and therfore, for a body to have infinite vir∣tue, it must have infinite magnitude.

If any should say the contrary; affirming the infinite virtue may be in a finite body: I ask, whether in half that body (were it divided) the virtue would be infinite or no? If he acknowledge that it would not; I infer thence, that neither in the two parts together there can be infinite virtue: for two finites cannot com∣pose

and make up one infinite, But, if he will have the virtue be infinite in each half; he therin allows that there is no more virtue in the whole body then in one half of it: which is against the nature of bodies. Now, that a body cannot be infinite in greatness is proved, in the Second Knot of Mr. White's first Dia∣logue. De Mundo. And thus it is evident, that, by the virtue of pure bodies, there can be no motion in an instant.

On the other side it followes, that there cannot be so little a force in nature, but that, giving it time enough, it will move * 1.75 the greatest weight that can be imagined: For, the things we treat of, being all of them quantities, may, by Division and Multiplication, be brought to equality. As for example; Sup∣posing the weight of a moveable to be a million of pounds; and that the mover is able to move the millioneth part of one of those pounds, in a million of yeares, the millioneth part of a pace, through a Medium of a certain rarity: seeing yeers may be multiplied so, as to equalize the force of this mover, to the weight of the moveable: it follows clearly, that this force may move the whole weight of a million of pounds, through the de∣termined Medium, in a determinate number of millions of years, a million of paces. For, such a force is equal to the required effect; and by consequence, if the effect should not follow, there would be a compleat cause put, and no effect re∣sult from it.

But peradventure 'tis needful to illustrate this point yet fur∣ther. Suppose then a weight never so great to be A, and a force never so little to be B. Now, if you conceive that some other force moves A, you must withall conceive it moves A some space; since all motion implies necessarily that it be through some space. Let that space be CD. And, because a body cannot be moved a space in an instant, but requires some time, to have its motion perform'd in; it follows, that there must be a deter∣min'd time, in which the conceiv'd force must move the weight A through the space CD. Let that time be EF. Now, then, this is evident, that 'tis all one to say, that B moves A; and to say, that B moves A, through a space, in a time; so that, if any part of this be left out, it cannot be understood that B moves A. Therfore to express particularly the effect which B is to do upon A, we must say, B must move A a certain

space in a certain time. Which being so, we may in the next place consider, that this effect of moving A may be diminish'd two waies, either because the space 'tis to be moved in is lessened; or the time taken up in its motion is encreas'd: for, as it is a greater effect, to move A through the space CD in a less time then EF, so it is a less effect to move the same A through the space CD in a greater time then EF; or through a less space then CD in the time EF. Now then, this being suposed, that it is a less effect to move A through CD in a greater time then EF: it follows also, that a lesser virtue is able to move it through CD in a greater time then EF, then the virtue which is requir'd to move it through the same space in the time EF. Which if it be once granted (as it cannot be denied), then multiplying the time, as much as the virtue or force required to move A through CD in the time EF is greater then the force B; in so much time the force B will be able to move A through CD. Which discourse is evident, if we take it in common terms: but, it be applied to action, wherin physical accidents intervene; the artificer must have the judgment to provide for them, ac∣cording to the nature of his matter.

Upon this last discourse hangs the Principle which governs * 1.76 Mechanicks, to wit, that the force and the distance of weights counterpoysing one another ought to reciprocal: That is, by how much the one weight is heavier then the other, by so much must the distance of the lighter, from the fixed point upon which they are moved, be greater then the distance of the greater weight from the same point. For 'tis plain, that the weight which is more distant must be moved a greater space, then the nearer weight; in the proportion of the two distances: Wherfore, the force moving it must carry it in a velocity of the said proportion to the velocity of the other; And consequently the Agent, or mover, must be in that proportion more power∣full then the contrary mover. And, out of this practise of Geo∣metricians in Mechanicks, (which is confirmd by experience) 'tis made evident that, if other conditions be equal, the excess of so much Gravity will make so much Velocity: and so much ve∣locity, in proportion, will recompence so much gravity. * 1.77

Out of the precedent Conclusions another follows: which is, that nothing receds from quiet or rest, and attains a great

degree of Celerity, but it must pass through all the degrees of Celerity that are below the obtain'd degree. And the like is, in passing from any lesser degree of velocity to a greater; because it must pass through all the intermediate degrees of velocity. For, by the declaration of velocity, which we have even now made, we see, that there is as much resistance in the Medium to be overcome with speed, as there is for it to be overcome in re∣gard of the quantity, or line of extent of it: because (as we have said) the force of the Agent in counterpoises ought to be encreas'd, as much as the line of extent of the Medium, which is to be overcome by the Agent in equal time, exceeds the line of extent of the other Medium, along which the resistant body is to be moved. Wherfore, it being proved that no line of extent can be overcome in an instant; it follows, that no defect of ve∣locity, which requires as great a superproportion in the cause, can be overcome likewise in an instant.

And, by the same reason, by which we prove that a moveable cannot be drawn in an instant from a lower degree of velocity to a higher, 'tis with no less evidence concluded, that no de∣gree of velocity can be attain'd in an instant: For, divide that degree of velocity into two halfs, and if the Agent had over∣come the one half, he could not overcome the other half in an instant; much less therfore is he able to overcome the whole (that is, to reduce the moveable from quiet to the said degree of velocity) in an instant.

Another reason may be, because the movers themselvs (such movers as we treat of here) are Bodies likewise moved, and consist of parts: wherof not every one part, but a competent number of them, makes the moving body a fit Agent, able to move the proposed body in a proposed degree of celerity. Now, this Agent meeting with resistance in the moveable, and not being in the utmost extremity of density, but condensable yet further, (because it is a bo∣dy); and every resistance (be it never so small) works something upon the mover (though never so hard) to condense it: the parts of the mover, that are to over∣come this resistance in the moveable, must (to work that effect) be condens'd and brought together as close as is needful, by this resistance of the moveable to the mo∣ver;

and so, the remote parts of the mover become nearer to the moveable, which cannot be done but successively, because it enclud's local motion. And, this application being likewise divisible, and not all the parts flocking together in an instant to the place where they are to exercise their power: it follows, that, whiles there are fewer moving parts knit together, they must needs move less and more weakly, then when more or all of them are assembled and appled to that work. So that, the mo∣tive virtue encreasing thus, in proportion to the multiplying of the parts applied to cause the motion; of necessity, the effect (which is obedience to be moved, and quickness of motion, in them oveable) must do so too: that is, it must from nothing, or from rest, passe through al the degrees of celerityun, till it arrive to that which all the parts together are able to cause.

As for example, when with my hand I strike a ball; till my hand touches it, 'tis in quiet: but then it begins to move; yet with such resistance, that, although it obey in some measure the stroke of my hand, nevetiheless it presses the yeelding flesh of my palm, backwards towards the upper and bony part of it. That part then overtaking the other, by the continu'd motion of my hand; and both of them joyning together to force the ball away; the impulse becomes stronger, then at the first touching of it. And, the longer it presses upon it, the more the parts of my hand condense and unite themselvs to excercise their force; and the ball therfore must yeeld the more: and consequent, the motion of it 〈◊〉〈◊〉 quicker and quicker, till my hand parts from it. Which condensation of the parts of my hand encreasing successively, by the parts joyning closer to one another, the velocity of the balls motion (which is an effect of it) must also encrease proportionably therto. And in like manner, the motion of my hand and arm must grow quicker and quicker; and pass all the degrees of velocity between rest and the utmost degree it attains unto: For seeing they are the Spirits swelling the Nervs, that cause the arms motion, (as we shall hereafter shew); upon its resistance, they flock from o∣ther parts of the body to evercome that resistance. And since their journey thither requires time to perform it in; and the nearest come first: it must needs follow, that, as they grow more and more in number, they must more

powerfully overcome the resistance, and consequently, encrease the velocity of the motion, in the same proportion as they flock thither; till it attain that degree of velocity, which is the ut∣most period that the power which the Agent hath to overcome the resistance of the medium can bring it self to. Between which and rest, or any other inferiour degree of velocity, there may be design'd infinite intermediate degrees; proportionable to the infinite divisibility of time, and space, in which the mover moves. Which degrees arise out of the reciprocal yeilding of the medium: And that is likewise divisible in the same infinite proportion.

Since then, the power of all natural Agents is limited, the mo∣ver (be it never so powerful) must be confined to observe these proportions, and cannot pass over all these infinite designable degrees in an instant; but must allot some time (which hath a like infinity of designable parts) to ballance this infinity of de∣grees of velocity: and so consequently, it requires time, to attain to any determinate degree. And therfore cannot recede imme∣diately from rest to any degree of celerity, but must necessarily pass through all the intermediate ones.

Thus 'tis evident that all motion which hath a beginning must of necessity increase for some time. And, since the works of nature are in proportion to their causes, it follows that this en∣crease is in a determinate proportion: Which Galileus (to whom we owe the greatest part of what is known concerning motion) teaches us how to find out; and to discover what de∣gree of celerity any movable, that is moved by nature, has, in a∣ny determinate part of the space it moves in.

Having settled these conditions of motion; we shall do well in * 1.78 the next place to enquire after the causes of it: as well in the bo∣dy moved, as also in the mover that occasions the motion. And, because we have already shewed, that local motion is nothing in substance but division: we may determine that those causes w^ch cōtribute to division, or resist it, are the causes which make or resist local motion. It has also been said, that Density has in it a power of dividing; and that Rarity is the cause of being divided; likewise we have said that fire, by reason of its smal parts, intow^ch it may be cut (which makes them sharp) has also an eminence in dividing: So that we have two qualities, density and tenuity

or sharpness, which concur actively to division. We have told. * 1.79 you also how Galileus has demonstrated, that a greater quantity, of the same figure and density, has a priviledge of descending faster than a lesser. And that priviledge consists in this, that the proportion of the superficies to the body it limits (which pro∣portion the greater it is, the more it retards) is less in a greater bulk than in a smaller.

We have therfore three conditions concurring to make the motion more efficacious: namely, the density, the sharpness, and the bulk of the movable: and more then these three we cannot expect to find in a moved body. For, quantity hath but three de∣terminations: one, by density & rarity; of which density is one of the three conditions: another, by its parts; as by a foot, a span, &c. and in this way we have found that the greater excells the lesser: the third and last is, by its figure, and in this we find that subtile or edged quantities do prevail over blunt ones. Seeing, therfore, that these three determinations be all that are in quantity; there can be no more conditions in the body moved, (which of neces∣sity is a finite quantity), but the three named.

And, as for the medium which is to be divided, there is only rarity and density (the one, to help; the other to hinder) that re∣quire consideration, on its side: For, neither figure, nor littleness and greatness, do make any variation in it. And as for the Agent, it is not as yet time, before we have look'd further into the na∣ture of motion, to determine his qualities.

Now then, let us reflect how these three conditions do all a∣gree in this circumstance, that they help nothing to division; un∣less the body in which they are to be moved and press'd against * 1.80 the body that is to be divided: so that we see no principle to perswade us, that any body can move it self towards any deter∣minate part or place of the universe, of its own intrinsecal in∣clination. For, besides that the learned Author of the Dialogues de Mundo (in his third Dialogue, and the second Knot) hath de∣monstrated, that a body cannot move unless it be moved by some extrinsecal Agent; we may easily frame to our selves a conceit, how absurd it is to think that a body, by a quality in it, can work upon it self: as if we should say, that rarity (which is but more quantity) could work upon quantity; or that figure (which is but that the body reaches no further) could work

upon the body: and in general, that the manner of any thing can work upon that thing whose manner it is. For Aristotle and St. Thomas, and their Intelligent Commentators, declaring the notion of Quality, tell us, that to be a Quality is nothing else but to be the determination or modification of the thing whose quality it is.

Besides, the natural manner of operation is, to work accord∣ing to the capacity of the subject: but, when a body is in the midst of an uniform medium or space, the subject is equally pre∣par'd on all sides to receive the action of that body. Wher∣fore (though we should allow it a force to move), if it be a na∣tural Agent and have no understanding, it must work indiffe∣rently on all sides, and by consequence, cannot move on any side. For, if you say, that the Agent in this case (where the me∣dium is uniform) works rather upon one side than upon ano∣ther; it must be because this determination is within the Agent it self, and not out of the circumstant dispositions: which is the manner of working of those substances that work for an end of their own; that is, of understanding creatures, and not of natu∣ral hodies.

Now, he that would exactly determine what motion a body has, or is apt to have, determining by supposition the force of * 1.81 the Agent, must calculate the proportions of all these three con∣ditions of the movable, and the quality of the medium; which is a proceeding too particular for the intention of our discourse. But, to speak in common, it will not be amiss to examine in what proportion motion doth increase: since we have concluded that all motion proceeds from quiet, by a continual encrease, Galile∣us (that miracle of our age, and whose wit was able to discover whatever he had a mind to employ it about) hath told us that na∣tural motion encreases, in the proportion of the odd numbers. Which, to express by example, is thus: suppose that in the go∣ing of the first yard it has one degree of velocity, then in the going of the second yard it will have three degrees, and in going of the third it will have five; and so onwards, still adding two to the degrees of the velocity, for every one to the space. Or, to ex∣press it more plainly; if in the first minute of time it goes one yard of space, then in the next minute it will go three yards, in the third it will go five, in the fourth seaven; and so forth.

But, we must enlarge this proposition to all motions; as we have done the former, of the encrease it self in velocity: because the reason of it is common to all motions. Which is, that all motion (as may appear out of what we have formerly said) proceeds from two causes: namely, the Agent or the force that moves; and the disposition of the body moved, as it is composed of the three qualities we lately explicated. In which is to be noted, that the Agent doth not move simply by its own virtue, but applyes also the virtue of the body moved, which it hath, to divide the medium when it is put on. As when we cut with a knife, the effect proceeds from the knife press'd on by the hand; or, from the hand as applying and putting in action the edge and cutting power of the knife, Now this, in Phy∣sicks and Nature, is clearly parallel to what, in Geometry and A∣rithmatick the Mathematicians call drawing one number or one side into another; for as, in Mathematicks, to draw one number into another is to apply the number drawn to every part of the number into which it is drawn (as, if we draw three into seven, we make twenty one, by making every unity or part of the number seven to be three; and the like is of lines, in Geo∣metry); So, in the present case, to every part of the hands mo∣tion, we add the whole virtue of the cutting faculty which is in the knife, and, to every part of the motion of the knife, we add the whole pressing virtue of the hand. Therfore the encrease of the effect, proceeding from two causes so working, must also be parallel to the encrease of the quantities arising out of the like drawing in Mathematicks. But in those, 'tis evident that the encrease is according to the order of the odd numbers; and therfore it must in our case be the like: that is, the encrease must be in the said proportion of odd numbers, Now, that in those the encrease proceeds so, will be evident, if you consider the encrease of an Equicrure Triangle; which, because it goes up∣on a certain proportion of length and breadth, if you compare the encreases of the whole Triangle (that gains on each side) with the encreases of the perpendicular (which gains only in length), you will see that they will proceed in the foresaid pro∣portion of odd numbers.

Which will be better understood, if we set down the demon∣stration of it. Let the Equicrure Triangle be ABC: and, from the

point A, draw the line AD

[illustration]

perpendicular to the line BC, and let it be divided in to three equal parts by the lines EF and GH, in the points I & K. And I say, that because the line AK, is twice as long as the line AI, therfore the trapezium, EFHG, is thrice as big as the triangle AEF. For, as AK is to AI, so is GH to EF: but the triangle AGH is, to the triangle AEF; in a double proportion of the line GH to the line EF; which being double the proportion of one tri∣angle to the other must be fourfold: so that subtracting the tri∣angle AEF, the trapezium EFGH remains thrice as big as it. And thus the whole triangle gets an encrense of three, whiles the perpendicular is encreased but one, to make his length two. Which when it comes to three, the trapezium, GHCB, that con∣tains the third division of the perpendicular, becomes five times as big as the triangle AEF. For, since the line AD is three times as long as the line AI; and the line BC is three times as long as EF; it follows, that the triangle ABC is nine times as big as the triangle AEF: but AGH is four times as big as AEF: therfore subtracting it from the whole triangle ABC, it leaves the trapezium GHCB five times as big as the first triangle AEF. Which proposition is very ingeniously set down by the learned Monsieur Gassendi, in his first Epistle, Demotu impresso a m••tore translato, to the same purpose for which we bring it. Though we do not here wake use of this Scheme and way of demonstration; because we had fallen upon this before his book came abroad: and therfore we only note his, to direct the Reader to it, who peradventure may like his better, than ours. Howbeit we do not conceive that he hath, in his discourse there, arrived to the true reason of the effect we search into: as may appear by what we * 1.82 have already deliver'd.

But, we must not imagine that the velocity of motion will always encrease thus, for as long as we can fancy any motion: but, when it is arrived to the utmost period that such a moveable with such causes is capable of, then it keeps constantly

the same pace, and goes equally and uniformly at the same rate. For since the density of the moveable, & the force of the Agent moving it, (which two cause the motion) have a limited propor∣tion to the resistance of the medium, how yeilding soever it be: it must needs follow, that when the motion is arrived to that height which arises out of this proportion, it cannot exceed it, but must continue at that rate; unless some other cause give yet a greater impulse to the movable, For, velocity consisting in this, that the movable cuts through more of the medium in an equal time; 'tis evident, that in the encrease of velocity, the resistance of the medium which is overcome by it, grows greater and greater, and by little and little gains upon the force of the Agent; so that the superproportion of the Agent grows still lesser and lesser, as the velocity encreases; and therfore at the length they must come to be ballanced, and then the ve∣locity can encrease no more.

And the reason of the encrease of it, for a while at the begin∣ning, is because, coming from rest, it must pass through all the intermediate degrees of velocity, before it can attain to the height of it; which requires time to perform, and therfore falls under the power of our sense to observe. But, because we see it do so for some time, we must not therfore conclude, the na∣ture of such motion is still to encrease, without any period or limit; like those lines that perpetually grow nearer; and yet can never meet: for, we see our reason, examining the causes of this velocity, assures us that, in continuance of time and space, it may come to its height, which it cannot exceed.

And there would be the pitch, at which distance weights be∣ing let fall would give the greatest strokes and make greatest impressions. 'Tis true that Galileus and Mersenius (two exact experimenters) do think they find this verity by their experien∣ces: But, surely that is impossible to be done. For, the encrease of velocity, being in a proportion ever diminishing, must of ne∣cessity come to an insensible increase in proportion, before it ends: for, the space which the movable goes through, is still en∣creased, and the time, wherin it passes through that space, re∣mains still the same little one, as was taken up in passing a less space immediately before; & such little differences, of great spa∣ces passed over in a little time, come soon to be undiscernible by sense. But reason (which shews us that, if velocity never ceased

from encreasing, it would in time arive to exceed any particular velocity, and, by consequence, the proportion which the mover has to the medium; because of the adding still a determinate part to its velocity) concludes plainly, that it is impossible mo∣tion should increase for ever, without coming to a period.

Now the impression which falling weights make is of two kinds: for, the body into which impression is made either can * 1.83 yield backward, or it cannot. If it can yield backward, then the impression made is a motion: as we see a stroke with a Racket up∣on a Ball, or with a Pail-mail beetle upon a Bowl, makes it flie from it. But, if the strucken body cannot yield backwards, then it makes it yield on the sides: And this, in divers matters; for, if the smitten body be drie and brittle, 'tis subject to break it and make the pieces flie round about; but if it be a tough body, it squeeses it into a larger form.

But, because, the effect, in any of these ways, is eminently grea∣ter than the force of the Agent seems to be; 'tis worth our la∣bour to look into the causes of it. To which end, we may remem∣ber how we have already declared, that the force of the velocity is equall to a reciprocall force of weight in the virtue movent: wherefore the effect of a blow that a man gives with a hammer depends, on the weight of the hammer, on the velocity of the motion, and on the hand, in case the hand accompanies the blow. But, if the motion of the hand ceases before (as when we throw a thing), then only the velocity and the weight of the hammer remain to be consider'd. However, let us put the hand and weight in one sum, which we may equalize by some other virtue or weight: Then, let us consider the way or space which a weight, lying upon the thing, is to go forwards; to do the same effect in the same time as the percussion doth; and, what excess the line of the blow hath over the line of that way or space, such an excess we must add of equal weight or force, to the weight we had already taken: And, the weight composed of both will be a fit Agent to make the like impression. This Problem was proposed to me by that worthy religious man, Father Mersenius: who is not content with advancing learning by his own industry and labours; but besides, is alwayes (out of his generous affection to verity) inciting others to contribute to the publick stock of it.

He proposed to me likewise this following question, to wit,

why there is required a weight of water in double Geometri∣cal proportion, to make a pipe run twice as fast as it did, or have twice as much water run out in the same time? To which I answer out of the same ground, as before: That because, in running twice as fast, there goes out double the water in every part of time; and again, every part of water goes a double space in the same part of time (that is to say, because double the cele∣rity is drawn into double the water, and double the water into doule the celerity; therfore the present effect is, to the for∣mer effect, as the effect or quadrate of a double line drawn into into it self, is to the effect or quadrate of half the said line drawn into it self. And consequently, the cause of the latter effect (which is the weight then) must be to the cause of the former effect (that is, to the former weight) in the same proportion; namely, as the quadrate of a double line is to the quadrate of half that line. And so you see the reason of what he by experi∣ence finds to be true. Though I doubt not but when he shall set out the treatise which he has made on this subject, the Reader will have better satisfaction.

In the mean while, an experiment which Galileo delivers will confirm this doctrine. He sayes, that, to make the same Pen∣dant go twice as fast as it did, or to make every undulation of it in half the time it did, you must make the line, at which it hangs, double in Geometrical proportion, to the line at which it hang'd before. Whence it follows, that the circle by which it goes is likewise in double Geometrical proportion. And this being certain, that celerity to celerity has the proportion of force, which weight has to weight; 'tis evident that, as in one case, there must be weight in Geometrical proportion, so in theo∣ther case, where only celerity makes the variance, the celerity must be in double Geometrical proportion; according as Ga∣lileo finds it by experience.

But, to return to our main intent; there is to be further noted that, If the subject strucken be of a proportionate cessibility, it seems to dull and deaden the stroke; wheras, if the thing struck∣en be hard, the stroke seems to lose no force, but to work a greater effect. Though indeed the truth be, that in both ca∣ses the effects are equal; but diverse according to the natures of the things that are strucken; for, no force that once is in nature can be lost, but must have its adequate effect one way or other.

Let us then first suppose the body strucken to be a hard body, of no exceeding bigness: in which case, if the stroke light per∣pendicularly upon it, it will carry such a body before it. But, if the body be too great, and have its parts so conjoyn'd that they are weaker then the stroke; in this case the stroke drives one part before it, and so breaks it from the rest. But lastly, if the parts of the strucken body be so easily cessible, as without dif∣ficulty the stroke can divide them; then it enters into such a bo∣dy till it has spent its force. So that now, making up our ac∣count, we see that an equal effect proceeds from an equal force in all the three cases, though in themselves they be far different. But, we are apt to account that effect greater, which is more con∣siderable to us by the profit or damage it brings us. And therefore we usually say, that the blow, which shakes a wall, or beats it down and kills men with the stones it scatters abroad, hath a greater effect then that which penetrates far into a mud wall, and doth little harm: for that innocuousness of the effect makes that, although in it self it be as great as the other, yet 'tis little observ'd or consider'd.

This discourse draws on another: which is to declare how motion ceases. And to sum that up in short, we say that, When * 1.84 motion comes to rest, it decreases and passes through all the degrees of celerity and tardity, that are between rest and the height of that motion which so declines: and that in the pro∣portion of the odd numbers, as, we declared above, it en∣creas'd. The reason is clear; because that which makes a motion cease is the resistance it findes: which resistance is an action of a mover that moves something against the body moved, or something equivalent to such an action; wherefore it must follow the laws that are common to all motions; of which kind those two are that we have expressed in this conclusion. Now, that resistance is a countermotion, or equivalent to one is plain by this that any body which is pressed must needs press again on the body that presses it; wherefore, the cause that hinders such a body from yielding is a force moving that body against the body which presses it. The particulars of all which we shall more at large declare, where we speak of the action and reaction of par∣ticular bodies.

CHAP. X. Of Gravity and Levity; and of Local Motion, commonly term'd Natural.

IT is now time to consider that distinction of motions which * 1.85 is so famous in Aristotle; to wit; that some motions are natu∣ral, others violent: and to determine what may be signified by these terms. For seeing we have said that no body hath a natu∣ral intrinsecal inclination to any place, to which 'tis able to move it self; we must needs conclude that the motion of every body follows the percussion of extrinsecal Agents. It seems therefore impossible that any body should have any motion natural to it self: and, if there be none natural, there can be none violent; and so this distinction will vanish to nothing. But on the otherside, Living creatures manifestly shew na∣tural motions; having natural instruments to perform certain motions: wherefore such motions must of necessity be natural to them: But, these are not the motions we are to speak of; for, Aristotles division is common to all bodies, or at the least to all those we converse with: and particularly to those which are call'd heavy and light; which two terms pass through all the bodies we have notice of.

Therefore, proceeding on our grounds before lay'd, to wit, that no body can be moved of it self; we may determine those motions to be natural to bodies, which have constant causes or percutients to make them always in such bodies; and those violent, which are contrary to such natural motions. Which being suppos'd; we much search out the causes, that so constantly make some bodies descend towards the center or the middle of the earth, & others to rise and go from the cen∣ter: by which the world is subject to those restless motions, that keep all things in perpetual flux, in this changing sphere of a∣ction and passion.

Let us then begin with considering what effects the Sun * 1.86 (which is a constant and perpetual cause) works on in∣feriour bodies, by his being regularly sometimes present and sometimes absent. Observe in a pot of water hanging over a fire, how the heat makes some parts of the water ascend, and others to supply the room by descending; so

that, as long as it boyls; 'tis in a perpetual confused mo∣tion up and down. Now, having formerly concluded that fire is light, and light is fire; it cannot be doubted but that the Sun serves instead of fire to our Globe of Earth and water, (which may be fitly compared to the boyling pot;) and all the day long draws vapours from those bodies that his beams strike upon. For, he shooting his little darts of fire, in multitudes and in continued streams from his own center, a∣gainst the Python, the earth we live on; they there overtake one another and cause some degrees of heat, as far as they sink in. But, not being able (by reason of their great expansi∣on in their long journey) to convert it into their own nature and set it on fire, (which requires a high degree of condensati∣on of the beams); they but pierce and divide it very subtilly, and cut some of the outwardparts of it into extreme little a∣tomes. To which sticking very close, and being in a man∣ner incorporated with them (by reason of the moisture that is in them), they, in their rebound back from the earth, carry them along with them; like a ball that, struck against a moist wall, in its return from it, brings back some of the mortar sticking upon it. For, the distance of the Earth from the Sun is not the utmost period of these nimble bodie's flight; so that, when by this solid body they are stop'd in their course for∣wards on, they leap back from it, and carry some little parts of it with them: som of them a farther, some of them a shorter jour∣ney; according to their littleness and rarity make them fit to as∣cend. As is manifest by the consent of all Authors that write of the Regions of the Air: who determine the Lower Region to reach as far as the reflection of the Sun; and conclude this Re∣gion to be very hot.

For, if we mark how the heat of fire is greatest, when it is in∣corporated in some dense body, (as in Iron or in Sea-coal); we shall easily conceive that the heat of this Region proceeds mainly, out of the incorporation of light with those little bo∣dies which stick to it in its reflection. And, experience testifies the same, both in our soultry days, which we see are of a gross temper, and ordinarily go before rain, as also in the hot Springs of extreme cold countrys, where the first heats are unsufferable, which proceed out of the resolution of humidity congeal'd: & in

hot winds (which the Spaniards call Bochornos, from Boca de horno, by allusion to the breathing stream of an Oven when it is open'd), which manifestly shew that the heat of the Sun is incorporated in the little bodies, which compose the steam of that wind. And, by the principles we have already laid, the same would be evident; though we had no experi∣ence to instruct us; for, seeing that the body of fire is dry, the wet parts (which are easiest resolved by fire) must needs stick to them, and accompany them in their return from the earth.

Now, whiles these ascend, the air must needs cause others * 1.87 that are of a grosser complexion to descend as fast, to make room for the former, and to fill the places they left; that there may be no vacuity in nature. And, to find what parts they are, and from whence they come, that succeed in the room of light and atomes glew'd together that thus ascend; we may take a hint from the Maxime of the Opticks, that Light reflecting makes equal angles: whence, supposing the Superficies of the earth to be circular, it will follow that a Perpendicular to the center passes just in the middle between the two rayes, the in∣cident and the reflected. Wherefore, the air between these two rayes, and such bodies as are in it, being equally pressed on both sides; those bodies which are just in the middle are nearest, and likeliest to succeed immediately, in the room of the light and atomes which ascend from the Superficies of the earth: and their motion to that point is upon the Perpendicular. Hence 'tis evident, that the Air and all such bodies as descend to supply the place of light and atomes, which ascend from the Earth, descend perpendicularly towards the center of the earth.

And again, such bodies as, by the force of light being cut from the earth or water, do not ascend in form of light, but incorporate a hidden light and heat within them, (and thereby are rarer then these descending bodies), must of necessity be lifted up, by the descent of those denser bodies that go downwards, because they (by reason of their density) are moved with a greater force. And this lifting up must be in a perpendicular line; because the others, descending on all sides perpendicularly, must needs raise those that are between them

equally from all sides: that is, perpendicularly from the center of the earth. And thus we see a motion set on foot, of some bo∣dies continually descending, and others continually ascending: all in perpendicular lines; excepting those which follow the course of lights reflexion.

Again, as soon as the declining Sun grows weaker or leaves our Horizon, and his beams, vanishing, leave the little hors-men which rode upon them, to their own temper and nature (from whence they forced them: they, finding themselvs, surrounded by a smart descending stream, tumble down again in the night, as fast as in the day they were carried up; and, crowding into their former habitations, exclude those they find had usurped them in their absence. And thus, all bodies within reach of the Suns power, but especially our air, are in perpetual moti∣on: the more rarified ones ascending, and the dense ones de∣scending.

Now then, because no bodies, wherever they be (as we have * 1.88 already shew'd), have any inclination to move towards a particu∣lar place, otherwise then as they are directed and impel'd by extrinsecal Agents: let us suppose that a body were placed at liberty in the open air. And then, casting whether it would be moved from the place we suppose it in; and which way it would be moved; we shall find, it must of necessity happen that it shall descend and fall down, till it meet with some other gross body to stay and support it. For, though of it self it would move no way; yet, if we find that any other body strikes effica∣ciously enough upon it, we cannot doubt but it will move that way which the striking body impels it. Now, it is strucken up∣on on both sides (above and below), by the ascending and the descending atoms; the rare ones striking upon the bottome of it and driving it upwards, and the denser ones pressing upon the top of it and bearing it downwards. But, if you compare the the impressions the denser atoms make with those that proceed from the rare ones; 'tis evident, the dense ones must be the more powerful; and therfore will assuredly determine the motion of the body in the air that way they go, which is down∣wards.

Nor need we fear, lest the littlenessof the agents, or the fee∣bleness of their stroaks, should not be sufficient to work this

effect; since there is no resistance in the body it self, and the air is continually cut in pieces by the Sun-beams, and by the mo∣tions of little bodies; so that the adhesion to air of the body to be moved, will be no hind'rance to this motion: especially, con∣sidering the perpetual new percussions, and the multitude of them; and how no force is so little but that, with time and mul∣tiplication, it will overcome any resistance.

But, if any man desires to look on, as it were at one view, the whole chain of this doctrine of Gravity: let him turn the first * 1.89 cast of his eyes on what we have said of fire, when we ex∣plicated the nature of it; To wit, that it begins from a little source, and, by extreme multiplication and rarefaction, ex∣tends it self into a great sphere. And then hee's perceive the reason, why light is darted from the body of the Sun with that incredible celerity, wherewith its beams fly to visit the remotest parts of the world: and how, of necessity, it gives motion to all circumstant bodies; since it is violently thrust forward by so extreme rarefaction, and, the further it goes, is still the more ra∣rified and dilated.

Next, let him reflect, how infinitely the quickness of lights motion prevents the motion of a moist body; such an one as air is: and then he wil plainly see, that the first motion, which light is able to give the air must needs be a swelling of that moist ele∣ment, perpendicularly round about the earth. For, the ray descendent, and the ray reflectent, flying with so great a speed, that the air between them cannot take a formal pley any way before the beams of light be on both sides of it: it followes, that, according to the nature of humide things, it must first only swell; for, that is the beginning of motion in them, when heat enters into and works on them. And thus he may confidently resolve himself, that the first motion which light causes in the air will be a swelling of it, between the two rays towards the middle of them; That is, perpendicularly from the surface of the earth.

And, out of this, he will likewise plainly see, that, if there be any other little dense bodies floating in the air, they must like∣wise mount a little, through this swelling and rising of the air. But, that mounting will be no more, then the immediate parts of the air themselvs move: Because this motion is not by way

of impulse or stroke that the air gives those denser bodies; but by way of containing them in it, and carrying them with it; so that it gives them no more celerity, then to make them go with it self, and as parts of it self.

Then, let him consider, that light or fire, by much beating upon the earth, divides some little parts of it from others: wher∣of if any become so small and tractable, as not to exceed the strength which the rays have to manage them, the returning rays will, at their going back, carry away with or drive before them such little atomes as they made or met with; and so fill the air with little bodies cut out of the earth.

After this, let him consider, that, when light caries up an atome with it, the light and the atome stick together and make one ascending body; in such sort as, when an empty dish lies upon the water, the air in the dish makes one descendent body toge∣ther with the dish it self: so that the density of the whole body of air and dish (which, in this case, are but as one body) is to be esteem'd according to the density of the two parts, one of them being allay'd by the other, as if the whole where thrughout of such a proportion of density, as would arise out of the compo∣sition and kneading together the several densities of those two parts. Now then, when these little compounded bodies of light and earth, are carryed up to a determinate height, the parts of fire or light by little and little break away from them: and therby the bulk of the part which is left becoms of a different degree of density (quantity for quantity) from the bulk of the entire atome, when light was part of it; and consequent∣ly it is denser then it was.

Besides, let him consider, that, when these bodies ascend, they go from a narrow room to a large one, that is, from the centre∣wards to the circumference; but, when they come down again, they go from a larger, part to a narrower. Whence it followes, that, as they descend, they draw closer and closer together, and by consequence, are subject to meet and fall in one with ano∣ther: and therby to increase their bulk, and become more powerful in density; not only, by the loss of their fire, but also by the encrease of their quantity. And so 'tis evident, that they are denser coming down, then going up.

Lastly, let him consider, that, those atoms which went up first,

and are parted from their volative companions of fire or light, must begin to come down apace, when other new atoms (which still have their light incorporated with them) ascend to where they are, and go beyond them by reason of their greater levity. And, as the latter atoms come up with a violence and great celerity, so must the first go down with a smart im∣pulse: and by consequence, being more dense then the air in which they are carryed, must of necessity cut their way through that liquid and rare Medium; and go the next way to supply the defect and room of the atoms which ascend, (that is, perpen∣dicularly to the earth) and give the like motion to any body they find in their way, if it be susceptible of such a motion: Which 'tis evident that all bodies are, unless they be strucken by some contrary impulse. For, since a bodies being in a place is nothing else, but the continuity of its outside to the inside of the body that contains it and is its place, it can have no other repugnance to local motion, (which is nothing else but a suc∣cessive changing of place), besides this continuity. Now the na∣ture of density being the power of dividing, and every least power having some force & efficacy, (as we have shew'd above): it follows, that the stroke of every atome (either descending, or ascending) will work somthing upon any body (though ne∣ver so big) it chances to incounter with and strike upon in its way; unless there be as strong an impulse the contrary way to oppose it. But, it being determin'd, that the descending atoms are denser then those that ascend; it follows, that the descen∣ding ones will prevail: And consequently, all dense bodies must necessarily tend downwards to the center (which is to be hea∣vy), if some other more dense body do not hinder them.

Out of this discourse, we may conclude that there is no such * 1.90 thing among bodies, as positive gravity or levity: but that their course upwards or downwards happens to them by the order of nature, which by outward causes gives them an impulse one of these wayes; without which, they would rest quietly wherever they are, as being of themselvs indifferent to any mo∣tion. But, because our words express our notions, and they are fram'd according to what appears to us; when we observe any body to descend constantly towards our earth, we call it heavie; and if it move contrarywise, we call it light.

But, we must take heed of considering such gravity and levity, as if they were Entities that work such effects: since upon exa∣mination it appears, that these words are but short expressions of the effects themselves, the causes whereof the vulgar of man∣kind (who impose names to things) do not consider, but leave that work to Philosophers to examine; whiles they onely observe, what they see done, and agree upon words to express that. Which words neither will, in all circumstances, always, a∣gree to the same thing: for, as cork descends in aire and as∣cends in water; so also will any other body descend if it lights among others more rare then it self, and will ascend if it lights among others that are more dense then it. And we term Bo∣dies light and heavy, only according to the course which we usually see them take.

Now, proceeding further on, and considering how there are * 1.91 various degrees of density or gravity; it were irrational to con∣ceive, that all bodies should descend at the same rate, and keep equal pace with one another, in their journey downwards. For, as two knives, whereof one hath a keener edge then the o∣ther, being press'd with equal strength into like yielding mat∣ter, the sharper will cut deeper then the other: so, if, of two bo∣dies, one be more dense then the others that which is so will cut the air more powerfully, and descend faster then the other: for, in this case density may be compared to the kniefs edge; since in it consists the power of dividing, as we have heretofore de∣termin'd. And therefore, the pressing them downwards by the descending atomes being equal in both (or peradventure great∣er in the more dense body; as anon we shall have occasion to touch); and there being no other cause to determine them that way; the effect of division must be the greater, where the divider is the more powerful: Which, the more dense body is; and * 1.92 therefore cuts more strongly through the resistance of the air; and consequently, passes more swiftly that way 'tis deter∣min'd to move.

I do not mean, that the velocities of their descent shall be in the same proportion to one another, as their densities are: for, besides their density, those other considerations, which we have discours'd of above when we examin'd the causes of velocity in motion, must likewise be ballanced. And out of the

comparisons of all them, not out of the consideration of any one alone, results the differences of their velocities: (nor that neither, but in as much as concerns the consideration of the moveables; for, to make the calculation exact, the Medium must likewise be considered, as by and by we shall declare). For, since the motion depends of all them together, though there should be difference between the moveables in regard of one only, and that the rest were equal; yet the proportion of the difference of their motions must not follow the proportion of their diffe∣rence in that one regard: because, their difference consider'd single in that regard will have one proportion; and with the addition of the other considerations (though alike in both) to their difference in this, they will have another.

As for example, reckon the density of one moveable to be double the density of another moveable; so that in that regard it has two degrees of power to descend, whereas the other has but one: suppose then the other causes of thier descent to be alike in both; and reckon them all three: and then joyn these three to the one which is caused by the density in one of the moveables; as likewise to the two, which is caused by the den∣sity in the other moveable: and you will find that, thus altoge∣ther, their difference of power to descend is no longer in a dou∣ble proportion (as it would be, if nothing but their density were considered) but is in the proportion of five to four.

But, after we have consider'd all that concerns the move∣ables, we are then to cast an eye upon the Medium they are to move in; and we shall find the addition of that decreases the proportion of their difference exceedingly more, according to the cessibility of the Medium: Which, if it be Air, the great disproportion of its weight, to the weight of those bodies which men use to take in making experiences of their descent in that yeelding Medium, will cause their difference of velo∣city in descending to be hardly perceptible. Even as the diffe∣rence of a sharp or dull knife, which is easily perceiv'd in cut∣ting of flesh or bread, is not to be distinguish'd in divi∣ding of water or oyl. And likewise in Weights, a pound and a scruple will bear down a dram, in no sensible propor∣tion of velocity, more then a pound alone would do: and yet, put a pound in that scale in stead of the dram, and then

the difference of the scruple will be very notable. So then, those bodies, whose difference of descending in water is very sensible (because of the greater proportion of weight in water, to the bodies that descend in it), will yield no sensible difference of ve∣locity when they descend in air; by reason of the great dispro∣portion of weight between air and the bodies that descend in it.

The reason of this will clearly shew it self in abstracted pro∣portions: Thus, Suppose air to have one degree of density, and water to have 400 then let the moveable A. have 410 degrees of density; and the moveable B. have 500. Now, compare their motion to one another, in the several mediums of air and wa∣ter: The exuperance of the density of A. to water is 10 degrees, but the exuperance of B. to the same water is 100 degrees; so that B. must have in water swifter then A, in the proportion of 103 to ten, that is, of 10 to one. Then let us compare the ex∣uperance of the two moveables over air. A is 409 times more dense then air; but B is 499 times more dense then it: by which account the motion of B. must be in that medium swifter then the motion of A, in the proportion of 499 to 409, that is, about 50, to 41: which (to avoid fractions) we may account as 10 to 8. But in water they exceed one another as 10 to one: so that their difference of velocity must be scarce perceptible in air, in respect of what it is in water.

Out of all which discourse, I only infer in common, that a greater velocity in motion will follow the greater density of the moveable; without determining here their proportions, which I leave to them, who make that examination their task: for thus much serves my present turn; wherein I take a survey of nature, but in gross. And my chief drift in this par∣ticular is, only to open the way for the discovering how bodies, that of themselves have no propension to any determinate place, do nevertheless move constantly and perpetually one way; the dense ones descending, and the rare ones ascending: not by any intrinsecal quality that works upon them; but by the oeconomy of nature, that hath set on foot due and plain causes to produce known effects. * 1.93

Here we must crave patience of the great soul of Galileus, (whose admirable learning all posterity must reverence), whiles we reprehend in him that which we cannot term lesse then

absurd: and yet, he not only maintains it in several places, but also professes Dial. P^o. de motu, pag. 81. to make it more clear then day. His position is, that more or less gravity con∣tributes nothing at all to the faster or slower descending of a natural body: but, that all the effect it gives to a body is to make it descend or not descend, in such a Medium. Which is against the first and most known principal that is in bodies; to wit, that more doth more, and less doth less: for he allows, that gravity causes a body to descend; and yet will not allow, that more gravity causes it to descend more.

I wonder he never mark'd how, in a pair of scales, a super∣proportion of the overweight in one ballance, lifted up the o∣ther, faster then a less proportion of overweight would do; Or that more weight hang'd to a jack made the spit turn faster; or, to the lines of a Clock, made it go faster; and the like.

But, his argument, wherby he endeavours to prove his posi∣tion, is yet more wonderful: for, finding in pendants unequal in gravity, that the lighter went in the same time almost as fast as the heavier; he gathers from thence, that the different weights have each of them the same celerity, and that it is the opposition of the air, which makes the lighter body not reach so far at each undulation, as the heavier. For reply whereto, first, we must ask him whether experience or reason taught him, that the slower going of the lighter pendant proceeded only from the Medium, and not from want of gravity? And when he shall have answer'd (as he needs must) that experience doth not shew this; then we must importune him for a good reason▪ but I do not find that he brings any at all.

Again, if he admits, (which he doth in express terms) that a lighter body cannot resist the Medium so much as a heavier body can; we must ask him, whether, it be not the weight that makes the heavier body resist more! which when he has acknowledg'd, that it is; he has therein likewise acknowledg'd that, whenever this happens in the descending of a body, the more weight must make the heavier body descend faster.

But we cannot pass this matter without noting, how himself makes good those arguments of Aristotle, which he seems by no means to esteem of. For, since the gravity overcomes the resistance of the Medium in same some proportion, it follows, that

the proportions between the gravity and the medium may be multiplied without end: so as, if he suppose that the gravity of a body makes it go at a certain rate in Imaginary Space, (which is his manner of putting the force of gravity,) then there may be given such a proportion of a heavy body to the medium, as it shall go in such a medium at the same rate; and nevertheless there will be an infinite difference, betwixt the resistance of the medium compared to that body, and the re∣sistance of the Imaginary Space compared to that other body which he supposed to be moved in it at the same rate: which no man will stick at confession to be very absurd.

Then turning the scales, because the resistance of the medium somewhat hinders gravity, and that with less resistance the heavy body moves faster; it must follow, that, since there is no proportion betwixt the medium and imaginary space, there must neither be any proportion betwixt the time in which a heavy body shall pass through a certain quantity of the medium, and the time in which it shall pass through as much imaginary space: wherefore, it must pass over so much imaginary space: in an instant. Which is the argument that Aristotle is so much laugh'd at for pressing. And in a word, nothing is more evi∣dent, then that, for this effect which Galileo attributes to gravi∣ty, 'tis unreasonable to put a divisible quantity, since the effect is indivisible: And therfore as evident it is that, in his doctrine, such a quality, as intrinsecal gravity is conceiv'd to be, ought not to be put; since every power should be fitted to the effect or end for which it is put.

Another argument of Galileo is as bad as this; when he en∣deavours to prove, that all bodies go of a like velocity, because it happens that a lighter body, in some case, goes faster then a heavier body in another case: as for example, in two pendants, whereof the lighter is in the beginning of its motion, and the heavier towards the end of it; or if the lighter hangs at a lon∣ger string, and the heavier at a shorter; we see that the lighter will go faster then the heavier. But this concludes no more, then if a man should prove a lighter goes faster then a hea∣vier, because a greater force can make it go faster: for 'tis ma∣nifest that, in a violent motion, the force, which moves a body in the end of its course, is weaker then that which moves it in the beginning: and the like is, of the two strings.

But here 'tis not amiss to solve a Probleme he puts, which be∣longs to our present subject. He findes by experience, that, * 1.94 if two bodies descend at the same time from the same point and go to the same point, the one by the inferiour quarter of the circle, the other by the chord to that arch, or by any other lines which are chords to parts of that arch: he findes (I say) that the moveable goes faster by the arch, then by any of the chords. And the reason is evident, if we consider, that the nearer any mo∣tion comes to a perpendicular one downwards, the greater velocity it must have: and that in the arch of such a quadrant, every particular part of it inclines to the perpendicular of the place where it is, more then the part of the chord answerable to it doth.

CHAP. XI. An Answer to Objections against the causes of natural motion, avow'd in the former Chapter; and a refutation of the contrary opinion.

BUt, to return to the thrid of our Doctrine; There may per∣adventure * 1.95 be objected against it, that, if the violence of a bodies descent towards the center did proceed only from the density of it (which gives it an aptitude, the better to cut the medium, and from the mltitude of little atomes descending that strike upon it, and press it the way they go; which is downwards: then it would not import whether the inner part of that body were as solid as the outward parts; for it cuts with only the outward, and is smitten only upon the outward. And yet ex∣perience shews us the contrary: for a great bullet of lead, that is solid and lead throughout, descends faster then if three quarters of the Diameiter were hollow within; and such a one, falling upon any resisting substance, works a greater effect then a hollow one. And a ball of brass that hath but a thin outside of metal, will swim upon the water, when a massie one sinks presently. Whereby it appears, that it is rather some other quality belonging to the very bulk of the metal in it self; and not these outward causes that occasion gravity.

But this difficulty is easily overcome, if you consider, how subtile those atomes are which, descending downwards & strik∣ing

upon a body in their way, cause its motion likewise down∣wards: for, you may remember how we have shew'd them to be the subtilest and the minutest divisions that Light, the subtilest and sharpest divider in nature, can make. It is then easie to conceive, that these extreme subtile bodies penetrate all o∣thers, as light doth glass; and run through them, as sand through a small sieve, or as water through a spunge: so that they strike, not only upon the Superficies, but as well in every most interiour part of the whole body; running quite through it all, by the pores of it. And then, it must needs follow, that the solider it is, and the more parts it has within (as well as with∣out) to be strucken upon; the faster it go, and the greater effect it must work in what falls upon: whereas, if three quar∣ters of the Diameter of it within should be fill'd with nothing but air, the atoms would fly without any considerable effect through all that space; by reason of the rarity & cessibility of it.

And, that these atoms are thus subtile, is manifest by several effects which we see in nature. Divers Authors that write of Egypt assure us, that, though their houses be built of strong stone, nevertheless a clod of earth, laid in the inmost rooms and shut up from all appearing communication with air, will encrease its weight so notably; as therby they can judge the change of weather, which will shortly ensue. Which can pro∣ceed from no other cause, but a multitde of little atoms of Saltpeter; which, floating in the air, penetrate through the strongest wals and all the massie defences in their way: and settle in the cold of earth as soon as they meet with it; because it is of a temper fit to entertain, and conserve, embody them. Delights have shewed us the way, how to make the spi∣rits or atoms of Snow and Saltpeter pass through a glass vessel; which Alchimists hold to be the most impenetrable of all they can find to work with. In our own bodies, the aches which feeble parts feel before change of weather, and the heaviness of our heads and shoulders, if we remain in the open air presently after sunset, abundantly testifie, that even the grosser of these atoms (which are the first that fall) do vehemently penetrate our bodies: so as, sense will make us believe what reason per∣adventure could not.

But, besides all this, there is yet a more convincing reason, why

the descending atomes should move the whole density of a bo∣dy; even though it were so dense that they could not penetrate it, and get into the bowels of it, but must be content to strike barely upon the outside of it. For, nature has so order'd the matter, that, when dense parts stick close together, and make the length composed of them to be very stiff, one cannot be moved but that: all the rest (which are in that line) must likewise be thereby moved: so that, if all the world were composed of atoms closse sticking together, the least motion imaginable must drive on all that were in a straight line, to the very end of the world. This you see is evident in reason; and experience confirms it, when, by a little knock given at the end of a long beam, the sha∣king (which makes sound) reaches sensibly to the other end. The blind man, that governs his steps by feeling in defect of eyes, receives advertisements of remote things through a staff which he holdeth in his hands; peradventure more particularly then his eyes could have directed him. And the like is of a deaf man, that hears the sound of an Instrument; by holding one end of a stick in his mouth, whiles the other end rests upon the Instrument. And some are of opinion (and they not of the rank of vulgar Philosophers) that, if a staff were as long as to reach from the Sun to us, it would have the same effect in a moment of time. Although, for my part, I am hard to believe we could receive an advertisement so far; unless the staff were of such a thickness as, being proportionable to the length, might keep it from facile bending: for, if it should be very plyant, it would do us no service; as we experience in a thrid, which, reaching from our hand to the ground, if it knock against any thing, makes no sensible impression in our hand.

So that, in fine, reason, sense, and authority, all of them shew us, that, the less the atomes should penetrate into a moving body, by reason of the extreme density of it, the more efficaci∣ously they would work, and the greater celerity they would cause in its motion. And, hence we may give the fullest solution to the objection above; Which was to this effect: that, seeing divi∣sion is made only by the superficies or exteriour part of the dense body: and the virtue whereby a dense body works is onely its resistance to division; which makes it apt to divide: it would follow, that a hollow bowl of brass or iron should be as

heavy as a solid one. For, we may answer, that, seeing the atoms must strike through the body; and a cessible body doth not re∣ceive their strokes so firmly as a stiffe one, nor can convey them so far: if to a stiff superficies there succeed a yielding inside, the strokes must of necessity lose much of their force; and conse∣quently, cannot move a body full of air with so much celerity, or with so much efficacy, as they may a solid one.

But then you may peradventure say, that, if these strokes of the descending atomes upon a dense body were the cause of its * 1.96 motion downwards, we must allow the atomes to move faster then the dense body; that so they may still overtake it and drive it along, and enter into it: whereas, if they should move slower then it, none of them could come in their turn to give it a stroke; but it would be past them, and out of their reach before they could strike it. But it is evident (say you), out of these pretended causes of this motion, that such atomes cannot move so swiftly downwards, as a great dense body; since their littleness and their rarity are both of them hindering to their motion. Therefore this cannot be cause of that effect which we call gra∣vity.

To this I reply, That to have the atoms give these blows to a descending dense body, 'tis not requir'd that their natural and ordinary motion should be swifter then the descent of such a dense body; but the very descent of it occasions their striking it; for, as it falls and makes it self a way through them, they di∣vide themselves before it, and swell on the sides and a little a∣bove it; and presently close again behind it and over it, assoon as it is past. Now, that closing, to hinder vacuity of space is a sud∣den one, and thereby attains great velocity; which would car∣ry the atoms in that degree of velocity further than the de∣scending body, if they did not encounter with it in their way to retard them: which encounter and tarding implyes such strokes upon the dense body, as we suppose to cause this motion. And the like we see in water, into which letting a stone fall, presently the water, that was divided by the stone and swells on the sides higher then it was before, closes upon the back of the descen∣ding stone; and follows it so violently, that, for a while after, it leaves a purling hole in the place where the stone went down: till, by the repose of the stone, the water returns likewise to its quiet; and so its superficies becomes even.

In the third place, an enquiry occurs emergent out of this doctrine, of the cause of bodies moving upwards and down∣wards: * 1.97 Which is, Whether there would be any natural mo∣tion deep in the earth, beyond the activity of the Sun beams? for, out of these principles, it follows that there would not: and consequently there must be a vast Orb in which there would be no motion of gravity or levity. For, suppose the Sun beams might pierce a thousand miles deep into the body of the earth; yet there would still remain a mass, whose Diameter would be near 5000 miles, in which there would be no gravitation nor the contrary motion.

For my part, I shall make no difficulty to grant the inference; as far as concerns motion caused by our Sun: for, what in∣convenience would follow out of it? But, I will not offer at de∣termining, whether there may not be enclosed within that great sphere of earth some other fire, (such as the Chymists talk of), an Archeus, a Demogorgon seated in the centre, like the heart in animals, which may raise up vapours and boyl an air out of them, and divide gross bodies into atoms; and accor∣dingly give them motions answerable to ours, but in different lines from ours, according as that fire or Sun is situated: Since the far-searching Authour of the Dialogues de Mundo hath left that speculation undecided, after he had touched upon it in the Twelfth knot of his first Dialogue.

Fourthly, it may be objected, that, if such descending atoms, * 1.98 as we have described, were the cause of a bodies gravity and descending towards the center; the same body would, at divers times, descend more and less swiftly: for example, after mid∣night, when the atoms begin to descend more slowly, the same body would descend more slowly in a like propor∣tion, and not weigh so much as it did in the heat of the day. The same may be said of Summer and Winter; for, in Winter time, the atoms seem to be more gross, and conse∣quently, to strike more strongly upon the bodies they meet with in their way as they descend: yet, on the other side, they seem in the Summer to be more numerous, as also to descend from a greater height; both which circumstances will be cause of a stronger stroke and more vigorous impulse on the body they hit. And the like may be objected of divers

parts of the World; for, in the Torrid Zone it will always hap∣pen as, in Summer, in places of the Temperate Zone, and in the Polar times, as in deepest winter: so that no where there should be any standard or certainty in the weight of bodies, if it depen∣ded upon so mutable a cause. And it makes to the same effect, that a body, which lies under a thick rock, or any other very dense body that cannot be penetrated by any great store of a∣toms, should not be so heavy as it would be in the open and free air, where the atoms in their compleat numbers have their full strokes.

For answer to these and such like instances, we are to note, first, that 'tis not so much the number or violence of the percussion of the striking atoms, as the density of the thing strucken, which gives the measure to the descending of a weighty body; and the chief thing, which the stroak of the atoms gives to a dense body, is a determination of the way which a dense body is to cut to it self: ther∣fore multiplication or lessening of the atoms will not make any sensible difference, betwixt the weight of one dense body where manya toms strike, and an other body of the same density where but a few strike; so that the stroak downwards of the descending atoms, be greater then the stroke upwards of the ascending atoms, and ther∣by determines it to weigh to the Centrewards, and not rise floating upwards; which is all the sensible effect we can per∣ceive.

Next, we may observe, that the first particulars of the ob∣jection do not reach home to enfeeble our doctrine in this particular; although we admit them to be in such sort as they are proposed: for they withal imply such a perpetu∣al variation of causes, ever favourable to our position, that nothing can be infer'd out of them to repugne against it. As thus: When there are many atoms descending in the air, the same general cause which makes them be many makes them also be light, in proportion to their multitude; And so, when they are few they are heavy: likewise, when the atoms are light, the air is rarified and thin; and when they are heavy, the air is thick. And so, upon the whole matter, 'tis evident, that we cannot make such a precise and exact judge∣ment

of the variety of circumstances, as to be able to determine when there is absolutely more cause of weight, and when less. And, as we find not weight enough in either side of these oppo∣site circumstances to turn the scales in our discourse; so likewise we find the same indifference in experience it self: for, the weights we use do weigh equally in mysty weather and in clear; and yet, in rigor of discourse, we cannot doubt but that, in truth, they do not gravitate or weigh so much (though the difference be imperceptible to sense) when the air is thick and foggy, as when its pure and rarified. Which thickness of the Medium, when it arrives to a very notable degree, (as for example to wa∣ter) makes then a great difference of a heavy bodies gravitati∣on in it: and accordingly we see a great difference between heavy bodies descending in water and in air; though between two kinds of air none is to be observ'd, their difference is so smal in respect of the density of the body that descends in them. And therfore, since an assured, and certain difference in circumstances makes no sensible inequality in the affect; we cannot expect any from such circumstances, as we may rea∣sonably doubt whether there be any inequality among them or no.

Besides that, if in any of the proposed cases a heavy body should gravitate more, and be heavier one time than another: yet by weighing it we could not discern it; since the counterpoise (which is to determine its weight) must likewise be in the same proportion heavier then it was. And, besides weighing, no o∣ther means remains to discover its greater graviation, but to compare it to Time in its descent: and I believe that, in all such distances as we can try it in, its inequalities will be no whit less difficult to be observ'd that way, then any other.

Lastly, to bend our discourse particularly to that instance of * 1.99 the objection; where it is conceiv'd that, if gravity or de∣scending downwards of bodies proceeded from atoms striking on them as they move downwards, it would follow, that a stone or other dense body lying under shelter of a thick, hard, and impenetrable adamantine rock, would have no impulse downwards; and consequently would not weigh there. We may note, that no body whatever, compacted by physical causes and agents, can be so dense and imporous, but that

such atoms as these we speak of must be in them, and in every part of them, and every where pass through and through them; as water doth through a sieve or through a spunge: and this universal maxime must extend as far as the Sun, or any other heat communicating with the Sun, reaches and is found.

The reason whereof is, because these atoms are no other thing, but such extreme little bodies as are resolved by heat, out of the main stock of those massie bodies upon which the Sun and heat do work. Now then, it being certain, out of what we have heretofore said, that all mixt bodies have their temper and consistence and generation, from the mingling of fire with the rest of the Elements that compose them; and from the con∣coction or digestion which fire makes in those bodies: 'tis evi∣dent, that no mixt body whatever, nor any sensible part of a mixt body, can be void of pores capable of such atoms, or be without such atoms passing through those pores; which atoms by mediation of the air (that likewise hath its share in such pores) must have communication with the rest of the great sea of air and with the motions that pass in it. And conse∣quently, in all and every sensible part of any such extreme dense and pretended inpenetrable body (to the notice wherof we can arrive), this percussion of atoms must be found; and they will have no difficulty in running through, nor, by means of it, in striking any other body lying under the shelter of it: and thus, both in & from that hard body, there must be stil an uninterrup∣ted continuation of gravity, or of descending towards the centre.

To which we may adde, that the stone or dense body cannot lie so close to the rock that covers it, but that some air must be between, (for if nothing were between, they would be uni∣ted, and become one continued body;) and in that air (which is a Creek of the great Ocean of air spread over the world, that is every where bestrew'd with moving atoms, and which is conti∣nually fed, like a running stream, with new air that drives on the air it overtakes) no doubt but there are descending atoms, as well as in all the rest of its main body: and these descen∣ding atoms, meeting with the stone, must needs give some stroke upon it; and that stroke (be it never so little) cannot chuse but work some effect, in making the stone remove a little that

way they go; and that motion, wherby the space is inlarg'd be∣tween the stone and the shelt'ring rock, must draw in a greater quantity of air and atoms to strike upon it. And thus, by little and little, the stone passes through all the degrees of tardity, by which a descending body parts from rest: which is by so much the more speedily done, by how much the body is more eminent in density. But this difference of time, in regard of the atoms strokes only, and abstracting from the bodies density, will be insensible to us; seeing (as we have said) no more is required of them, but to give a determination downwards.

And, out of this, we clearly see the reason why the same atoms, * 1.100 striking upon one body lying on the water, make it sink; and upon another they do not. As for example, if you lay upon the superficies of some water a piece of iron and a piece of cork, of equal bigness and of the same figure; the iron, will be beaten down to the bottom, and the cork will float at the top. The reason wherof is, the different proportions of the comparison of their densities with the density of water: for (as we have said) the efficacy and force of descending is to be measured by that. So then the strokes of the atoms being more efficatious upon water then upon cork, because the density of water is grea∣ter then the density of cork, considering the abundance of air that is harbor'd in the large pores of it; it followes, that the atoms will make the water go down more forcibly then they will cork: But, the density of iron exceeding the density of water, the same strokes will make the iron descend faster then the water; and consequently, the iron must sink in the water, and the cork will swim upon it.

And this same is the cause, why, if a piece of cork be held by force at the bottom of the water, it will rise up to the top, as soon as the violence is taken away that kept it down: for, the atoms strokes having more force on the water then on the cork, they make the water sink and slide under it; first, a little thin plate of water, and then another, a little thicker, and so by degrees more and more, till it hath lifted the cork quite up to the top. * 1.101

Fifthly, it may be objected, that these atoms do not descend always perpendicularly, but somtimes slopingly; and in that case, if their strokes be the cause of dense bodies moving, they

should move sloping, and not downward. Now, that these atoms descend somtimes slopingly, is evident: as when (for example) they meet with a stream of water, or with a strong wind, or even with any other little motion of the air, such as carries feathers up and down hither and thither; which must needs waft the a∣toms in some measure along with them their way. Seeing then that such a gentle motion of the air is able to put a feather out of its way, notwithstanding the percussions of the atoms upon it; why shall it not likewise put a piece of iron out of its way down∣wards, since the iron hath nothing from the atoms but a deter∣mination to its way? But much more, why should not a strong wind, or a currant of water, do it since the atoms themselv's, that give the iron its determination, must needs be hurried along with them?

To this we answer, that we must consider how any wind or water, which runs in that sort, is it self originally full of such a∣toms, which continually, and every where, press into and cut through it, in pursuing their constant perpetual course of de∣scending; in such sort as we shewed, in their running through any hard rock or other densest body. And these atoms make the wind or water primarily tend downwards; though other acci∣dental causes impel them secundarily to a sloping motion, And still, their primary natural motion will be in truth strongest; though their not having scope to obey that, but having enough to obey the violent motion, makes this become the more ob∣serveable. Which appears evidently out of this, that, if there be a hole in the bottome of the pipe that conveys water sloping∣ly, be the pipe never so long, and consequently the sloping motion never so forcible; yet the water will run out at that hole, to obey its more powerful impulse to the centrewards, rather then continue the violent motion, in which it had arrived to a great degree of celerity.

Which being so; 'tis easie to conceive that the atoms in the wind or water, which move perpendicularly downwards, will still continue the irons motion downwards, notwithstanding the Mediums sloping motion: since the prevailing force determines both the iron and the Medium downward; and the iron has a superproportion of density to cut its way, according as the pre∣valent motion determines it.

But, if the descending atoms be in part carried along down the stream by the current of wind or water, yet still the current brings with it new atoms into the place of those that are carried away; and these atoms, in every point or place wherever they are, of themselvs tend perpendicularly downwards, though they are forced from the compleat effect of their tendance, by the violence of the current: so that, in this case, they are moved by a declining motion, compounded of their own natural motion and the force one with which the stream carries them. Now then, if a dense body fall into such a current where these diffe∣rent motions give their several impulses, it will be carried (in such sort as we say of the atoms, but in another proportion) not in a perpendicular but in a mixt declining line, compound∣ed of the several impulses which the atoms and current give it (in which also 'tis to be remembred, how the current gives an impulse downwards, as well as sloping, and peradventure the strongest downwards): and the declination will be more or less, according as the violent impulse prevails more or less against the natural motion.

But this is not all that is to be consider'd, in estimating the de∣clination of a dense bodies motion, when it is sinking in a cur∣rent of wind or water. You must remember that the dense body it self has a particular virtue of its own (namely its density) by which it receivs and prosecutes more fully its determination downwards; and therfore the force of that body, in cutting its way through the Medium, is also to be considered, in this case as well as above, calculating its declining from the perpendicular: and out of all these causes will result a middle declination; com∣pounded of the motion of the water or wind both ways, and of its own motion by the perpendicular line. And since, of these three causes of a dense bodies motion, its own virtue, in prose∣cuting by its density the determination it requires, is the most efficacious by much, after it has once receiv'd a determina∣tion from without; its declination will be but little, if it be very dense and heavy. But if it recede much from den∣sity, as so have some near proportion to the density of the Medium, the declination will be great. And in a word, according as the body is heavier or lighter, the declina∣tion will be more or less, in the some current: though not

exactly according to the proportion of the diminishing of its density, as long as there is a superproportion of its density to the Medium; since such a superproportion (as we have declared heretofore) makes the Mediums operation upon the dense body scarce considerable.

And hence you see why a stone or piece of iron, is not carri∣ed out of its way, as well as a feather: because the stones motion downwards is greater and stronger then the motion of a feather downwards; And by consequence, the force, that can turn a feather from its course downwards, is not able to deturn a stone. And if it be repli'd, that it may be so order'd that the stone shall have no motion, before it be in the stream of a river; and notwithstanding it will still move downwards: we may answer, that, considering the little declivity of the bed of such a stream, the strongest motion of the parts of the stream must necessiariy be downwards, and consequently, they will beat the stone down∣wards. And, if they do not the like to a feather or other light body, 'tis because other parts of the stream get under the light body, and beat it upwards; which they have not power enough to do to the stone.

Sixthly, it may be objected, that if Elements do not weigh in their own Spheres, then their gravity and descending must pro∣ceed * 1.102 from some other cause, and not from this percussion of the atoms we attribute to it: which percussion we have determin'd goes through all bodies whatever, and beats upon every sensi∣ble part of them. But, that Elements weigh not in their own Spheres appears out of the experience of a Syphon; for, though one leg of a Syphon be sunk never so much deeper into the bo∣dy of the water, then the other leg reaches below the superficies of the water; nevertheless, if once the outward leg become full of water, it will draw it out of the other longer leg. Which it should not do, if the parts of water that are comprised with∣in their whole bulk did weigh: since the bulk of wa∣ter is much greater in the sunk leg then in the other; and therfore these should rather draw back the other water into the Cistern, then be themselves drawn out of it into the air.

To this we answer, that 'tis evident, the Elements, do weigh in their own Spheres; at least, as far as we can reach to their Spheres,

for we see that a ball once stuff'd hard with air is heavier then an empty one. Again, more water would not be heavier then less, if the inward parts of it did not weigh: and, if a hole were dig'd in the bottome of the Sea, the water would not run into and fill it, if it did not gravitate over it. Lastly, there are those who undertake to distinguish, in a deep water, the divers weights which several parts of it have, as they grow still heavier and heavier towards the bottom: and they are so cunning in this art, that they profess to make instruments, which, by their equa∣lity of weight to a determinate part of the water, shall stand just in that part, and neither rise or fall higher or lower; but if it be put lower, it shall ascend to its exact equally weighing Orbe of the water, and if it be put higher, it shall descend till it comes to rest precisely in that place. Whence 'tis evident, that parts of water do weigh within the bulk of their main body; and of the like we have no reason to doubt, in the other two weighty Ele∣ments.

As for the opposition of the Syphon, we refer that point to where we shall have occasion to declare the nature of that en∣gine, on set purpose. And there we shall shew, that it could not succeed in its operation, unless the parts of water did gravitate in their main bulk, into which one leg of the Syphon is sunk.

Lastly, it may be objected, that, if there were such a course of * 1.103 atoms as we say, and their strokes were the cause of so notable an effect as the gravity of heavy bodies; we should feel it pal∣pably in our own bodies which experience shews us we do not.

To this we answer, first, that there is no necessity we should feel this course of atoms: since by their subtilty they penetrate all bodies; and consequently, do not give such strokes as are sen∣sible. Secondly, if we consider that dusts, and straws, and fea∣thers light upon us without causing any sense in us; much more we may conceive that atoms (which are infinitely more subtile and light) cannot cause in us any feeling of them. Third∣ly, we see that what is continual with us, and mingled in all things, doth not make us take any especial notice of it: and this is the cause of the smiting of atoms. Nevertheless, peradventure we feel them in truth, as often as we feel hot and cold weather, and in all Catars or other such changes; which as it were

sink into our body without our perceiving any sensible cause of them: for, no question these atomes are the immediate causes of all good and bad qualities in the air. Lastly, when we consi∣der, that we cannot long together hold out our arm at length, or our foot from the ground; and reflect upon such like impoten∣cies of our resisting the gravity of our own body: we cannot doubt but that, in these cases, we feel the effect of these atomes, working upon those parts; though we cannot, by our sense, discern immediately that these are the causes of it.

But now it is time to draw our Reader out of a difficulty, * 1.104 which may peradventure have perplext him in the greatest part of what he hath hitherto gone over. In our investigation of the Elements we took for a principle thereto, that gravity is sometimes more, sometimes less, then the density of the body in which it is: but in our explication of rarity and density, and again, in our explication of gravity, we seem to put that gravity and density is all one. This thorn, I apprehend, may, in all this distance, have put some to pain: but it was impossible for me to remedy it; because I had not yet deliver'd the manner of gravi∣tation. Here then I will do my best to asswage their grief; by reconciling these appearing repugnancies.

We are therefore to consider, that density (in it self) sig∣nifies a difficulty to have the parts of its subject separated one from another; and that gravity (likewise in it self) signifies a quality, by which a heavy body descends towards the center; or (which is consequent thereto) a force to make an∣other body descend. Now, this power, we have shew'd, be∣long to density: so far forth as a dense body, being strucken by another, doth not yield by suffering its parts to be divided; but, with its whole bulk strikes the next before it and divides it, if it be more divisible then it self is. So that you see Density has the name of Density, in consideration of a passive quality, or rather of an impassibility which it hath: and the same density is call'd Gravity, in respect of an active quality it has, which follows this impassibility. And both of them are estimated by the diffe∣rent respects which the same body or subject, in which they are, has to different bodies that are the terms whereto it is com∣pared: for the active quality, or Gravity, of a dense body, is esteem'd, by its respect to the body it strikes upon; whereas its

Density includes a respect singly to the body that strikes it.

Now 'tis no wonder that this change of comparison works a disparity in the denominations: and that thereby the same body may be conceiv'd to be more or less impartible, then it is active or heavy. A for example, let us of a dense Element take any one least part, which must of necessity be, in its own nature and kind, absolutely impartible; and yet 'tis evident that the gravity of this part must be exceeding little, by reason of the littleness of its quantity: so that thus you see an extremity of the effect of density, joyn'd together in one body (by the acci∣dent of its littleness) with a contrary extremity of the ef∣fect of gravity (or rather with the want of it) each of them with∣in the limits of the same species. In like manner it happens that the same body in one circumstance is more weighty, in an∣other (or rather in the contrary) is more partible: So water in a Pail, because 'tis thereby ••hinder'd from spreading abroad, has the effect of gravity predominating in it, but if it be pour'd out, it has the effect of partibility more. And thus it happens that, meerly by the gradation of rarity and density, one dense body may be apt, out of the general course of natural causes, to be more divisible then to be a divider: though, according to the nature of the degrees consider'd absolutely in themselves, what is more powerful to divide, is also more resi∣stent and harder to be divided. And this arrives in that degree which makes water; for, the falling and beating of the atomes upon water hath the power both to divide and make it de∣scend; but so, that by making it descend it divideth it. And therefore we say it has more gravity then density; though it be the very density of it which is the cause that makes it partible, by the working of one part upon another: for, if the atomes did not find the body so dense as it is they could not, by their beating upon one part make another be divided.

So that, a dense body to be more heavy then dense signifies nothing else, but that it is in such a degree of density, that some of its own parts, by their being assisted and set on work by a ge∣neral cause (which is the fall of the atomes), are powerful e∣nough to divide other adjoyning parts, of the same density with them, one from another: as we see water pour'd out of an Ewer into a Basin, where there is already other wa∣ter, has the power to divide the water in the Basin, by the assi∣stance

of the celerity which it gets in descending. And now I hope the Reader is fully satisfied that there is no contradiction in puting Density and Gravity to be the same thing materially: and that nevertheless the same thing may be more heavy then dense, or more dense then heavy, as we took it, to our several purposes, in the investigation of the Elements.

Having thus laid an intelligible ground to discover how these * 1.105 motions that are general to all bodies and are natural in chief, are contrived by nature; we will now endeavour to shew, that the contrary position is not only voluntary, but also impossible. Let us therfore suppose that a body has a quality to move it downwards. And first we shall ask, what downwards signifies? For, either it signifies towards a fix'd point of Imaginary Space; or towards a fix'd point of the Universe; or, towards some Moveable point. As for the first, who would maintain it must have more imagnation then judgment; to think that a natural quality could have an essence determin'd by a nothing, because we can frame a conceit of that nothing. As for the second, 'tis very uncertain whether any such point be in nature: for, as for the centre of the earthy 'tis clear that, if the earth be carried a∣bout, the centre of it cannot be a fixed point. Again, if the centre signifies a determinate point in the earth that is the Medium of gravity or of quantity, 'tis chang'd as often as any dust lights une∣qually upon any one side of the earth, which would make that side bigger then it was, and, I doubt, a quality cannot have mo∣ral considerations, to think that so little does no harm. As for the third position, likewise 'tis not intelligible how a quality should change its inclination or essence; according to the change that should light now to make one point, now another, be the centre to which it should tend.

Again, let us consider that a quality has a determinate essence. Then, seeing its power is to move, & to move signifies to cut the Medium 'tis moved in; it belongs to it of its nature, to cut so much of such a Medium, in such a time: So that, if no other cause be added, but that you take, precisely & in abstracto, that quality, that Medium, and that time; this effect will follow, that so much motion is made. And, if this effect should not follow, 'tis clear, that The being able to cut so much, of such a Medium, in such a time, is not the essence of this quality, as it was, supposed to be. Dividing then the time and the Medium, half the motion should

be made in half the time, a quarter of the motion in a quarter of the time; and so without end, as far as you can divide. But this is demonstratively impossibly: since 'tis demonstrated, that a moveable coming from rest must of necessity pass through all degrees of tardity; and therefore, by the demonstration ci∣ted out of Galileus, we may take a part in which this gravity cannot move its body, in a proportionate part of time, through a proportionate part of the medium.

But because, in natural Theorems, experiences are naturally * 1.106 required; let us see whether nature gives us any testimony of this verity. To that purpose we may consider a Plummet hang'd in a small string from a beam; which being lifted up gently on the one side at the extent of the string, and permitted to fall meerly by the power of gravity, will ascend very near as high on the contrary side, as the place it was held in from whence it fell. In this experiment we may note two things: First, that, if gravity be a quality, it works against its own na∣ture in lifting up the plummet; seeing its nature is only to carry it down. For, though it may be answer'd, that 'tis not the gravity, but another quality, called vis impressa, which car∣ries it up: nevertheless it cannot be denied, but that gravity is either the immediate, or at least the mediate cause which makes this vis impressa: the effect whereof being contrary to the na∣ture of gravity, 'tis absurd to make gravity the cause of it; that is, the cause of an essence, whose nature is contrary to its own. And the same argument will proceed, though you put not vis impressa, but suppose some other thing to be the cause of the plummets remounting; as long as gravity is said to be a quality: for still gravity must be the cause of an effect contrary to its own inclination, by setting on foot the immediate cause to produce it.

The second thing we are to note in this experiment of the plummets ascent is, that if gravity be a quality, there must be as much resistance to its going up, as there was force to its com∣ing down. Therefore there must be twice as much force to make it ascend, as there was to make it descend; that is to say, there must be twice as much force as the natural force of the gravity is: for there must be once as much to equallize the resi∣stance of the gravity; and then another time as much, to carry

it as far through the same. Medium in the same time. But 'tis impossible that any cause should produce an effect greater then it self.

Again, the gravity must needs be in a determinate degree, and the vertue that makes the plummet remount (whatever it be) may be put as little as we please; and, consequently, not able to oversway the gravity alone, if it be an intrinsecal quality, and yet the plummet will remount: in which case you put an effect withot a cause.

Another experience we may take from the force of sucking: For, take the barrel of a long Gun perfectly bored, and set it upright with the breech upon the ground; and take a bullet that is exactly fit for it, but so as it stick not any where (both the barrel and it being perfectly polished): and then if you suck at the mouth of the barrel, (though never so gently), the bullet will come up so forcibly, that it will hazard the striking out your teeth. Now, let us consider what force were neces∣sary to suck the bullet up, and how very Slowly it would ascend; if in the barrel it had as much resistance to ascend, as in the free air it has inclination to go down. But, if it had a quality of gravity natural to it, it must of necessity have such resi∣stance: wheras, in our experiment, we see it coms as easily as the very air. So that, in this example as wll as in the other, na∣ture teaches us that gravity is no quality.

And all or most of the arguments which we have urg'd a∣gainst the quality of gravity, in that explication we have consi∣der'd it in, have force likewise against it; although it be said to be an Inclination of its subject to move it self to unity with the main stock of its own nature: as divers witty men put it. For, this supposition doth but change the intention or end of gravity, and is but to make it another kind of intellectual or know∣ing Entity, that determines it self to an other end: which is as impossible for a natural quality to do, as to determine it self to the former ends. And thus much the arguments we have proposed do convince evidently, if they be apply'd against this opinion.

CHAP. XII. Of Violent Motion.

ANd thus we have given a shortscantling, wherby to un∣derstand * 1.107 in some measure the causes of that motion we call natural, by reason it has its birth from the universal Oeconomy of nature here among us; that is; from the general working of the Sun, wherby all natural things have their course: and by reason that the cause of it is at all times and in all places constantly the same. Next which the order of discourse leads us to take a survey of those forced motions; whose first causes the more apparent they are, the more obscurity they leave us in, to determine by what means they are continued.

When a Tennis-ball is stroken by a Racket, or an Arrow shot from a Bow, we plainly see the causes of their motion: namely the strings, which, first yielding and then returning with a grea∣ter celerity, cause the missives to speed so fast towards their appointed homes. Experience informs us what qualities the missives must be endued with, to move fast and stedily. They must be so heavy, that the air may not break their course; and yet so light, that they may be within the command of the stroke which gives them motion: the striker must be dense, and in its best velocity: the angle which the missive is to mount by (if we will have it go to its furthest randome) must be the half of a right one: and lastly, the figure of the missive must be such, as may give scope to the air to bear it up, and yet not hinder its course by taking too much hold of it. All this we see: But when with all we see, that the mover deserts the moveable assoon as he has given the blow; we are at a stand, and know not where to seek for that which afterwards makes it flie. For, motion being a transient, not a permanent, thing, assoon as the cause ceases that begot it, in that very point it must be at an end; and as long as the motion continues, there must be some permanent cause to make it do so: so that, as soon as the Racket or bow string go back and leave the ball or arrow, * 1.108 why should not they presently fall straight down to the ground?

Aristotle and hs followers have attributed the cause hereof to the air: but Galileo relishes not this conception. His argu∣ments

against it are (as I remember) to this tenor: Frst, air, by reason of its rarity and divisibility, seems not apt to conserve motion: next, we see that light things are best carried by the air; and it has no power over weighty ones: lastly, it is evi∣dent that air takes most hold of the broadest superficies; and therfore an arrow would fly faster broad waies then long waies, if this were true. Nevertheless, since every effect must have a proportionable cause from whence it immediately flows, and a body must have another body to thrust it on as long as it moves; let us examin what bodies touch a moveable whilst it is in mo∣tion, as the only means to find an issue out of this difficulty; for, to have recourse to a quality or impressed force, for deliverance out of this straight, is a shift that will not serve the turn in this way of discourse we use. In this Philosophy no knot admits such a solution.

If then we enquire, what body 'tis that immediately touches the ball or arrow while it flies; we shall find none others does so but the air and the atoms in it, after the strings have given their stroke and are parted from the missive. And, though we have Galileo's authority and arguments, to discou∣rage us from believing the air can work this effect: yet, since there is no other body, besides it, left for us to consider in this case; let us at the least examin how the air behaves it self, after the stroke is given by the strings. First then tis evi∣dent that, as soon as the rocket or bow-string shrinks back from the missive, and leavs a space between the missive and it (as 'tis clear it does, assoon as it has strucken the resisting body), the air must needs clap in with as much velocity as they re∣tire; and with somwhat more; because the missive goes for∣ward at the same time, and therefore the air must hasten to o∣vertake it, least any vacuity should be left between the string and the arrow. 'Tis certain likewise, that the air on the sides also, upon the division of it, slides back and helps to fill that space which the departed arrow leaves void. Now, this forcible clo∣sing of the air at the nock of the arrow must needs give an im∣pulse or blow upon it: If it seem to be but a little one, you may consider 'tis yet much greater, then what the air and the bo∣dies swiming in it at the first give to a stone falling from high; and how at the last those little atoms, that drive a

stone in its natural motion, with their little blows force it per∣adventure more violently and swiftly, than any impelling agent we are acquainted with can do. So that, the impulse which they make on the arrow, pressing violently upon it after such a ve∣hement concussion and with a great velocity, must needs cause a powerful effect, in that which of it self is indifferent to any mo∣tion any way.

But, unless this motion of the air continue to beat still up∣on * 1.109 the arrow, it will soon fall to the ground, for want of a cause to drive it forward; and because the natural motion of the air (being then the only one) will determine it downwards. Let us consider then, how this violent rending of the air, by the blow the bow-string gives to the Arrow, must needs dis∣order the little atones that swim to and fro in it, and that (be∣ing heavier then the air) are continually descending downwards. This disorder makes some of the heavier parts of them get a∣bove others, that are lighter then they; which they not abiding presse upon those that are next them, and they upon their fellows: so that there is great commotion and undulation cau∣sed in the whole masse of air round about the arrow: which must continue some time before it can be settled; and it being determin'd by the motion of the arrow that way that it slides, it follows, that all this commotion and undulation of the air serves to continue the arrow in its flight. And thus, faster then any part behind can be setled, new ones before are stir'd; till the resistance of the medium grows stronger then the impulse of the movers.

Besides this, the arrow pressing on the air before it, with a greater velocity then the air (which is a liquid rare body) can admit, to move all of a piece without breaking: it must of neces∣sity happen, that the parts of the air immediately before the ar∣row be driven upon others further off, before these can be mo∣ved to give place unto them; so that in some places the air be∣comes condens'd, and consequently in others rarified. Which also the wind we make in walking (which will shake a paper, pin'd loosly at the wall of a chamber towards which we walk), and the cooling air caus'd by faning when we are hot do evidently confirm. So that it cannot be doubted, but condensation and rarefaction of the air must necessarily follow

the motion of any solid body: which being admitted 'tis evident that a greater disorder, and for some remarkable time, must ne∣cessarily be in the air; since it cannot brook to continue in more rarity or density then is natural to it. Nor can weighty and light parts agree to rest in an equal height or lowness; which the violence of the arrows motion forces them to for the pre∣sent. Therefore it cannot be deni'd, but that, though the arrow slide away, there still remains behind it (by this conden∣sation and confusion of parts in the air) motion enough to give impulse to the arrow; so as to make it continue its motion af∣ter the bowstring has left it.

But here will arise a difficulty: which is, how this clapping in * 1.110 and undulation of the air should have strength and efficacy e∣nough to cause the continuance of so smart a motion, as is an ar∣row shot from a bow. To this, I need no other argument for an answer, then to produce Galileo's testimony, how great a body one single mans breath alone can, in due circumstances, give a rapid motion to: and withal, let us consider, how the arrow and the air about it are already in a certain degree of velocity; that is to say, the obstacle that would hinder it from moving that way (namely, the resistance of the air) is taken away, and the causes that are to produce it (namely the determining of the airs and atomes motion that way) are heightned. And then we may safely conclude that the arrow, which of it self is in∣different to be moved upwards or downwards or forwards, must needs obey that motion, which is caused in it by the atomes and the air's pressing upon it: either according to the impulse of the string, or (when the string begins to flag) according to the beating that follows the general constitution of nature, or in a mixt manner, according to the proportions that these two hold to one another. Which proportions Galileus (in his 4 Dialogue of Motion) has attempted to explicate very ingeniously: but, ha∣ving miss'd in one of his suppositions, to wit, that forced moti∣on upon an Horizontal line is throughout uniform, his great labours therein have taken little effect, towards the advancing the knowledge of nature, as he pretended; for, his conclusions succeed not in experience (as Mersenius assures us, after very ex∣act trials), nor can they in their reasons be fitted to nature.

So that, to conclude this point, I find no difficulty in allowing

this motion of the air strength enough to force the moveable onwards, for sometime after the first mover is sever'd from it; (and long after we see no motions of this nature endure:) so that we need seek no further cause for the continuance of it; but may rest satisfied upon the whole matter, that, since the cau∣ses and circumstances our reason suggests to us are, after ma∣ture and particular examination, proportionable to the effects we see, the doctrine we deliver must be sound and true.

For the establishing wherof, we need not (considering what we have already said) spend much time in solving Galileo's ar∣guments * 1.111 against it; seeing, out of what we have set down, the answers to them appear plain enough. For, first, we have assign'd causes how the air may continue its motion, long enough to give as much impression as is needful to the arrow, to make it go on as it does. Which motion is not requisite to be near so great in the air behind the arrow (that drives it on) as what the arrow causes in the air before it: for; by reason of its density, it must needs make a greater impression in the air it cuts, then the air causes its motion, would do of it self without the mediation of the arrow. As, when the force of a hand gives motion to a knife to cut a loaf of bread, the knife, by reason of the density and figure it has, makes a greater impression in the loaf then the hand alone would do. And this is the same that we declared in the natu∣ral motion of a heavy thing downwards; to which we assign∣ed two causes; namely, the beating of the atoms in the air, fal∣ling down in their natural course to determine it the way it is to go; and the density of the body, that, cutting more power∣fully then those atoms can do, gives (together with their help) a greater velocity to the moveable, then the atoms of themselves can give.

Nor imports it that our resolution it aginst the general nature of rare and dense bodies, in regard of conserving motion; as Galileo objects. For, the reason why dense bodies conserve motion longer then rare bodies is because, in regard of their dividing virtue, they get, in equal time, a greater velo∣city: Wherfore, seeing velocity is equal to gravity, it fol∣lows, that resistance works not so much upon them as upon rare bodies; and therfore cannot make them cease from mo∣tion

so easily, as it does rare bodies. This is the general reason for the conservation of motion in dense bodies. But because, in our case, there is a continual cause which conserves motion in the air, the air may continue its motion longer, than of it self it would do: not in the same part of air, which Galileus (as it seems) aim'd at; but in divers parts, in which the moveable successively is.

Which being concluded, let us see how the forced motion comes to decrease and be ended. To which purpose we may observe, that the impression which the arrow receives from the air that drives it forwards, being weaker than that which it re∣ceiv'd at first from the string, (by reason that the air is not so dense, and therfore cannot strike so great a blow); the arrow does not, in this second measure of time, (wherein we consider the impulse given by the air only) cut so strongly the air before it, nor press so violently upon it, as in the first measure when the string parting from it did beat it forwards: for, till then, the velocity encreases in the arrow, as it does in the string that carries it along, which proceeds from rest at the fingers loose from it, to its highest degree of velocity; which is, when it ar∣rives to the utmost extent of its jerk, where it quits the arrow. And therfore the air now doth not so swiftly, nor so much of it, rebound back from before, and clap it self behind the arrow, to fill the space that else would be left void by the arrows moving forward; and consequently, the blow it gives in the third mea∣sure to drive the arrow on, cannot be so great as the blow was immediately after the strings parting from it, which was in the second measure of time: and therefore the arrow must needs move slower in the third measure, than it did in the second; as formerly it moved slower in the second (which was the airs first stroke) than it did in the first, when the string drove it forwards. And thus successively in every moment of time, as the causes grow weaker & weaker, by the encrease of resistance in the air before, and by the decrease of force in the subsequent air; so the motion must be slower and slower, till it come to pure cessation. * 1.112

As for Galileu's second argument, that the air has little power over heavy things; and therfore he will not allow it to be the cause of continuing forced motions in dense bodies: I wish he could as well have made experience, what velocity of motion

a mans breath might produce in an heavy bullet lying upon an even, hard, and slippery plain, (for a table would be too short) as he did, how admirable great a one it produced in pendants hanging in the air; and, I doubt not but he would have granted it as powerful in causing horizontal motions, as he found it in the undulations of his pendants. Which nevertheless suffici∣ently convince how great a power, air has over heay bodies. As likewise the experience of wind-guns assures us, that air duly applyed is able to give greater motion to heavy bodies, than to light ones: For, how can a straw or feather be imagin'd pos∣sibly to fly with half the violence, as a bullet of lead doth out of one of those Engines? And, when a man sucks a bullet upwards in a perfectly bored barrel of a Gun, which the bullet fits ex∣actly (as we have mention'd before); with what a violence doth it follow the breath, and ascend to the mouth of the barrel? I remember to have seen a man, that was uncautious and sucked strongly, that had his foreteeth beaten out by the blow of the bullet ascending.

This experiment (if well look'd into) may peradventure make good a great part of this Doctrine, we now deliver. For, the air, pressing in behind the bullet at the touch-hole, gives it its im∣pulse upwards; to which the density of the bullet being added, you have the cause of its swiftness and violence, (for a bullet of wood or cork would not ascend so fast and so strongly); and the sucking away of the air before it, takes away that resistance, which otherwise it would encounter with, by the air lying in its way: and its following the breath with so great ease shews (as we touch'd before) that of it self, 'tis indifferent to any motion, when nothing presses upon it, to determine it a certain way.

Now to Galileo's last argument, that an arrow should fly fa∣ster * 1.113 broad-ways than long-ways, if the air were cause of its mo∣tion; there needs no more to be said, but that the resistance of the air before hinders it, as much as the impulse of the air be∣hind helps it on: So that nothing is gain'd in that regard, but much is lost in respect of the figure, which makes the arrow un∣apt to cut the air so well when it flyes broad-ways, as when 'tis shot long-ways; and therfore, the air being weakly cut, so much of it cannot clap in behind the arrow and drive it on, a∣gainst the resistance before, which is much greater.

Thus far with due respect, and with acknowledging remem∣brance

of the many admirable mysteries of nature which that great man hath taught the world, we have taken liberty to di∣pute against him: because this difficulty seems to have driven him, against his Genius, to believe that in such motions there must be allow'd a quality imprinted into the moved body, to cause them; which our whole scope, both in this and all other oc∣casions where like qualities are urged, is to prove superfluous and ill grounded in nature, and to be but meer terms to con∣found and leave in the dark, whoever is forced to fly to them.

CHAP. XIII. Of three sorts of violent motion, Reflection, Undulation, and Refraction.

THe motion we have last spoken of, because 'tis ordinarily * 1.114 either in part or wholy, contrary to gravity, (which is ac∣counted the natural motion of most bodies), uses to be call'd vi∣olent or forced. And thus, you have deliver'd you the natures and causes both of Natural and of Forced Motion; yet it remains that we advertise you of some particular kinds of this forced motion; which seem to be different from it, but indeed are not. As first, the motion of Reflection: which, if we but consider how forced motion is made, we shall find it is nothing else but a for∣ced motion, whose line whereon 'tis made is, as it were, snapp'd in two by the encounter of a hard body. For even, as we see in a spout of water strongly shot against a wall, the water follow∣ing drives the precedent parts first to the wall; and after∣wards, coming themselves to the wall, forces them again an∣other way from the wall: so, the latter parts of the torrent of air, which is caused by the force that occasion'd the forced mo∣tion, drives the former parts first upon the resistant body, and afterwards again from it. But, this is more eminent in light than in any other body; because light doth less rissent gravity; and so observes the pure course of the stroke, better than any o∣ther body; from which others, for the most part, decline some way by reason of their weight.

Now, the particular law of reflection is, that the line incident, & the line of reflection must make equal angles, with that line of * 1.115 the resistent superficies wch is in the same superficies with themselvs The demonstration wherof that great wit, Renatus des Cartes,

hath excellently set down, in his book of Dioptricks, by the ex∣ample of a ball strucken by a Racket against the earth, or any re∣sisting body: the substance wherof is, as follows.

In the Rectangle Paral∣lelogramme AE, let CE

[illustration]

be the supersicies of the earth; A, the point from which the Racket HG strikes the Ball, by the line AB, to the point B in the superficies of the Earth: and let us consider C to be on the left hand, and E on the right. Now we are to shew that the ball will rebound by the line BF, to the point F, in the same time in which it went from A to B; and so make the angle ABC equal to the angle FBE For the effecting wherof, we must abstract, ac∣cording to the manner of Mathematicians; from all Physical in∣equalities; and suppose the superficies CE to be Mathematically plain, and the force of the racket to continue equally strong in B as it is in A: for though in truth neither of these be rigo∣rously so; nevertheless, because there is no sensible defect in any operation that depends on them, 'tis the same to our pur∣pose as if they were Mathematically so. We see then that the Racket HG, in a certain time, drives the Ball from A to B: that is to say, from the left hand to the right, as far as from C to B; and from above to downwards as far as from A to C. We see again, that the superficies CE is not contrary to this motion of the Ball as it goes from the left hand to the right; for the line CE lies likewise that way: but is contrary to it, as it goes from above down∣ward; for in that course

[illustration]

the superficies CE encoun∣ters and puts a period to the line AC. And therfore the motion of the ball, when it meets with the superficies CE, must be changed from the line AC, so much as the superficies CE is contrary to it; that is, quite backwards as far as it depends on that op∣position. Therfore, when the Ball is come to B, it must go from thence in the same proportion of left to right hand, and from below upwards; as it came before, from left to right

hand, and from above downwards, when it came from A to B. And consequently, it must, in equal time, have passed another line from left to right hand, as long as the line CB; and at the same time, another from below upwards as long as AC: which will of necessity make it hit in the point F, at the end of so much more time as it spent in going from A to B; and so make the two Angles ABC and FBE equal, as every one knows that has but saluted Euclide.

The motion which we call Undulation needs no further ex∣plication: * 1.116 for 'tis manifest, that, since a Pendent, when 'tis re∣moved from its perpendicular, will restore it self therto by the natural force of gravity, and that in so doing it gains a veloci∣ty, (and therefore cannot cease on a suddain); it must needs be carried, out of the force of that motion, directly the con∣trary way: till, the force of gravity overcoming the velocity, it must be brought back again to the perpendicular; which being done likewise with velocity, it must send it again towards the place from which it fell at the first. And in this course of motion it must continue for a while, every Undulation being weaker then other; till at last it quite ceases, by the course of nature setling the air in its due situation, according to the natu∣ral causes that work upon it. And in this very manner also is performed that Undulation we see in water, when it is stir'd from the natural situation of its Spherical superficies.

Galileo hath noted, that the time in which the Undulations are made which follow one another of their own accord, is the same in every one of them; and that, as much time precisely is taken up in a pendants going a very short arch towards the end of its vibration, as was in its going the greatest arch at the be∣ginning of its motion. The reason wherof seems strange to him, and he thinks it an accident natural to the body out of its gravity; and that this effect convinces, it is not the air which moves such bodies. Wheras, in truth, 'tis clearly the air which causes this effect: Because the air, striving at each end (where it is furthest from the force of the motion) to quiet it self, gets at every bout somwhat upon the space; and so contracts that into a shorter arch.

But, 'tis a great wonder to me, that Galileo should make a

wonder of this effect, to the reason of which he hath laid so fair a foundation upon another occasion, had he but reflected on it. For (in his fourth Dialogue, of Motion) he hath demon∣strated, that a natural movable descending in the quarter of a circle, from what part soever it begins, spends equal time to come to the lowest point, as if it came from any other part: so that a Pendant, being brought up to any height by the force of a formermotion downwards, will be sure to spend as much time in going down from thence to the Perpendicular, as it did at the first when it was let fall from the greatest height. Now I subsume, that the pendants ascending being the effect of the velocity of its motion gain'd in descending immediatey before; the said velocity must be able to carry it, in the same time, to a height proportionate to that, to which the velocity, gain'd in the first fall, did cause the pendant to mount. As for example. If the pendants first descent

[illustration]

were from A to E, the second from C to E; because the time of those two is the same, (as Galileus hath demonstrated), it follows that their veloci∣ties gain'd in deseending must of necessity be in the proportion of the line AE to the line CE: therefore, their effects also must be proportionable. Let us then put the line ED in that propor∣tion to the line CE, which CE hath to AE; and then the velo∣city gain'd in CE will carry the pendent up from E to D, in the same time in which the descent AE did carry it up the other way from E to C: wherfore, seeing that the times of its descent from A to E, and from C to E, are equal; likewise the two vibra∣tions from A to C, and from C to D will be done in equal times. But, that which made Galileo not see the force of the conse∣quence was, that he did not acknowledge violent motion to be made in the same proportions, and for the same reasons, which are found in natural motion, and for the same reasons, which are found in natural motion: which we have above shew'd to be so, where we discoursed of the matter.

That motion also which we call Refraction, and is manifest * 1.117 to sense only in light, (though, peradventure hereafter, more diligent searchers of nature may likewise find in such other bodies as are called qualitie; as in cold or heat, &c.) is but a

kind of Reflexion. For, there being certain bodies▪ in which the passages are so well order'd with their resistences, that all the parts of them seem to permit light passe through them, and yet all seem to reflect it; when light passes through such bo∣dies, it finds at the very entrance of them such resistences where it passes, as serve it for a reflecting body; and yet such a refle∣ctent body, as hinders not the passage through, but only from being a staight line with the line incident. Wherfore the light must needs take a ply, as beaten from those parts, towards a line drawn from the illuminant falling perpendicularly upon the resisting superficies; and therfore is term'd by Mathemati∣cians, to be refracted or broken towards the perpendicular. Now, at the very going out again of the light, the second su∣perficies (if it be parallel to the former) must needs, upon a con∣trary cause, strike it the contrary way: which is which is ter∣med from the perpendicular.

As for example, If the ray AB, lights

[illustration]

upon the superficies EBF, and findes en∣trance: 'tis not now the superficies EF that resists or re∣flects it: but 'tis that part of the inside (as we may say of the Pore B towards F; being a Physical body, not a Mathematical Point. The reflection therfore must be made, as if the reflectent body were IBK: but 'tis evident that if AB did strike upon IK, it would reflect towards AG. But, because we know not the in∣clination of the superficies IK, whether it be truly a perpendi∣cular or no; therfore we cannot tell the quantity of the incli∣nation which this reflection must make; but only we know it must be towards AG. * 1.118

But, before we wade any deeper into this difficulty, we cannot omit a word of the manner of explicating Refraction, which Monsieur des Cartes uses; so witty a one as I am sorry it wants success. He therefore, following the demonstration above

given of Reflection; supposes the superficies which a ball lights upon, to be a thin linen cloth; or some other such matter as will break cleanly, by the force of the ball striking smartly upon it. And because that superficies resists only one way, therfore he in∣fers that the velocity of the ball is lessen'd only one way and not the other: so that the velocity of its motion, that way in which it finds no resistance, must be (after the balls passage through the linnen) in a greater proportion to the velocity which it has the other way were it finds resistance, then it was before. And therfore the ball will in less time arrive to its pe∣riod on the one side then on the other: and consequently, lean towards that side to which the course wherin it findes no op∣position carries it.

But, how much he is mistaken upon the whole matter a little figure will shew. Let us therefore put a Rectangle Parallelogram (as be∣fore) AE,

[illustration]

which I double & make the whole Pa∣rallelogrā AL, and draw out the line AB, till it comes to L. Now, we must imagin, that CE is the cloth or passible superficies, which Monsieur des Cartes puts; and BL the line it would go in, if there were no resistance. Next, we must seek the perpendicular; which, according to our explication, is AC: for that falls from A the illuminant perpendicularly upon CE; although, some who defend Monsieur des Cartes seem to make another line the perpendicular, against the conception of all those that write of Opticks. But not to trouble our selvs with terms, the question is, whether the ball that passes the cloth must (after its passage through) deflect from the line BL. (which it would have kept, had there been no resistance) towards E; or else deflect from that line towards C. And, both experience and reason assure us, that it must turn towards C: but Monsieur des Caries saith towards E.

Which to shew how it is contrary to his own principle; Let

us conceive the cloth CE to be of some thickness, and so draw the line OP to determine that thickness. And let us make from B upon AL another Parallelogram, like the Parallelogram AL, whose Diameter shall be BQ. And it must necessarily fol∣low, that the motion from B to Q, if there were no resistance, were in the same proportion as from A to B. But the proporti∣on of the motion as from A to B is the proportion of CB to CA that is, it goes in the same time, faster towards D, then towards M, in proportion which CB hath to CA. By which account, the resistance it has in the way towards D must also be greater, then the resistance it has in the towards M, in the proportion which CB has to CA; and therfore the more tardicy must be in the way to D, and not in the way to M: and consequently, the declination must be from E wards, and to M wards. For, where there is most resistance, that way likewise must the tardity be greatest, and the declination must be from that way: but, which way the thickness, to be passed in the same time, is most, that way the resistance is greatest; and the thickness is clearly grea∣ter towards E, then towards M; therfore, the resistance must be greatest towards E, and consequently, the declination from the line BL must be towards M, and not towards E.

But, the truth is, in his Doctrine, the ball would go in a straight line, as if there were no resistance; unless peradven∣ture towards the contrary side of the cloth, at which it goes out into the free air. For, as the resistance of the cloth is greater in the way towards D, then in the way towards M, (because it pas∣ses a longer line in the same time, as also it did formerly in the air); so likewise is the force that moves it that way greater, then the force which moves it the other. And therfore, the same proportions that were in the motion, before it came to the re∣sisting passage, will remain also in it, at least till, coming near the side at which it goes out, the resistance be weakned by the thinness of the resistent there: which, because it must needs happen on the side that has least thickness, the ball must con∣sequently turn the other way, where it findes greatest yielding; and so at its getting out into the free air, it will bend from the greater resistance, in such manner as we have said above.

Neither do the examples, brought by Monsieur des Cartes * 1.119 and others in the maintenance of this Doctrine, any thing avail

them: for when a Canon Bullet shot into a River hurts the people on the other side; 'tis not caused by refraction, but by * 1.120 reflection, as Monsir des Cartes himself acknowledges; and therfor, has no force to prove any thing in refraction, whose Laws are divers from those of pure reflection.

And the same answer servs against the instance of a Musket bullot shot at a mark under water; which perpetually lights higher then the mark, though exactly just aim'd at. For, we knowing that it is the nature of water, by sinking in one place to rise round about; it must of necessity follow that the bullet, which in entring has press'd down the first parts of the water, has withal therby put others further off in a motion of rising: and therfore the bullet, in its going on, must meet with some water swelling upwards; and from it receive a ply that way, which cannot fail of carrying it above the mark it was level'd at. And so we see this effect proceeds from reflection, or the bounding of the water, and not from refraction. Besides that, it may justly be suspected the shooter took his aim too high, by reason of the marks appearing in the water higher than in truth it is: unless such false aiming were duly prevented.

Neither is Monsir des Cartes his excuse to be admitted, when he saies that light goes otherwise than a ball would do; be∣cause in a glass or water, the etherial substance, which he surposes to run through all bodies, is more efficaciously moved than in air: and thersore light must go faster in the glass than in the air, and so turn on that side of the straight line which is contrary to the side that the ball takes, because the ball goes not so swiftly. For, (not to dispute the verity of this propo∣sition) the effect he pretends is impossible: for, if the etherial suhstance in the air, before the glass, be flowly moved, (the mo∣tion of which he calls light); 'tis impossible that the etherial substance in the glass or in the water should be more smartly moved than it. Well it may be less; but without all doubt the impulse of the etherial substance in the Glass cannot be grea∣ter than its adequate cause; which is the motion of the other parts that are in the air precedent to glass.

Again, after it is pass'd the glass, it should return to be a straight line with the line that it made in the air precedent to the glass; in the subsequent air must take off just as much (and no more) as the glas did add: the contrary wherof experience shews us.

Thirdly, in this explication it would always go one way in the air, and another way in the glass: wheras all experience testi∣fies that, in a glass convex on both sides, it still goes in the air, after its going out, to the same side as it did in the glass; but more. And the like happens in glasses on both sides concave, Wherfore 'tis evident, that 'tis the snperficies of the Glass that is the worker on both sides: and not the substance of the air on one side, and of the glass on the other.

And lastly, his answer no way solvs our objection; which proves that the resistance both ways is proportionate to the force that moves; and, by consequence, that the thing moved must go straight. As we may imagine would happen, if a bullet were shot stoping through a green mud wall, in which there were many round sticks, so thin set that the bullet might pass with ease through them; for, as long as the bullet touched none of them (which express his case) it would go straight; but, if it touch'd any (which resembles ours, as by and by will apperar), it would glance according to the quality of the touch, and move from the stick in another line.

Some peradventure may answer for Monsieur des Cartes, that * 1.121 this subtile body, which he supposes to run through all things, is stiff and no ways pliable. But, that is so repugnant to the na∣ture of rarity, and so many insuperable inconveniences follow out of it, as I cannot imagin he will own it; and therfore I will not spend any time in replying therto.

We must therfore seek some other cause of the refraction of light, which is made at the entrance of it into a Diaphanous bo∣dy. Which is plainly (as we said before), because the ray, stri∣king against the inside of a body it cannot penetrate, turns by reflection towards that side on, which the illuminant stands and if it findes clear passage through the whole resistent, it follows the course it first takes; if not, then 'tis lost by many reflecti∣ons to and fro.

And that this Doctrine is true, the accidents or Phoenomenas evidently declare to us: for experience teaches that, upon a plain superficies, the refraction is made towards the perpendi∣cular drawn from the illuminant to the superficies; as we have said. Now, at the going out (if the surfaces be parallels) we see that the ray turns from that perpendicular; which also is ne∣cessary; for, going through a pore bigger than it self, or at the

least as big, and finding it full of air, it must needs be crowded there now, in a crowd, he presses you most whom you press most upon: so then that side of the pore, which is next the light as it passes, must press most upon it. But,

[illustration]

the angle which is towards the perpendicular, to wit, the Angle BCI, is the lesser, and by conse∣quence, the ray is nearer that side of the pore which is toward I, then the other side of it which is towards H, wher∣fore it must take its ply from that side: But, that side strikes it frō the perpendicular: therfore it must there retract from the per∣pendicular.

This very same doctrine, for the reason of refraction, is con∣firm'd by what happens in crooked superficies. As if EF be a Lens, or glass, on both sides convex; and CB the

[illustration]

axis of it; AD the ray falling from the illu∣minant A; AB the per∣pendicular falling from the same illuminant A: it will be plain, by the for∣mer discourse, that the ray AD must, at the en∣try, be refracted towards AB, as being repulsed from that part of the in∣side of the pore D, which is towards F; because that side is most opposed to the ray. Now, the ray be∣ing once turn'd that way, when, at the end of is journey through the

glass, 'tis come to the other superficies EGF, it makes the lesser angle towards F: and therfore must it, by the rule given above, be refracted again, at its parting from the glass, towards the same perpendicular; and it will meet somewhere with the axis CB; all which experience shews us to be true.

And, taking a body of

[illustration]

concave surfaces, we shall (according to this doctrine of ours) find the causes of refraction just contrary; and ac∣cordingly, experience likewise shews us the effects to be so too. Therfore since experi∣ence agrees exactly with our rules, we can∣not doubt but the prin∣ciples upon which we go, are well laid.

But, because crooked * 1.122 surfaces may have ma∣ny irregulalities; it will not be amiss to give a rule, by which all of them may be brought to a certainty. And this it is, that Re∣flections from crooked superficieses are equal to the reflections that are made from such plain superficieses, as are tangents to the crooked ones in that point from whence the reflections are made. Which Principle the Masters of Opticks take out of a Mathematecal supposition, of the Unity of the reflecting point in both the surfaces, the crooked and the plain. But, we take it out of the insensibility of the difference of so little a part in the two different surfaces, as serves to reflect a ray of light: For, where the difference is insensible in the causes, there likewise the difference is so little in the effects, as sense cannot judge of them; which is as much as is requisite to our purpose. Now since, in the Mathematical supposition, the point where the re∣flection is made is indifferent to both the surfaces: it follows,

that it imports not whether superficies you take to know the quality of reflection by. This principle then being setled, that the reflection must follow the nature of the tangent sur∣faces; and it being proved, that, in plain surfaces, it will hap∣pen as we have explicated; it follows, that, in any crook∣ed supersicies, of what Figure soever, the same also will happen.

Now, seeing we have formerly declared, that refractions are but a certain kind of reflexions; what we have said here of re∣flections may be apply'd to refractions.

But, there remains yet untouch'd one affection more of refra∣ctions; which is, that some Diaphanous bodies in their inward * 1.123 parts reflect more, than others (which is that we call refraction) as experience shews us. Concerning which effect, we are to consider, that Diaphanous bodies may, in their composition, have two differences: for, some are composed of greater parts and greater pores; others, of lesser parts and lesser pores. 'Tis true, there may be other combinations of pores and parts; yet by these two the rest may be esteem'd. As for the first combination, we see that, because the pores are greater, a greater multitude of parts of light may pass together through one pore; and, because the parts are greater, likewise a greater multitude of rays may reflect from the same part, and find the same passage quite throughout the Diaphanous body. On the contrary side, in the second combination; where both the pores and the parts of the Diaphanous body are little, the light must be but little that finds the same passage.

Now, that refraction is greater or lesser, happens two ways: for, 'tis either when one Diaphanous body reflects light at more angles, than another, and by consequence in a greater extent of the superficies; or else when one body reflects light from the same point of incidence, in a shorter line and a greater angle, than another does. In both these wayes 'tis apparent that a body, composed of greater parts and greater pores, exceeds bo∣dies of the opposite kind: for, by reason that, in the first kind, more light may beat against one part, a body in which that happens will wake an appearance from a further part of its superficies: wheras, in a body of the other sort, the light that beats against one of the little parts of it will be so little, as

'twill presently vanish. Again, because in the first, the part at the incidence is greater, the surface from which the reflection is made inwards, has more of a plain and straight superficies: and consequently reflects at a greater angle, than that whose superfi∣cies hath more of inclining.

But, we must not pass from this question, without looking a little into the nature of those bodies in which refraction is * 1.124 made: for, if they, as well as the immediate causes of refraction, likewise favour us; it will not a little advance the certainty of our determination. To this purpose we may call to mind, how expe∣rience shews us that great refractions are made in smoke and mists, and glasses, and thick-bodied waters; and Monsir des Cartes adds certain Oyls and Spirits or strong Waters.

Now, most of these, we see, are composed of little consistent bodies, swimming in another liquid body. As is plain in smoke and mists: for the little bubbles which rise in the water before they get out of it, and that are smoke, when they get into the air, assure us, that smoke is nothing else, but a company of little round bodies swimming in the air; and the round consistence of water upon herbs, leavs, & twigs, in a rind or dew, gives us also to understand, that a Mist is likewise a company of little round bodies, that sometimes stand, sometimes float in the air, as the wind drives them. Our very eyes bear witness to us, that the thicker sort of waters are full of little bodies; which is the cause of their not being clear.

As for Glass, the blowing of it convinces, that the little darts of fire, which pierce it every way, do naturally, in the mel∣ting of it, convert it into little round hollow bodies; which, in their cooling, must settle into parts of the like figure. Then, for Chrystal and other transparent stones which are found in cold places; it cannot be otherwise, but that, the nature of cold pier∣cing into the main body, and contracting every little part in it self, this contraction must needs leave vacant pores between part and part. And, that such transparent stones as are made by heat have the like effect and property, may be judg'd out of what we see in Bricks and Tiles; which are left full of holes by the operation of the fire. And I have seen, in bones that have lain a long time in the Sun, a multitude of sensible little pores close to one another; as if they had been formerly stack all over

with subtile sharp needles, as close as they could be thrust in, by one another. The Chymical Oyles and Spirits, which Monsir des Cartes speaks of, are likely to be of the same composition; since such use to be extracted by violent fires: for a violent fire is made by the conjunction of many rayes together; and that must needs cause great pores in the body it works on; and the stick∣ing nature of these spirits is capable of conserving them.

Out of all these observations it follows, that the bodies, in which greatest refractions happen are compounded (as we have said) of great parts, and great pores: and therfore, by only taking light to be such a body, as we have described it, where we treated of its nature, 'tis evident, the effect we have exprest must necessarily follow by way of reflection; and refraction is nothing else but a certain kind of reflection.

Which last assertion is likewise convinced out of this, that the same effects proceed from reflection, as from refraction; for, by reflection a thing may be seen greater, than it is, in a different place from the true one where it is; colours may be made by re∣flection, as also gloating light, and fire likewise; and peradven∣ture all other effects which are caused by refraction, may as well as these, be perform'd by reflection. And therfore 'tis evident, they must be of the same nature; since children are the resem∣blances of their parents.

CHAP. XIV. Of the composition, qualities, and generation of mixed bodies.

HAving now declar'd the vertues by which Fire and Earth work upon one another, and upon the rest of the Elements; * 1.125 which is, by Light, and the motions we have discours'd of: Our task shall be in this Chapter, first, to observe what will result out of such action of theirs; and next, to search into the ways and manner of compassing and performing it. Which latter we shall the more easily attain to, when we first know the end that their operation levels at. In this pursuit we shall find, that the effect of the Elements combinations, by means of the motions that happen among them, is a long pedegree of compounded qua∣lities and bodies wherein the first combinations (like mar∣riages) are the breeders of the next more-composed sub∣stances, and they again are the parents of others in greater

variety; and so are multiplied without end: for, the further this work proceeds, the more subjects it makes for new business of the like kind.

To descend in particular to all these is impossible. And, to look further then the general heads of them, were superfluous and troublesome in this discourse; wherin I aim only at shew∣ing what sorts of things in common, may be done by Bodies: that, if hereafter we meet with things of another nature and strain, we may be sure they are not the off-spring of bodies and quantity; which is the main scope of what I have design'd here. And, to do this with confidence & certainty requires of necessity this leisurely and orderly proceeding we have hitherto used, and shall continue to the end. For, walking thus softly, we have always one foot upon the ground; so as the other may be sure of firm footing before it settle: Wheras, they, that for more hast will leap over rugged passages and broken ground, when both their feet are in the air, cannot help themselvs, but must light as chance throws them.

To this purpose, then, we may consider, that the qualities of bodies in common are of three sorts. For they are belonging, either to the Constitution of a compounded body, or else to the Operation of it; and the Operation of a body is of two kinds, one upon Other Bodies, the other upon Sense. The last of these three sorts of qualities shall be handled in a peculiar Chapter by themselvs. Those of the second sort, wherby they work upon, Other bodies, have been partly declar'd in the former chapters, and will be further discours'd of in the rest of this first Treatise. So as that which remains for the present is, to fall upon the dis∣course of such qualities as concur to the Constitution of bodies: with an aim to discover, whether (or no) they may be effected by the several mixtures of Rarity and Density, in such sort as is already declared. To which end, we are to consider in what manner these two primary differences of bodies may be joyn'd together; and what effects such conjuncton will produce.

As for their conjunction; to deliver the nature of it entirely, * 1.126 we must begin from the very root of it: and consider, how, the Universe, being finite (which Mr. White hath demonstrated, in the Second Knot of his First Dialogue), there cannot be an Infinite Number of Bodies in it; for Geometricians shew us, how the least

quantity that is may be repeated so often, as would exceed any the greatest determinate quantity whatever. Out of which it follows, that, although all the other bodies of the world were no bigger then the least quantity that can be designed; yet they, being infinite in number, would be greater then the whole Uni∣verse that contains them. Therfore, of necessity there must be some least body, or rather, some least size of bodies. Which in compounded bodies is not to be expected; for, their least parts, being compounded, must needs include compounding parts less then themselvs. We must then look for this least size of bodies in the Elements; which of all bodies are the simplest: And, among them, we must pitch upon that, wherein is greatest divisibility, & which consequently is divided into least parts; that is, Fire, So as, we may conclude that, among all the bodies in the world, that which of its own nature hath an aptitude to be least must be Fire.

Now, the least body of fire, be it never so little, is yet divisible * 1.127 into less. What is it then that makes it be one? To determine this, we must resort to the nature of Quantity; whose formal notion and essence is. To be divisible: which signifies, that many may be made of it. But, that of which many may be made is not yet many; out of this very reason, that many may be made of it. But, what is not many is one. Therfore what hath quantity, is, by mere having quantity, actually and formally as well one, as it hath the possibility of being made many, and consequent∣ly, the least body of fire, by having quantity, has those parts, which might be many, actually one. And this is the first con∣junction of parts that is to be consider'd in the composition of bodies: which, though it be not an actual joyning of actual parts, yet is a formal conjunction of what may be many.

In the next place we may consider; how, seeing the least bodies * 1.128 that are be of fire, it must needs follow, that the least parts of the other Elements must be bigger then they: And consequently the possible parts of those least parts of the other Elements must have something to conserve them together, more then is found in fire. And this, because Elements are purely distinguish'd by ra∣rity and densiy, is straight concluded to be density. And thus we have found, that, as quantity is the cause of the possible parts being one, so density is the cause of the like parts sticking

together: which appears in the very definition of it; for, to be less divisible (which is the notion of density) speaks a resistance to division, or sticking together.

Now, let us examine how two parts of different Elements are * 1.129 joyn'd together, to make a compound. In this conjunction we find both the affects we have already touch'd: for two such parts must make one; and moreover, they must have some resistance to divisibility. The first of these effects we have already assign'd to the nature of quantity. And, it being the formal effect of quantity, it cannot (wherever it is found) have any other for∣mal cause then quantity: wherfore, either the two little parts of different Elements do not become one body; or if they do, we must agree 'tis by the nature of quantity, which works as much in Heterogeneal parts as Homogeneal. And it must needs do so: because Rarity and Density (which are the proper dif∣ferences of Quantity) cannot change the common nature of Quantity, their Genus; which, by being so to them, must be univocally in them both. And this effect comes precisely from the pure notion of the Genus; and consequently, must be seen as well in two parts of different natures, as in two parts of the same nature: but, in parts of the same nature which once were two and and afterwards become one, there can be no o∣ther reason why they are one, then the very same for which those parts that were never separated (but that may be sepa∣rated) are likewise one: and this, most evidently, is the nature of quantity.

Experience seems to confirm thus much; when, pouring wa∣ter out of a basin, some of it will remain sticking to the sides of the metal. For if the quantity of the basin, and of the water, had not been one and the same by its own nature, the water (considering the pliableness of its parts) would certainly have come all away and glided from the unevenness of the basin, by the attractive unity of its whole; and would have preserv'd the unity of its quantity within it self, rather then, by sticking to the basin, have suffer'd division in its own quantity; which we are sure was one, whiles the water was altogether in the basin. But that, both the basin and the water making but one quantity, and a division being unavoydable in that one quanti∣ty; it was indifferent, in regard of the quantity consider'd singly

by it self, where this division should be made, whether in the parts of the basin, or in the parts of the water: and then, the o∣ther circumstances determin'd it, in that part of the water which was nearest to the joyning of it with the basin.

The second effect (which was, resistance to divisibility) we assign'd to density. And of that same cause must also depend the like effect, in this case of the sticking together of the two parts of different Elements, when they are joyn'd to one another, For, if the two parts, whereof one is dense the other rare, doe not exceed the quantity of some other part of one Homogeneal rare Element; for the dividing wherof such a determinate force, and no less, can suffice: then, seeing that the whole composed of these two parts is not so divisible, as the whole consisting of that one part; the assign'd force will not be able to divide them. Wherefore 'tis plain, that if the rare part had been joyn'd to a∣nother rare part, instead of the dense one it is joyn'd to; it had been more easily dividable from that, then now it is from the dense part: And by consequence, it stickes more closely to the dense part, then it would to another of its own nature.

Out of what we have said, a step is made us to understand why soft and liquid bodies easily joyn and incorporate into * 1.130 one continued body; but hard and dry bodies so difficultly, as by experience we find to be true. Water with water, or wine either with other wine, or with water, so unites, that 'tis very hard to part them: but sand or stones cannot be made to stick toge∣ther, without very great force and industry. The reasons where∣of must necessarily depend of what we have said above. To wit, that two bodies cannot touch one another, without becoming one: and that, if two bodies of one degree of density do touch, they must stick together according to the force of that degree of density. Out of which two is manifestly infer'd, that, if two hard things should come to touch, they must needs be more dif∣ficultly separated then two liquid things. And consequently, they cannot come to touch, without as much difficulty, as that wher∣by they are made one. * 1.131

But, to deduce this more particularly; let us consider, that all the little surfaces, by which one hard body may be conceiv'd to touch another (as for example, when a stone lies upon a stone), must of necessity be either plain, or concave, or convex. Now,

if a plain superficies should be supposed to touch another plain one coming perpendicularly to it; it must of necessity be grant∣ed to touch it as soon in the middle as on the sides. Wherfore, if there were any air (as of necessity there must be) betwixt the two surfaces before they touch'd; it will follow, that the air, which was in the midle, must have fled quite out from between the two surfaces, as soon as any part of the surfaces touch, that is, as soon as the air which was between the utmost edges of the surfaces did fly out; and, by consequence, it must have moved in an instant.

But, if a plain surface be said to touch a convex surface; it touches it only by a line (as Mathematicians demonstrate) or a point. But, to touch by a line or a point is, in truth, not to touch by the form or motion of Quantity, (which requires divisibili∣ty in all that belongs to it;) and by consequence among bodies it is not-to-touch: and so, one such surface doth not touch the other.

Now, for a plain surface to touch a concave, every man sees is impossible. Likewise, for two convex surfaces to touch one an∣other, they must be allow'd to touch either in a line or in a point which we have shew'd not to be a physical touching. And if a convex surface should be said to touch a concave, they must touch all at once, as we said of plain surfaces; and therfore the same impossibility will arise therein. So that 'tis evident, no two surfaces, moving perpendicularly towards one another, can come to touch one another; if neither of them yields, and changes its hew.

Now then, if it be supposed they come slidingly one over another in the same line; wherby, first, the very tips of the edges come to touch one another; and still as you shove the upper∣most on forwards, and it slides over more of the nether surface, it gains to touch more of it: I say that, neither in this case; do they touch immediately one another. For, as soon as the two first parts should meet, if they did touch and there were no air be∣tween them, they must presently become one quantity or body, as we have declared; and must stick firmly together, according to their degree of density; and consequenly, could not be moved on, without still breaking asunder at every impulse as much of the massie body, as were already made one by their touching.

And, if you should say they did not become one; and yet al∣low them to touch immediately one another, without having any air or fluid body between them: then, if you suppose them to move onwards upon these terms, they would be changed locally, without any intrinsecal change; which, in the book De Mundo (as we have formerly alledg'd) is demonstrated im∣possible.

There remains only a third way for two hard surfaces to come together, which is, that first they should rest sloping one upon another, and make an angle where they meet (as two lines that cut one another doe, in the point of their intersection); and so contain as it were a wedge of air between them: which wedge they should lessen by little and little, through their moving towards one another at their most distant edges (whiles the touching edges are like immoveable centers that the others turn upon); till at length they shut out all the air, and close to∣gether, like the two legs of a compass.

But neither is it possible that this way they should touch. For, after their first touch by one line, (which neither is, in effect, a touching, as we have shewed) no other parts of them can touch, though still they approach nearer and nearer; till their whole surfaces entirely touch at once: and therefore, the air must, in this case, leap out in an instant a greater space, then if the sur∣faces came perpendicularly to one another; for, here it must flie from one extremity to the other; whereas, in the former case, it was to go but from the middle to each side.

And thus 'tis evident, that no two bodies can arrive to touch one another; unless one of them at the least have a superficies ply∣able to the superficies of the other: that is, unless one of them be soft, which is, to be liquid in some degree. Seeing then, that by touching, bodies become one; and liquidity is the cause and means whereby bodies arrive to touch: we may boldly con∣clude, that two liquid bodies most easily and readily become one; and, next to two such, a liquid and a hard body are soon∣est united; but, two hard ones most difficultly.

To proceed then with our reflections upon the composition * 1.132 of Bodies, and upon what results out of the joyning and mixture of their first differences, Rarity and Density: we see, how, if a li∣quid substance happens to touch a dry body, it sticks easily

thereto. Then consider, there may be so small a quantity of such a liquid body, as it may be almost impossible for any na∣tural agent to divide it further into less parts; and suppose that such a liquid part is between two dry parts of a dense body, and, sticking to them both, becomes like a glew to hold them together: will it not follow, out of what we have said, that these two dense parts will be as hard to be severed from one another, as the small liquid part, by which they stick together, is to be divided? So that, when the viscuous ligaments, which, in a body hold together the dense parts, are so small and sub∣tile, as no force we can apply can divide them; the adhesion of the parts must needs grow then inseparable. And there∣fore, we use to moisten dry bodies, to make them more easily be divided; whereas those that are over-moist are, of them∣selves, ready to fall in pieces. And thus you see how, in gene∣ral, bodies are framed.

Out of which discourse, we may ballance the degrees of soli∣dity * 1.133 in bodies. For, all bodies being composed of humide and dry parts, we may conceive either kind of those parts to be bigger or lesser, or to be more rare or more dense. Now, if the dry parts of any body be extreme little and dense, and the moist parts that joyn the dry ones together be very great and rare; then, that bo∣dy will be very easie to be dissolv'd. But, if the moist parts, which glew together such extreme little and dense dry parts, be either lesser in bulk or not so rare; then the body composed of them will be in a stronger degree of consistence. And, if the moist parts which serve for this effect, be in an excess of littleness, and withal dense; then, the body they compose will be in the highest degree of consistence that nature can frame.

On the other side, if you glew together great dry parts, which are moderately dense & great, by the admixtion of humid parts that are of the least size in bulk, and dense withal; then the consistence will decrease from its height, by how much the parts are greater and the density less. But, if to dry parts of the greatest size, and in the greatest remisness of density, you add humid parts both very great and very rare; then the composed body will prove the most easily dissolveable of all that nature affords. * 1.134

After this, casting our eyes a little further towards the com∣position

of particular bodies; we shall find still greater mixtures the further we go: for, as the first and simplest compounded bo∣dies are made of the four Elements, so, others are made of these, and again a third sort of them; and so on-wards, according as by motion, the parts of every one are broken in sunder, and ming∣led with others. Those of the first order must be of various tem∣pers; according to the proportions of the Elements whereof they are immediatly made. As for example, such a proportion of Fire to the other three Elements will make one kind of sim∣ple body; and another proportion will make another kind: and so throughout, by various combinations and proportions, among all the Elements.

In the effecting of which work, it will not be amiss to look a little upon nature; and observe how she mingles and tempers different bodies one with another, wherby she begets that great variety of creatures we see in the World, But, because the de∣grees of composition are infinite, according to the encrease of number, we will contain our selves within the common notions of excess in the four primary components: for, if we should de∣scend once to specifie any determinate proportions, we should endanger losing our selvs in a wood of particular natures; which belong not to us at present to examin. Then, taking the four Elements as materials to work upon, let us first consider how they may be varied, that differing compositions may result out of their mixtures. I conceive that all the ways of varying the Elements, in this regard, may be reduced to the several sizes of Bigness of the Parts of each Element, that enter into the composition of any body; and to the Number of those Parts: for certainly, no other can be imagin'd, unless it were variety of Figure.

But, that cannot be admited to belong, in any constant man∣ner, to those least particulars wherof bodies are framed: as if determinate figures were, in every degree of quantity, due to the natures of Elements, and therfore the Elements would conserve themselves in those figures, as well in their least atoms as mas∣sie bulk. For, seeing how these little parts are shuffled toge∣ther without any order; and that all liquids easily joyn, and take the figures which the dense ones give them; and that they again, justling one another, crush themselves into new shapes,

to which their mixture with the liquid ones makes them yield the more easily: tis impossible the elements should have any other natural figure in these their least parts, then such as chance gives them. But, that one part must be bigger then another, is evident: for, the nature of rarity and density gives it; the first of them causing divisibility into little parts, and the latter hin∣dring it.

Having then settled in what manner the Elements may be va∣ried, * 1.135 in the composition of bodies, let us now begin our mixture. In which, our ground to work upon must be Earth and Water. For, only these two are the Basis of permanent bodies, that suffer our senses to take hold of them, and submit themselvs to trial. Wheras, if we should make the predominant Element to be Air or Fire, and bring in the other two solid ones under their juris∣diction, only to make up the mixture; the compound resulting out of them would be either in continual consumption (as ordi∣nary fire is), or else through too much subtlety, imperceptible to our eyes or touch; & therfore not a fit subject for us to discourse of; especially, since the other two Elements afford us enough to speculate on. Peradventure our Smel might take some cogni∣sance of a body so composed, or the effect of it, taken in by re∣spiration, might in time shew it self upon our health: but it con∣cerns not us now to look so far; our design requires more mani∣able substances.

Of these then let Water be the first; and with it we will mingle * 1.136 the other three elements, in excess over one another, by turns, but stil all of them oversway'd by a predominant quantity of water: and then let us see what kind of bodies will result out of such proportions. First, if earth prevail above fire and air, and arrive next in proportion to the water: a body of such a com∣position must needs prove hardly liquid, and not easie to let its parts run a sunder; by reason of the great proportion of so dense a body as earth, that holds it together. Yet, some inclination it will have to fluidness, by reason the water is predominant over all; which also will make it be easily divisible, and give every lit∣tle resistance to any hard thing that shall be apply'd to make way through it. In a word, this mixture makes the constitution of Mud, Dirt, Honey, Butter, and such like things where the main parts are great ones. And such are the parts of earth and water, in themselvs,

Let the next proportion of excess, in a watry compound be of air; which, when it prevails, incorporates it self chiefly with * 1.137 earth; for the other Elements would not so well retain it. Now, because its parts are subtile, (by reason of the rarity it hath), and sticking, (because of its humidity); it drives the earth and water likewise into lesser parts. The result of such a mixture is, that the parts of a body compounded by it are close, catching, flowing slowly, glibb; and generally it will burn, and be easily converted into flame.

Of this kind are those we call Oyly or unctuous bodies; whose great parts are easily separated, that is, easily divisible in bulk,) but the small ones very hardly. Next, the smalness and well-working of the parts, by means of the airs penetrating every dense one and sticking close to every one of them and, consequently, joyning them without any unevenness, causes that there can be no ruggedness in it; and therfore, 'tis glibb: in like manner as we see plaister or starch become smooth, when they are well wrought. Then, the humidity of it causes it to be catching; and the shortness of every part makes that, where it sticks, it is not easily parted thence. Now, the rarity of air, next to fire, admits it to be (of all the other Elements) most ea∣sily brought to the height of fire, by the operation of fire upon it: And therfore, oyls are the proper food of that Element. And accordingly we see; if a drop of oyl be spill'd upon a sheet of paper, and the paper set on fire at a corner; as the fire comes near the oyl, the oyl will disperse and spread it self upon the paper to a broader compass then it had, because the heat rarifies it: and so, in Oyl it self, the fire, rarifying the air, makes it penetrate the earthy parts adjoynd to it more then it did; and so subtilizes them, till they be reduced to such a height as they are within the power of fire to communicate its own nature to them: and thus, it turns them into fire, and carries them up in its * 1.138 flame.

But, if fire be predominant over earth and air in a watry compound; it makes the body, so proportion'd, to be subtile, rare, penetrative, hot in operation, light in weight, and subject to burn. Of this kind are all sorts of wines, and distil'd Spirits, commonly called strong waters or Aquavites; in Latine, Aquae∣ardentes.

These will lose their virtues, meerly by remaining un∣cover'd in the air: for, fire doth not incorporate strongly with water; but, if it find means, raises it self into the air. As we see in the smoke of boyling water; which is nothing else but lit∣tle bodies of fire, that, entring into the water, rarifie some parts of it; but have no inclination to stay there, and therefore, as fast as they can get out, fly away: but, the humide parts of the water which they have rarified (being of a sticking nature) joyn themselves to them, and ascend in the air, as high as the fiery atomes have strength to carry them; which when it fails them, that smoke falls down in a dew, and so becomes water a∣gain as it was. All which one may easily discern, in a glasse-vessel of water set over the fire; in which one may observe the fire come in at the bottome, and presently swim up to the top like a little bubble, and immediately rise from thence in smoke; and that will at last convert it self into drops, and settle upon some solid substance thereabouts.

Of these fiery spirits some are so subtile, as of themselves they will vanish, and leave no residue of a body behind them: and Al∣chymists profess to make them so etherial and volatile, that, be∣ing pour'd out of a glass from some reasonable height, they shall never reach the ground; but before they come thither, be so rarified by that little motion, as they shall grow invisible like the air, and dispersing themselves all about in it, fill the cham∣ber * 1.139 with the smell of that body which can no longer be seen.

The last excess in watery bodies must be of water it self; which is, when so little a proportion of any of the other is min∣gled with it, as is hardly perceptible. Out of this composition arise all those several sorts of juices or liquors, we commonly call Waters: which, by their mixture with the other three Ele∣ments, * 1.140 have peculiar properties beyond simple Elemental wa∣ter. The general quality whereof we shall not need any fur∣ther to express; because, by what we have already said of water in common, they are sufficiently known,

In our next survey, we will take Earth for our ground to work upon, as hitherto we have done water: which, if in any body it be in the utmost excess beyond all the other three, then rocks and stones will grow out of it; whose driness and hardness may

assure us, that Earth sways in their composition, with the least allay that may be. Nor doth their lightness (in respect of some other earthy compositions) impeach this resolution: for, that proceeds from the greatness and multiplicity of pores, wher∣with their driness causes them to abound••; and hinders not, but that their real solid parts may be very heavy.

Now, if we mingle a considerable proportion of water with earth, so as to exceed the fire and air, but still inferiour to the * 1.141 earth; we shall poduce metals; whose great weight, with their ductility and malleability, plainly tells us, that the smallest of waters gross parts, are the glew that holds the earthy dense ones together; such weight belonging to earth, and that easie chang∣ing of parts being most proper to water. Quick-silver (that is, the general matter wherof all the metals are immediately com∣posed) gives us evidence hereof: for, fire works upon it, with the same effect as upon water. And the calcination of most of the metals proves, that fire can easily part and consume the glew by which they were closed and held together: which therfore must be rather of a watry then of an aiery substance. Likewise the glibness of Mercury, and of melted metals, with∣out catching or sticking to other substances, gives us to under∣stand, that this great temper of a moist Element with earth is water, and not air; and that the watry parts are comprised, and as it were shut up within the earthy ones: for, air catches and sticks notably to all things it touches, and will not be impri∣soned; the divisibility of it being excceeding great, though in never so short parts.

Now, if air mingles it self with earth, and be prodominant * 1.142 over water and fire; it makes such an oily and fat soil, as Hus∣bandmen account their best mould; which, receiving a better∣ment from the Sun & temperate heat, assures us of the concourse of the aire: for wherever such heat is, air cannot fail of accompanying, or being effected by it; and the richest of such earth (as pot-earth and marl) will, with much fire, grow more compacted, and stick closer together then it did; as we see in baking them into pots or fine bricks. Whereas, if water were the glew between the dense parts, fire would consume it and crumble them asunder; as it doth in those bodies it calcines. And, excesse of fire will bring them to vitrification; which still

confirms that air abounds in them: for, it is the nature of air to stick so close, where once it is kneaded in, as it cannot be sepa∣rated without extreme difficulty. And, to this purpose, the vis∣cuous holding together of the parts of glass, when it is melted, shews evidently that air abounds in vitrified bodies.

The last mixture we are to meddle with is, of fire with earth; * 1.143 in an over-ruling proportion over air and water. And this, I con∣ceive, produces those substāces, which we may term co-agulated juyces, and which the Latines call succi concreti: whose first o∣rigine seems to have been liquours, that have been afterwards dried by the force either of heat or cold. Of this nature are all kind of Salts, Niters, Sulfurs, and divers sorts of Bitumens. All which easily bewray the relicks and effects of fire left in them; some more, some less, according to their degrees.

And thus we have, in general, deduced from their causes the complexions of those bodies, whereof the bulk of the world, * 1.144 subjected to our use, consists; and which serve for the produ∣ction and nourishment of living creatures, both animal and ve∣getable. Not so exactly (I confess) nor so particularly, as the matter in it self, or as a Treatise confined to that subject, would require: yet, sufficiently for our intent. In the performance whereof, if more accurate searchers of nature shall find that we have peradventure, been mistaken in the minute delivering of some particular bodies complexion, their very correction (I dare boldly say) will justifie our principal scope; which is, to shew that all the great variety we see among bodies arises out of the commixion of the First Qualities, and of the Elements: for, they will not be able to correct us upon any other grounds then those we have laid.

As may easily be perceiv'd, if we cast a summary view upon the qualities of compounded bodies. All which we shall find to spring out of rarity and density, and to savour of their origine: for, the most manifest qualities of bodies may be reduced to cer∣tain pairs, opposite to one another. As namely, some are liquid and flowing, others are consistent; some are soft, others hard; some are fatty, viscuous, and smooth, others lean, gritty, and rough; some gross, others subtile; some tough, others brittle: and the like. Of which, the liquid, the soft, the fat, and the vis∣cuous, are so manifestly derived from rarity; that we need not

take any further pains to trace out their origine: and the like is of their contraries, from the contrary cause, to wit, of those bo∣dies that are consistent, hard, lean, and gritty; all which evi∣dently spring from density. As for smoothness, we have alrea∣dy shew'd how that proceeds from an airy or oily nature; and by consequence, from a certain degree of rarity: And there∣fore roughness (the contrary of it) must proceed from a pro∣portionable degree of density. Toughness is also a kind of du∣ctility, which we have reduced to watriness; that is, to another degree of rarity; and consequently brittleness must arise from the contrary degree of density. Lastly, grossness and subtil∣ness consist in a difficulty or facility to be divided into small parts; which appears to be nothing else, but a certain determi∣nation of rarity and density. And thus we see, how the several complexions of bodies are reduced to the four Elements that compound them: and the qualities of those bodies, to the two primary differences of quantitative things, by which the ele∣ments are diversified.

And, out of this discourse, it will be evident, that these com∣plexions * 1.145 and qualities, though in diverse degrees, must of neces∣sity be found wherever there is any variation in bodies. For, seeing there can be no variation in bodies, but by rarity and density; and that the pure degrees of rarity and density make heat, cold, moisture, and driness, and (in a word) the four Ele∣ments; 'tis evident, that, wherever there is variety of bodies, there must be the four Elements; though peradventure far un∣like these miked bodies which we call Elements. And again, be∣cause these Elements cannot consist without motion, and by motion they of necessity produce Mixed bodies, and forge out those Qualities which we come from explicating; it must by like necessity follow, that wherever there is any variety of active and passive bodies, there mixed bodies likewise must re∣side of the same kinds, and be indued with qualities of the like natures, as those we have treated of; though peradventure, such as are in other places of the world, remote from us, may be in a degree far different from ours.

Since then it cannot be denied, but that there must be notable variety of active and passive bodies, wherever there is light: neither can it be denied but that, in all those Great Bodies from

which light is reflected to us, there must be a like variety of complexions and qualities, and of bodies temper'd by them, as we find here in the Orb we live in. Which Systeme, how diffe∣rent it is from that which Aristotle and the most of the School have deliver'd us; as well in the evidencies of the proofs for its being so, as in the position and model of it: I leave to the pru∣dent Readers to consider and judge.

Out of what has been already said, 'tis not hard to discover * 1.146 in what manner the composition of bodies is made. In effecting which, the main hinge wheron that motion depends is fire or heat: as it likewise is in all other motions whatever. Now, because the composition of a mixed body proceeds, from the action of one simple body or element upon the others; it will not be amiss to declare, by some example, how this work passes for that purpose, let us examine how fire or heat works upon his fel∣lows.

By what we have formerly deliver'd, 'tis clear, that fire stream∣ing out from its centre, and diffusing it self abroad, so as to fill the circumference of a larger circle; it must needs follow, that the beams of it are most condens'd and compacted together near the centre, and, the further they stream from the centre, the more thin and rarified they must grow: yet this is with such moderati∣on, as we cannot any where discern that one beam doth not touch another; and therfore the distances must be very smal. Now, let us suppose that fire happens to be in a viscuous and te∣nacious body; and then consider what will happen in this case: of one side, the fire spreads it self abroad; on the other side, the parts of the tenacious body being moist (as I have formerly de∣termin'd), their edges on all hands will stick fast to the dry beams of the fire that pass between them. Then they, stretching wider and wider from one another, must needs draw with them the parts of that tenacious body which stick to them; and stretch them into a greater widness or largness then they enjoy'd be∣fore: from whence it follows that (seeing there is no other body near therabouts, but they two), either there must be a va∣cuity left, or else the tenacious body must hold and fill a greater space then it did before; and consequently, be more rare. Contrariwise, of any of the other elements be stronger then fire, the denser Elements break off from their continu'd stream the

little parts of fire, which were gotten into their greater parts; and, sticking on all sides about them, so enclose them, that they have no more semblance of fire: and, if afterwards by any ac∣cident there comes a great compression, they force them, to lose their natural rarity, and to become some other Element. Thus it fares with fire, both in acting and suffering. And the same course, we have in both these regards expressed of it passes likewise in the rest of the Elements; to the proportion of their contrarieties.

Hence it follows that, when fire meets with humidity in any body, it divides and subtilises it, and disperses it, gently and in a kind of equal manner through the whole body it is in, (if the operation of it be a natural and a gentle one): and so drives it into other parts; which at the same time it prepares to receive it, by subtilising likewise those parts. And thus, mo∣derate fire makes humour, in very smal parts, to incorporate it self, in an even or uninform manner, with the dry parts it meets with: which being done, whether the heat afterwards conti∣nues, or the cold succeeds in lieu of it, the effect must of necessi∣ty be, that the body thus compos'd be bound up and fastn'd; more or less, according to the proportion of the Matter 'tis made of, of the Agents that work upon it, and of the Time they employ about it. This is every day seen, in the ripening of fruits, and in other frequent works as well of art as of nature; and is so obvious and sensible to any reasonable observation, that tis needless to enlarge my self much upon this subject.

Only, it will not be amiss, for examples sake, to consider the progress of it in the composing or augmenting of metals, or * 1.147 earths of divers sorts. First, heat (as we have said) draws hu∣mour out of all the bodies it works on: then, if the extract∣ed humour be in quantity, and the steams of it happen to come together in some hollow place, fit to assemble them into greater parts; they are condens'd, and fall down in a li∣quid and running body. These streams being corporified, the body resulting out of them makes it self in the earth a channel to run in: and, if there be any loose parts in the channel, they mingle themselvs with the running liquor; and though there be none such, yet in time liquor it self loosens the channel all about, and imbibes into its own substance

the parts it raises. And thus, all of them, compacted together, roll along; till they tumble into some low place, out of which they cannot so easily get, to wander further. When they are thus settled, they the more easily receive into them and retain such heat, as is every where to be met withal, because it is diffu∣sed more or less through the earth. This heat, if it be sufficient, digests it into a solid body: the temper of cold likewise concur∣ring in its measure to this effect. And, according to the variety of the substances wherof the first liquor was made, and which it afterwards drew along with it; the body that results out of them is diversifyed. In confirmation of all which, they that deal in Mines tell us, they use to find metalls oftentimes mingled with stones: as also coagulated juyces with both, and earths of divers natures with all three; and they with it, and one with another among themselvs. And that, sometimes, they find the mines not yet consolidated and digested throughly into metal; when, by their experience knowing after how many years they will be ripe, they shut them up again till then.

Now, if the hollow place wherin the body stay'd (which at first was liquid and rolling) be not at once filled by it, but it takes up only part of it; and the same liquor continues afterwards to flow thither: then this body is augmented, and groweth bigger and bigger. And, though the liquors should come at several times, yet they become not therfore two several bodies, but both grow into one body: for, the wet parts of the adventiti∣tious liquor mollifie the sides of the body already baked; and, both of them being of a like temper and cognation, they easily stick and grow together.

Out of this discourse it follows evidently, that, in all sorts of compounded bodies whatever, there must of necessity be actual∣ly comprised sundry parts of divers natures: for otherwise, they would be but so many pure degrees of rarity and density; that is, they would be but so many pure Elements, and each of them have but one determinate virtue or operation.

CHAP. XV. Of the dissolution of mixed bodies.

THus much for composition of Bodies. Their dissolution is * 1.148 made three wayes; either by fire, or by water, or by some

outward violence. We will begin with examining how this last is done. To which end we may consider, that, the unity of any body consisting in the connexion of its parts; 'tis evident, the force of motion, if it be exercised upon them, must of necessity separate them; as we see, inbreaking, cutting, filing, drawing asun∣der, and the like.

All these motions because they are done by gross bodies, re∣quire great parts to work upon, & are easily discern'd how they work: so that it is not difficult to find the reason why some hard bodies break easily, and others with much ado. The first of which are called brittle, the others tough. For, if you mark it, all breaking requires that bending should precede: which on the one side compresses the parts of the bended body, and con∣denses them into a lesser room then they possess'd before; and on the other side stretches them out, and makes them take up more place. This requires some fluid or moveable substance to be within the body; else it could not be done; for, without such help the parts could not remove. Therfore, such hard bodies as have most fluid parts in them, are most flexible, that is, are toughest: and those whcih have fewest, though they become therby hard∣est to have impression made upon them, yet, if the force be able to do it, they rather yield to break then to bend; and thence are called brittle.

Out of this we may infer, that some bodies may be so sudden∣ly bent, as that therby they break afunder; wheras, if they were leisurely and gently dealt withal, they would take what play one desires. And likewise that there is no body (be it never so brittle and hard) but it will bend a little (and indeed more then one would expect), if it be wrought upon with time & dexteri∣ty: for, there is none but contains in it some liquid parts, more or less; even glass and brick. Upon which occasion I remember, how once, in a great storm of wind, I saw the high slender brick Chimneys of the Kings house at S. James's (one winter, when the Court lay there) bend from the wind like boughs, and shake ex∣ceedingly and totter. And, at other times I have seen some very high and pointy Spire Steeples do the like. And I have been assu∣red the like of the whole pile of a high castle, standing in a gul∣let in the course of the winde, (namely the castle of Wardour), who have often seen it shake notably in a fierce wind.

The reason of all which may be deduced out of what we have said above. For, since the bending of a body makes the spirits or humours within it to sally forth; 'tis clear, if the violence which forces it be not so sudden, nor the motion it receives so quick, but that the moisture may oose gently out, the body will bend stil more and more, as their absence gives it leave. But, if the motion wrought in it be too quick, then the spirits, not ha∣ving time allow'd them to go leisurely and gently out, force their prison, and break out with a violence, and so the body is snap'd in two.

Here peradventure some (remembring what we have said in * 1.149 another place, namly, that it is the shortness and littleness of the humid parts in a body which makes it stick together; and that this shortness may be in so high a degree, as nothing can come between the parts they glew together to divide them) may ask, how a very dense body of such a strain can be broken or divi∣ded? But the difficulty is not great: for since the humid parts, in whatever degree of shortness they be, must necessarily have stil some latitude; it cannot be doubted but there may be some force assign'd greater then their resistance can be. All the questi∣on is, how to apply it to work its effect upon so close a compacted body, in which peradventure the continuity of the humid parts that bind the others together may be so small, as no other body whatever (no, not fire) can go between them, so as to se∣parate part from part. At the worst, it cannot be doubted, but that the force may be so apply'd at the outside of that body, as to make the parts of it press and fight one against another; and at length, by multiplication of the force, constrain it to yield and suffer division. And this I conceive to be the con∣dition of gold and some precious stones: in which the ele∣ments are united by such little parts, as nothing but a civil war within themselvs (stir'd up by some subtile outward enemy, wherby they are made to tear their own bowels) could bring to passe their destruction.

But this way of dissolving such bodies more properly belongs to the next way of working upon them, by fire: yet the same is done, when some exteriour violence, pressing upon those parts it touches, makes them cut a way betwixt their next neighbours; and so, continuing the force, divide the whole body. As, when

the chisel or even the hammer with beating breaks gold asun∣der: for, it is neither the chisel nor the hammer, that doth that effect immediately; but they make those parts they touch cut the others that they are forced upon. As, I remember, hap'ned to a Gentleman, that stood by me (in a Sea-fight I was in) with a coat of mail upon his body; when, a bullet coming against a bony part in him, made a great wound, and shatter'd all the bones near where it struck, and yet the coat of mail was whole: it seems the little links of the mail, yielding to the bullets force, made their way into the flesh and to the bone.

But now 'tis time to come to the other two instuments of se∣paration of bodies; Fire and water: and to examine how they * 1.150 dissolve compounds. Of these two, the way of working of fire is the easiest and most apparant to be discerned. We may readily observe how it proceeds, if we but set a piece of wood on fire; in which it makes little holes, as if with bodkins it pierced it. So that the manner of its operation in common being plain, we need but reflect a little upon the several particular degrees of it. Some bodies it seems not to touch; as clothes made of Asbestus; which are only purifyed by it. Others it melts, but consumes not; as gold. Others it turns into powder, suddenly dissolving their body; as lead, and such metalls as are calcined by pure fire. O∣thers, again it separates into a greater number of differing parts; as into Spirits, Waters, Oyls, Salt, Earth and Glass: of which rank are all vegetables. And lastly, others it converts into pure fire; as strong Waters, or Aquavites (called Aquae ardentes), and some pure Oyls: for the smoak that is made by their setting on fire, and peradventure their salt, is so little as is scarce discernable. These are, in sum, the divisions which fire makes upon bodies, according to their nature, and its due application to them: for, by the help and mediation of other things, it may peradven∣ture work other effects.

Now, to examine a little in particular, how the same fire, in differing subjects, produces such different effects: Limus ut hic * 1.151 durescit, & haec ut c••ra liquescit, Uno eodemque igni;

We will consider the nature of every one of the subjects, apart by it self. First for the Asbestus 'tis clear, it is of a very dry substance; so that, to look upon it when it is broken into very little pieces, they seem to be little bundles of short hairs,

the liquidity within being so little as it affords the parts nei∣ther length nor breadth; and therefore fire meets with little there that it can dilate. But, what it cannot dilate it cannot se∣parate; nor carry away any thing of it, but what is accidentally adherent to the outsides of it: And so it seems only to pass through the pores, and cleanse the little thrids; but brings no detriment at all to the substance of it. In this I speak on∣ly of an ordinary fire: for, I doubt not but such a one it might be, as would perfectly calcine it.

The next body we spake of is Gold. This abounds so much in liquidity, that it stickes to the fire, if duly apply'd; but * 1.152 its humidity is so well united to its earthy parts, and so perfectly incorporated with them, as it cannot carry away one, without both: but both are too heavy a weight, for the little agile parts of fire to remove. Thus it is able to make Gold swell; as we see in melting it; in which, the Gold re∣ceives the fire into its bowels and retains it a long time with it: but, at its departure, it permits the fire to carry nothing away upon its wings; as is apparant, by the Golds no whit de∣cay of weight, after never so long fusion. And therefore, to have fire make any separation in Gold, requires the assistance of some other moist body; that, on the one side, may stick closely to the Gold, when the fire drives it into it; and, on the othe rside, may be capable of dilatation, by the action of the fire upon it. As, in some sort, we see in Strong Waters made of Salts, (being a pro∣per subject for the fire to dilate); which, by the assistance of fire, mingling themselves closely with little parts of the Gold, pull them away from their whole substance, and force them to bear them company in their journey upwards, in which multi∣tudes of little parts of fire concur to press on and hasten them: and so, the weight of gold being at length overcome by these two powerful Agents (whereof one supplies what the other wants), the whole substance of the metal is, in little a∣tomes, diffused through the whole body of the water. But, this is not truly a dissolution or separation of the substantial parts of Gold, one from another: 'tis only a corrosion, which brings it into a subtile powder, (when the water & salts are separated from it), much like what filing (though far smaller) or grinding of leaf gold upon a porphyre stone may reduce it into: for neither the

parts of the water nor of the fire, that make themselvs a way in∣to the body of the gold, are small and subtile enough to get be∣tween the parts that compose the essence of it; and therefore all they can attain to is, to divide it only in its quantity or bulk, not in the composition of its nature.

Yet, I intend not to deny, but this is possible to be arrived to; either by pure fire duly apply'd, or by some other assi∣stance; as, peradventure, by some kind of Mercury; which, be∣ing of a nearer cognation to Metals then any other Liquor is, may happily have a more powerful ingression into gold, then any other body whatever; and being withal very subject to rarefaction, may (after it is inter'd.) so perfectly penetrate the gold, as it may separate every least part of it, and so reduce it into an absolute calx. But, in this place, I explicate no more then what ordinarily passes; leaving the mysteries of this Art to those who profess it.

To go on, then, with what we have in hand. Lead hath abun∣dance * 1.153 of water overmingled with its earth; as appears by its easie yielding to be bent any way, and by its quiet standing bent in the same position that the force which bowed it leaves it in, And therefore the liquid parts of Lead, are easily separated from its dry and earthy ones: and, when it is melted, the very shaking of it causes the gross parts to descend, and many liquid ones to flie away with the fire; so that suddenly it is thus converted into powder. But, this powder is gross in respect of other me∣tals; unless this operation be often reiterated, or the fire more powerfully apply'd, then what is just enough to bring the body of the Lead into powder.

The next consideration of bodies that fire works upon is, of such as it divides into Spirits, Salts, Oyls, Waters, or Phlegms, * 1.154 and Earth. Now, these are not pure and simple parts of the dis∣solv'd body; but new compounded bodies made of the first, by the operation of heat. As Smoak is not pure water, but water and fire together; and therefore becomes not water but by coo∣ling, that is, by the fire flying away from it. So likewise those Spi∣rits, Salts, Oyls, and the rest, are but degrees of things which fire makes of diverse parts of the dissolved body; by separating them one from another, and incorporating it self with them. And so they are all of them compounded of the four Element, and are further resolvable into them.

Yet, I intend not to say, that there are not originally in the body, before its dissolution, some loose parts which have the pro∣perties of these bodies that are made by the fire in the dissolving of it: For seeing that nature works by the like instruments as art uses, she must need, in her excesses and defects, produce like bo∣dies to what art doth in dissolution; which operation of art is but a kind of excess in the progress of nature. But, my meaning is, that, in such dissolution, there are more of these parts made by the working of fire, then were in the body before.

Now, because this is the natural and most ordinary dissoluti∣on of things; let us see in particular how it is done. Suppose then that fire were, in a convenient manner, apply'd to a body that hath all sorts of parts in it; and, our own discourse will tell us, the first effect it works will be, that, as the subtile parts of fire di∣vide and pass through that body, they will adhere to the most subtile parts in it: which being most agile and least bound and incorporated to the bowels of the body, and lying, as 'twere, loosly scatter'd in it, the fire will carry them away with it. These, will be the first that are separated from the main body: which being retain'd in a fit receiver, will, by the coldness of the cir∣cumdant air, grow outwardly cool themselves, and become first a dew upon the sides of the glass, and then, still as they grow cooler, condense more and more, till at length they fall down congeal'd into a palpable liquor; which is composed (as you see) of the hotest parts of the body, mingled with the fire that car∣ried them out: and therfore this liquor is very inflamable, and easily turn'd into actual fire; as you see all Spirits and aquae ardentes of vegetables are.

The hot and loose parts being extracted, and the fire conti∣nuing and encreasing, those that will follow next are such as, though they be not of themselvs loose, yet are easiest to be made so; and are therfore most separable. These must be humide, and those little dry parts which are incorporated with the overflow∣ing humide ones in them (for no parts that we can arrive to are of one pure simple nature, but all mixed and composed of the four Elements in some proportion) must be held together with such gross glew as the fire may easily penetrate and separate them. And then the humide parts divided into little atoms stick to the lesser ones of the fire: which, by their multitude

of number and velocity of motion, supplying what they want of them in bulk, carry them away with them. And thus these Phlegmatick parts flie up with the fire, and are afterwards con∣geal'd into an insipide water: which, if it have any savour 'tis because the first ardent spirits are not totally separated from it; but some few of them remain in it, and give some little life to the whole body of that otherwise flat liquor.

Now, those parts which the fire separates next from the re∣maining body, after the fiery and watry ones are carryed away, must be such as it can work upon: and therfore must abound in humidity. But, since they stir not till the watry ones are gone, 'tis evident, they are composed of many dry parts strongly in∣corporated, and very subtilly mixed with the moist ones; and that both of them are exceeding small, and so closely and finely knit together, that the fire hath much ado to get between, and cut the thrids that tie them together: and therfore they require a very great force of fire to carry them up. Now the composi∣tion of these shewes them to be Aerial: and (together with the fire that is mingled with them) they congeal into that consistence which we call Oyl.

Lastly, it cannot be otherwise but that the fire, in all this while of continual application to the body it thus anatomises, hath harden'd &, as it were, rosted some parts into such greatness and driness as they will not flie, nor can be carried up with any mo∣derate heat. But, great quantity of fire, being mingled with the subtiler parts of his baked earth, makes them very pungent and acrimonious in tast: so that they are of the nature of ordinary Salt, and so called; and, by the help of water, may easily be separated from the more gross parts, which then remain a dead and useless earth.

By this discourse 'tis apparent, that fire has been the instru∣ment, which hath wrought all these parts of an entire body, into the forms they are in: for, whiles it carried away the fiery parts, it swel'd the watry ones; and, whiles it lifted up them, it digested the Aerial parts; and, whiles it drove up the Oyle, it baked the earth and salt. Again, all these retaining, for the most part, the proper nature of the substance from whence they are extracted; 'tis evident, that the substance is not dissolv'd, (for so the nature of the whole would be dissolv'd and quite destroy'd & extinguish'd

in every part) but that onely some parts, containing the whole substance, or rather the nature of the whole substance, in them, are separated fromo ther parts that have likewise the same na∣ture in them.

The third instrument for the separation and dissolution of bo∣dies * 1.155 is Water, whose proper matter to work upon is Salt: and it serves to supply what the fire could not perform; which is the se∣paration of the salt from the earth, in calcined bodies. All the other parts fire was able to sever; but, in these he hath so baked the little humidity he hath left in them with their much earth, as he cannot divide them any further: and so, though he incor∣porates himself with them, yet he can carry nothing away with him. If then pure water be put upon that chalk, the subtilest dry parts of it easily joyn to the supervenient moysture; and stick∣ing close to it, draw it down to them. But, because they are the lighter, it happens to them as when a man in a boat pulls the land to him; that comes not to him, but he removes himself and his boat to it: so these ascend in the water, as they dissolve. And the water, more and more penetrating them, and, by addi∣tion of its parts, making the humidity, which glews their earthy parts together, greater and greater, makes a wider and wider separation between those little earthy parts; and so imbues the whole body of the water with them, into which they are disper∣sed in little atomes. Those that are of biggest bulk remain low∣est in the water, and, in the same measure as their quantities dissolve into less and less, they ascend higher and higher; till at length the water is fully replenish'd with them, and they are diffused through the whole body of it: whiles the more gross and heavy earthy parts (having nothing in them to make a present combination between them and the water) fall down to the bottome, and settle under the water in dust.

In which, because earth alone predominates in a very great excess, we can expect no other virtue to be in it, but that which is proper to mere earth; to wit, driness and weight. Which ordinary Alchimists look not after; and therfore call it Terra damnata: but others find a fixing quality in it, by which they perform very admirable operations, Now, if you prove the impregnated water from the Terra damnata, and then eva∣porate

it, you will find a pure white substance remaining: Which by its bulk shews it self to be very earthy, and, by its pricking and corrasive taste, will inform you much fire is in it; and, by its easie dissolution in a moist place, that water had a great share in the production of it. And thus the salts of bodies are made and extracted.

Now, as water dissolves salt, so, by the incorporation and vir∣tue of that corrosive substance, it doth more then salt it self can * 1.156 do: for, having gotten acrimony and more weight, by the mix∣ture and dissolution of salt in it, it makes it self away into solide bodies, even into metalls, as we see in brass and iron, which are easily rusted by salt dissolving upon them. And, according as the salts are stronger, so this corrasive virtue encreases in them; even so much, as neither silver nor gold are free from their eat∣ing quality: But they, as well as the rest, are divided into most small parts, and made to swim in water; in such sort as we have explicated above, and wherof every ordinary Alchymist teaches the practise.

But this is not all: salts help as well to melt hard bodies and metalls, as to corrode them. For, fome fusible salts flowing upon them by the heat of the fire, and others dissolv'd by the steam, of the metal that incorporates with them, as soon as they are in flux, mingle with the natural juice of the metals, and penetrate deeper, then without them the fire could do, and swell them and make them fit to run.

These are the principal ways of the two last instruments in dis∣solving of bodies; taking each of them by it self. But there re∣mains * 1.157 one more of very great importance, as well in the works of nature as of art; in which, both the former are joyned and concur: and that is putrefaction. Whose way of working is, by gentle heat and moisture to wet and pierce the body it works upon; wherby 'tis made to swel: and the hot parts of it be∣ing loosen'd, they are at length drunk up and drown'd in the moist ones (from whence by fire they are easily separated, as we have already declared;) and those moist parts afterwards lea∣ving it, the substance remaines dry and falls in pieces, for want of the glew that held it together.

CHAP. XVI. An explication of certain Maxims, touching the operations and qualities of bodies: and whether the Elements be found pure in any part of the World.

OUt of what we have determin'd, concerning the natural * 1.158 actions of bodies, in their making and destroying one an∣other; 'tis easie to understand the right meaning of some terms, and the true reason of some maxims much used in the Schools. As first; when Philosophers attribute to all sorts of corporeal Agents a Sphere of Activity. The sense of that manner of ex∣pression, in fire, appears plainly, by what we have already de∣clared of the nature and manner of operation of that Ele∣ment.

And in like manner, if we consider, how the force of cold con∣sists in a compression of the body that is made cold; we may perceive that, if, in the cooled body, there be any subtile parts which can break forth from the rest, such compression wil make them do so. Especially, if the compression be of little parts of the compressed body within themselvs, as well as of the outward bulk of the whole body round about. For, at first, the compressi∣on of such causes▪ in the body where they are, little holes or pores in the places they are compressed & driven from: which pores they filled up, when they were dilated at their own natu∣ral liberty; But, being thus forcibly shrunk up into less room, af∣terwards they squees again out of their croud all such very loose and subtile parts (residing till then with them) as can find their way out from among them. And these subtile parts, that thus are deliver'd from the colds compressions, get first into the pores that, we have shew'd, were made by this compression. But, they cannot long stay there: for, the atoms of advenient cold that obsess the compressed body, do likewise, with all their force, throng ito those pores, and soon drive out the subtile guests they find there; because they are more in number, bigger in bulk, and more violent in their course then they. Who ther∣fore must yield to them the little channels and capacities they formerly took up. Out of which they are thrust with such an impetuositie, that they spin from them with a vehemence, as

Quick silver doth through leather, when, to purifie it or bring an Amalgame to a due consistence, it is strained through the sides of it.

Now these showrs or streams of atomes issuing from the com∣pressed body are on all sides round about it, at exceeding little distances; because the pores, out of which they are driven, are so likewise. And consequently, there they remain round about be∣sieging it, as though they would return to their original homes, as soon as the usurping strangers, that were too powerful for them, will give them leave. And, according to the multitude of them, and to the force with which they are driven out, the com∣pass they take up round about the compressed body is greater or lesser. Which besieging atomes are not so soon carried away by any exterior and accidental causes, but they are supplied by new emanations succeeding them out of the said compressed body.

Now, this which we have declared, by the example of cold compressing a particular body, happens in all bodies wher∣ever they be in the world. For, this being the unavoidable effect of heat and of cold, wherever they reside, (which are the active qualities, by whose means, not only fire and water and the other two Elements, but all other mixed bodies composed of the Elements, have their activity); and they being in all bodies whatever (as we have proved above); it follows evidently, that there is not a body in the world but has about it self an orbe of emanations, of the same nature which that body is of▪ Within the compass of which orbe when any other body comes, that re∣ceives an immutation by the little atomes whereof that orbe is composed; the advenient body seems to be affected, and as it were, replenished with the qualities of the body from whence they issue: Which is then said to work upon the body, that im∣bibes the emanations that flow from it. And, because this orbe (regularly speaking) is in the form of a Sphere; the passive body is said to be within the Sphere of the others activity.

Secondly, when Philosophers pronounce, that No corpore∣al nature can operari in distans; that is, that no body can work * 1.159 upon another remote from it, without working first upon the body that lies between them, which must continue and place up the operation from the agent to the patient. The reason and truth of this maxime is, in our Philosophy, evident. For, we having

shew'd, that action among bodies is performed, for the most part, by the emission of little parts out of one body into another; as also, that such little parts cannot stream from the body that is their fountain, and settle upon a remote body, without passing through the interjacent bodies, which must furnish them, as it were, with channels and pipes to convey them whither they are to go: it follows manifestly, that the active emissaries of the working body can never reach their distant mark, unless they be successively ferried over the medium that lies between them; in which they must needs leave impressions of their having been there, and so work upon it in their passe, and leave in it their qualities and complexions, as a payment for▪ their wastage over.

But, peradventure some may contend, that these invisible Ser∣jeants and workmen are too feeble and impotent, to perform those visible great effects we daily see: As, when fire, at the length, burns a board that has been a great while opposed to it, though it touch not the body of the fire; or when a loadstone draws to it a great weight of Iron that is distant from it.

To whom we shall reply, that, if he will not grant these * 1.160 subtile emanations from the agent body to be the immediate workers of these effects, he must allot that efficacy to the whole corpulency of all the Agent working in bulk, (for, besides the whole & the parts, there is no third thing to be consider'd in bo∣dies, since they are constituted by quantity): But the whole can∣not work, otherwise then by local motion; which in this case it cannot do, because, by the supposition, it is determin'd to keep its distance from the passive body, and not to move towards it: Therfore, this is impossible; whereas the other can appear but difficult at the worst, and therefore must be admitted, when no better and more intelligible solution can be found.

But, withal we must note, that it is not our intention to say, but it may, in some circumstances, happen that some particular action or effect may be wrought in a remote part or body; which shall not be the same in the intermediate body that lies between the agent and the patient, and conveyes the agents working atomes to the others body. As for example, when tinder or Naph∣tha is, by fire, made to burn at a yard distance from it, when the interjacent air is but warm'd by that fire: Or, when the Sun, by means of a burning-glass or some other reflection, sets

some bodies on fire; and yet only enlightens the glass and the air that are in the way. The reason of which is manifest to be the divers dispositions of the different subjects, in regard of the Agent: and therfore 'tis no wonder that divers effects should be produced, according to those divers dispositions.

A third position among Philosophers is, that All bodies * 1.161 which work upon others, at the same time, suffer from those they work upon: and contrariwise, all bodies which suffer from others, at the same time, work back again upon them. For the better understanding wherof, let us consider, that all action among bodies is, either purely local motion, or else local motion with certain particularities, which give it a particular name. As, when we express the local motion of little atomes of fire, or of earth, or water, upon and into o∣ther bodies, by the words of heating or cooling; and so of the like. Now, if the action be pure local mo••on, and conse∣quently, the effect produced by that action be meerly change of place; we must call to mind, how two dense bodies, moving one against the other, each of them bear before them some little quantity of a rarer body immediately joyn'd to them: and consequently, these more rare bodies must be the first to feel the power of the dense bodies and receive impressions from their motions; each of them by the opposite rare body, which, like an Huissier goes before, to make way for his following Master that obliges him to this service.

Now, when these rare Ushers have strugled a while, like the first lightly armed Ranks of two Armies, in the interjacent Field between their main Battails, that follow them close at the heels; they must at the length yield, when they are overborn by a grea∣ter weight then they can sustain; and then they recoil back, as it were, to save themselves by getting in among the files of the dense bodies that drove them on. Which not opening to admit them, and yet they still flying violently from the mastering force that pursues them; they presse so hard upon what at the first pressed them on, as, notwithstanding their density and strength, they force them to retire back: for, unless they do so, they are not of the number of those that work upon one another. And, this retiring is either on both sides, or but of one side. If both; then 'tis evident how each of them is an Agent, and each

of them a sufferer; each of them overcoming his opposite in such sort, as himself likewise receives blows and loss. But, if only one of the dense bodies be so shocked as to recoil back; then that only suffers in its body, and the other suffers only in its vertue, that is, in the air or other rare body it sends before it: which it drives with such a violence, that it masters and quells the opposition of the other body, before it can reach to shake the dense body, before which it runs. Yet that rare bo∣dy must be pressed and broken into, in some measure, by the in∣counter of the other, (which though never so weak yet makes some resistance); but much more when it comes to grapple with the dense body it self: and so, between them, it is wounded and infeebled, like those souldiers that first enter a Breach in a Town, from whence when they have driven the enemy, they pursue him to the Cittadel, and force him from thence too; and so, how mai∣med so ever they prove, they make a free and easie way without resistance for the whole body of their army to follow them, and take quiet possession of that which cost them so much to win.

And thus we see how it may happen, that one of these moving bodies doth not suffer so much as to be stay'd in its journey; much less, to be driven back: And yet the other body, at the same time, work in some measure upon it, by working upon what is next to it; which recoiling against it, must needs make some im∣pression upon it, since there can be no opposition but must have some effect. Now this impression or effect, though it be not per∣ceptible by causing a contrary motion, yet it must needs in∣feeble the virtue of the conquering Agent, and deaden the cele∣rity of its motion. And thus it is evident, that, in all pure local motions of corporeal Agents, every one of them must, in some * 1.162 proportion, suffer in acting: and in suffering must act.

And, what we have said of this kind of action may easily be apply'd to the other, where the effect of local motion is de∣sign'd by a particular name; as it is in the examples we gave of heating and cooling. And, in that, the proceeding will appear to be the very same as in this: For, if fire heats water, the water reacts again, either upon the fire and cools it, if it be imme∣diate to it; or else upon the interjacent air, if it be at a distance from the fire. And so the air is in some measure cooled, by the cold atomes that issue from the water; whose compass or sphere

of activity being lesser then the fire's, they cannot cool so far off as others can heat; but, where they a rrive, they give their proportion of cold, in the very midst of the others army of fiery atomes, notwithstanding their multitude and violence.

According to which doctrine, our Countryman Suisseth's ar∣gument, that in the Schools is held insoluble, hath not so much as any semblance of the least difficult. For 'tis evident, that such atomes of fire and water, as we determine heat and cold to be, may pass and croud by one another into the subjects they are sent to, by divers little streams, without hindring one another (as we have declared of air and light); and each of them be re∣ceiv'd, in their own nature & temper, by the same subject; though sense can judge only according to which of them is predomi∣nant, and according to the proportion of its superiority.

Upon which occasion we cannot chuse but note, how the do∣ctrine of qualities is not only unable to give account of the or∣dinary and plain effects of nature; but also uses to end in clear impossibilities and contradictions, if it be driven far: as this ar∣gument of Suisseth shews, and many others of the like nature.

A fourth position among Philosophers is, that Some Notions * 1.163 admit the denominations of Intention and remission, but that others do not. The reason of which we shall clearly see, if we but consider how, these terms of intention and remission do but ex∣press more or less of the thing that is said to be intended or re∣mitted: for the nature of more and less implyes a latitude and divisibility; and therefore cannot agree with the nature of such things as consist in an indivisible being. As for example, to be a whole or an equal cannot be sometimes more, sometimes less; for, they consist in such a rigorous indivisible being, that, if the least part imaginable be wanting, it is no longer a whole, & if there be the least excess between two things, they are no longer equal, but in some other proportion then of equality, in regard of one another.

And hence it is that Aristotle teaches us that Substance and the species of Quantity do not admit of intention and remission; but that Quality doth. For first, in Substance, we know that the signification of this word is, that which makes a thing be what it is; as is evident by our giving it for an answer to the question what a thing is. And therfore, if there were any divisibility

in Substance, it would be in what the thing is; and consequently, every division following that divisibility, would make the thing another what, that is another thing: and so the Substance that's pretended to be changed by intension or remission, would not be divided, as is supposed; but would cease to be, and another sub∣stance would succeed in the room of it. Wherby you see that every mutation in Substance makes a new thing; and that more and less in quiddity cannot be pronounced of the same thing.

Likewise in Quantity, 'tis clear, that its Specieses consist in an indivsible. For, as in Numbers, ten Lions (for example) or ten Elephants are no more in regard of multitude, then ten Fleas or ten Motes in the Sun; and, if you add or take any thing from ten, it is no more ten, but some other number: so likewise in Continued extension, a span, an ell, an ounce, or any other mea∣sure whatever, ceaseth to be a span, &c. if you add to it or dimi∣nish from it the least quantity imaginable. And peradventure, the same is also of Figures; as of a Sphere, a Cube, a Circle, a Square, &c. though they be in the rank of Qualites.

But, if we consider such Qualities, as Heat, Cold, Moisture, Driness, Softness, Hardness, Weight, Lightness, and the like; we shall find that they may be in any body, somtims more, somtimes less (according as the excess of any Element or mixture is grea∣ter in it, at one time then at another): and yet the body, in which these qualities are intended or remitted, remain still with the same denomination. As, when Dirt continues still soft, though sometimes it be less soft, other whiles softer; and wax re∣mains figurable, whether it be melted or congealed; and wood is still hot though it lose or gain some degrees of heat.

But such intention in any subject whatever hath its determi∣nate limits, that it cannot pass; for when more of that quality which we say is intended (that is, more of the atoms of the active body) is brought into the body that suffers the intension, then its complexion can brook; it resigns its nature to their violence, and becomes a new thing, such an one as they are pleased to make it. As when wood, with extremity of heating (that is, with bring∣ing into it so many atoms of fire, that the fire is wronger in it then its own nature) is converted into fire, smoak, water, and ashes; and nothing remains of the nature of wood.

But, before we end this Chapter, we may remember how, in the * 1.164

of the Fourth, we remitted a question concerning the Existence of the Elements (that is, whether in any places of the world there were any pure elements, either in bulk or in little parts): as be∣ing not ready to resolve it, till we had declared the manner of working of bodies one upon another. Here then will be a fit place to determine that; out of what we have discoursed concer∣ning the actions, wherby bodies are made and corrupted. For, considering the universal action of fire, that runs through all the bodies we have commerce withal, by reason of the Suns influ∣ence into them and operation upon them, with his light and beams, which reach far and near; and looking upon the effects we have shew'd follow thence: 'tis manifest, there cannot be any great quantity of any body whatever, in which fire is not in∣trinsecally mixed. And, on the other side, we see that, where fire is once mixed, 'tis very hard to separate it totally from thence. Again, we see it is impossible that pure fire should be conserved, without being adjoyn'd to some other body: both be∣cause of its violent nativity, still streaming forth with a great im∣petuosity; as also because it is so easily overcome by any obsi∣dent body, when it is dilated. And therfore, we may safely con∣clude, that no simple Element can consist in any great quantity, in this course of nature we live in and take a survey of. Neither doth it appear, to what purpose nature should have placed any such storehouses of Simples; seeing she can make all needful complexions, by the dissolutions of mixed bodies into other mix∣ed bodies favouring of the nature of the Elements, without need∣ing their purity to begin upon.

But, on the other side, it is as evident, that the Elements must remain pure in every compounded body, in such extreme small parts as we use to call atoms. For, if they did not, the variety of bodies would be nothing else, but so many degrees of rarity and density, or somany pure Homogeneal Elements; and not bodies composed of heterogeneal parts: and consequently would not be able to shew that variety of parts which we see in bodies, nor could produce the complicated effects which proced from them. And accordingly, we are sure that the least parts, which our sen∣ses can arrive to discover, have many varieties in them: even so much that a whole living creature (whose organical parts must needs be of exceeding different natures) may be so little, as, to

our eyes, to seem indivisible; we not distinguishing any diffe∣rence of parts in it without the help of a multiplying glass: as, in the least kind of mites, and in worms pick'd out of childrens hands, we daily experience. So as it is evident that no sensible part can be unmingled. But then again, when we call to mind how we have shew'd that the qualities, which we find in bodies, result out of the composition and mixtion of the Elements; we must needs conclude, that they must of necessity remain in their own essences in the mixed body: and so, out of the whole dis∣course, determine, that they are not there in any visible quantity, but in those least atoms that are too subtile for our senses to dis∣cern. Which position we do not understand so Metaphysically, as to say that their Substantial form remain actually in the mix∣ed body; but only that their accidental qualities are found in the compound: remitting that other question to Metaphysicians (those spiri••al Anatomists) to decide.

CHAP. XVII. Of Rarefaction and Condensation, the two first motions of particular bodies.

OUr intention in this discourse, concerning the natures and * 1.165 motions of bodies, aiming no further then at the discovery of what is or may be done by corporeal Agents; thereby to de∣termin what is the work of Immaterial and Spiritual Substan∣ces: it cannot be expected at our hands, that we should deliver here an entire and complete body of Natural Philosophy; But only take so much of it in our way, as is needful to carry us, with truth and evidence, to our journeys end. It belongs not, then, to us to meddle with those sublime contemplations, which search into the nature of the vast Universe, and determine the unity and limitation of it; and shew by what strings, and upon what pins and wheels and hinges, the whole World moves: and from thence ascend to an awful acknowledgment and humble admi∣ration of the Primary Cause; from whence, and of which, both the being of it, and the beginning of the first motion, and the continuance of all others proceed and depend.

Nor indeed vvould it be to any purpose, for any man to sail in

this Ocean, and begin a new voyage of navigation upon it: unless he were assured, he had ballast enough in his Ship, to make her sink deep into the water and carry her steddily through those unruly waves; and that he were furnish'd with skill & provision sufficient to go through, without either losing his course by steering after a wrong compass, or being forced back again with short and obscure relations of discoveries: since others, that went out before him, are return'd with a large ac∣count, to such as are able to understand and sum it up. Which * 1.166 surely our learned Countryman, and my best and most honoured Friend, and to whom of all men living I am most obliged (for to him I ow that little which I know; and what I have and shall set down in all this discourse, is but a few sparks kindled by me at his great fire), has both profoundly, and accutely, and in every regard judiciously performed, in his Dialogues of the World.

Our task then (in a lower strain, and more proportionate to so weak shoulders) is, to look no further then among those bo∣dies we converse with. Of which having declared by what course and Engines Nature governs their common motions, that are found even in the Elements, and from thence are deri∣ved to all bodies composed of them; we intend now to consider such motions as accompany divers particular bodies, and are much admired by whoever understands not the the causes of them.

To begin from the easiest and most connexed with the acti∣ons * 1.167 of the Elements; the handsel of our labour will light upon the motions of Rarefaction and Condensation, as they are the passions of mixed bodies. And first, for Rarefaction, we may re∣member how it proceeds originally from fire, and depends of heat; as is declared in the former Chapter: and, wherever we find Rarefaction, we may be confident the body which suffers it is not without fire working upon it. From hence we may ga∣ther, that when the Air imprison'd in a baloon or bladder swells against what contains it, and stretches its case, and seeks to break out: this effect must proceed from fire or heat (though we see not the fire) working either within the very bowels of the air, or without; by pressing upon what contains it, and so making it self a way to it.

And, that this latter way is able to work this effect may

be convinced, by the contrary effect from a contrary cause: for' take a bladder stretch'd out to its greatest extent by air shut up within it, and hang it in a cold place; you will see it presently contract it self into a less room, and the bladder will grow wrinckled and become too big for the air within it. But, for immediate proof of this position, we see that the addition of a very smal degree of heat rarifies the air in a Weather-glass, (the air receiving the impression of heat sooner then water); and so makes it extend it self into a greater place: and consequently, it presses upon the water, and forces it down into a less room then formerly it possessed. And likewise we see Quicksilver and other liquors, if they be shut up in glasses close stop'd and set in sufficient heat (and a little is sufficient for this effect) will swell and fill their glasses; and at the last break them, rather then not find a way to give themselvs more room: which is then grown too straight in the glass, by reason of the rarefaction of the li∣quors by the fire working upon them.

Now, again, that this effect may be wrought by the inward heat, that is inclosed in the bowels of the substance thus shut up, both reason and experience assure us. For, they teach us, that, if a body which is not extremely compacted, but that by its loos∣ness is easily divisible into little parts (such a one as Wine or other spiritual liquors) be inclosed in a vessel; the little atoms that perpetually move up and down in every space of the whole World, making their way through every body, will set on work the little parts (in the Wine, for example) to play their game: so that the hot and light parts (if they be many), not enduring to be compressed and kept in by the heavie and cold ones, seek to break out with force; and, till they can free themselvs from the dense ones that would imprison them, they carry them along with them, and make them swell out as well as themselvs.

Now, if they be kept in by the vessel, so that they have not play enough; they drive the dense ones (like so many little ham∣mers or wedges) against the sides of it, and at length break it, and so make themselvs way to a larger room: But, if they have vent, the more fiery hot spirits fly away, and leave the other grosser parts quiet and at rest. On the other side, if the hot and light parts in a liquor be not many nor very active, and the vessel be so ful that the parts have not free scope to remove

and make way for one another; there will not follow any great effect in this kind: as we see in Bottle Beer or Ale, that works little, unless there be some space left empty in the bottle. And again; if the vessel be very much too big for the li∣quor in it, the fiery parts find room, first to swel up the heavie ones, and at length to get out from them, though the vessel be close stopped; for they have scope enough to float up and down between the surface of the liquor, and the roof of the vessel.

And this is the reason that, if a little beer or small wine be left long in a great cask, be it never so close stop'd, it will in time grow dead. And then, if, at the opening of the bung (af∣ter the cask hath been long unstir'd), you hold a candle close to it, you shall, at the instant, see a flash of flame environing the vent. Which is no other thing, but the subtile spirits that, part∣ing from the beer or wine, have left it dead; and, flying abroad as soon as they are permited, are set on fire by the flame they meet with in their journey: as being more combustible (be∣cause more subtile) then that spirit of wine which is kept in form of liquor; and yet that likewise (though much grosser) is set on fire by the touch of flame: And this happens not only to Wine, and Beer, or Ale; but even to water. As dayly experience shews in the East Indian Ships, that, having been five or six yeers at Sea, when they open some of their casks of Thames Water in their return homewards (for they keep that water till the last, as being their best and most durable, and that grows lighter and purer, by the often purifyings through violent motions in storms, every one of which makes new gross and earthy parts fall down to the bottom, and other volatile ones ascend to the top); a flame is seen about their bungs, if a candle be near, as we said before of wine.

And to proceed, with confirming this doctrine by further ex∣perience, we dayly see that the little parts of heat, being agitated and brought into motion in any body, enter and pierce into o∣ther parts, and incorporate themselvs with them, and set them on fire, if they be capable therof; as we see in wet Hay or Flax, laid together in great quantity. And, if they be not capable of taking fire, then they carry them with them to the outside; &, when they can transport them no further, part flies away, & other part staies

with them: as we see in new Bear or Ale; and in must of wine; in which a substance, usually call'd the mother, is wrought up to the top.

Which in wine wil at the last be converted into Tartar; when the spirits that are very volatile are flown away, and leave those parts, from whence they have evaporated, more gross and earthy then the others, where the grosser and subtiler parts continue still mixed. but in Beer, or rather in ale, this mother (which in them we call Barm) wil continue longer in the same consistence, and with the same qualities: for, the spirits of it are not so fiery that they must presently leave the body they have incorporated themselvs with; nor are hot enough to bake it into a hard con∣sistence. And therfore Bakers make use of it to raise their bread; which neither will it do, unless it be kept from cold: both which are evident signs that it works in force of heat; and consequent∣ly, that it continues still a hot and light substance.

And again we see that, after wine or beer hath wrought once, a violent motion wil make it work a new: As is daily seen in great lightnings, and in thunder, and by much rocking of them. For, such motion rarifies, and consequently heats them; partly by se∣parating the little parts of the liquor, which were before as glew'd together, & therfore lay quietly, but now, by their pulling a sunder and the liquors growing therby more loose then it was, they have freedom to play up and down: and partly by beating one part against another, which breaks and divides them in∣to lesser atomes, and so brings some of them into the state of fire; which, you may remember, is nothing else but a body brought into such a degree of littleness and rarity of its parts.

And this is the reason why such hard and dry bodies as have an unctuous substance in them are, by motion, either easily set on fire, or at least fire is easily goten out of them. As happens in flints and divers other stones, which yields fire when they are strucken; and if presently after you smel to them, you shall perceive an odour of brimstone and burning: which is a cer∣tain signe that the motion converted into fire the natural Brim∣stone that was mingled withthe Flint, & whose denser parts were grown cold, and so stuck to the stone. And, in like manner, the Ivywood, and divers others, as also the Indian Canes (which from thence are called Firecanes) being rub'd with some other

stick of the same nature, if they be first very dry, will of them∣selvs set on fire: and the like will happen to Coach-wheels in in the Summer, if they be overheated with motion.

To conclude our discourse of Rarefaction, we may look a little * 1.168 into the power and efficacity of it; which is no where to be seen so clearly as in fire. And, as fire is the general cause of rarefacti∣on, so is it of all bodies the most rarified: And therfore 'tis no marvel if its effects be the greatest that are in nature; seeing 'tis the proper operation of the most active Element. The wonderful force of it we daily see in Thunder, in Guns, in Granado's, & in Mines; of which, continual experience as well as several Histo∣ries, witnesse little less then miracles. Leaving them to the re∣marks of curious persons, we wil only look into the way, by which so main effects proceed from causes that appear so slender.

'Tis evident that fire (as we have said before) dilates it self spherically; as nature shews us manifestly in bubbles of boyling * 1.169 water, and Milk, and generally of such substances as are of a viscuous composition: for, those bubbles, being round, assure us that the cause which made them did equally dilate them from the Centre to all parts. Now then, remembring the infinite mul∣tiplication which is in fire, we may conceive that, when a grain of Gun-powder is turn'd into it, there are so many little bub∣bles of a viscuous substance, one backing another with great ce∣lerity, as there are parts of fire more then there were of Gun-powder. And, if we make a computation of the number and ce∣lerity of these bubbles, we shall find that although every one of them single seem to be of an inconsiderable force, yet the whole number of them together will exceed the resistance of the bo∣dy move or broken by them: especially, if we note that, when hard substances have not time allow'd them to yield, they break the sooner. And then we shall not so much admire the extremi∣ties we see acted by these means.

Thus having look'd into the nature of Rarefaction, and trac'd the progress of it from the motion of the Sun & fire: in the next place we are to examine the nature of Condensation. And we shall oftentimes find it likewise aneffect of the same cause other∣wise working. For, there being two different ways to dry any wet thing, one, by taking away that juyce which makes a bo∣dy liquid, the other, by putting more drought to the wet bo∣dy,

that it may imbibe the moisture; this latter way doth, as well as the former, condense a body: for, by the close sticking of wet to dry, the most part of condensation is effected in com∣pounded bodies.

The first of these wayes properly and immediately proceeds from heat. For heat, entring into a body, incorporates it self with the moist and viscuous parts it findes there; as purging medicines do with humour they work on: which when the sto∣mack can no longer entertain, (by reason of their unruly mo∣tions in wrestling together), they are both ejected grappling with one another; and the place of their contention is thus, by the supervenience of a guest of a contrary nature (that will not stay long there), purged from the superabundance of the for∣mer ones that annoy'd it. Even so the fire, that is greedily drunk up by the watry and viscuous parts of a compounded body, and whose activity and restless nature will not endure to be long im∣prisoned there, quickly pierces quite through the body it enters into: and, after a while, streams out at an opposite side, as fast as it enters on the side next to it, and carries away with it those glewy parts it is incorporated with; and, by their absence, leaves the body they pa••t from dryer then at the first it was.

Which course we may observe in Syrops that are boyl'd to a consistence, and in broths that are consumed to a jelly: over which, whiles they are making by the fire under them, you see a great steam; which is the watry parts that, being incorporated with fire, fly away in smoke. Likewise, when the sea-water is con∣dens'd into salt, you see it is an effect of the Sun or fire, that ex∣hales or boyls away all the palpable moisture. And so, when wet cloathes are hang'd, either in the Sun or at the fire, we see a smoake about the cloathes, and heat within them; which being all drawn out from them, they become dry.

And this deserves a particular note, that, although they should be not quite dry, when you take them from the fire; yet, by that time they are cool, they will be dry: for, the fire that is in them when removed from the main stock of fire, flying away, carries with it the moisture that was incorporated with it. And therfore whiles they were hot, that is, whiles the fire was in them, they must also be moist; because the fire and the moisture were

grown to be one body; and could not become through dry with that measure of fire, (for more would have dry'd them, even whiles they were hot) until they were also grown through cold. And in like manner, Syrups Hydromels, Gellies, and the like, grow much thicker after they are taken off from the fire, than they were upon the fire; and much of their humidity flies away with the fire, in their cooling, wherby they lessen much of their quantity, even after the outward fire hath ceased from working upon them.

Now, if the moist parts that remain after the drying be, by the heat, well incorporated in the dry parts; and so occasion the * 1.170 dry parts to stick close together; then, that body is condensed, and will (to the proportion of it) be heavier in a less bulk; as we see that Metals are heavier than Stones.

Although this effect be, in those examples, wrought by heat; yet, generally speaking, it is more proper to cold: which is the Second Way of drying a moist body. As when, in Greenland, the extreme cold freeses the Whalefishes Beer into Ice; so that the stewards divide it with Axes and Wedges, and deliver their portions of drinks to their ships company, and their Shallops gings, in their bare hands: but, in the innermost part of the Butt, they find some quantity of very strong liquor; not inferiour to moderate spirit of Wine. At first, before custome had made it familiar to them, they wonder'd that, every time they drew at the tap, when first it came from their ships to the shore, (for the heat of the hold would not let it freese), no liquor would come, unless they new tap'd it with a longer gimlet: but, they thought that pains well recompen'd, by finding it in the tast to grow stronger and stronger; till, at last, their longest gimlets would bring nothing out, and yet the vessel not a quarter drawn off, which obliged them then to stave the Cask, that so they might make use of the substance that remain'd.

The reason of this is evident, That cold seeking to condense the beer, by mingling its dry and cold parts with it; those that would indure this mixture were imbibed and shrunk up by them: But the other rare and hot parts, that were squees'd out by the dense ones which enter'd to congeal the beer, and were forced into the middle of the vessel (which was the furthest part for them to retire to, from their invironing enemies) con∣serv'd

themselvs in their liquid form, in defiance of the assault∣ing cold; whiles their fellows, remaining by their departure more gross and earthy then they were before, yielded to the conquerour, they could not shift away from, and so were dry'd and condens'd in ice: which, when the Marriners thaw'd, they found like fair water, without any spirits in it or comforting heat to the stomack.

This manner of condensation, which we have described in the freezing of Beer, is the way most practis'd by nature; I mean, for immediate condensation (for condensation is, secondarily, wher∣ever there is rarefaction, which we have determin'd to be an ef∣fect of heat.) And the course of it is, that a multitude of earthy and dry bodies, being driven against any liquor, easily divide it, by means of their density, their driness, and their littleness (all which in this case accompany one another, and are by us determin'd to be powerful dividers): and when they are gotten into it, they partly suck into their own pores the wet and diffu∣sed parts of the liquid body; and partly they make them (when themselvs are full) stick fast to their dry sides, and become as a glew to hold themselves strongly together. And thus they dry up the liquor; and, by the natural pressing of gravity, contract it into a lesser room: No otherwise then when we force much wind or water into a bottle, and, by pressing it more and more, make it lye closser then of its own nature it would do; Or rather, as when ashes are mingled with water, both those substances stick so close to one another, that they take up less room the•• they did each apart.

This is the method of Frosts, and Snow, and Ice, both natural and artificial: For, in natural freezing, ordinarily the North or Northeast Wind, by its force, brings and drives into our liquors such earthy bodies, as it has gather'd from rocks cover'd with snow; which, being mix'd with the light vapours whereof the wind is made, easily find way into the liquors, and then they dry them into that consistence we call Ice. Which, in token of the wind it has in it, swims upon the water, and, in the vessel where it is made, rises higher then the water did wherof it is composed: and ordinarily it breaks from the sides of the vessel, so giving way to more wind to come in and freeze deeper and thicker.

But because Galileus (In his Discourses, Intorno alle cose che stanno in su l' accqua, pag. 4.) was of opinion, that Ice was water * 1.171 rarified, and not condens'd; we must not pass over this verity, without maintaining it against the opposition of so powerful an adversary. His arguments are, first, that Ice takes up more place then the water did of which it was made; which is against the nature of condensation. Secondly, that, quantity for quanti∣ty, Ice is lighter then water; wheras things that are more dense are proportionally more heavie. And lastly, that Ice swims in water; wheras we have aften taught, that the more dense de∣sends in the more rare.

Now, to reply to these arguments, we say first, that We would gladly know how he did to measure the quantity of the Ice, with the quantity of the Water of which it was made: and then, when he hath shew'd it, and shew'd withall that Ice holds more place then water, we must tell him, that his experiment concludes no∣thing against our doctrine; because there is an addition of o∣ther bodies mingled with the water to make Ice of it (as we touch'd above), and therefore that compound may well take up a greater place then the water alone did, and yet be denser then it, and the water also be denser then it was.

And, that other bodies do come into the water and are min∣gled with it is evident, out of the exceeding coldness of the aire, or some very old wind; one of which two never misses to reign, whenever the water freezes: and both of them argue great store of little earthy dry bodies abounding in them, which, sweeping over all those that ly in their way and course, must of necessity be mixed with such as give them admittance; which water doth very easily. And accordingly we see that when, in the freezing of water, the Ice grows any thing deep, it either shrinks about the borders, or at least lies very loose; so as we cannot doubt but there is a free passage more of such subtile bodies to get still to the water, and freez it deeper.

To his second argument, we ask? How he knows that Ice, quantity for quantity, is lighter then water? For though, of a Spunge that is ful of water, it be easie to know what the spunge weighs, and what the water that was soaked into it, because we can part the one of them from the other, and keep each apart to examine their weights; yet, to do the like between Ice and

water, if Ice be throughout full of air (as of necessity it must be) we believe impossible. And therfore it may be lighter in the bulk then water, by reason of the great pores caus'd in it, through the shrinking up of the parts of water together (which pores must then necessarily be fill'd with air), and yet every part by it self (in which no air is) be heavier then so much water.

And by this it appears that his last argument (grounded upon the the swiming of Ice in water) has no more force, then if he would prove that an iron or earthen dish were lighter, and consequently more rare, then water, because it swims upon it; which is an effect of the airs being contain'd in the belly of it (as it is in Ice), not a sign of the metals being more rare then water.

Wheras, on the contrary side, the proof is positive and clear for us: For, it cannot be denied, but the mingling of the wa∣ter with other bodies more dense then it must of necessity make the compound, & also the water it self, become more dense then it was alone. And accordingly we see, that Ice half thaw'd (for then much of the air is driven out, and the water begins to fill the pores wherin the air resided before) sinks to the bot∣tom: as an Iron dish with holes in it (wherby the water might get into it) would do. And besides, we see that water is more Diaphanous then Ice, and Ice more consistent then water. Ther∣fore I hope we shall be excused, if, in this particular, we be of a contrary opinion to this great personage.

But, to return to the thrid of our discourse. The same that passes here before us, passes also in the Sky with Snow, Hail, * 1.172 Rain, & Wind. Which that we may the better understand, let us consider how Winds are made: for they have a main influence into all the rest. When the Sun, by some particular occurrent, raises great multitudes of Atoms from some one place, and they, either by the attraction of the Sun or some other occasion, take their course a certain way; this motion of those atoms we call a wind: which, according to the continuance of the matter from whence these atoms rise, endures a longer or a shorter time, and goes a farther or a shorter way; like a river, or ra∣ther like those eruptions of waters, which, in the Northern parts of England, they call Gypsies, which break out at uncertain times, and upon uncertain causes, and flow likewise with

an uncertain duration. So these winds, being composed of bodies in a determinate proportion heavier then the air, run their course, from their height to the ground; where they are suppor∣ted (as water is by the floor of its channel) whiles they perform their carreer: that is, till they be wasted, either by the drawing of the Sun, or by their sticking and incorporating into grosser bo∣dies.

Some of these winds, according to the complexion of the body out of which they are extracted, are dry; as those which come from barren mountains cover'd with snow: others are moist; as those that come out of marrishy or watry places: others have other qualities, as of heat, or cold, of wholsomness, or unwhol∣somness, and the like; partly from the source, and partly from the bodies they are mingled within their way.

Such then being the nature and origine of wind, if a cold one meet in the air with that moist body wherof otherwise rain would have been made, it changes that moist body into Snow or into Hail; if a dry wind meet with a wet body, it makes it more dry, and so hinders the rain that was likely to be: but, if the wet body overcome the dry wind, it brings the wind down along with it; as we see when a showre of rain allays a great wind.

And that all this is so, experience will in some particulars in∣struct us, as well as reason, from whence the rest may be evident∣ly infer'd, For we see that those, who, in imitation of nature would convert water into Ice, take snow or ice & mingle it with some active dry body, that may force the cold parts of the snow from it: and then they set the water (in some fit vessel) in the way that those little bodies are to take; which, by that means entring into it, strait incorporate themselves therewith, and of a suden con∣vert it into ice. Which process you may easily try, by mingling Salt Armoniacke with snow; but, much more powerfully, by set∣ting the snow over the fire, whiles the glass of water to be con∣gealed stands in it, after the manner of an egg in salt. And thus fire it self, though it be the enemy & destroyer of all cold, is made the instrument of freezing. And the same reason holds in the cooling of wine with snow or ice, when, after it has been a competent time in the snow, they, whose charge it is, use to give the vessel that contains the wine three or four turns in the snow; so to mingle through the whole body of the wine the

cold receiv'd first but in the outward parts of it, and, by pressing, too make that without to have a more forcible ingression.

But, the whole doctrin of Meteors is so amply, so ingenious∣ly, and so exactly perform'd, by that never-enough-praised Gen∣tleman, Mounsir Des Cartes, in his Meteorological discourses; as I should wrong my self and my Reader, if I dwell any longer upon this subject. And whose Physical discourses; had they been divulged before I had entred upon this work, I am perswa∣ded would have excused the greatest part of my pains in delive∣ring the nature of bodies.

It were a fault to pass from treating of Condensation, without * 1.173 noting so ordinary an effect of it, as is the joyning together parts of the same body, or of divers bodies. In which we see, for the most part, that the solide bodies which are to be joyn'd together are, first either heated or moistned, that is, they are rarified: and then they are left to cold air or other cold bodies, to thicken and condense (as above we mentioned of Syrups and Jellies) and so they are brought to stick firmly together. In like manner we see that, when two metals are heated till they be al∣most brought to running, and then are pressed together by the hammer, they become one continued body. The like we see in glass, the like in wax, and in divers other things. Onthe contrary side, when a broken stone is to be pieced together, the pieces of it must be wetted, and the cement must be likewise moist∣ned; and then joyning them aptly, and drying them, they stick fast together. Glew is moistned, that it may, by drying after∣wards, hold pieces of wood together. And the Spectale-makers have a composition, which must be both heated and moistned, to joyn to handles of wood the glasses they are to grind. And broken glasses are cemented with cheese and chalk, or with garlick.

All these effects, our sense evidently shews us, arise out of condensation; but, to our reason it belongs to examine particu∣larly by what steps thy are perform'd. First, then, we know that heat subtilizes the little bodies which are in the pores of the heated body; and partly also it opens the pores of the body it self, if it be of a nature that permits it: as it seems those bodies are, which by heat are mollified or are liquofactable. Again, we know that moisture is more subtile to enter into small creeks,

then dry bodies are; especially when it is pressed: for then it will be divided into very little parts, and will fill up every little chinck; and nevertheless, if it be of a gross and viscuous nature, all the parts of it will stick together. Out of these two proper∣ties we have, that, since every body has a kind of orb of its own exhalations or vapours round about it self (as is before decla∣red); the vapours which are about one of the bodies will more strongly and solidly (that is, in more abundant and greater parts) enter into the pores of the other body against which it is pressed, when they are opened and dilated: and thus they be∣coming common to both bodies, by flowing from the one, and streaming into the other, and sticking to them both, will make them stick to one another. And then, as they grow cold & dry, these little parts shrink on both sides, and, by their shrinking, draw the bodies together; and withal leave greater pores, by their being compressed together, then were there when by heat and moysture they were dilated: into which pores the circum∣stant cold parts enter, and therby, as it were, wedge in the others; and consequently make them hold firmly tostether the bodies which they joyn.

But, if art or nature should apply to this juncture any liquor or vapour, which had the nature and power to insinuate it self more efficaciously to one of these bodier, then the glew which was between them did; of necessity in this case these bodies must fall in pieces. And so it happens in the separation of metals by corrosive waters; as also in the precipitation of metals or salts, when they are dissolv'd into such corrosive waters, by means of other metals or salts of a different nature: in both which cases, the entrance of a latter body, that penetrates more strongly, and unites it self to one of the joyn'd bodies but not to the other, * 1.174 tears them asunder, and that which the piercing body rejects falls into little pieces; and, if formerly it were joyn'd with the liquor, 'tis then precipitated down from it in a dust.

Out of which discourse we may resolve the question of that learned and ingenious man, Petrus Gassendus; who, by experi∣ence found, that water, impregnated to fulness with ordinary salt, would yet receive a quantity of other salt, and, when it would imbibe no more of that would neverthless take into it a proportion of a third, and so of several kinds of salts one af∣ter

another: which effect he attributed to Vacuities or porous spaces of divers figures, that he conceived to be in the water; wherof some were fit for the figure of one salt, and some for the figure of another. Very ingeniously; yet, if I miss not my mark, most assuredly he hath missed his.

For, first, how could he attribute divers sorts of Vacuities to water, without giving it divers figures? And this would be against his own discourse, by which every body should have one deter∣minate natural figure.

Secondly, I would ask him, if he measured his water after every salting? and, if he did, whether he did not find the quantity grea∣ter, then before that salt was dissolv'd in it? Which if he did, (as without doubt he must), then he might safely conclude that his salts were not receiv'd in vacuities; but that the very sub∣stance of the water, gave them place, and so encreas'd by the re∣ceiving them.

Thirdly, seeing that, in his doctrine, every substance has a par∣ticular figure; we must allow a strange multitude of diffe∣rent shapes of vacuities to be naturally in water, if we will have every different substance wherwith it may be impregnated (by making decoctions, extractions, solutions, and the like), to find a fit vacuity in the water to lodg it self in. What a difform net, with a strange variety of mashes, would this be? And indeed, how ex∣tremely uncapable must it be of the quantity of every various kind of vacuity that, you will find, must be in it; if in the dissolu∣tion of every particular substance, you calculate the proportion between it and the water that dissolveth it, and then multiply it according to the number of several kinds of substances that may be dissolved in water? By this proceeding, you will find the va∣cuities to exceed infinitely the whole body of the water; even so much that it could not afford subtile thrids enough to hold it self together.

Fourthly, if this doctrine were true, it would never happen that one body, or salt, should precipitate down to the bottom of the water, by the solution of another in it; which, every Alchymist knows, never fails in due circumstances: for, seeing that the bo∣dy which precipitates, and the other which remains dissolv'd in the water, are of different figures, and therfore require d••ffe∣rent vacuities; they might both of them have kept their places

in the water, without thrusting one another out of it.

Lastly, this doctrine gives no account, why one part of salt is separated from another, by being put in the water; and why the parts are there kept so separated: which is the whole effect of that motion we call dissolution.

The true reason therfore of this effect is (as I conceive), that * 1.175 one salt makes the water apt to receive another: for, the lighter salt, being incorporated with the water, makes the water more proper to stick to an heavier, and, by dividing the small parts of it, to bear them up, that otherwise would have sunk in it. The truth and reason of which will appear more plain; if at every joynt we observe the particular steps of every salts solution. As soon as you put the first salt into the water, it falls down pre∣sently to the bottome of it; and as the water by its humidity pierces by degrees the little joynts of this salt, so the small parts of it are by little and little separated from one another, and uni∣ted to parts of water. And so, infusing more and more salt, this progress will continue; till every part of water is incorporated with some part of salt: and then, the water can no longer work of it self, but in conjunction to the salt with which it is united. After which, if more salt of the same kind be put into the water, that water so impregnated will not be able to divide it; because it has not any so subtile parts left, as are able to enter between the joynts of a salt so closely compacted: but may be compared to that salt, as a thing of equal driness with it; and therfore is unapt to moisten and pierce it.

But, if you put into this compound of salt and water another kind of salt, that is of a stronger and drier nature then the for∣mer and whose parts are more grosly united; then, the first salt dissolv'd in the water will be able to get in betwixt the joynts of the grosser salt, and divide it into little parts: and will incor∣porate his already-composed parts of salt and water into a de∣compound of two salts and water; till all his parts be anew im∣pregnated with second grosser salt, as before, the pure water was with the first subtiler salt. And so it will proceed on, if pro∣portionate bodies be joyn'd; till the dissolving composition grow into a thick body.

To which discourse we may add, that, when the water is so fully impregnated with the first salt, as it will receive no more,

remaining in the temper 'tis in; yet, if it be heated, it will then afresh dissolve more of the same kind. Which shews, that the rea∣son of its giving over to dissolve is, for want of having the water divided into parts little enough to stick to more salt, which as, in this case, the fire doth, so peradventure in the other, the acrimoniousness of the salt doth it.

And this is sufficient to give curious wits occasion, by making * 1.176 further experiments, to Search out the truth of this matter. Only, we may note what happens in most of the experiencies we have mention'd; to wit, that things of the same nature joyn better and more easily, then others that are more estranged from one another. Which is very agreeable to reason; seeing that, if na∣ture intends to have things consist long together, she must fit them for such consistence.

Which seems to proceed out of their agreement in four qua∣lities. First, in weight; for bodies of divers degrees in weight, if they be at liberty, seek divers places: and consequently, sub∣stances of like weight must of necessity find one another out, and croud together, as we have shew'd, it is the nature of heat to make them do. Now, it is apparent, that things of one nature must, in equal parts, have the same or a near proportion ofweight; seeing that, in their composition, they must have the same pro∣portion of Elements.

The second reason, of the consistence of bodies together, that are of the same nature, is the agreement of their liquid parts, in the same degree of rarity and density. For, as it is the nature of quantity in common to make all parts be one quantity; so it is the nature of the degrees of quantity, when two parts meet that are of the same degree, to make them one in that degree of quantity: which is, to make them stick together, in that degree of sticking which the degree of density that is common to them both makes of its own nature. Wheras, parts of different densities cannot have this reason of sticking: though, peradventure they may, upon some other ground, have some more efficatious one. And in this manner, the like humide parts of two bodies, becom∣ming one, the holes or receptacles, in which those humide parts are contain'd, must also needs be united.

The third reason is the agreeable proportion, which their se∣veral figures have in respect of one another. For, if any humidi∣ty

be extracted out of a mixed body, especially, by the virtue of fire, it must have left pores of such figures, as the humidity that is drawn out of them is apt to be cut into: for every humide body (not being absolutely humide, but having certain dry parts mix∣ed with it) is more apt for one kind of figure and greatness, then for another; and by consequence, whenever that humidity shall meet again with the body it was severed from, it will easily run through and into it all, and fill exactly the cavities pores it passed before.

The last quality in which bodies that are to consist long toge∣ther agree is, the bigness of the humide & dry parts of the same body. For, if the humide parts be too big for the dry ones, 'tis clear that the dry ones must needs hang loosly together by them, because their glew is in too great a quantity: But, if the humide parts be too little for the dry ons, then of necessity some portion of every little dry part must be unfurnish of glew, by means wherof to stick to his fellow; and so the sticking parts not being conveniently proportion'd to one another, their adhesion can∣not be so solid, as if each of them were exactly fitted to his fellow.

CHAP. XVIII. Of another motion belonging to particular bodies, call'd Atraction; and of certain operations, term'd Magicall.

HAving thus ended the two motions of rarefaction and con∣densation; the next that offer themselvs are the locall mo∣tions, * 1.177 which some bodies have to others. These are somtimes perform'd by a plain force in the body towards which the mo∣tion is: and other whiles by a hidden cause, which is not so ea∣sily discern'd. The first is chiefly that which is ordinarily said to be done by the force of nature to hinder vacuum, and is much practis'd by nature: as, in drawing our breath, in sucking, and many other natural operations, which are imitated by art in making of Pumps, Syphons, and such other instuments: and in that admirable experiment of taking up a heavy Marble stone, merely by another lying flat and smoothly upon it, without any ther connexion of the two stones together, as also by that sport of boyes, when they spread a thin moistned leather upon a smooth broad stone, press it all over close to it, and then by pul∣ling of a string fastned at the middle of the leather, they draw up

likewise the heavy stone. In all which, the first cause of the mo∣tion proceeds from that body towards which the motion is made: and therfore is properly called Attraction.

For the better understanding and delaring of which, let us suppose two marble stones, very broad and exceeding smoothly polished, to be laid one flat upon the other: and let there be a ring fastned at the back part of the uppermost stone, and exactly in the middle of it. Then, by that ring, pull it up perpendicular∣ly and steadily; and the undermost will follow, sticking fast to the overmost: and though they were not very perfectly polished, yet the nethermost would follow for a while, if the ring be sud∣denly plucked up; but then it will soon fall down again. Now this plainly shews, that the cause of their sticking so strongly toge∣ther, when both the stones are very well polished, is for that no∣thing can well enter between them to part them; and so, 'tis re∣duced to the shortness of the air betwixt them: which not be∣ing capable of so great an expansion, nor admitting to be divi∣ded thick-ways, so much as is necessary to fill the first growing distance between the two stones till new air finds a course thi∣ther (that so the swelling of the one may hinder vacuity, till the other come into the rescue); the two stones must needs stick to∣gether to certain limits, which limits will depend of the pro∣portion that is between the weight, and the continuity of the nethermost stone.

And, when we have examin'd this, we shall understand in what sense it is meant that Nature abhors from Vacuity; and what * 1.178 means she uses to avoid it. For, to put it as an enemy that nature fights against, or to discourse of effects that would follow from it, in case it were admitted, is a great mistake, and a lost labour; seeing it is nothing and, therfore, can do nothing: but is meer∣ly a form of expression, to declare, in short, nothing else but that it is a contradiction, or implication in terms, and an impos∣sibility in nature, for Vacuity to have or be supposed to have a Being.

Thus then, since in our case, after we have cast all about, we can pitch upon nothing to be consider'd but that the two stones touch one another, and that they are weighty; we must apply our selvs only to reflect upon the affects proceeding from these two causes, their contiguity and their heaviness: and we shall find

that as the one of them, namely the weight, hinders the under∣most from following the uppermost, so, contiguity obliges it to that course; and according as the one overcoms the other, so will this action be continued or interrupted.

Now, that contiguity of substances makes one follow another, is evident, by what our Masters in Metaphysicks teach us; when they shew that, without this affect, no motion at all could be made in the world, nor any reason given for those motions we daily see. For, since the nature of quantity is such, that, when∣ever there is nothing between two parts of it, they must needs touch and adhere and joyn to one another; (for how should they be kept asunder, when there is nothing between them to to part them?) if you pull one part away, either some new sub∣stance must come to be close to that which removes; (or else the other, which was formerly close to it, must still be close to it, and so follow it: for, if nothing come between, it is still close to it. Thus then, it being necessary that somthing must be joyn'd close to every thing; Vacuity, (which is nothing) is excluded from having any being in nature.

And, when we say that one body must follow another, to avoid vacuity; the meaning is, that, under the necessity of a contra∣diction, they must follow one another, and that they cannot do otherwise. For it would be a contradiction, to say that nothing were between two things; and yet that they are not joyn'd close to one another: and therfore, if you should say it, you would in other words say, they are close together, and they are not close together. In like manner, to say that Vacuity is any where, is a pure contradiction; for Vacuity, being nothing has no Being at all: and yet, by those words, it is said to be in such a place; so that they affirm it to be and not to be, at the same time.

But now, let us examine if there be no means to avoid this contradiction and vacuity; other then by the adhesion, & follow∣ing * 1.179 of one body upon the motion of another, that is closely joyn'd to it and every where contiguous. For, sense is not easily quieted with such Metaphysical contemplations, that seem to re∣pugn against her dictamens; and therefore, for her satisfaction, we can do no less then give her leave to range about and cast all waies, in hope of finding some one that may better content her: which when she finds that she cannot, she will the less repine

to yield her assent to the rigorous sequels and proofs of reason.

In this difficulty then, after turning on every side, I for my part can discern no pretence of probability, in any other means but pulling down the lower stone by one corner; that so there may be a gaping between the two stones, to let in air by little and lit∣tle. And, in this case, you may say that, by the intervention of air, Vacuity is hinder'd; and yet the lower stone is left at liber∣ty to follow its own natural inclination, and be govern'd by its weight. But indeed, if you consider the matter well, you will find that the doing this requires a much greater force, then to have the lower stone follow the upper: for, it cannot gape in a straight line, to let in air, since, in that position, it must open at the bottom where the angle is made, at the same time that it o∣pens at the mouth: and then, air requiring time to pass from the edges to the bottom, it must in the mean while fal into the con∣tradiction of Vacuity. So that, if it should open to let in air, the stone, to compass that effect, must bend; in such sort as wood doth, when a wedg is put into it to cleave it.

Judge then what force it must be, that should make hard mar∣ble, of a great thickness, bend like a wand; and whether it would not rather break and slide off, then do so: you will allow that a much less will raise up the lower stone, together with the up∣permost. It must then of necessity fall out, that it will follow it, if it be moved perpendicularly upwards. And the like effect will be, though it should be raised at oblique angles; so that the low∣er-most edge do rest all the way upon somthing that may hinder the inferiour stone from sliding aside from the uppermost.

And this is the very case of all those other experiments of art and nature, which we have mention'd above: for, the reason holds as well in water and liquide things, as in solid bodies, till the weight of the liquid body overcome's the continuity of it; for then, the thrid breaks, and it will ascend no higher. * 1.180

Which height Galileo tells us (from the workmen in the Arsenal of Venice) is 40 foot; if the water be drawn up in a close pipe; in which the advantage of the sides helps the ascent. But others say that the invention is inlarged; and that water may be drawn to what height one pleases. However, the force which nature applies to maintain the continuity of quantity, can have no limit; seeing it is grounded upon contradiction.

And therefore Galileo was much mistaken, when he thought to make an instrument, wherby to discover the limits of this force.

We may then conclude, that the breaking of the water must depend from the strength of other causes. As for example, when the gravity is so great, by increasing the bulk of the water, that it will either overcome the strength of the pipe, or else make the sucker of the pump rather yield way to air, then draw up so great a weight: for which defects, if remedies be found, the art may surely be inlarged without end.

This is particular in a Syphon, that, when that arm of it, which hangs out of the water, is lower then the superficies of the water; * 1.181 then, it will run of it self, after it is once set on running by suck∣ing. The reason whereof is, because the weight, which is in the water pendant, is greater then the weight of the ascending wa∣ter; and therby supplyes the want of a continual sucke••. But, if the nose of that arm that hangs out of the water be put even with the water; then the water will stand still in both pipes or arms of the Syphon, after thy are filled with sucking. But, if, by the running out of the water, the outward pipe grow shorter then to reach as low as the superficies of the water in the fountain from whence it runs; in this case, the water in each arm of the Syphon will run back into the fountain.

Withall it is to be noted, that, though the arm which is out of the water be never so long, yet, if it reach not lower then the superficies of the fountain, the over quantity and weight of the water there, more then in the other arm, helps it nothing to make it run out. Which is, because the declivity of the other arm over-recompences this overweight. Not that the weight in the shorter pipe has so much force, as the weight in the longer pipe; but because it has more force then the greater weight exercises therin its running: for, the greatest part of its force, tends another way, then to the end of the pipe, to wit, perpendi∣cularly towards the Centre; and so is hindred from effect, by the great sloping, or little declivity, of the pipe upon which it leans. * 1.182

But, some, considering how the water in that longer arm of the Syphon is more in quantity, than the water in the other arm of it, wherat it runs out, admire why the greater quantity of wa∣ter doth no••d raw back the less into the cistern; but suffers it

self to be lifted up, and drain'd away, as if it run steeply down∣wards. And they imagine, that hence may be deduced, that the parts of water in the cistern do not weigh, as long as they are within the orb of their own body.

To whom we answer, that they should consider how, that to have the greater quantity of water in the longer arme of the Syphon (which arm is immersed in the water of the cistern) draw back into the cistern the water in the other arm of the Syphon, that hangs out in the air; it must both raise as much of the water of the cistern as its own bulk is, above the level which at present the whole bulk of water has, and withal, at the same time, pull up the water in the other arm. Now 'tis mani∣fest, that these two quantities of water together are heavier then the water in the sunk arm of the Syphon; since one of them single is equal unto it: And by consequence, the more water in the sunk arm cannot weigh back the less water in the hang∣ing arm; since, to do that, it must at the same time weigh up, over and above, as much more in the cistern as it self weighs.

But, turning the argument, I say, that, if once the arm of the Syphon that is in the air be supposed to draw any water, be it never so little, out of the cistern (whether occasioned by suck∣ing or by whatever other means): it follows that as much water as is drawn up, above the level of the whole bulk in the cistern, must needs press into the sunken arm from the next adjacent parts, (that is, from the bottom) to supply its emptying; and as much must of it self press down from above (according to its natural course, when nothing violents it) to rest in the place, that the ascending water, (which is lower then it) leavs at liber∣ty for it to take possession of. And then it cannot be doubted, but that this descending water, having all its weight in pressing down applied to drive up the rising water in the sunk arm of the Sy∣phon, & the water in the other arm of the Syphon without ha∣ving all its weight in rūning out appli'd at the same time to draw up the same water in the sunk arm; this single resistant must yield to their double & mastering force. And consequently, the water in the arm of the Syphon that is in the air must needs draw the water that is the other immersed arm, as long as the end of its pipe reaches lower then the level of the water in the cistern; for so

long, it appears by what we have said, it must needs be more weighty, since part of the rising water in the sunk arm of the sy∣phon is coū erpois'd by as much descending water in the cistern.

And thus 'tis evident, that, out of this experiment, it cannot be infer'd, that parts of water do not weigh within the orb of their own whole: but only, that two equal parts of water in their own orb (namely that which rises in the sunken arm, and that which presses down from the whole bulke in the cistern) are of equal weight and ballance one another, So that never so little odds, between the two counterpoysing parcels of water which are in the air, must needs make the water run out at that end of the syphon, where the overweight of water is.

The Attraction, whose cause next to this is most manifest, is that which is made by the force of heat or fire: for, we see that * 1.183 fire ever draws air to it; so notably, that, if in a close room there be a good fire, a man that stands at the door or window (especially without) shall hear such a noise, that he will think there is a great wind within the chamber. The reason of this attraction is, that fire, rarifying the air next it, and with∣all spending it self perpetually, causes the air, and his own body mingled together to fly up through the chimney, or by some other passage: Whence it follows of necessity, that the next body must succeed into the place of the body that is flown away. The next body generally is air, whose mobility and flu∣idity, beyond all other bodies, makes it of all others the fittest to be drawn, and the more of it is drawn, the more must needs follow. Now, if there be floating in this air any other atoms, subject to the current which the air takes; they must also come with it to the fire, and by it be rarified and exported out of that little orb.

Hence it is, that men (with very good reason) hold that fire airs a chamber, as we term it; that is, purifies it: both be∣cause it purifies it, as wind doth, by drawing a current of air in∣to it that sweeps through it; or by making it purifie it self by motion, as a stream of water doth by running; as also, because those vapours which approach the fire are burned & dissolv'd. So that the air, being noisome and unwholesome, by reason of its grossness, (proceeding from its standing unmoved, like a stagnation of dead water, in a marish place) the fire takes away that cause of annoyance.

By this very rule we learn, that other hot things, which parti∣cipate the nature of fire, must likewise (in other respects) have a * 1.184 resemblance in this quality. And accordingly we see, that hot loaves in a Bakers shop, newly drawn out of the Oven, are accoun∣ted to draw to them any infection which is in the air. The like we say of onyons, and other strong breathing substances; which by their smel shew much heat in them. In like manner 'tis con∣ceiv'd, that Pigeons and Rabbets and Cats easily take infection; by reason of their extraordinary warmth which they have in themselvs.

And this is confirm'd by the practise of Physitians, who use to lay warm Pigeons newly killed to the feet, wrists, or heads of sick persons, and young Puppies to their stomacks, and somtimes cer∣tain hot gums to their navels; to draw out such vapours or hu∣mours as infest the body: for the same reason, they hang amulets of arsenick, sublimate, dryed Toads, or Spiders, about their pati∣ents necks; to draw to them venimous qualities from their bo∣die. Hence also it is that, if a man be strucken by a Viper or a Scorpion, they use to break the body of the beast it self that stung him (if they can get it) upon the wound: but, if the beast be crawl'd out of their finding, they do the like by some other veni∣mous creature; as I have seen a bruised Toad laid to the biting of a Viper. And they manifestly perceive the apply'd body to swel with the Poyson suck'd out from the wound, & the patient to be reliev'd & have less poyson; in the same manner as, by cup∣ping-glasses, the poyson is likewise drawn out from the wound: so that you may see, the reason of both is the very same; or at least very like one another. Only, we are to note, that the pro∣per body of the beast, out of which the venome was driven into the wound, is more efficacious than any other to suck it out.

And the like is to be observ'd in all other kinds, that such va∣pours, as are to be drawn, come better and incorporate faster in bodies of like nature, then in those which have only the common conditions of heat and dryness, the one of which serves to at∣tract, the other to fasten and incorporate into itself the moisture which the first draws to it. So we see that water soaks into a dry body, whence it was extracted, almost inseparably, and is hidden in it; as, when it rains first after hot weather, the ground is pre∣sently dried after the shower. Likewise we see that, in most ce∣ments,

you must mingle a dust of the nature of the things which are to be cemented, if you will have them bind strongly.

Out of this discourse, we may yield a reason for those Magical * 1.185 operations, which some attribute to the Devils assistance; perad∣venture because mans wickedness hath bin more ingenious then his good will, and so has found more means to hurt then to help; nay, when he hath arrived some way to help, those very helps have undergone the same calumny, because of the likeness which their operations have to the others. Without doubt very unjustly; if there be truth in the effects: For, where have we any such good suggestions of the enemy of mankind proposed to us, that we may with reason believe he would duly, settledly, and constantly concur to the help and service of all those he so much hates; as he must needs do if he be the Author of such ef∣fects? Or, is it not a wrong to Almighty God, and to his careful instruments; rather to impute to the Devil the aids, which to some may seem supernatural, then to them of whom we may justly believe and expect such good Offices and assistances? I mean, those operations, both good and bad, which ordinarily are called Magnetical; though peradventure wrongfully, as not having that property whcih denominates the loadstone.

One thing I may assure, that, if the reports be true, they have the perfect imitation of nature in them. As for example; that the Weapons-Salve, or the Sympathetick-Powder, requires, in the using it, to be conserved in an equal moderate temper; and that the weapon which made the wound, or the cloth upon which the blood remains that issued from it, be orderly and fre∣quently dressed: or else the wounded person will not be cured. Likewise, the steam or spirits, which at the giving of the wound enter'd into the pores of the weapon, must not be driven out of it, (which will be done by fire: and so, when it is heated by holding over coals, you may see a moisture sweat out of the blade at the opposite side to the fire, as far as it entred into the wounded persons body; which being once all sweated out, you shall see no more the like steam upon the sword), neither must the blood be washed out of the bloudy cloth: for, in these cases, the powder, or salve, will work nothing. Likewise, if there be any excess either of heat or cold in keeping the medicated wea∣pon or cloth; the patient feels that, as he would do, if the like

excess where in any remedy that were applyed to the wound it self. Likewise, if the medicated weapon or bloudy cloth, be kept too close, no effect follows. Likewise, the natures of the things used in these cures are, of themselves, soveraign for healing the like griefs; though peradventure too violent, if they were ap∣ply'd in body, without much attenuation.

And truly, if we will deny all effects of this kind, we must in a manner renounce all humane faith: men of all sorts and qua∣lities (and many of them such, in my own knowledge, as I can∣not question their prudence in observing, or their sincerity in relating) having very frequently made experience of such me∣dicines; and all affirming after one fashion to have found the same effects. Adde to these the multitude of other like effects, appearing, or conceited to appear, in other things. In some Coun∣tries 'tis a familiar disease with Kine, to have a swelling in the soles of their feet: and the ordinary cure is, to cut a turf upon which they have troden with their sore foot, and to hang it upon a hedge; & as that dries away, so will their sore amend. In other parts they observe, that if milk, newly come from the cow, in the boyling run over into the fire, and that this happen often and near together to the same cows milk; that cow will have her udder sore inflamed: and the prevention is, to cast salt imme∣diately into the fire upon the milk. The herb Persicaria, if it be well rub'd upon Warts, and then be laid in some fit place to putrifie, causes the Warts to wear away, as it rots: some say the like of fresh Beef. Many examples also there are of hurting living creatures, by the like means; which I set not down, for fear of doing more harm, by the evil inclination of some per∣sons into whose hands they may fall, then profit, by their know∣ing them to whom I intend this work.

But, to make these operations of nature not incredible: let us remember how we have determin'd; that every body what∣ever yields some steam, or vents a kind of vapour from it self; and consider, how they must needs do so most of all, that are hot and moist, as bloud and milk, and all wounds and sores generally are. We see that the foot of a Hare or Bear leaves such an impression where the beast has passed, as a dog can dis∣cern it a long time after: and a Fox breaths out so strong a va∣pour, that the hunters themselvs can wind it a great way off,

and a good while after he is parted from the place. Now, joyn∣ing this to the experiences we have already allow'd of, concern∣ing the attraction of heat; we may conclude that, if any of these vapours light upon a solid warm body, which has the na∣ture of a source to them, they will naturally congregate and incorporate there: and, if those vapours be joyn'd with any me∣dicative quality or body, they will apply that medicament bet∣ter then any Chirurgeon can. Then, if the steam of bloud bloud and spirits carry with it, from the weapon or cloth, the balsamike qualities of the salve or powder; and with them settle upon the wound: what can follow but a bettering in it? Likewise, if the steam of the corruption that is upon the clod, carry the drying quality of the wind, which sweeps over it when it hangs high in the air, to the sore part of the cows foot; why is it not possible that it should dry the corruption there, as well as it dryes it upon the hedge; And, if the steam of burned milk can hurt, by carrying fire to the dug: why should not salt cast upon it be a preservative against it? Or rather, why should not salt hinder the fire from being carried thither? Since the nature of salt always hinders and suppresses the activity of fire: as we see by experience, when we throw salt into the fire below, to hinder the flaming of soot in the top of a chimney; which presently ceases, when new fire from beneath doth not continue it. And thus we might proceed, in sundry other ef∣fects, to declare the reason and possibility, were we certain of the truth of them: therfore we remit this whole question to the authority of the testimonies.

CHAP. XIX. Of three other motions belonging to particular bodies, Filtration, Restitution, and Electrical attraction.

AFter these, let us cast our eye upon another motion, very fa∣miliar * 1.186 among Alchymists; which they call Filtration. It is effected by putting one end of a tongue or label of Flannen, or Cotten, or Flax, into a vessel of water; and letting the other end hang over the brim of it: And it will, by little and little, draw all the water out of that vessel (so that the end which hangs q••t be lower then the superficies of the water); and make it all come over into any lower vessel you will reserve it in.

The end of this operation is, when any water is mingled with gross and muddy parts (not dissolv'd in the water); to separate the pure & light ones from the impure. By which we are taught, that the lighter parts of the water are those which most easily catch. And, if we will examine in particular, how 'tis likely this business passes; we may conceive that the body or linguet, by which the water ascends, being a dry one, some lighter parts of the water, whose chance it is to be near the climbing body of Flax, begin to stick fast to it: and then, they require nothing near so great force nor so much pressing, to make them climb up along the flax, as they would do to make them mount in the pure air, As you may see, if you hold a stick in run∣ning water, shelving against the stream: the water will run up along the stick, much higher then it could be forced up in the open air without any support; though the agent were much stronger then the current of the stream. And a ball will, on a rebound, run much higher upon a shelving board, then it would if nothing touch'd it. And I have been told that, if an egsshell fill'd with dew be set at the foot of a hollow stick; the Sun will draw it to the top of the shelving stick; wheras without a prop, it will not stir it.

With much more reason then, we may conceive that water, finding as it were little steps in the Cotton, to facilitate its jour∣ny upwards, must ascend more easily then those other things do; so as it once receive any impulse to drive it upwards. For, the gravity, both of that water which is upon the Cotton, as also, of so many of the confining parts of water as can reach the Cot∣ton, is exceedingly allay'd; either by sticking to the Cotton, and so weighing in one bulk with that dry body, or else, by not tend∣ing down straight to the Center, but resting as it were upon a steep plain (according to what we said of the arm of a Syphon that hangs very sloping out of the water, and therfore draws not after it a less proportion of water in the other arm that is more in a direct line to the Center): by which means the wa∣ter, as soon as it begins to climb, comes to stand in a kind of cone; neither breaking from the water below, (its bulk being big * 1.187 enough to reach to it) nor yet falling down to it.

But our chief labour must be, to finde a cause that may make the water begin to ascend. To which purpose, consider how water

of its own nature, compresses it self together, to exclude any other body lighter then it is. Now, in respect of the whole mass of the water, those parts which stick to the cotton are to be ac∣ounted muchlighter then water: not, because in their own nature they are so; but for the circumstances which accompany and give them a greater disposition to receive a motion upwards, then much lighter bodies, whiles they are destitute of such helps. Wherfore as, the bulk of water weighing and striving down∣wards, it follows that, if there were any air mingled with it, it would, to possess a lesser place, drive out the aire: so here in this case, the water at the foot of the ladder of cotton, ready to climb with a very small impulse may be, after some sort, com∣pared (in respect of the water) to air, by reason of the lightness of it; and, consequently, is forced up by the compressing of the rest of water round about it. Which no faster gets up, but other parts at the foot of the ladder follow the first, and drive them still upwards along the tow; and new ones drive the second, and others the third, and so forth: so that with ease they climb up to the top of the filter, still driving one another forwards: as you may do a fine towel through a musket barrel, which, though it be too limber to be thrust straight through, yet, craming still new parts into it, at length you will drive the first quite through.

And thus, when these parts of water are got up to the top of the vessel on which the filter hangs, and over it on the other side; by sticking still to the tow, and by their natural gravity, a∣gainst which nothing presses on this side the label: they fall down again by little and little, and by drops break again into water in the vessel set to receive them.

But now if you ask, why it will not drop, unless the end of the label that hangs be lower then the water? I conceive it * 1.188 is, because the water, which is all along upon the flannen, is one continued body hanging together, as it were a thrid of wire; and is subject to like accidents as such a continued body is. Now, suppose you lay wire upon the edge of the basin, which the filter rests on; and so make that edge the Centre to ballance it upon: if the end that is outermost be heaviest, it will weigh down the other; otherwise, not. So fares it with this thrid of water: if the end of it that hangs out of the pot

be longer, and consequently heavier, then that which rises; it must needs raise the other upwards, and fall it self downwards. Now, the raising of the other implies lifting more water from the Cistern; and the sliding of it self further downwards is the cause of its converting into drops. So that the water in the ci∣stern serves like the flax upon a distaff; and is spun into a thrid of water, still as it comes to the flannen, by the drawing it up, occasion'd by the overweight of the thrid on the other side of the center.

Which to express better by a similitude in a solid body: I re∣member I have oftentimes seen, in a Mercers shop, a great heap of massy gold lace lie upon their stall; and a little way above it, a round smooth pin of wood, over which they use to have their lace when they wind it into bottoms. Now, over this pin, I have put one end of the lace; &, as long as it hung no lower then the board upon which the rest of the lace did lie, it stird'd not: for as the weight of the loose end carried it one way, so the weight of the otherside, where the whole was, drew it the otherway; & in this manner kept it in equalibrity. But, as soon as I drew on the hanging end to the heavier then the climbing side, (for, no more weights then is in the air, that which lies upon the board having another center); then it began to roule to the ground: and still drew up new parts of that which lay upon the board, till all was tumbled down upon the floor. In the same manner it hap'nes to the water; in which, the thrid of it upon the filter is to be compared fitly to that part of the lace which hung upon the pin, and the whole quantity in the cistern is like the bulk of lace upon the Shopboard: for, as fast as the filter draws it up, 'tis converted into a thrid like that which is alrea∣dy upon the filter; in like manner as the wheel converts the flax into yarn, as fast as it draws it out from the distaff.

Our next consideration will very aptly fall upon the motion * 1.189 of those things which, being bent, leap with violence to their former figure: wheras others return but a little; and others stand in that ply, wherin the bending hath set them. For finding the reason of which effects, our first reflection may be, to note that a Superficies, which is more long then broad, con∣tains a less floor, then that whose sides are equal, or nearer be∣ing equal: and that, of those surfaces whose lines and angles are

all equal, that which hath most sides and angles contains still the greater floor. Whence it is that Mathematicians conclude a circle to be the most capacious of all figures: and what they say of lines in respect of a superficies, the same, with proportion, they say of surfaces, in respect of the body contained. And ac∣cordingly, we see by consequence, that, in the making a bag of a long napkin; if the napkin be sew'd together longwise, it holds a great deal less, then if it be sewd together broadwise.

By this we see plainly, that if any body, in a thick and short figure, be forced into a thinner (which, by becoming thinner, must likewise become either longer or broader; for what it lo∣ses one way, it must get another); then that superficies must needs be stretched: which, in our case, is a Physical outside, or mate∣rial part of a solid body; not a Mathematical consideration of an indivisible Entity. We see also that this change of figures happens in the bending of all those bodies, wherof we are now enqui∣ring the reason, why some of them restore themselves to their original figures, and others stand as they are bent.

Then, to begin with the latter sort: we find that they are of a moist nature; as, among metalls, lead and tin, and, among other bodies, those ••which we account soft. And we may determine that this effect proceeds, partly from the humidity of the body that stands bent; and partly from a driness peculiar to it, that comprehends and fixes the humidity of it. For, by the first, they are render'd capable of being driven into any figure, which na∣ture or art desires: and, by the second, they are preserv'd from having their gravity put them out of what figure they have once receiv'd.

But, because these two conditions are common to all solid bo∣dies; we may conclude that, if no other circumstance concur'd, the effect arising out of them would likewise be common to all such: and therfore, where we find it otherwise, we must seek fur∣ther for a cause of that transgression. As for example, if you bend the bodies of young trees, or the branches of others; they will return to their due figure. 'Tis true, they will somtimes lean to∣wards that way they have been bent: as may be seen even in great trees after violent tempests, and generally the heads of trees, & the ears of corn, and the grown hedg rows will all bend one way in some countries, where some one wind has a

main predominance and reigns most continually; as near the Seashore upon the western coast of England (where the South-West wind blows constantly the greatest part of the year) may be observed: but this effect, proceeding from a particular and ex∣traordinary cause, concerns not our matter in hand.

We are to examine the reason of the motion of Restitution, which we generally see in young trees, and branches of others; as we said before. In such we see that the earthy part which makes them stiff (or rather stark) abounds more, then in the o∣thers that stand as they were bent; at least in proportion to their natures: but I conceive this is not the cause of the effect we en∣quire about; but that 'tis a subtile spirit which hath a great pro∣portion of fire in it. For as, in rarefaction, we found that fire, which was either within or without the body to be rarified, did cause the rarefaction; either by entring into it, or by working within it: so, seeing here the question is, for a body to go out of a lesser superficies, into a greater (which is the progress of rare∣faction, and hapen's in the motion of restitution); the work must needs be done by the force of heat. And because this effect pro∣ceeds, evidently, out of the nature of the thing in which it is wrought; and not from any outward cause: we may conclude, it has its origine from a heat within the thing it self; or else that was in it, and may be press'd to the outward parts of it, and would sink into it again.

As for example, when a young tree is bended, both every mans conceit is, and the nature of the thing makes us believe, that the force, which brings the tree back again to its figure, comes from the inner side that is bent; which is compress'd to∣gether, as being shrunk into a circular figure from a straight one: for, when solid bodies that were plain on both sides are bent, so as on each side to make a portion of a Circle; the convex super∣ficies will be longer then it was before when it was plain, but the concave will be shorter. And therfore we may conceive that the spirits, which are in the contracted part, (being there squeez'd in∣to less room, then their nature well brooks) work themselvs into a greater space; or else, that the spirits, which are crush'd out of the convex side by the extension of it, remain be∣sieging it and strive to get in again, (in such manner as we have declared when we spoke of attraction, wherin we shew'd

how the emited spirits of any body will move to their own source, and settle again in it, if they be within a convenient com∣pass;) and accordingly bring back the extended parts to their former situation: or rather, that both these causes, in their kinds, concur to drive the tree into its natural figure.

But, as we see, when a stick is broken, 'tis very hard to re∣place all the splinters, every one in its proper situation; so it must * 1.190 of necessity fall out in this bending, that certain insensible parts, both inward and outward, are therby displaced, and can hardly be perfectly rejoynted. Whence it follows that, as you see the splinters of a half broken stick, meeting with one another, hold the stick somwhat crooked; so these invisible parts do the like, in such bodies as, after bending, stand a little that way: but, because they are very little ones, the tree or branch, that has been never so much bended, may (so nothing be broken in it) be set strait again by pains, without any notable detriment of its strength. And thus you see the reason of some bodies returning in part to their natural figures after the force leaves them that bent them.

Out of which you may proceed to those bodies that restore themselvs entirely: whereof steel is the most eminent. And, of it, we know, that there is a fiery spirit in it, which may be extract∣ed out of it; not only by the long operations of calcining, dige∣sting, and distilling it; but even by gross heating, and then ex∣tinguishing it in wine and other convenient Liquors, as Physici∣ans use to do. Which is also confirm'd, by the burning of steel∣dust in the flame of a candle, before it has been thus wrought up∣on; which after-wards it will not do: wherby we are taught that, originally, there are store of spirits in steel, till they are sucked out. Being then assured that in steel there is such abundance of spirits, and knowing that it is the nature of spirits to give a quick motion, and seeing that duller spirits in trees make this motion of Restitution; we need seek no further, what it is that doth it in steel, or in any other things that have the like nature: which, through the multitude of spirits that abound in them, (especially steel) returns back with so strong a jerk, that their whole body will tremble a great while after, by the force of its own motion.

By what is said, the nature of those bodies which shrink and * 1.191 stretch may easily be understood: for, they are generally com∣posed

of stringy parts, to which if humidity happen to arrive, they grow therby thicker and shorter. As we see that drops of water, getting into a new rope of a well, or into a new cable, will swell it much thicker; and by consequence, make it shorter. Galileus notes such wetting to be of so great efficacy, that it will shrink a new cable, and shorten it notably; notwithstanding the violence of a tempest, & the weight and jerks of a loaden ship, strain it what is possible for them to stretch it. Of this nature leather seems to be, and parchment, and divers other things: which, if they be proportionably moistned (and no exteriour force apply'd to extend them), will shrink up; but if they be overweted, they will become flaccide. Again, if they be sud∣denly dryed, they'l shrivel up; but, if they be fairly dried after moderate weting, they will extend themselvs again to their first length.

The way having been open'd (by what we have discoursed, before we came to the motion of Restitution) towards the disco∣very * 1.192 of the manner how heavy bodies may be forced upward, contrary to their natural motion; by very smal means in out∣ward appearance: let us now examine (upon the same grounds), if like motions to this of water, may not be done in some other bo∣dies, in a subtiler manner. In which more or less needs not trou∣ble us; since we know, that neither quantit•• ••or the operations of it consist in an indivisible, or are limited or determin'd by pe∣riods they may not pass. 'Tis enough for us to find a ground for the possibility of the operation: and then the perfecting and re∣ducing of it to such a height, as at first might seem impossible & in∣credible, we may leave to the Oeconomy of wise nature. He that learns to read, write, or play on the Lute, is, in the beginning, rea∣dy to lose heart at every step; when he considers with what la∣bour, difficulty, and slowness he joyns the letters, spells syllables, forms characters, fits and breaks his fingers (as though they were upon the rack), to stop the right frets, and touch the right strings: and yet you see how strange a dexterity is gain'd in all these by industry and practise; and readiness beyond what we could imagine possible, if we saw not dayly the effects.

If then we can but arrive to decipher the first characters of the hidden Alphabet we are now taking in hand, and can but spel∣lingly

read the first syllables of it, we need not doubt, but that the wise Author of nature, in the masterpiece of the creature (which was to express the excellency of the workman), would with excellent cunning & art dispose all circumstances so aptly, as to speak readily a compleat language rising from those Ele∣ments; and that should have as large an extent in practise and expression, beyond those first principles, which we like children only lisp out, as the vast discourses of wisest & most learned men are beyond the spellings of infants: and yet those discourses spring from the same root, as the other spellings do, and are but a raising of them to a greater height; as the admired musick of the best player on a Lute or Harp that ever was is derived from the harsh twangs of course Bowstrings, which are composed to∣gether and refined, till at length they arrive to that wonderful perfection. And so, without scruple, we may, in the business we are next falling upon, conclude, that the admirable and almost mi∣raculous effects we see are but the elevating-to-a-wonderful-height those very actions and motions, which we shall produce as causes and principles of them.

Let us then suppose a solid hard body, of an unctuous nature; whose parts are so subtile and fiery, that, with a little agitation, * 1.193 they are much rarified and breath out in steams, (though they be too subtile for our eyes to discern), like the steam that issues from sweating men or horses, or that which flyes from a candle when 'tis put out: but that these steams, as soon as they come into the cold air, are by that cold suddenly condens'd again, and, by being condens'd, shorten themselvs, and by little and little re∣tire, till they settle themselvs upon the body from whence they sprung; in such manner as you may observe the little tender horns of Snails use to shrink back, if any thing touch them, till they settle in little lumps upon their heads If, I say, these strings of bituminous vapours should, in their way outwards, meet with any light and spungy body, they would pierce into it, and settle in it: and, if it were of a competent bigness for them to wield, they would carry it with them which way soever they go; so that, if they shrink back again to the fountain from whence they came, they must needs carry back with them the light spungy body they have fixed their darts in.

Consider, then, that, how much heat rarifies, so much cold

condenses; and therfore such parts as by agitation were spun out into a subtile thrid of an inch long (for example) as they cool, grow bigger and bigger, and consequently shorter and shorter: till at length, they gather themselvs back into their main body, and there they settle again in cold bitumen as they were at first; and the light body they stick to is drawn back with them, and consequently sticks to the superficies of the bitumen. As if some∣thing were tyed at one end of a lu••estring extended to its utmost capacity, and the other end were fastned to some pin; as the string shrinks up, so that which is tyed at it must needs move nearer and nearer the pin: which artifice of nature jugglers imitate, when, by means of an unseen, hair, they draw light bo∣dies to them. Now, if all this operation be done, without your seeing the little thrids which cause it; the matter appears won∣derful and strange: But, when you consider this progress that we have set down, you will judge it possible.

And this seems to be the case of those bodies which we call Electrical; as yellow Amber, Jet, and the like: all which are of a bituminous unctuous nature; as appears by their easie combu∣stibility and smel, when they are burned. And if some do not so apparently shew this unctuous nature, it is because either they are too hard, or else they have a high degre of aqueous humidi∣ty joyn'd with their unctuosity: and in them the operation will be duller in that proportion. For, as we see that unctuous substan∣ces are more odoriferous then others, and send their streams further off and more efficaciously; so we cannot doubt but such bodies as consist in a moist nature accordingly send forth their emanations in a feebler proportion. Yet, that proportion will not be so feeble, but they may have an Electrical effect, as well as the more efficacious Electrical bodies: which may be perceptible, if exact experience be made by an instrument like the Marri∣ners needle; as our learned Countryman Dr. Gilbert teaches.

But, that, in those eminent agents, the spirits, wherby they at∣tract, are unctuous, is plain, because the fire consumes them and so, if the agents be over heated, they cannot work: but mode∣rate heat, even of fire, encreases their operation. Again, they are clog'd by mysty air, or wettine: and likewise, are pierc'd through and cut asunder by spirit of wine, or aquae ardentes; but oyl doth not hurt them. Likewise, they yield more spirits in

the Sun then in the shade; and they continue longer, when the air is cleard by North or Eastern winds. They require to be polish'd; either because the rubbing, which polish'd them, takes off from their surfaces the former emanations, which re∣turning back stick upon them, and so hinder the passage of those that are within: or else, because their outsides may be foul; or lastly, because the ports may be dilated by that smoo∣thing. Now, that hardness and solidity is required, argues that these spirits must be quick ones; that they may return smartly, and not be lost through their languishing in the air. Likewise, that all bodies, which are not either exceeding rare, or else set on fire, may be drawn by these unctuous thrids, concludes that the quality by which they do it is a common one, that hath no particular contrarieties: such an one as we see in grease or in pitch, to stick to any thing; from which in like manner nothing is exempted, but fire and air. And lastly, that they work most ef∣ficaciously when they are heated by rubbing, rather then by fire, shews that their spirits are excitated by motion, and therby made to fly abroad; in such manner as we see in Pomanders and other perfumes, which must be heated if you will have them communicate their scent. And a like effect as in them, agi∣tation doth in Jet, yellow Amber, and such other Electrical bo∣dies; for, if, upon rubbing them, you put them presently to your nose, you wil discern a strong bituminous smel in them. All which circumstances shew, that this electrical virtue consists in a certain degree of rarity or density of the bodies unctuous emanations:

Now, if these refined and viscuous thrids of Jet or Amber, in their streaming abroad, meet with a piece of straw, or hay, or dried leaf, or some such light and spungy body; 'tis no marvel if they glew themselvs to it like birdlime: and that in their shrink∣ing back (by being condens'd again and repuls'd, through the coldness of the air) they carry it along with them to their entire body. Which they that only see the effect, and cannot penetrate into a possibility of a natural cause therof, are much troubled withal. * 1.194

And this seems to me to bear a fairer semblance of truth, then what Cabeus delivers for the cause of Electrical attracti∣ons: whose speculation herein, though I cannot allow for solid, yet I must for ingenious. (And certainly even errours are to be

commended, when they are witty ones; and proceed from a cast∣ing-further-about then the beaten Tract of verbal learning, or rather terms, which explicate not the nature of the thing in question). He sayes that the coming of straws and such other light bodies to Amber, Jet, and the like, proceeds from a wind, raised by the forcible breaking out of subtile emanations from the Electrical bodies into the air which brings those light bo∣dies along with it to the Electrical ones.

But this discourse cannot hold. For, First, 'tis not the nature of unctuous emanation (generally speaking) to cause smart mo∣tions singly of themselvs. Secondly, although they should raise a wind, I do not comprehend how this wind should drive bodies directly back to the source that raised it; but rather any other way; and so, consequently, should drive the light bodies, it meets with in its way, rather from, then towards the Electrical body. Thirdly, if there should be such a wind raised, and it should bring light bodies to the Electrical ones; yet it could not make them stick therto; which we see they do, turn them which way you will; as though they were glew'd together.

Neither do his experiences convince any thing. For, what he saies, that the light bodies are somtimes brought to the Electri∣cal body with such a violence, that they rebound back from it, and then return again to it, makes rather against him: for, if wind were the cause of their motion, they would not return a∣gain, after they had leaped back from the Electrical body; no more then we can imagine that the wind it self doth.

The like is of his other experience; when he observ'd that, some little grains of Saw-dust hanging at an Electrical body, the furthermost of them not only fell off, but seem'd to be dri∣ven away forcibly: for, they did not fall directly down, but side∣wayes; and besides, flew away with a violence and smartness, that argued some strong impulse. The reason wherof might be, that, new emanations might smite them; which, not sticking and fast'ning upon them, wherby to draw them nearer, must needs push them further: or it might be that the emanations, to which they were glew'd, shrinking back to their main body, the la∣ter grains were shoulder'd off by others that already besieg'd the Superficies; and then, the emanations retiring swiftly, the grains must break off with a force: or else we may conceive it was the

force of the air that bore them up a little, which made an ap∣pearance of their being driven away; as we see feathers and o∣ther light things descend not straight down.

CHAP. XX. Of the Loadstones generation; and its particular motions.

THere is yet remaining the great Mystery of the Loadstone * 1.195 to discourse of: Which all Authors, both ancient and modern, have agreed upon as an undeniable example and evi∣dence of the shortness of mans reach in comprehending, and of the impossibility of his reason in penetrating into and expli∣cating such secrets, as nature hath a mind to hide from us. Wherfore our Reader (I am sure) will not, in this subject, expect clear satisfaction or plain demonstrations, at our hands: but will judg we have fairly acquitted our selves, if what we say be any whit plausible.

Therefore, to use our best indeavours to content him; let us reflect upon the disposition of parts of this habitable Globe, wherof we are Tenants for life: And we shall find that the Sun, by his constant course under the Zodiack, heats a great part of it unmeasurably more then he doth the rest. And consequently, that this Zodiack, being in the mid'st between two (as it were) ends, which we call the Poles; these Poles must necessarily be extremely cold, in respect of the Torrid Zone: for, so we call that part of the earth which lies under the Zodiack.

Now, looking into the consequence of this, we find that the Sun, or the Suns heat which reflects from the earth in the Torrid Zone, must rarifie the air extremely; and, according to the nature of all heat and fire, must needs carry away from thence many parts of the air and earth sticking to that heat, in such sort as we have formerly declared.

Whence it follows, that other air must necessarily come from the Regions towards both the Poles, to supply what is car∣ried away from the middle; as is the course in other fires, and as we have explicated above * 1.196. Especially considering that the air, which comes from the Polewards, is heavier then the air of the Torrid Zone, and therfore, must naturally press to be still nearer the earth; and so, as it were shoulders on the air

of the Torrid Zone towards the circumference, by rolling into its place: and this, in great quantities; and consequently, the polar air must draw a great train after it.

Which, if we consider the great extent of the Torrid Zone, we shall easily perswade our selvs, must reach on each side, to the very Pole. For, taking from Archimedes, that the Spherical Superficies of a portion of a Sphere is, to the Superficies of the whole Sphere, according as the parts of the axis of that Sphere, comprised within the said portion, is to the whole axis: and considering that (in our case) the part of the axis comprised with∣in the Torrid Zone is, to the whole axis of the earth, in about the proportion of 4. to 10: it must of necessity follow, that a fire or great heat, reigning in so vast an extent, will draw air very pow∣erfully from the rest of the world.

Neither let any man apprehend, that this course, of the Sun's elevating so great quantities of Atoms in the Torrid Zone, should hinder the course of gravity there. (For, first, the medium is much rarer in th•• Torrid Zone, then in other parts of the earth; and therfore the force of the descending Atoms needs not be so great there as in other places, to make bodies descend there as fast as they do elsewhere. Secondly, there being a perpetu∣al supply of fresh air from the Polar parts, streaming continu∣ally into the Torrid Zone; it must of necessity happen that, in the air, there come Atoms to the Torrid Zone, of that grossness that they cannot suddenly be so much rarified as the subtiler parts of air that are there: and therfore, the more those sub∣tiler parts are rarified, and therby happen to be carried up; the stronger and the thicker the heavier Atoms must descend. And thus this concourse of air from the Polar parts maintains gra∣vity under the Zodiack; where otherwise all would be turned into fire, and so have no gravity.

Now, who considers the two Hemispheres, which, by the * 1.197 Equator are divided, will find that they are not altogether of equal complexions; but that our Hemisphere, in which the Northpole is comprised, is much dryer then the other, by rea∣son of the greater continent of land in this, and the vast tract of Sea in the other; and therfore, the supply which comes from the divers Hemispheres must needs be of different natures; that which comes from towards the Southpole, being compared to

that which comes from towards the North, as the more wet to the more dry. Yet, of how different complexions soever they be, you see they are the emanations of one and the same body. Not unlike to what nature hath instituted in the rank of Animals: among whom the Male and Female are so distinguish'd by heat and cold, moisture and drought, that nevertheless all belongs but to one nature; and that, in degrees, though manifestly different, yet so near together, that the body of one is, in a manner, the same thing, as the body of the other. Even so, the complexions of the two Hemispheres are in such sort different in the same qualities, that nevertheless they are of the same na∣ture; and are unequal parts of the same body which we call the Earth. Now, Alchimists assure us, that, if two extractions of one body meet together, they will incorporate one with the other; especially, if there be some little difference in the complexion of the extractions.

Whence it follows, that these, two streams of air, making up one continuate floud of various currents, ••om one end of the * 1.198 world to the other; each stream that come to the Equator from its own Pole by the extraction of the Sun, and that is still sup∣ply'd with new matter flowing from its own Pole to the Equa∣tor, before the Sun can sufficiently rarifie and lift up the A∣tomes that came first Perpendicularly under its beams, (as it uses to happen in the effects of Physical causes, which cannot be rigorously ajusted, but must have some latitude; in which nature inclines ever rather to abundance then to defect), will pass even to the other pole, by the conduct of his fellow, in case he be by some occasion driven back homewards.

For, as we see in a Bowl or Pail full of water, or rather in a Pipe, through which the water runs along; if there be a little hole at the bottome or side of it, the water will wriggle and change its course to creep out at that Pipe: especially if there be a little spiggot, or quill at the outside of the hole, that by the narrow length of it helps in some sort (as it were) to suck it. So, if any of the files of the army or floud of Atoms, sucked from one of the Poles to the Equator, do there find any gaps, or chinks, or lanes of retiring files in the front of the other poles battalia of atomes; they will press in there, (in such mannner as we have above declared that water doth by the help of a label

of cotten; and as is exemplyfied in all the attractions of venime by venimous bodies, wherof we have given many examples above): and they will go along with them the course they go. For as, when a thick short gilded ingot of silver is drawn out in∣to a long subtile wyre; the wyre, continuing still perfectly guilded all over, manifestly shews that the outside and the in∣side of the ingot strangely meet together, and intermix in the drawing out: so this little stream, which (like an Eddy current) runs back from the Equator towards its own Pole, will conti∣nue to the end still tincted with the mixture of the other Poles atoms, it was incorporated with at his coming to the Equator.

Now, that some little rivolets of air and atoms should run back to their own Pole, contrary to the course of their main stream, will be easy enough to conceive; if we but consider that, at certain times of the year, winds blow more violently and strongly from some determinate part or Rombe of the world, then they do at other times, and from other parts. As for example; our East India Marriners tell us of the famous Monsones they find in those parts: whch are strong winds that reign constantly six moneths of the year from one polewards, and the other six moneths from the other pole; & beginning precise∣ly about the Suns entring into such a sign or degree of the Zodiac, and continue til about its entrance into the opposite degree. And, in our parts of the world, certain smart Easterly or Northeaster∣ly winds reign about the end of March and beginning of April; when it seems that some snows are melted by the spring heats of the Sun. And other winds have their courses in other seasons, upon other causes. All which evidently convince, that the course of the air and vapours, from the poles to the Equator, cannot be so regular and uniform, but that many impediments and cros∣ses light in the way, to make breaches in it; and therby to force it in some places to an opposite course. In such sort as we see happens in eddy waters, and in the course of a tide; wherin the stream, rūning swiftly in the middle, beats the edges of the water to the shore, and therby makes it run back at the shore. And hence we may conclude that, although the main course of air & atoms (for example, from North to South, in our Hemisphere) can never fail of going on towards the Equator, constantly at the

same rate, in gross; nevertheless, in several particular little parts of it, (and especially at the edges of those streams that are driven on faster then the rest, by an extraordinary and accidental vio∣lent cause) it is variously interrupted, and somtimes intirely stop'd, and other times even driven back to the Northwards.

And, if peradventure any man should think that this will not fall out; because each stream seems to be always coming from his one Pole to the Equator, and therfore will oppose and drive back any bodies that with less force should strive to swim against it; or, if they stick to them, will carry them back to the Equator. We answer, that we must not conceive the whole air in body doth every where equally incroach from the Polewards upon the Torrid Zone; but, as it were, in certain brooks or rivu∣lets, according as the contingency of all causes put together makes it fall out.

Now then, out of what we have said, it will follow, that; since all the air in this our Hemisphere is, as it were, strew'd over and sow'd with abundance of Northern atoms; and that some brooks of them are in station, others in a motion of retrogradation back to their own North Poles: the Southern atoms (which, co∣ming upon them at the Equator, do not only press in among them, wherever they can find admittance, but also go on for∣wards to the North Poles in several files by themselvs; being driven that way by the same accidental causes, which make the others retire back), seizing in their way upon the northern ones, in such manner as we described in filtration, and therby creep∣ing along by them wherever they find them standing stil, and going along with them wherever they find them going back, must of necessity find passage in great quantites towards and even to the North Pole; though some parts of them will ever and anon be check'd in this their journey by the main current pre∣vailing over some accidental one, and so be carried back again to the Equator, whose line they had crossed.

And this affect cannot choose but be more or less, according to the seasons of the year. For, when the Sun is in the Tropick of Capricorn, the southern atoms will flow in much more abun∣dance, and with far greater speed, into the Torrid Zone, then the northern atoms can; by reason of the Suns approximation to the South, and his distance from the North Pole: since he

works faintest, where he is furthest off; and therfore from the North no more emanations or Atoms will be drawn, but such as are most subtilised and duly prepared for that course. And, since only these selected bands do now march towards the Equator; their files must needs be thinner, then when the Suns being in the Equator or Tropick of Cancer wakens and musters up all their forces. And consequently, the quiet parts of air between their files (in which like Atoms are also scat∣ter'd) are the greater; wherby the advenient Southern A∣toms have the larger filter to climb up by. And the like hap∣pens in the other Hemisphere, when the Sun is in the Tropick of Cancer; as who will bestow the pains to compare them, will presently see. * 1.199

Now then, let us consider what these two streams thus incor∣porated, must of necessity do in the surface or upper parts of the Earth. First, 'tis evident they must needs penetrate a pretty depth into the Earth: for so freezing perswades us; and much more, the subtile penetration of divers more spiritual bodies, of which we have sufficiently discoursed above. Now, let us con∣ceive that these steams find a body, of a convenient density to incorporate themselvs in, in the way of density; as we see fire doth in iron, and in other dense bodies: and this not for an hour or two, as happens in fire; but for years: as I have been told that, in the extreme cold hills in the Peak in Darby∣shire, happens to the dry Atoms of cold; which are permanently incorporated in water by long continual freezing, and so make a kind of Chrystal.

In this case, certainly it must come to pass, that this body will become in a manner, wholly of the nature of these steams; which being drawn from the Poles that abound in cold and driness, (for others, that have not these qualities, do not contribute to * 1.200 the intended effect), the body is aptest to become a stone: for so we see that cold and drought turns the superficial parts of the earth into stones & rocks; & accordingly, wherever cold & dry winds reign powerfully, all such Countries are mainly rocky.

Now then, let us suppose this stone to be taken out of the earth and hang'd in the air, or set conveniently on some little pin; or otherwise put in liberty, so as a small impulse may easily turn it any way: it will in this case certainly follow, that the

end of the stone, which in the earth lay towards the North pole, will now in the air convert it self, in the same manner, towards the same point; and the other end, which lay towards the South, turn by consequence to the South. I speak of these Countries which lie between the Equator and the North; in which of ne∣cessity the stream going from the North to the Equator must be stronger then the opposite one.

Now, to explicate how this is done. Suppose the stone hang'd East and West freely in the air; the steam, which is drawn from the North Pole of the earth, ranges along by it in its course to the Equator; and, finding in the stone the South steam (which is grown innate to it) very strong, it must needs incorporate it self with it, and most by those parts of the steam in the stone which are strongest; which are they that come directly from the North of the stone, (by which I mean that part of the stone that lay Northward in the Earth, and that still looks to the North pole of the Earth now it is in the air). And therfore, the great floud of atoms coming from the North pole of the earth will incorporate it self most strongly, by the North end of the stone, with the little floud of Southern atomes it findes in the stone: for that end serves for the coming out of the Southern atomes, and sends them abroad; as the South end doth the Nor∣thern steam, (since the steams come in at one end, and go out at the other.)

From hence we may gather, that this stone will joyn and cleave to its attractive; whenever it happens to be within the Sphere of its activity. Besides, if, by some accident it should happen, that the atomes or steams, which are drawn by the Sun from the Polewards to the Equator, should come stronger from some part of the earth, which is on the side hand of the Pole, then from the very Pole it self; in this case the stone will turn from the Pole towards that side. Lastly, whatever this stone will do towards the Pole of the earth; the very same a lesser stone of the same kind will do towards a greater. And, if there be any kind of other substance that has participation of the na∣ture of this stone, such a substance will behave it self towards this stone, in the same manner as such a stone behaves it self to∣wards the earth: all the Phenomens whereof may be the more plainly observed, if the stone be cut into the form of the earth.

And thus, we have found a perfect delineation of the Load∣stone, from its causes. For, there is no man so ignorant of the nature of a Loadstone, but he knows that the properties of it are to tend towards the North; to vary somtimes; to joyn with another Loadstone; to draw iron to it: and such like, whose causes you see deliver'd.

But, to come to experimental proofs and observations on the Loadstone, by which it will appear that these causes are well * 1.201 esteem'd and apply'd; we must be beholding to that admirable searcher of the nature of the Loadstones Dr. Gilbert: by means of whom and Dr. Harvey, our Nation may claim, even in this latter age, as deserved a crown for solid Philosophical learning; as, for many ages together, it hath done formerly for acute and subtile speculations in Divinity. But, before I fall to particulars, I think it worth warning my Reader, how this Great Man arri∣ved to discover so much of Magnetical Philosophy; that he like∣wise, if he be desirous to search into nature, may, by imitation, advance his thoughts and knowledge that way.

In short, then; all the knowledg he got of this subject was by forming a little Loadstone into the shape of the earth. By which means he compassed a wonderful design, which was, to make the whole globe of the earth maniable: for, he found the properties of the whole earth in that little body; which he therfore called a Terrella, or little earth, and which he could manage and try ex∣periences on, at his will. And in like manner, any man, that has an aim to advance much in natural Sciences, must endeavour to draw the matter he enquires of into some smal model, or into some kind of manageable method; which he may turn and wind as he pleases: and then let him be sure, if he hath a competent understanding, that he will not miss of his mark.

But, to our intent; the first thing we are to prove is, that the * 1.202 Loadstone is generated in such sort as we have described. For proof wherof, the first ground we will lay shall be to consider how, in divers other effects, it is manifest, that the differences of being exposed to the North or to the South, cause very great variety in the same thing: as hereafter, we shall have occasion to touch, in the barks and grains of trees, and the like. Next, we find by experience, that this virtue of the Loadstone is receivd

into other bodies that resemble its nature, by heatings and coo∣lings: for, so it passes in iron bars, which, being throughly heated, and then laid to cool North and South, are therby imbued with a Magnetick virtue; heat opening their bodies, and disposing them to suck in such atoms as are convenient to their nature, that flow to them whiles they are cooling. So that we cannot doubt, but convenient matter, fermenting in its warm bed un∣der the earth, becomes a Loadstone; by the like sucking in of af∣fluent streams, of a like complexion to the former.

And it fares in like manner with those fiery instruments (as fire∣forks, tongues, shovels; and the like) which stand constantly up∣wards and downwards; for they, by being often heated and cool'd again, gain a very strong verticity, or turning to the Pole: and indeed, they cannot stand upwards and downwards so little a while, but they will in that short space gain a manifest verticity; and change it at every turning. Now, since the force and vigour of this verticity is in the end that stands downwards; 'tis evident that this effect proceeds out of an influence receiv'd from the earth.

And because in a Load-stone (made into a globe, or consider'd so, to the end you may reckon Hemispheres in it, as in the great earth) either Hemisphere gives to a needle touch'd upon it, not only the virtue of that Hemisphere where it is touch'd, but like∣wise the vertue of the contrary Hemisphere: we may boldly con∣clude, that the virtue which a Loadstone is impregnated with, in the womb or bed of the earth where it is form'd and grows, pro∣ceeds as well from the contrary Hemisphere of the earth, as from that wherin it lyes; in such sort, as we have above de∣scribed. And, as we feel oftentimes in our own bodies, that some cold we catch remains in us a long while after the taking it; and somtimes seems even to change the nature of some part of our body, into which it is chiefly enter'd and hath taken particular possession of: so that, whenever new atoms of the like nature again range about in the circumstant air, that part, so deeply affected with the former ones of-kin to these, in a par∣ticular manner seems to rissent and attract them to it; and to have its guests within it (as it were) waken'd and rous'd up, by the strokes of the advenient ones that knock at their doors. Even so (but much more strongly, by reason of the longer time and

less hinderances) we may conceive, that the two virtues or a∣toms, proceeding from the two different Hemisphere, consti∣tute a certain permanent and constant nature in the stone that imbibes them: which, then, we call a Loadstone; and is exceed∣ing sensible (as we shall hereafter declare) of the advenience to it of new atoms, a like in nature and complexion to those it is impregnated with.

And this virtue, consisting in a kind of softer and tenderer substance then the rest of the stone, becomes thereby subject to be consumed by fire. From whence we may gather the reason, why a Loadstone never recovers its magnetick virtue, after it hath once lost it; though iron doth: for the humidity of iron is inseparable from its substance; but the humidity of a Load∣stone; which makes it capable of this effect, may be quite consu∣med by fire, and so the stone may be left too dry, for ever being capable of imbibing any new influence from the earth, unless it be by a kind of new making it.

In the next place, we are to prove, that the Loadstone works in that manner we have shew'd. For which end, let us consider * 1.203 how the atoms, that are drawn from each Pole and Hemisphere of the earth to the Equator, making up their course by a manudu∣ction of one another, the hindermost cannot chose but still follow on after the formost. And, as it happens in filtration by a cot∣ton cloath, if some one part of the cotton have its disposition to the ascent of the water more perfect and ready, then the other parts have; the water will assuredly ascend faster in that part, then in any of the rest: so, if the atoms find a greater disposition for their passage, in any one part of the Medium they range through, then in another; they will certainly not fail of taking that way, in greater abundance and with more vigour and strength, then any other.

But 'tis evident that, when they meet with such a stone as we have described, the helps, by which they advance in their jour∣ney, are notably encreas'd by the floud of atoms they meet coming out of that stone; which being of the nature of their opposite pole, they seise greedily upon them, and therby pluck themselvs faster on: like a Ferry man, that draws on his boat the swiftlier, the more vigourously he t••gs and pulls at the rope that lyes thwart the river for him to hale himself over by. And

therfore, we cannot doubt but this floud of atoms, streaming from the pole of the earth, must needs pass through that stone, with more speed and vigour then they can do any other way.

And, as we see in the running of water, if it meets with any lower cranies then the wide channel it streams in; it will turn out of its straight way, to glide along there where it findes an easier and more declive bed to tumble in: so these atoms will infallibly deturn themselvs from their direct course, to pass through such a stone, as far as their greater conveniency leads them.

And, what we have said of these atoms, which from the Poles range through the vast sea of air to the Equator, is likewise to be appli'd to those atoms which issue out of the stone: so that we may conclude, that, if they meet with any help which may con∣vey them on with more speed and vigour, then whiles they stream directly forwards; they will likewise deturn themselvs from directly forwards, to take that course. And, if the stone it self be hang'd so nicely, that a less force is able to turn it about, then is requisite to turn awry, out of its course, the continued stream of atoms which issues from the stone: in this case, the stone it self must needs turn towards that stream, which climb∣ing and filtring it self along the stones stream, draws it out of its course; in such sort as the nose of a Weather-cock buts it self into the wind. Now, then, it being known, that the strongest stream comes directly from the North, in the great earth; and that the Southern stream of the Terrella, or Loadstone, (pro∣portion'd duly by nature to incorporate with the North stream of the earth) issues out of the north end of the stone; it follows plainly that, when a Loadstone is situated at liberty, its North and must necessarily turn towards the North pole of the World.

And it will likewise follow, that, whenever such a stone meets with another of the same nature and kind, they must comport themselvs to one another in like sort: that is, if both of them be free and equal, they must turn themselvs to or from one ano∣ther; according as they are situated in respect of one ano∣ther. So that, if their axis be parallel, and the South pole of the one and the North of the other look the same way, they will send proprtionate and greeing streams to one another

from their whole bodies, that will readily mingle and incorpo∣rate with one another, without turning out of their way, or seek∣ing any shorter course, or chāging their respects to one another.

But, if the poles of the same denomination look the same way, and the loadstones do not lie so as to have their axis pa∣rallel, but that they incline to one another: then they will work themselvs about, till they grow, by their opposite poles, into a straight line; for the same reason, as we have shew'd of a loadstones turning to the pole of the earth.

But, if only one of the loadstones be free, and the other fixed, and that they lie inclined, as in the former case; then, the free stone will work himself, till his pole be opposite to that part of the fixed stone, from whence the stream which agrees with him issues strōgest; for that streā is to the free loadstone, as the Nor∣thern streā of the earth is to a loadstone compared to the earth. But withal, we must take notice that, in this our discourse, we abstract from other accidents; and particularly, from the influ∣ence of the earths streams into the loadstones: which will cause great variety in these cases, if they lie not due North & South, when they begin to work. And, as loadstones and other magne∣tick bodies thus of necessity turn to one another, when they are both free; and, if one of them be fast'ned, the other turns to it: so likewise, if they be free to progressive motion, they must, by a like necessity and for the same reason, come together and joyn themselves to one another. And, if only one of them be free, that must remove it self to the other; for, the same vertue that makes them turn (which is the strength of the steam) will likewise (in due circumstances) make them come together; by reason that the steams, which climbe up one another by the way of fil∣tration, and thereby turn the bodies of the stones upon their centers, when they are only free to turn, must likewise draw the whole bodies of the stones entirely out of their pla∣ces, and make them joyn; when such a total motion of the body is an effect that requires no more force, than the force of conveying vigorously the streams of both the Mag∣netick bodies into one another, that is, when there is no such impediment standing in the way of the Magnetick bodies mo∣tion, but that the celerity of the atomes motion, mingling with one another, is able to overcome it. For, then, it must needs do so; and the magnetick body, by natural coherence to the steam

of atomes in which it is involved, follows the course of the steam: in such sort as in the example we have heretofore, upon another occasion, given of an eggs-shell fill'd with dew; the Sun∣beams converting the dew into smoke, and raising up that smoke or steam, the eggs-shell is likewise rais'd up for company with the steam that issues from it.

And, for the same reason it is, that the Load-stone draws iron; For, iron being of a nature apt to receive and harbor the steams of a Loadstone, it becomes a weak loadstone, and works to∣wards a loadstone, as a weaker Loadstone would do: & so moves towards a Loadstone, by the means we have now described. And, that this conformity between iron and the Loadstone is the true reason of the Loadstones drawing iron is clear, out of this, that a Loadstone will take up a greater weight of pure iron, then it will of impure or drossie Iron, or of Iron and some other mettal joyn'd together; and that it will draw further through a slender long Iron, then in the free open air: all which are manifest signs, that iron co-operates with the force which the Loadstone grafts in it. And the reason why iron comes to a loadstone more efficaciously then another loadstone doth, is, because loadstones generally are more impure then iron is (as being a kind of Oar or Mine of Iron) and have other extrane∣ous and Heterogeneal natures mix'd with them: whereas iron receives the loadstones operation in its whole substance.

CHAP. XXI. Positions drawn out of the former Doctrine, and confirm'd by experimental proofs.

THe first Position is, that, The working of the loadstone, (be∣ing * 1.204 throughout according to the tenour of the operation of bodies) may be done by bodies; and consequently, is not done by occult or secret qualities. Which is evident out of this, that a greater loadstone has more effect then a lesser: and that, if you cut away part of a loadstone, part of his vertue is likewise taken from him; and if the parts be join'd again, the whole becomes as strong as it was before.

Again, if a loadstone touch a longer iron, it gives it less force then if it touch a shorter: nay, the vertue in any part is

sensibly lesser, according as it is further from the touched part.

Again, the longer an iron is in touching, the greater vertue it gets, and the more constant. And, both an iron and a loadstone may lose their vertue, by long lying out of their due order and situation, either to the earth or to another loadstone.

Besides, if a loadstone touch a long iron in the middle of it, he diffuses his vertue equally towards both ends; and, if it be a round plate, he diffuses his vertue equally to all sides.

And lastly, the vertue of a loadstone, as also of an iron touch∣ed, is lost by burning it in the fire. All which symptoms, agree∣ing exactly with the rules of bodies, make it undeniable, that the vertue of the loadstone is a real and solid body.

Against this position Cabeus objects, that little atomes would not be able to penetrate all sorts of bodies; as we see the ver∣tue * 1.205 of the loadstone doth: And argues, that, although they should be allow'd to do so, yet they could not be imagin'd to penetrate thick and solid bodies so suddenly, as they would do thin ones; and would certainly shew then some sign of facility or difficulty of passing, in the interposition and taking away of bodies put between the loadstone and the body it works upon. Secondly, he objects that atomes, being little bodies, cannot move in an instant; as the working of the loadstone seems to do. And lastly, that the loadstone, by such abundance of continual evaporations, would quickly be consumed.

To the first we answer, That atomes, whose nature 'tis to pierce iron, cannot reasonbly be suspected of inability to pene∣trate any other body: and, that atomes can penetrate iron, is evi∣dent, in the melting of it by fire. And indeed this objection comes now too late; after we have so largely declared the divi∣sibility of quantity, and the subtility of nature in reducing all things into extreme small parts: for, this difficulty has no other avow, then the tardity of our imaginations, in subtilizing suffici∣ently the quantitative parts that issue out of the loadstone.

As for any tardity that may be expected by the interposition of a thick or dense body, there is no appearance of such; since we see light pass through thick glasses, without giving any sign of meeting with the least opposition in its passage, (as we have a∣bove declared at large): and magnetical emanations have the advantage of light in this, that they are not obliged to straight lines, as light is.

Lastly, as for Loadstones spending themselves by still venting their emanations; odoriferous bodies furnish us with a full an∣swer to that objection: for, they continue many years palpably spending themselvs, and yet keep their odour in vigour; wheras a loadstone, if it be laid in a wrong position, will not continue half so long. The reason of the duration of both which makes the matter manifest, and takes away all difficulty: which is, that, as in the root of a vege••able there is a power to change the ad∣venient juyce into its nature; so is there, in such like things as these, a power to change the ambient air into their own sub∣stance: as evident experience shews in the Hermetike Salt, (as some modern writers call it), which is found to be repair'd, and encreas'd in its weight, by lying in the air; and the like happens to Saltpeter. And, in our present subject, experience informs us, that a Loadstone will grow stronger by lying in due position either to the earth, or to astronger Loadstone, whereby it may be better impregnated; and, as it were, feed it self with the emanations issuing out of them into it.

Our next position is, that, This virtue comes to a magnetick body, from another body; as the nature of bodies is, to require a * 1.206 being moved, that they may move. And this is evident in iron, which, by the touch, orby standing in due position near the load∣stone, gains the power of the Loadstone. Again, if a Smith, in bea∣ting his iron into a rod, observe to lay it North & South; it gets a direction to the North, by the very beating of it. Likewise, if an iron rod be made red hot in the fire, and kept there a good while together, and, when it is taken out, be laid to cool just North and South; it will acquire the same direction towards the North. And this is true not only of iron, but also of all other sorts of bodies whatever that endure such ignition: particularly of pot-earths, which, if they be moulded in a long form, and, when they are taken out of the Kiln, be laid (as we said of the iron) to cool North and South, will have the same effect wrought in them. And iron, though it has not been heated, but only continued long unmoved in the some situation of North and South in a building; yet it will have the same effect. So as it cannot be denied, but this virtue comes to iron from other bodies: wherof one must be a secret influence from the North. And this is confirmd, by a Loadstones losing its virtue (as

we said before) by lying a long time unduly disposed, either to∣wards the earth, or towards a stronger Loadstone; wherby, in stead of the former, it gains a new virtue according to that situ∣ation.

And this happens, not only in the virtue which is resident and permanent in a Loadstone, or a touch'd iron; but likewise in the actual motion or operation of them. As may be experienc'd, First, in this, that the same loadstone or touch'd iron, in the South hemisphere of the world, hath its operation strongest at that end of it which tends to the North; and in the North Hemisphere, at the end which tends to the South: each pole communicating a vigour proportionable to its own strength, in the climate where it is receiv'd. Secondly, in this, that an iron joyn'd to a Loadstone, or within the Sphere of the Loadstones working, will take up another piece of iron greater then the Loadstone of it self can hold; and, as soon as the holding iron is removed out of the sphere of the Loadstones activity, it presently lets fall the iron it formerly held up. And this is so true, that a lesser loadstone may be placed so within the sphere of a greater loadstones operati∣on, as to take away a piece of iron from the greater Loadstone: and this in virtue of the same greater Loadstone from which it plucks it; for, but remove the lesser out of the sphere of the grea∣ter, and then it can no longer do it. So that 'tis evident, in these cases, the very actual operation of the lesser Loadstone, or of the iron; proceeds from the actual influence of the greater Loadstone upon and into them. And hence we may understand, that, whenever a magnetick body works, it has an excitation from without; which makes it issue out and send its streams abroad: so as 'tis the nature of all bodies to do; and as we have given examples of the like done by heat, when we discours'd of Rarefaction.

But, to explicate this point more clearly, by entring more par∣ticularly into it. If a magnetick body lyes North and South, 'tis easie & obvious to conceive, that the streams, coming from North and South of the world, & passing through the stone, must needs excitate the virtue which is in it, and carry a stream of it along with them that way they go: But, if it lies East & West, then the streams of North and South of the earth, streaming along by the two poles of the stone, are suck'd in by them much more weakly;

yet nevertheless, sufficiently to give an excitation to the innate streams which are in the body of the stone, to make them move on in their ordinary course.

The third position is, that, The virtue of the Loadstone is a dou∣ble, and not one simple virtue. Which is manifest in an iron * 1.207 touch'd by a Loadstone: for, if you touch it only with one pole of the stone, it will not be so strong and full of the magnetike vir∣tue; as if you touch one end of it with one pole, and the other end of it with the other pole of the stone. Again, if you touch both ends of an iron with the same pole of the stone, the iron gains its virtue at that end which was last touch'd; & changes its virtue from end to end, as often as it is rub'd at contrary ends. Again, one end of the Loadstone, or of iron, touch'd will have more force on the one side of the Equator, and the other end on the other side of it. Again, the variation on the one side of the Equator, and the variation on the other side of it, have dif∣ferent laws; according to the different ends of the loadstone, or of the needle, which looks to those Poles.

Wherefore tis evident, that there is a double virtue in the loadstone; the one more powerful at one end of it, the other at the other. Yet these two virtues are found in every sensible part of the stone: for, cutting it at either end, the virtue at the con∣trary end is also diminish'd; and the whole loadstone that is left has both the same virtues, in proportion to its bigness. Besides, cut the Loadstone how you will, still the two poles remain in that line, which lay under the Meridian when it was in the earth. And the like is of the touched iron: whose virtue still ••es along the line which goes straight (according to the line of the Axis) from the point where it was touch'd; and, at the oppo∣site end, constitutes the contrary pole.

The fourth position is, that, Though the virtue of the Loadstone be in the whole body; Yet its virtue is more seen in the poles * 1.208 then in any other parts. For, by experience 'tis found, that a Loadstone, of equal bulk, works better and more efficaciously, if it be in a long form, then if it be in any other. And, from the middle line betwixt the two poles there comes no virtue, if an iron be touch'd there: but any part towards the pole, the nearer it is to the pole, the greater party it imparts. Lastly, the declina∣tion teaches us the same; which is so much the stronger, by how much it is nearer the pole.

The fifth position is, that, In the the loadstone there are ema∣nations * 1.209 which issue, not only at the poles and about them, but also spherically, round about the whole body, & in an orb from all parts of the superficies of it; in such sort as happens in all o∣ther bodies whatever: And these spherical emanations are of two kinds; proportionable to the two polar emanations: And the greatest force of each sort of them is in that Hemisphere, where the Pole is, at which they make their chief issue.

The reason of the first part of this position is, because no parti∣cular body can be exempt from the Laws of all bodies: and we have above declared, that every physical body must of necessity have an orb of fluours, or a sphere of activity, about it. The rea∣son of the second part is, that, seeing these fluours proceed out of the very substance and nature of the loadstone; they cannot choose but be found of both sorts, in every part how little soe∣ver it be, where the nature of the loadstone resides. The reason of the third part is, that, because the polar emanations tend wholly towards the poles (each of them to their proper pole); it follows that, in every Hemisphere, both those which come from the contrary Hemisphere, and those which are bred in that they go out at, are all assembled in that Hemisphere: and therefore of necessity it must be stronger in that kind of fluours, then the opposite end is. All which appears true in experience: for, if a long iron touches any part of that Hemisphere of a loadstone which tends to the North, it gains at that end a virtue of tending likewise to the North: and the same will be if an iron but hang loose over it. And this may be confirm'd, by a like experience of an iron bar, in respect of the earth; which, hanging down∣wards in any part of our Hemisphere, is imbued with the like inclination of drawing towards the North.

The sixth position is, that although every part of one load∣stone * 1.210 do in it self agree with every part of another loadstone, (that is, if each of these parts were divided from their wholes, & each of them made a whole by it self, they might be so joyn'd together as they would agree); nevertheless, when the parts are in their two wholes, they do not all of them agree together: but, of two loadstones, only the poles of the one agree with the whole body of the other; that is, each pole with any part of the contrary Hemisphere of the other loadstone.

The reason of this is, because the fluours which issue out of the stones are in certain different degrees, in several parts of the entire loadstones: wherby it happens, that one loadstone can work, by a determinate part of it self, most powerfully upon the other, if some determinate part of that other lie next it; and not so well, if any other part lies towards it. And according∣ly experience shews that, if you put the pole of a loadstone to∣wards the middle of a needle that is touch'd at the point, the middle part of the needle will turn away, and the end of it will convert it self to the pole of the loadstone.

The seventh position is, that, If a touched needle and a load∣stone come together, and touch one another in their agreeing * 1.211 parts (whatever parts of them those be); the line of the needles length will bēd towards the pole of the stone (excepting, if they touch by the Equator of the stone, & the middle of the needle): yet not so that, if you draw out the line of the needles length, it will go through the pole of the stone; unless they touch by the end of the one, and the pole of the other. But if they touch by the Equator of the one and the middle of the other, then the needle will lie parallel to the axis of the stone.

And the reason of this is manifest; for, in that case, the two poles being equidistant to the needle, they draw it equally; and by consequence, the needle must remain parallel to the axis of the stone. Nor doth it import that the inequality of the two poles of the stone is, materially or quantitatively greater then the inequality of the two polles of the needle; out of which it may at the first sight seem to follow, that the stronger pole of the stone should draw the weaker pole of the needle nearer to it self, then the weaker pole of the stone can be able to draw the stronger pole of the needle, and by consequence that the needle should not lie parallel to the axis of the stone, but incline somwhat to the stronger pole of it. For, after you have well consider'd the matter, you will find that the strength of the pole of the stone cannot work according to its material greatness; but is confined to work only according to the susceptibility of the needle: which, being a slender and thin body, cannot receive so much as a thicker body may. Wherfore, seeing the strongest pole of the stone gives most strength to that pole of the needle, which lies furthest from it; it may well happen,

that the superiority of strength in the pole of the needle, that is applied to the weaker pole of the stone, may counterpoise the excess of the stronger pole of the stone, over its opposite weaker pole: though not in greatness and quantity, yet in respect of the virtue which is communicable to the poles of the needle; wher∣by its comportment to the poles of the stone is determin'd. And indeed, the needles lying parallel to the axis of the stone, when the middle of it sticks to the equator of the stone, convinces that, upon the whole matter, there is no excess in the efficacious working of either of the stone's poles: but that their excess over one another, in regard of themselvs, is ballanced by the nee∣dles receiving it.

But, if the needle hapen's to touch the loadstone in some part nearer one pole then the other; in this case 'tis manifest that the force of the stone is greater on the one side of the needles touch, then on the other side, because there is a greater quantity of the stone on the one side of the needle then on the other: and by consequence, the needle will incline that way which the greater force draws it; so far forth as the other part doth not hinder it. Now we know that, if the greater part were divided from the rest, and so were an entire Loadstone by it self, (that is, if the Loadstone were cut off where the needle touches it); then the needle would joyn it self to the pole, that is, to the end of that part; and by consequence, would be tending to it, as a thing that is suck'd tends towards the sucker, against the motion or force which comes from the lesser part: and on the other side, the lesser part of the stone, which is on the other side of the point which the needle touches, must hinder this inclination of the needle, according to the proportion of its strength; and so it followes, that the needle will hang by its end, not directly set to the end of the greater part, but as much inclining towards it as the lesser part doth not hinder, by striving to pull it the other way. Out of which we gather the true cause of the needles de∣clination; to wit, the proportion of working of the two unequal parts of the stone, between which it touches and is joyn'd to the stone. * 1.212

And we likewise discover their errour, who judg that the part which draws iron is the next pole to the iron. For 'tis rather the contrary pole which attracts; or, to speak more

properly 'tis the whole body of the stone, as streaming in lines almost parallel to the axis, from the furthermost end, to the o∣ther next the iron: and (in our case) 'tis that part of the stone, which begins from the contrary pole and reaches to the needle. For, besides the light which this discourse gave us, experience assures us, that a Loadstone, whose poles lie broadways, not long∣ways, is more imperfect and draws more weakly then if the poles lay longways; which would not be, if the fl••ours stream'd from all parts of the stone directly to the pole: for then, how∣ever the stone were cast, the whole virtue of it would be in the poles. Moreover, if a needle were drawn freely upon the same Meridian, from one pole to the other; as soon as it were pass'd the Equator, it would leap suddenly, at the very first remove of the Equator where 'tis parallel with the axis of the Load∣stone, from being so parallele, to make an angle with the axis, greater then a half right one; ••o the end that it might look up∣on the pole, which is supposed to be the only attractive that draws the needle: which great change, wrought all at once, na∣ture never causes nor admits, but, in all actions or motions, uses to pass through all the Mediums, whenever it goes from one ex∣treme to another. Besides, there would be no variation of the needles aspect towards the North end of the stone: for, if every part sent its virtue immediately to the poles, it were impossible that any other part whatever should be stronger then the polar part, seeing that the polar part has the virtue even of that particular part, and of all the other parts of the stone beside, joyn'd in it self.

This therfore is evident, that the virtue of the loadstone goes from end to end in parallel lines; unless it be in such stones, as have their polar parts narrower then the rest of the body of the stone: for, in them, the stream will tend with some little decli∣nation towards the pole, as it were by way of refraction Because, without the stone, the fluours from the pole of the earth coarct themselvs, and so thicken their stream, to croud into the stone, as soon as they are sensible of any emanations from it; that being (as we have said before) their readiest way to pass along: and with in the stone, the stream doth the like, to meet the adve∣nient stream where it is strongest and thickest; which is at that narrow part of the stones end, which is most prominent out.

And, by this discourse, we discover likewise another errour, * 1.213 of them that imagine the Loadstone hath a sphere of activity round about it, equal on all sides; that is, perfectly spherical, if the stone be spherical. Which clearly is a mistaken speculation: for, nature having so order'd all her agents, that where the strength is greatest, there the action must (generally speaking) extend it self furthest off; and it being acknowledg'd that the Loadstone hath greatest strength in its Poles, and least in the Equator; it must of necessity follow, that it works further by its Poles, then by its Equator. And consequently, it is impossible that its sphere of activity should be perfectly spherical.

Nor doth Cabeus his experience move us, to conceive the load∣stone hath a greater strength to retain an iron laid upon it by its Equator, then by its Poles: for, to justifie his assertion, he should have tried it in an iron wire, that were so short as the poles could not have any notable operation upon the ends of it; since other∣wise, the force of retaining it wil be attributed to the Poles (ac∣cording to what we have above deliver'd) and not to the Equator.

The eighth position is, that The intention of nature, in all the * 1.214 operations of the Loadstone, is to make an union betwixt the at∣tractive and the atracted ••bodies. Which is evident out of the sticking of them together: as also out of the violence wherwith iron comes to a Loadstone; which, when it is drawn by a power∣ful one, is so great, that, through the force of the blow hitting the stone, it will rebound back, and then fall again to (the stone. And, in like manner, a needle upon a pin, if a Loadstone be set near it, turns with so great a force towards the pole of the stone, that it goes beyond it and, coming back again, the celerity wherwith it moves maketh it retire it self too far on the other side; and so, by many undulations, at last it comes to rest direct∣ly opposite to the pole. Likewise, by the declination; by means of which, the iron to the stone, or the stone to the earth, ap∣proaches in such a disposition, as is most convenient to joyn the due ends together. And lastly, out of the flying away of the contrary ends from one another: which clearly is to no other purpose, but that the due ends may come together. And in gene∣ral, there is no doubt, but ones going to another is instituted by the order of nature for their coming together; and for their being together, which is but a perseverance of their coming together.

The ninth position is, that, The nature of a Loadstone doth not sink deeply into the main body of the earth, as to have the sub∣stance * 1.215 of its whole body be magnetical; but only remans near the surface of it. And this is evident, by the inequality in virtue of the two ends: for, if this magnetick virtue were the nature of the whole body, both ends would be equally strong; For would the disposition of one of the ends be different from the disposition of the other. Again, there could be no variation of the tending towards the North: for, the bulk of the whole body would have a strength so eminently greater then the prominen∣ces and disparities of hils or seas, as the varieties of these would be absolutely insensible. Again, if the motion of the Loadstone came from the body of the earth, it would be perpetually from the center, & not from the Poles; & so, there could be no declina∣tion more in one part of the earth, then in another. Nor would the Loadstone tend from North to South, but from the centre to the circumference; or rather from, the circumference to the centre. And so we may learn the difference between the loadstone and the earth, in their attractive operations; to wit, that the earth doth not receive its influence from another body, nor doth its magne∣tick virtue depend of another magnetick agent, that impresses it into it: which, nevertheless, is the most remarkable condition of a Loadstone. Again, the stongest vertue of the Loadstone is from pole to pole; but the strongest virtue of the earth is from the centre upwards: as appears by fireforks, gaining a much greater magnetick strength in a short time, then a Loadstone in a longer. Neither can it be thence objected, that the loadstone should therfore receive the earths influences more strongly from the centerwards, then from the poles of the earth, (which by its operation, and what we have discours'd of it, is certain it doth not): since the beds, where Loadstones lie and are form'd, be to∣wards the bottome of that part or back of the earth which is im∣bued with magnetick virtue. Again, this virtue which we see in a Loadstone is substantial to it; wheras the like virtue is but acci∣dental to the earth, by means of the Suns drawing the northern and southern exhalations to the Equator. * 1.216

The last position is, that The loadstone must be found over all the earth, and in every country. And so we see it is: both because iron mines are found (in some measure) almost in all countries; &

cause, at least other sorts of the earth (as we have declared of potearths) cannot be wanting in any large extent of country, which, when they are baked and cool'd in due positions, have this effect of the Loadstone, and are of the nature of it. And Dr. Gilbert shews, that the loadstone is nothing else but the Ore of Steel or perfectest iron; and that it is to be found of all colours, and fashions, and almost of all consistences.

So that we may easily conceive, that the emanations of the Loadstone being every where, as well as the causes of gravity; the * 1.217 two motions, of magnetick and weighty things, both of them derive their origine from the same source: I mean, from the very same emanations coming from the earth; which by a di∣vers ordination of nature, make this affect in the loadstone, and that other in weighty things. And, who knows but that a like sucking, to this which we have shew'd in magnetick things, passes also in the motion of gravity? in a word, gravity bears a fair testimony in behalf of the magnetick force; and the Loadstones working returns no mean verdict for the causes of gravity: ac∣cording to what we have delivered of them.

CHAP. XXII. A Solution of certain Problemes concerning the Loadstone, and a short sum of the whole doctrine touching it.

OUt of what is said upon this subject, we may proceed to the Solution of certain questions or problemes, which are or * 1.218 may be made in this matter. And first, of that which Dr. Gil∣bert disputes, against all former writers of the Loadstone; to wit, which is the North, and which the South pole of a stone? Which seems to me only a question of the name: for if, by the name of North and South, we understand that end of the stone which has that virtue that the North or South pole of the earth have then 'tis certain, that the end of the stone which looks to the South pole of the earth is to be called the North pole of the loadstone, and contrariwise, that which looks to the North is to be called the South pole of it. But if, by the names of North and South pole of the stone, yo•• mean those ends of it, that lie and point to the North and South poles of the earth; then you

must reckon their poles contrariwise to the former account. So that, the terms being once defined, there will remain no fur∣ther controversie about the point.

Dr. Gilbert seems also to have another controversie with all * 1.219 Writers; to wit, whether any bodies besides Magnetical ones be attractive; Which he seems to deny; all others to affirm. But this also, being fairly put, will peradventure prove no con∣troversie: for the question is either in common, of attraction, or else in particular, of such an attraction as is made by the load∣one. Of the first part, there can be no doubt; as we have declar∣ed above; and is manifest betwixt gold and quicksilver, when a man holding Gold in his mouth, it draws to it the quicksilver that is in his body. But, for the attractive to draw a body to it self, not wholly, but one determinate part of the body drawn, to one determinate part of the drawer; is an attraction which, for my part, I cannot exemplifie in any other bodies but Magnetical ones.

A third question is, Whether an iron that stands long un∣moved * 1.220 in a window, or any other part of a building, perpen∣dicularly to the earth, contracts a Magnetical virtue, of drawing or pointing towards the North, in that end which looks downwards? For Cabeus (who wrote since Gilbert) affirms it out of experience: but, either his experiment or his expres∣sion was defective. For, assuredly, if the iron stands so in the Northern Hemisphere, it will turn to the North; and, if in the Southern Hemisphere, it will turn to the South: for, seeing the virtue of the loadstone proceeds from the earth, and the earth has different tempers towards the North, and toward the South pole (as hath been already declared); the virtue, which comes out of the earth in the Northern Hemisphere, will give to the end of the iron next it an inclination to the North pole, and the earth of the Southern Hemisphere will yield the con∣trary disposition to the end which is nearest it.

The next Question is, why a loadstone seems to love iron * 1.221 better then another loadstone? The answer is, because iron is indifferent in all its parts to receive the impression of a load∣stone; wheras another loadstone receives it only in a deter∣minate part: and therfore a loadstone draws iron more easi∣ly then it can another loadstone; because it finds repugnance

in the parts of another Loadstone, unless it be exactly situated in a right position. Besides, iron seems to be compared to a Loadstone, like a more humid body to a dryer of the same na∣ture: and the difference of male and female sexes in Animals manifestly shew the great appetence of conjunction between moisture and dryness, when they belong to bodies of the same species.

Another question is that great one, Why a Loadstone cap'd * 1.222 with steel takes up more iron, then it would do if it were with∣out that caping? Another conclusion like this is, that, if by a Loadstone you take up an iron, and by that iron a second iron, and then pull away the second iron; the first iron (in some po∣sition) will leave the Loadstone to stick to the second iron, as long as the second iron is within the sphere of the Loadstones activity: but, if you remove the second out of that sphere, then the first iron remaining within it, though the other be out of it, will leave the second, and leap back to the Loadstone. To the same purpose is this other conclusion; that, The greater the iron is, which is entirely within the compass of the Loadstones virtue, the more strongly the Loadstone will be moved to it, and the more forcibly stick to it.

The reasons of all these three we must give at once: for, they hang all upon on string. And, in my conceit, neither Gilbert nor Galileo have hit upon the right. As for Gilbert; he thinks that, in iron, there is originally the virtue of the loadstone; but that it is as it were asleep, till by the touch of the Load∣stone it be awaked and set on work: and therfore the virtue of bath joyn'd together is greater, then the virtue of the Loadstone alone.

But, if this were the reason, the virtue of the iron would be greater in every regard; and not only in sticking or in taking up: wheras himself confesses, that a cap'd stone draws no further then a naked stone, nor hardly so far. Besides, it would continue its virtue out of the sphere of activity of the loadstone; which it doth not. Again, seeing that, if you compare them severally, the virtue of the Loadstone is greater, then the virtue of the iron; why should not the middle iron stick closer to the stone, then to the further iron, which must of necessity have less virtue?

Galileo yeelds the cause of this effect, that, when an iron

touches an iron, there are more parts which touch one another, then when a Loadstone touches the iron: First, because the * 1.223 Loadstone hath generally much impurity in it, and therfore di∣vers parts of it have no virtue; wheras iron by being melted hath all its parts pure: and secondly, because iron can be smooth'd and polish'd more then a Loadstone can be, and therfore its superficies touches, in a manner, with all its parts: whereas divers parts of the stones superficies cannot touch, by reason of its ruggedness.

And he confirms his opinion by experience: for, if you put the head of a needle to a bare stone, and the point of it to an iron; and then pluck away the iron; the needle will leave the iron and stick to the stone; but, if you turn the needle the other way, it will leave the stone and stick to the iron. Out of which he infers that 'tis the multitude of parts, which causes the closs and strong sticking. And it seems he found the same in the caping of his Loadstones; for he used flat irons for that purpose, which by their whole plane did take up other irons: wheras Gilbert cap'd his with convex irons; which, not applying themselvs to other irons, so strongly or with so many ports as Galileo's did, would not by much take up so great weights as his.

Nevertheless, it seems not to me that his answer is suf∣ficient, or that his reasons convince. For, we are to consider that the virtue, which he puts in the iron, must (according to his own supposition) proceed from the Loadstone: and then, what imports it, whether the superficies of the iron, which touches another iron, be so exactly plain or no, or that the parts of it be more solid then the parts of the stone? For, all this conduces nothing to make the virtue greater then it was: since no more virtue can go from one iron to the other, then goes from the Loadstone to the first iron; and, if this vir∣tue cannot tie the first iron to the Loadstone, it cannot pro∣ceed out of this virtue that the second iron be tyed to the first. Again, if a paper be put betwixt the cap and another iron, it doth not hinder the magnetical virtue from passing through it to the iron; but the virtue of taking up more weight, then the naked stone was able to do, is therby render'd quite useless. Therfore, 'tis evident, that this virtue must be put in somthing else, and not in the application of the magnetical vertue.

And, to examine his reasons particularly: it may very well fall out, that, whatever the cause be, the point of a needle may be too little to make an exact experience in; and therfore a new doctrine ought not lightly be grounded upon what appears in the application of that, And likewise, the greatness of the surfaces of the two irons may be a condition helpful to the cause, what∣ever it be: for, greater and lesser are the common conditions of all bodies, and therfore avail all kinds of corporeal causes; so that no one cause can be affirm'd more then another, meerly out of this, that great doth more, and little doth less.

To come then to our own solution. I have consider'd how fire * 1.224 hath, in a manner, the same effect in iron, as the virtue of the Loadstone hath by means of the cap: for, I find that fire, co∣ming through iron red-glowing hot, will burn more strongly, then if it should come immediatly through the air; also we see that, in Pitcole, the fire is stronger then in Charcole. And ne∣vertheless, the fire will heat further if it come immediately from the source of it, then if it come through a red iron that burns more violently where it touches; and likewise charcoal will heat further then pitcoal, that near hand burns more fiercely. In the same manner, the Loadstone will draw further without a cap then with one; but with a cap it sticks faster then with∣out one. Whence I see that it is not purely the virtue of the Loadstone; but the virtue of it being in iron, which causes this effect.

Now, this modification may proceed, either from the multi∣tude of parts which come out of the Loadstone, and are as it were stop'd in the iron; & so the sphere of their activity becomes shorter, but stronger; or else, from some quality of the iron, joyn'd to the influence of the loadstone. The first seems not to give a good account of the effect: for, why should a little paper take it away, seeing we are sure that it stops not the passage of the loadstones influence? Again, the influence of the Loadstone seems in its motion to be of the nature of light, which goes in an insensible time as far as it can reach: and therfore, were it mul∣tiply'd in the iron, it would reach further then without it; and from it the virtue of the Loadstone would begin a new sphere of activity. Therfore we more willingly cleave to the latter part of our determination.

And therupon enquiring what quality there is in iron, whence this effect may follow; we find, that it is distinguish'd from a loadstone, as a metal is from a stone. Now, we know that metals have generally more humidity than stones: and we have discours'd above, that humidity is the cause of sticking; especially when it is little and dense. These qualities must needs be in iron, which of all metals is the most terrestrial: and such humidity as is able to stick to the influence of the loadstone, as it passes through the body of the iron, must be ex∣ceeding subtile and small. And it seems necessary that such hu∣midity should st••k to the influence of the loadstone, when it meets with it co••sidering that the influence is of it self dry, and that the nature of iron is a kin to the loadstone: wherfore the humidity of the one, & the drought of the other, will not fail of incorporating together. Now then, if two irons, well polish'd and plain, be united by such a glew as results ou•• of this compo∣sition; there is a manifest appearance of much reason for them to stick strongly together. This is confirm'd by the nature of iron in very cold Countreys and very cold weather: for the very humidity of the air, in times of frost, will make upon iron, sooner then upon other things, such a sticking glew as will pull off the skin of a mans hand that touches it hard.

And, by this discourse, you will perceive that Galileo's argu∣ments confirm our opinion, as well as his own; and that, ac∣cording to our doctrine, all circumstances must fall out just as they do in his experiences. And the reason is clear, why the in∣terposition of another body hinders the strong sticking of iron to the cap of the loadstone; for, it makes the mediation be∣tween them greater, which we have shew'd to be the general reason why things are easily parted.

Let us then proceed to the resolution of the other cases pro∣posed. The second is already resolv'd: for, if this glew be made of the influence of the loadstone, it cannot have force further then the loadstone it self has; and so far it must have more force then the bare influence of the loadstone. Or rather the humidity of two irons makes the glew of a fitter temper to hold, then that which is between a dry loadstone and iron: and the glew enters better when both sides are moist, then when only one is so.

But this resolution, though it be in part good, yet doth not evacuate the whole difficulty; since the same case happens be∣tween * 1.225 a stronger and a weaker Loadstone, as between a Load∣stone and iron: for, the weaker Loadstone, while it is within the sphere of activity of the greater Loadstone, draws away an iron set betwixt them, as well as a second iron doth. For the reason, therfore, of the little Loadstones drawing away the iron, we may consider, that the greater Loadstone hath two effects upon the iron betwixt it and a lesser Loadstone; and a third effect upon the little loadstone it self. The first is, that it impregnates the iron, and gives it a permanent vertue, by which it works like a weak Loadstone. The second is, that, as it makes the iron work towards the lesser Loadstone by its permanent virtue; so also it accompanies the steam that goes from the iron towards the little Loadstone, with its own steam which goes the same way: so that both these steams in company climb up the steam of the little Loadstone which meets them; and that steam climbs up the enlarged one of both theirs together. The third effect which the greater Loadstone works is, that it makes the steam of the little loadstone become stronger, by augmenting its innate vir∣tue in some degree.

Now then, the going of the iron to either of the Loadstones must follow the greater and quicker conjunction of the two meeting steams, and not the greatness of one alone. So that, if the conjunction of the two steams, between the iron and the lit∣tle Loadstone, be greater & quicker, then the conjunction of the two steams, which meet betwixt the greater Loadstone and the iron; the iron must stick to the lesser Loadstone. And this must happen more often then otherwise: for, the steam which goes from the iron to the greater Loadstone will, for the most part, be less then the steam which goes from the lesser Loadstone to the iron; &, though the other steam be never so great, yet it cannot draw more then according to the proportion of its Antago∣nists coming from the iron: Wherfore, seeing the two steams betwixt the iron and the little Loadstone are more proportiona∣ble to one another; and the steam coming out of the little load∣stone is notably greater then the steam going from the iron to the greater Loadstone: the conjunction must be made, for the most part, to the little loadstone. And, if this discourse doth not

hold in the former part of the Probleme, betwixt a second iron and Loadstone; it is supplyed by the former reason which we gave for that particular purpose.

The third case depends also of this solution: for, the bigger an iron is, so many more parts it hath to suck up the influence of the Loadstone, and consequently, doth it therby the more greedily; and therfore the Loadstone must be carried to it more violently and, when they a••e joyn'd, stick more strongly.

The sixth question is, Why the variations of the Needle from the true North, in the Northern Hemisphere, are greater the * 1.226 nearer you go to the Pole, and lesser the nearer you approach to the Equator. The reason wherof is plain in our doctrine. For, con∣sidering that the magnetick virtue of the earth streams from the North towards the Equator; it follows of necessity, that, if there be two streams of magnetick flowrs issuing from the North, one of them precisely from the pole, & the other from a part of the earth near the pole, & that the stream coming from the point by side the Pole be but a little the stronger of the two; there will appear very little differences in their several operations, after they have had a long space to mingle their emanations to∣gether, which therby join and grow as it were into one stream: wheras, the nearer you come to the Pole, the more you will find them severed, and each of them working by its own virtue. And, very near the point which causes the variation, each stream works singly by it self; and therfore here the point of variation must be master, and will carry the needle strongly to his course from the due North, if his stream be never so lit∣tle more efficacious then the other.

Again, a line drawn from a point of the Earth wide of the Pole, to a point of the Meridian near the Equator, makes a less angle; then a line drawn from the same point of the Earth, to a point of the same Meridian nearer the Pole: wherfore, the vari∣ation being esteem'd by the quantities of the said angles, it must needs be greater near the Pole, then near the Equator; though the cause be the same.

Which a little figure will presently explicate. Let the point A be the Pole, and the line AB the Meridian, and the point B the intersection of it, with a parallel near the Equator, and the point C the intersection of the Meridian with the Tro∣pick;

and D a point in the Earth near the Pole, to

[illustration]

which, in the said intersection, the needle tends, in∣stead of looking directly to the pole, wherby it make, variation from due North. I say then, that the vari∣ation of a needle near the Equator in the point B, looking upon the point D, cannot be so great and sensible, as the variation of a needle in the Tropick C, lookign upon the same point: since the angle DBA, which is made by the variation of the first, is less then the angle DCA, which it made by the variation of the latter needle, neerer the Pole,

But, because it may happen, that, in the parts near the Equa∣tor, the variation may proceed from some piece of land, not much more northerly then where the needle is, but that it bears rather Easterly or Westerly from it; and yet Gilbert's assertion goes universally, when he says the variations in Southern regions are less then in Northern ones: we must examine what may be the reason therof. And presently, the generation of the Loadstone shews it plainly. For, seeing the nature of the Loadstone pro∣ceeds out of this, that the Sun works more upon the Torrid Zone, then upon the poles; and that his too strong operation is contrary to the Loadstone, as being of the nature of fire: it follows evidently, that the lands of the Torrid Zone cannot be so magnetical (generally speaking) as the polar lands are; and by consequence, that a lesser land near the Pole will have a greater effect, then a larger continent near the Equator; and likewise, a land further off towards the Pole will work more strongly, then a nearer land which lyes towards the Equator.

The seventh question is, Whether, in the same part of the * 1.227 world, a touched needle may at one time vary more from the true North point, and at another time less? In which Gilbert was resolute for the negative part: but our latter Mathematicians are of another mind. Three experiences were made neer Lon∣don in three divers years; The two first 42 years distant from one another, and the third 12 years distant from the second: And by them it is found that, in the space of 54 years, the Load∣stone hath, at London, diminsh'd his variation from the North, the quantity of 7 degrees and more; But so that, in the latter years, the diminution hath sensibly gone faster then in the for∣mer.

These observations, peradventure, are but little credited by Strangers; but we, who know the worth of the men that made them, cannot mistrust any notable errour in them: for they were very able Mathematicians, and made their observations with very great exactness; and there were several judicious witnesses at the making of them; as may be seen in Mr. Gille∣brand's print concerning this subject. And divers other particu∣lar persons confirm the same; whose credit, though each single might peradventure be slighted, yet all in body make a great accession.

We must therfore cast about to find what may be the cause of an effect so paradox to the rest of the doctrine of the Load∣stone: for seeing that no one place can stand otherwise to the North of the earth at one time then at another; how it is possi∣ble the needle should receive any new variation, since all va∣riation proceeds out of the inequality of the earth? But, when we consider that this effect proceeds not out of the main body of the earth, but only out of the bark of it; and that its bark may have divers tempers, not as yet discover'd to us; out of whose variety the influence of the earthy parts may be divers in respect of one certain place: 'tis not impossi∣ble but that such variation may be, especially in England; which Island lying open to the North, by a great and vast Ocean, may receive, more particularly then other places, the special influences and variation of the weather, that happen in those Northeastern countreys from whence this influence comes to us. If therfore there should be any cours of weather, whose period were a hundred years (for example), or more or lesse, and so might easily pass unmarked: this variation might grow out of such a cours.

But, in so obscure a thing, we have already hazarded to guess too much. And, upon the whole matter of the Loadstone, it serves our turn, if we have proved (as we conceive we have done fully) that its motions, which appear so admirable, do not proceed from an occult quality: but that the causes of them may be reduced to local motion; and all perform'd by such corporeal instruments and means (though peradven∣ture more intricately disposed) as all other effects are among bodies. Whose ordering and disposing and particular progress

there is no reason to despair of finding ou••; would men but care∣fully apply themselvs to that work, upon solid principles and with diligent experiences.

But because this matter has been very long, and scatteringly * 1.228 diffused in many several branches; peradventure it will not be displeasing to the Reader, to see the whole nature of the load∣stone sum'd up in short. Let him then cast his eyes upon one ef∣fect of it, very easie to be tried, and acknowledg'd by all writers; though we have not as yet mention'd it: 'Tis, that a knife, drawn from the pole of a loadstone towards the Equator, if you hold the point towards the pole, gains a respect to one of the poles; but contrariwise, if the point of the knife be held towards the Equator, and be thrust the same way it was drawn before (that is, towards the Equator), it gains a respect towards the contrary pole.

'Tis evident out of this experience, that the virtue of the load∣stone is communicated by way of streams; and that in it there are two contrary streams: for otherwise the motion of the knife, this way or that why, could not change the efficacity of the same parts of the loadstone. 'Tis likewise evident, that these contrary streams come from the contrary ends of the loadstone. As al∣so, that the virtues of them both are in every part of the stone. Likewise, that one loadstone must of necessity turn certain parts of it self, to certain parts of another loadstone; nay, that it must go and joyn to it, according to the laws of attraction which we have above deliver'd: and consequently, that they must turn their disagreeing parts away from one another; and so one load∣stone seem to fly from another; if they be so apply'd that their disagreeing parts be kept still next to one another; for, in this case, the disagreeing and the agreeing parts of the same load∣stone being in the same straight line; one loadstone, seeking to draw his agreeing part near to that part of the other loadstone which agrees with him, must of necessity turn away his disa∣greeing parts, to give way to his agreeing parts to approach nearer,

And thus you see, that the flying from one another of two ends of two loadstones, which are both of the same denomina∣tion, (as for example, the two South ends, or the two North ends), doth not proceed from a pretended antipathy between

those two ends, but from the attraction of the agreeing ends.

Furthermore, the earth having to a Loadstone the nature of a Loadstone; it follows that a Loadstone must necessarily turn it self to the poles of the earth, by the same laws: and consequently, must tend to the North, must vary from the North, must incline towards the centre; and must be affected with all such accidents as we have deduced of the Loadstone.

And lastly, seeing that iron is to a Loadstone a fit matter for it to impress its nature in, and easily retains that magnetike virtue; the same effects, that follow between two Loadstones, must ne∣cessarily follow between a Loadstone and a piece of iron, fitly proportionated in their degrees: excepting some little particu∣larities, which proceed out of the naturalness of the magneticke virtue to a Loadstone, more then to iron.

And thus you see the nature of the Load-stone sum'd up in gross; the particular joynts and causes whereof, you may find treated at large in the main discourse. Wherin we have govern'd our selvs chiefly by the experiences that are recorded by Gilbert and Cabeus; to whom, we remit our Reader for a more ample de∣claration of particulars.

CHAP. XXIII. A description of the two sorts of Living Creatures, Plants and Animals: and how they are framed in common, to perform vital motion.

HItherto we have endeavour'd to follow, by a continual * 1.229 third, all such effects as we have met with among Bodies; and to trace them in all their windings, and drive them up to their very root & original source: for, the nature of our subject, having been yet very common, hath not exceeded the compass and power of our search & inquiry, to descend to the chief cir∣cumstances and particulars belonging to it. And indeed, many of the conveyance, wherby the operations we have discoursed of are performed, be so secret and abstruse; as they that Look into them, with less heedfulness and judgment then such a mat∣ter requires, are too apt to impute them to mysterious causes, above the reach of humane nature to comprehend, and to calumniate them of being wrought by occult and specifick

qualities, wherof no more reason could be given, then if the ef∣fects were infused by Angelical hands, without assistance of in∣feriour bodies; which uses to be the last refuge of ignorant men; who, not knowing what to say, and yet presuming to say some∣thing, fall often upon such expressions, as neither themselvs nor their hearers understand, but if they be well scan'd, im∣ply contradictions. Therfore, we deem'd it a kind of neces∣sity, to strain our selvs to prosecute most of such effects; even to their notional connexions with Rarity and Density. And the ra∣ther, because it hath not been our luck yet to meet with any that has had the like design, or done any considerable matter to ease our pains. VVhich cannot but make the Readers journey somwhat tedious to him, to follow all our steps; by reason of the ruggedness and untrodenness of the paths we have walk'd in.

But now, the effects we shall henceforward meddle with grow so particular, and swarm into such a vast multitude of several little joynts and wreathy labyrinths of nature; as were impos∣sible, in so summary a treatise as we intend, to deliver the causes of every one of them exactly: which would require both large discourses, and abundance of experiences, to acquit our selvs as we ought of such a task. Nor is there a like need of do∣ing it as formerly, for as much as concerns our design; since the causes of them are palpably material, and the admirable arti∣fice of them consists only in the Dedalean and wonderful-inge∣nious ordering and ranging them one with another.

VVe shall therfore intreat our Reader, from this time for∣wards, to expect only the common sequel of those particular effects, out of the principles already laid. And when some shall occur, that may peradventure seem at first sight enacted im∣mediately by a virtue spiritual, and that proceeds indivi∣sibly; in a different strain from the ordinary process which we see in bodies and bodily things (that is, by the virtues of rarity and density, working by local motion): we hope he will be satisfied at our hands, if we lay down a method, and trace out a course, wherby such events and operations may follow out of the principles we have laid. Though peradventure we shall not absolutely convince, that every effect is done just as we set it down in every particular; and that it may not as well be

done by some other disposing of parts under the same general scope: for 'tis enough for our turn, if we shew that such effects may be perform'd by corporeal agents, working as other bodies do, without confining our selvs to an exactness, in every link of the long chain that must be wound up in the performance of them.

To come then to the matter. Now that we have explicated * 1.230 the natures of those motions, by means wherof bodies are made and destroy'd; and in which they are to be consider'd chiefly as passive, whiles some exterior agent, working upon them, causes such alterations in them, and brings them to such pass, as we see in the changes that are daily wrought among substan∣ces: The next thing we are to imploy our selves about is, to take a survey of those motions which some bodies have, wher∣in they seem to be not so much patients as agents, and con∣tain within themselvs the principle of their own motion, ha∣ving no relation to any outward object, more then to stir up that principle of motion and set it on work; which, when it is once in act, hath, as it were within the limits of its own king∣dom and sever'd from commerce with all other bodies what∣ever, many other subaltern motions over which it presides.

To which purpose we may consider, that, among the com∣pounded bodies, whose natures we have explicated, there are some, in whom the parts of different complexions are so small & so wel mingled together, that they make a compound which, to our sense, seems all quite through of one Homogeneous na∣ture; and, however it be divided, each part retains the entire and compleat nature of the whole. Others again there are, in which 'tis easie to discern that the whole is made up of several great parts, of very differing natures and tempers.

And of these there are two kinds: one, of such as their dif∣fering parts seem to have no relation to one another, or corre∣spondence together to perform any particular work, in which all of them are necessary, but rather they seem to be made what they are by chance and accident; and, if one part be sever'd from another, each is an entire thing by it self, of the same na∣ture as it was in the whole, and no harmony is destroy'd by such division. As may be observ'd in some bodies dig'd out of Mines, in which one may see lumps of Metal, or stone,

and glass, and such different substances, in their several distinct situations, perfectly compacted into one continuate body; which if you divide, the glass remains what it was before, the Eme∣rald is still an Emerald, the silver is good silver, and the like of the other substances: the causes of which may be easily deduced, out of what we have formerly said. But, there are other bodies, in which this manifest and notable difference of parts carries with it such a subordination of one of them to another, as we cannot doubt but that nature made such engines (if so I may call them) by design, and intended that this variety should be in One thing; whose unity and being what it is, should depend of the harmony of the several differing parts, and should be de∣stroy'd by their separation. As we see in living Creatures, whose particular parts and members being once sever'd, there is no longer a living creature to be found among them.

Now, of this kind of bodies there are two sorts. The first is * 1.231 of those that seem to be one continuate substance, wherin we may observe one and the same constant progress throughout, from the lowest to the highest part of it; so that the operation of one part is not at all different from that of another: but the whole body seems to be the course and throughfare of one con∣stant action, varying it self in divers occasions and occurrences, according to the disposition of the subject.

The bodies of the second sort have their parts so notably se∣parated one from the other, and each have such a peculiar mo∣tion proper to them, that one might conceive they were every one a complete distinct total thing by it self, and that all of them were artificially tied together: were it not that the subordination of these parts to one another is so great, and the correspondence between them so strict, (the one not be∣ing able to subsist without the other, from whom he derives what is needful for him; and again, being so useful to that o∣ther, and having its action and motion so fitting and necessary for it, as without it that other cannot be), as plainly convinces that the compound of all these several parts must needs be one individuol thing. * 1.232

I remember that, when I travel'd in Spain, I saw there two Engines that, in some sort, express the natures of these two kinds of bodies; One at Toledo, the other a Segovia: both

of them set on work by the current of the river in which the foundation of their machine was laid. That at Toledo was to force up water at a great height, from the river Tagus to the Al∣cazar (the Kings palace), that stands upon a high steep hill or rock, almost perpendicular over the river. In the bottome there was an indented wheel, which, turning round with the stream, gave motion at the same time to the whole engine; which consisted of a multitude of little troughs or square ladles, set one over another in two parallel rows over against one another, from the bottom to the top, and upon two several divided frames of timber. These troughs were closed at one end with a traverse board, to retain the water from running out there; which end, being bigger then the rest of the trough, made it somewhat like a ladle; and the rest of it seem'd to be the han∣dle with a channel in it; the little end of which channel or trough was open, to let the water pass freely away. And these troughs were fasten'd by an axletree in the middle of them, to the frame of timber that went from the bottome up to the top: so that they could upon that center move at liberty, either the shut end downwards, or the open end; like the beam of a bal∣lance.

Now, at a certain position of the root-wheel (if so I may call it), all one side of the machine sunk down a little lower towards the water; and the other was raised a little higher: Which mo∣tion was changed, as soon as the ground-wheel had ended the remnant of his revolution; for then the side that was lowest be∣fore sprung up, and the other sunk down: And thus the two sides of the machine were like two legs, that by turns trod the water; as in the Vintage men press Grapes in a watte. Now, the troughs, that were fast'ned to the timber which descended, turn'd that part of them downwards which was like a Box shut to hold the water; and consequently, the open end was up in the air, like the arm of the ballance to which the lightest scale is fasten'd: and in the mean time, the troughs upon the ascending timber were moved by a contrary motion, keeping their box∣ends aloft, and letting the open ends incline downwards; so that, if any water were in them, they would let it run out, wher'as the others retain'd any that came into them.

VVhen you have made an image of this Machine in your

phantasie, consider what will follow out of its motion. You will perceive that, when one leg sinks down towards the water, that trough which is next to the Superficies of it, putting down his box end and dipping it a little in the water, must needs bring up as much as it can retain, when that leg ascends: which when it is at its height, the trough moves upon his own centre, & the box end, which was lowest, becomes now highest; and so the water runs out of it. Now, the other leg descending at the same time, it falls out that the trough on its side, which would be a step above that which hath the water in it if they stood in equilibri∣ty, becomes now a step lower then it; and is so placed, that the water, which runs out of that which is aloft, falls into the head or box of it: which no sooner hath receiv'd it, but that leg on which it is fastned springs up, and the other descends; so that the water of the second leg runs now into the box of the first leg, that is next above that which first laded the water out of the river. And thus, the troughs of the two legs deliver their water by turns from one side to the other; and at every re∣move, it gets a step upwards, till it comes to the top: whiles at every ascent and descent of the whole side, the lowest ladle or trough takes new water from the River; which ladleful fol∣lows immediately in its ascent that which was taken up the time before. And thus, in a little while, all the troughs from the bottom to the top are full; unless there happen to be some failing in some ladle: and in that case the water breaks out there, and all the ladles above that are dry.

The other Engine, or rather multitude of several engines, to * 1.233 perform sundry different operations, all conducing to one work (wheras, that of Toledo is but one tenour of motion, from the first to the last,) is in the Mint at Segovia. Which is so artificially made, that one part of it distends an Ingot of Silver or Gold, into that breadth and thickness as is requisite to make Coyn of. Which being done, it delivers the plate it has wrought to another, that Prints the Figure of the Coyn upon it. And from thence it is turn'd over to another, that cuts it accord∣ing to the Print, into due shape and weight. And lastly, the several pieces fall into a reserve, in another room: where the Officer, whose charge it is, findes Treasure ready Coyned; without any thing there, to inform him of the several

different motions that the silver or the gold passed, before they came to that state. But, if he go on the other side of the wall, into the room where the other machines stand and are at work; he will then discern that every one of them, which consider'd by it self might seem a distinct complete engine, is but a serving part of the whole, whose office is to make money: and that, for this work any one of them, separated from the rest, ceases to be the part of a mint, and the whole is malm'd and destroy'd.

Now, let us apply the consideration of these different kinds of Engines to the natures of the bodies we treat of. Which, I doubt * 1.234 not, would fit much better, were they lively and exactly descri∣bed: But it is so long since I saw them, and I was then so very young, that I retain but a confused and cloudy remembrance of them, Especially, of the mint at Segovia, in the which there are many more particulars then I have touched; as, conveniency for refining the ore or metal, and then casting it into ingots, and driving them into rods, and such like: to all which there is little help of hands requisite, more then to apply the matter du∣ly at the first. But, what have I said of them is enough, to illu∣strate what I aim at; and though I should erre in the particu∣lars, 'tis no great matter; for, I intend not to deliver the history of them; but only, out of the remembrance of such noteful and artificial masterpieces, to frame a model, in their phancies that shall read this, of something like them, wherby they may, with more ease, make a right conception of what we are handling.

Thus then, all sorts of plants, both great and small, may be compared to our first engine of the waterwork at Toledo. For in them all the motion, we can discern, is of one part transmit∣ting to the next to it the juyce received from that immedi∣ately before it: so that it hath one constant course, from the root (which sucks it from the earth) to the top of the high∣est spring; in which if it should be intercepted and stopt by any maiming of the bark (the channel it ascends by), it would there break out and turn into drops, or gum, or some such o∣ther substance as the nature of the plant requires; and all that part of it to which none of this juice can ascend would dry and wither and grow dead.

But Sensible living creatures we may fitly compare to the se∣cond machine of the Mint at Segovia. For in them, though every

part and member be as it were a complete thing of it self; yet every one requires to be directed and put on in its motion by another: and they must all of them (though of very different natures and kinds of motion) conspire together, to effect any thing that may be for the use and service of the whole. And thus we find in them perfectly the nature of a mover and a movea∣ble: each of them moving differently from one another, and fra∣ming to themselvs their own motions in such sort as is most agreeable to their nature; when that part which sets them on work hath stir'd them up.

And now, because these parts (the movers and the moved) are parts of one whole; we call the entre thing Automatum or se••mo∣vens, or a Living Creature. Which also may be fitly compared to a Joyner, or a Painter, or other craftsman; that had his tools so exactly fitted about him, as, when he had occasion to do any thing in his trade, his tool for that action were already in the fittest position for it to be made use of: so as, without removing himsef from the place where he might sit invironed with his tools, he might, by only pulling of some little cords, either apply the matter to any remote tool, or any of his tools to the matter he would work upon; according as he findes the one or the other more convenient for performance of the actions he intends.

Wheras in the other, there is no variety of motions; but one and the same goes quite through the body, from one end of it to the other. and the passage of the moisture through it, from one part to another next (which is all the motion it hath), is, in a manner, but like the rising of water in a Stil; which by heat is made to creep up by the sides of the glass, and from thence runs through the nose of the Limbeck, and falls into the receiver. So that, if we will say that a Plant lives, or that the whole moves it self, and every part moves another; 'tis to be understood in afar more imperfect manner, then when we seak of an Animal: and the same words are attributed to both, in a kind of equivocal: sense. But, by the way I must note, that under the title of Plants, I include not Zoophytes or Plant Animals; that is, such creatures as, though they go not from place to place, and so cause a local motion of their whole substance, yet in their parts they have a distinct and articulate motion.

But, to leave comparisons, and come to the proper nature of the

things. Let us frame a conception, that, not far under the super∣ficies of the earth, there were gather'd together divers parts of * 1.235 little mixed bodies, which in the whole sum were yet but little: and that this little mass had some excess of fire in it; such as we see in wet Hay, or in muste of wine, or in woort of beer, and that withal, the drought of it were in so high a degree, as this heat should not find means (being too much compressed) to play his game: and that, lying there in the bosome of the earth, it should, after some little time, receive its expected and desired drink, through the benevolence of the heaven; by which it being moistned, and therby made more pliable and tender and easie to be wrought upon, the little parts of fire should break loose, and, finding this moisture a fit subject to work upon, should drive it into all the parts of the little mass, and digesting there should make the mass swel. Which action, taking up long time for its performance, in respect of the small increase of bulk made in the mass by the swelling of it, could not be hindred by the pressing of the earth, though lying never so weightily upon it: according to the maxime we have above deliver'd, that any little force, be it never so little, 'tis able to overcome any great resistance, be it never so powerful; if the force multiply the time it works in, sufficiently to equalize the proportions of the agent and the re∣sistant.

This increase of bulk and swelling of the lettle mass will, of its own nature, be towards all sides, by reason of the fire & heat that occasions it (whose motion is on every side, from the centre to the circūference): but it wil be most efficacious upwards, towards the air, because the resistance is least that way; both by reason of the little thickness of the earth over it, as also by reason that the uper part of the earth lies very loose and is exceeding po∣rous, through the continual operation of ••e Sun, and fal∣ling of rain upon it. It cannot choose therfore but mount to the air; and the same cause that makes it do so presses, at the same time, the lower parts of the mass downwards. But, what ascends to the air must be of the hotter and more moist parts of the fermenting mass; and what goes downwards must be of his harder and drier parts, proportionate to the con∣trary motions of fire and earth, which predominate in these two kinds of parts, Now, this that is push'd upwards com∣coming

above ground, and being there exposed to Sun and wind, contracts thereby a hard and rough skin on its outside; but within is more tender: in this sort it defends it self from outward injuries of weather, whiles it mounts; and by thrust∣ing other parts down into the earth, it holds it self steadfast, that, although the wind may shake it, yet it cannot overthrow it. The greater this Plant grows, the more juice daily ac∣crews to it, and the heat is encreased; and consequently, the greater abundance of humours is continually sent up. Which when it begins to clog at the top, new humours pressing upwards forces a breach in the skin: and so a new piece, like the main stem, is thrust out and begins on the sides; which we call a Branch. Thus is our Plant amplified; till nature, not being able still to breed such strong issues, falls to works of less labour, and pushes forth the most ela∣borate part of the plants juice into more tender substances, but especially, at the ends of the branches, where abundant humour, but at the first not well concocted, grows into the shape of a Button; and more and better concocted humour succeeding, it grows softer and softer (the Sun drawing the subtilest parts outwards), excepting what the coldness of the air and the roughness of the wind harden into an outward skin. So then, the next parts to the skin are tender; but the very middle of this button must be hard and dry, by reason that the Sun from without, and the natural heat within, drawing and driving out the moysture and extending it from the center, must needs leave the more earthy parts much shrunk up & hardned by their evaporating out from them: which hardning being an effect of fire within and without, that bakes this hard sub∣stance, incorporates much of it self with it; as we have formerly declared in the making of salt by force of fire. This button, thus dilated and brought to this pass, we call the Fruit of the Plant: whose harder part encloses oftentimes another, not so hard as dry. The reason whereof is, because the outward hardness permits no moisture to soake, in any abundance, through it; and then, that which is enclosed in it must needs be much dried; though not so much, but that it still retains the common nature of the plant. This drought makes these in∣ner parts to be like a kind of dust; or at least, such as

may be easily dried into dust, when they are bruised out of the husk that incloses them: And, in every parcel of this dust, the nature of the whole resides, as it were, contracted into a small quantity. For, the juice which was first in the button, and had passed from the root through the manifold varieties of the di∣vers parts of the plant, and suffer'd much concoction, partly from the Sun, and partly from the inward heat imprison'd in that har∣der part of the fruit, is, by these passages strainings and concocti∣ons, become at length to be like a tincture extracted out of the whole plant; and and is at last dried up into a kind of magistery. This we call the Seed: which is of a fit nature, by being buried in the earth and dissolv'd with humour, to renew and reciprocate the operation we have thus described. And thus, you have the formation of a Plant.

But a Sensitive Creature being compared to a Plant, as a plant is to mixed body; you cannot but conceive that he must be * 1.236 compounded, as it were, of many plants; in like sort as a plant is of many mixed bodies. But so, that all the Plants, which concur to make one Animal, are of one kind of nature and cognation: and besides, the matter of which such diversity is to be made, must of necessity be more humid and figurable, then that of an ordinary plant; and the Artificer which works and moulds it, must be more active. Wherfore, we must suppose that the mass, of which an Animal is to be made, must be actually li∣quid: and the fire that works upon it, must be so powerful, that, of its own nature, it may be able to convert this liquid matter into such breaths and steams, as we see use to rise from water, when the Sun or fire works upon it. Yet, if the mass were altogether as liquid as water, it would vanish away by heat boyling it, and be dried up; therfore, it must be of such a convenient temper, that, although in some of its parts it be fluid and apt to run, yet by others it must be held together; as we see that unctu∣ous things for the most part are; which will swell by heat, but not fly away.

So then, if we imagine a great heat to be imprison'd in such a liquor; and that it seeks by boyling to break out, but that the solidness and viscousness of the substance will not permit it to evaporate: it cannot chuse but comport it self in some such sort as we see butter or oyl in a frying-pan over the fire, when

it rises in bubbles; but much more efficaciously. For, their body is not strong enough to keep in the heat, and therfore those bub∣bles fall again; wheras, if it were, those bubbles would rise high∣er and higher, and stretch themselvs longer and longer (as when the Soap-boylers boyl a strong unctuous lye into Soap), and every one of them would be as it were a little brook wherof the channel would be the enclosing substance, and the inward smoak that extends it might be compared to the water of it: as when a glass is blown out by fire and air into a long figure.

Now we may remember, how we have said, where we treated of the Production and Resolution of Mixed bodies, that there are two sorts of liquid substantial parts, which by the operation of fire are sent out of the body it works upon; the watery, and the oyly parts. For, thouh there appear somtimes some very subtile and Ethereal parts of a third kind (wich are the Aquae Ardentes, or borning spirits;) yet in such a close distilling of circulation as this is, they are not sever'd by themselvs, but accompany the rest: and especially the watery parts, which are of a nature, that the rising Ethereal spirits easily mingle with, and extend themselves in it; wherby the water becomes more efficacious, and the spiritt less fugitive.

Of these liquid parts which the fire sends away, the watry ones are the first, as being the easiest to be raised: the oyly parts rise more difficultly, and therfore come last. And in the same manner it happens in this emission of brooks; the wa∣try and oyly steams will each of them fly into different re∣servs: and if there arrive to them abundance of their own qua∣lity, each of them must make a substance of its own nature; by by setling in a convenient place, and by due concoction. Which substance after it is made and confirm'd, if more humidity and heat press it, will again break forth into other little channels. But, when the watry and oyly parts are boyl'd away, there remain yet behind other more solid and fixed parts, and more strongly incorporated with fire then either of these: which yet cannot drie up into a fiery salt, because a conti∣nual accession of humour keeps them always flowing; and so they become like a cauldron of boyling fire. Which must propagate it self as wide as either of the other; since the

activity of it must needs be greater then theirs (as being the source of motion to them) and that there wants not humidity for it to extend it self by.

And thus you see three roots of three divers plants, all in the same plant, proceeding by natural resolution from one primi∣tive source. Wherof that which is most watry is fittest to fabri∣cate the body and common outside of the triformed plant: since, water is the most figurable principle in nature, and most susceptible of multiplication and by its cold is easiest to be hard∣ned, and therfore fittest to resist the injuries of enemy-bodies that may infest it. The oily parts are fittest for the continuance and solidity of the plant: for, we see that viscuosity and oyliness hold together the parts where they abound; and they are slowly wasted by fire, but conserve and are an aliment to the fire that consumes them. The parts of the third kind are fittest for the conservation of heat: which, though in them it be too vio∣lent, yet is necessary for working upon other parts, and main∣taining a due temper in them.

And thus we have armed our plant with three sorts of ri∣vers or brooks to run through him, with as many different streams: the one of a gentle balsamike oyle; another, of streaming fire; and the third, of a con-natural and cooler water to irrigate and temper him. The streams of water (as we have said) must run through the whole fabrick of this triformed plant: and because it is not a simple water, but warm in a good degree, and as it were a middle sub∣stance betwixt water and air (by reason of the ardent vola∣tile spirit that is with it), 'tis of a fit nature to swell, as air doth; and yet withall to resist violence in a conveni∣ent degree, as water doth. Therfore, if from its source na∣ture sends abundance into any one part, that part must swell and grow thicker and shorter; and so must be contracted that way which nature has order'd it. Whence we perceive a means, by which nature may draw any part of the outward fabrick which way soever she is pleased, by set instruments for such an effect. But, when there is no motion, or but little, in these pipes, the standing stream, that is in a very little, though long, channel, must needs be troubled in its whole body; if any one part of it be press'd upon, so as to receive therby any impression: and ther∣fore

whatever is done upon it, though at the very furthest end of it, makes a commotion and sends an impression up to its very source. Which appearing, by our former d scourse, to be the origine of particular and accasional motion; 'tis obvious to conceive how it is apt to be moved and wrought by such an im∣pression, to set on foot the begining of any motion; which by na∣tures providence is convenient for the plant, when such an im∣pression is made upon it.

And thus you see this plant hath the virtue both of sense or feeling; that is, of being moved and effected by extern objects, lightly striking upon it; as also of moving it self, to or from such an object; according as nature shall have ordain'd. Which in sum is, that This Plant is a Sensitive Creature, composed of three sources, the Heart, the Brain, and the Liver; whose off-springs are the Arteries, the Nervs, and the Veins: which are fil'd with Vital Spirits, with Animal Spirits, and with Bloud; and by these the Animal is heated, nourished, and made partaker of Sense and Motion.

Now, refering the Particular motions of Living Creatures to another time: we may observe, that both kinds of them, as well Vegetables as Animals, agree in the nature of sustaining them∣selvs in the three common actions of generation, nutrition, and augmentation; which are the begining, the progress, and the conserving of life. To which three we may add the (not so much action as) passion of Death; and of Sickness or decay, which is the way to death.

CHAP. XXIV. A more particular survey of the generation of Animals, in which is discover'd what part of the Animal is first generated.

TO begin then with examining how Living Creatures are in▪ gender'd: our main question shall be, Whether they be * 1.237 framed entirely at once; or successively, one part after another? And, if this latter way; which part first? Upon the discussion of which, all that concerns generation will be explicated; as much as concerns our purpose in hand. To deduce this from its ori∣gine, we may remember how our Masters tell us, that, when any living creature is past the heat of its augmentation or

growing; the superfluous nourishment settles it self in some ap∣pointed place of the body, to serve for the production of some other. Now it is evident, that this superfluity comes from all parts of the body, and may be said to contain in it, after some sort, the perfection of the whole living creature. Be it how it will, 'tis manifest that the living creature is made of this super∣fluous moysture of the parent: which, according to the opinion of some, being compounded of several parts derived from the several limbs of the parent, those parts, when they come to be fermented in convenient heat and moysture, take their posture and situation, according to the posture and disposition of parts that the living creature had from whence they issued; and then they growing daily greater and solider (the effects of moysture and heat,) at length become such a creature as that was, from whence they had their origine.

Which an accident, that I remember, seems much to con∣firm. It was of a Cat, that had 'tis, tail cut off when it was very young: which Cat hapning afterwards to have young ones, half the kitlings proved without tails, and the other half had them in an ordinary manner; as if nature could supply but on one partners side, not on both. And another particular, that I saw when I was at Argiers, makes to this purpose: which was a wo∣man that having two thumbs upon the left hand; four daugh∣ters that she had all resembled her in the same accident, and so did a little child, a girl of her eldest daughters; but none of her sons. Whiles I was there, I had a particular curiosity to see them all: and though it be not easily permited to Christans, to speak familiarly with Mahometan women; yet the condition I was in there, and the civillity of the Basha, gave me the oppor∣tunity of full view and discourse with them. And the old woman told me, that her mother and grandmother had been in the same manner. But, for them it rests upon her credit: the others I saw my self.

But the opinion which these accidents seem to support, though at the first view it seems smoothly to satisfie our inquiry, and * 1.238 fairly to compass the making of a living creature; yet, looking further into it, we shall find it fall exceeding short of its promi∣sing, and meet with such difficulties, as it cannot overcome. For first, let us cast about how this compound of several parts, that

servs for the generation of a new living creature, can be ga∣ther'd from every part and member of the parent: so to carry with it in little the complete nature of it. The meaning hereof must be, that this superfluous aliment either passes through all and every little part and particle of the parents body; and in its passage receives somthing from them: or else, that it receives only from all similiar and great parts.

The former seems impossible; for, how can one imagine that such juice should circulate the whole body of an Animal, and visit every atome of it, and retire to the reserve where it is kept for generation; and no part of it remain absolutely behind, sticking to the flesh or bones that it bedews, but that still some part returns back from every part of the Animal? Besides, con∣sider those parts that are most remote from the channels which convey this juyce how, when they are fuller of nourishment then they need, the juyce which overflows from them comes to the next part and, setling there and serving it for its due nourishment, drives back into the channel that which was be∣twixt the channel and it self: so that here there is no return at all from some of the remote parts; and much of that juyce which is rejected never went far from the channel it self. We may therfore safely conclude, that 'tis impossible every little part of the whole body should remit somthing impregnated and imbued with the nature of it.

But then you may peradventure say, that every similiar part doth. If so, I would ask, how it is possible that, by fermentation only, every part should regularly go to a determinate place, to make that kind of Animal, in which every similiar part is diffu∣sed to so great an extent? How should the nature of flesh here become broad there round, and take just the figure of the part it is to cover? How should a bone here be hollow, there be bla∣dy, and in another part take the form of a rib; and those many figures which we see of bones? And the like we might ask of every other similiar part; as, of the veins, and the rest. Again, see∣ing it must of necessity happen, that at one time more is remitted from one part then from another; how comes it to pass that, in the collection, the due proportion of nature is so punctually ob∣served? Shall we say that this is done by some cunning artificer, whose work it is to set all these parts in their due posture; which

Aristotle attributes to the seed of the male? But this is impossi∣ble: for, all this diversity of work is to be done at one time, and in the same occasions; which can no more be effected by one a∣gent, then multiplicity can immediately proceed from unity.

But, besides that there can be no agent to dispose of the parts when they are gather'd; 'tis evident that a sensitive creature may be made, without any such gathering of parts beforehand from another of the same kind: for else, how could vermine breed out of living bodies or out of corruption? How could Rats come to fill ships; into which never any were brought? How could Frogs be ingendred in the air? Eels, of dewy turfs, or of mud? Toads, of Ducks? Fishs of Herns? and the like. To the same purpose, when one species or kind of Animal is changed into another; as when a Caterpillar or a Silk-worm becomes a Flie, 'tis manifest, there can be no such precedent collection of parts.

And therfore, there is no remedy but we must seek out some other means and course of generation, then this. To which we * 1.239 may be lead, by considering how a Living Creature is nourish'd and augmented: for why should not the parts be made in Ge∣neration, of a matter lik that which makes them in Nutrition? If they be augmented by one kind of juyce that, after several changes, turns at length into flesh and bone, and every sort of mixed body or similiar part, wherof the sensitive creature is compounded; and that joyns it self to what it finds already made: why should not the same juyce, with the same progress of heat and moysture and other due temperaments, be converted at first into flesh and bone; though none be formerly there to joyn it self to?

Let us then conclude that the juyce, which serves for nourish∣ment of the Animal, being more then is requisite for that ser∣vice; the superfluous part of it is drain'd from the rest, and re∣serv'd in a place fit for it: where by little and little, through di∣gestion, it gains strength and vigour and spirits to it self, and be∣comes an homogeneal body (such as other simple compounds are); which, by other degrees of heat & moisture, is chang'd into another kind of substance, & that again by other temperaments, into an other. And thus, by the course of nature, and by passing successively many degrees of temper, and by receiving a total

change in every one of them; at length an Animal is made, of such juice as afterwards serves to nourish him.

But, to bring this to pass a shorter way, and with greater faci∣lity, * 1.240 some have been of opinion, that all similar things, of what∣ever substance, are undiscernably mixed in every thing that is: and that, to the making of any body, out of any thing, there is no more required, but to gather together those parts which are of that kind; and to separate, and cast away from them, all those which are of a nature differing from them.

But, this speculation will appear a very aiery and needless one, we consider into how many several substances the same species of a thing may be immediately changed; or rather, how many several substances may be encreas'd immediately from several equal individuals of the same thing: and then take an account, how much of each individual is gone into each substance which it hath so increas'd, For, if we sum up the quantities that, in the several substances, are therby encreas'd; we shall find they very much exceed the whole quantity of any one of the individuals: which should not be, if the supposition were true; for, every individual should be but one one total, made up of the several different similar parts, which encrease the several substances, that extract out of them what is of their own nature.

This will be better understood by an example. Suppose that a Man, a Horse, a Cow, a Sheep, and 500 more several species of living creatures should make a meal of Letuces. To avoid all perplexity in conceiving the argument, let us allow that every one did eat a pound: and let us conceive another pound of this herb to be burned; as much to be putrified under a Cabage root, and the like under 500 plants more of divers species. Then cast how much of every pound of letuce is turned into the substances that are made of them, or encreas'd by them; as, how much ashes one pound hath made, how much water hath been distil'd out of another pound; how much a man hath been encreas'd by a third; how much a horse by a fourth, how much earth by the putrefaction of a fifth pound, how much a Cabage hath been en∣creas'd by a sixth: and so go over all the pounds that have been turned into substances of different species (which may be mul∣tiplied as much as you please.) And when you have sum'd up

all these several quantities, you find them far to exceed the quantity of one pound: which it would not do, if every pound of Letuce were made up of several different similiar parts actually in it, that are extracted by different substances of the natures of those parts; and that no substance could be encreas'd by it, unless pats of its nature were originally in the letuce.

On the other side, if we but cast our eye back upon the prin∣ciples we have laid, where we discourse of the composition of * 1.241 bodies; we shall discern how this work of changing one thing into another, either in nutrition, in augmention, or in genera∣tion, will appear not only possible, but easie to be effected. For, out of them 'tis made evident, how the several varieties of so∣lid and liquid bodies, all differences of natural qualities, all con∣sistences, and whatever else belongs to similar bodies, results out of the pure and single mixture of rarity and density: so that, to make all such varieties as are necessary, there's no need of mingling or separating any other kinds of parts; but only an art or power to mingle, in due manner, plain rare and dense bodies one with another. Which very action, and none other, (but with excellent method and order, such as be∣comes the great Architect that hath design'd it) is perform'd in the generation of a living creature; which is made of a substance at first far unlike what it afterwards grows to be.

If we look upon this change in gross, and consider but the two extremes; to wit, the first substance of which a living creature made, and it self in its full perfection: I confess, it may well seem incredible, how so excellent a creature can derive its origine from so mean a principle, and so far remote and differ∣ing from what it grows to be. But, if we examine it in retail, and go along anatomizing it in every step and degree that it changes by: we shall find that every immediate change is so near, and so palpably to be made by the concurrent causes of the mat∣ter prepared; as we must conlude, it cannot possibly become any other thing then just what it doth become.

Take a Bean, or any other seed; and put it into the earth▪ and let water fall upon it: can it be but the bean must swell? The bean swelling, can it chuse but break the skin? The skin broken, can it chuse (by reason of the heat that is in it)

but push out more matter, and do that action which we may call germinating? Can these germs chuse but pierce the earth in small strings, as they are able to make their way? Can these strings chuse but be harden'd, by the compression of the earth, and by their own nature; they being the heaviest parts of the fermented bean? And can all this be any thing else but a root? Afterwards, the heat that is in the root mingling it self with more moisture, and according to its nature, springing upwards; will it not follow necessarily, that a tender green substance (which we call a bud, or leaf must appear a little above the earth: since tenderness, greenness, and ascent, are the effects of those two principles, heat & moisture? And, must not this green substance change from what it was at first, by the Sun and Air working upon it, as it grows higher; till at length it hardens in∣to a stalk? All this while, the heat in the root sublimes up more moisture; which makes the stalk at first grow rank, and en∣crease in length. But, when the more volatile part of that warm juice is sufficiently depured and sublimed; will it not attempt to thrust it self out beyond the stalk, with much vigour and smart∣ness? And, as soon as it meets with the cold air in its eruption, will it not be stop'd and thick'ned? And, new parts flocking still from the root; must they not clog that issue, and grow into a button, which will be a bud? This bud being hard'ned at the sides, by the same causes which hard'ned the stalk, and all the while the inward heat still streaming up, & not enduring to be long enclosed, especially when, by its being stop'd, it multiplyes it self), will it not follow necessarily, that the tender bud must cleave and give way to that spiritual juice; which, being purer then the rest (through its great sublimation), shews it self in a purer and nobler substance than any that is yet made, and so becomes a flower? From hence, if we proceed as we have be∣gun and weigh all circumstances, we shall see evidently, that another substance must needs succeed the flower; which must be hollow and contain a fruit in it: and that this fruit must grow bigger and harder. And so, to the last period of the generati∣on of new beans.

Thus, by drawing the thrid carefully along through your fingers, and staying at every knot to examine how it is tyed; you see, that this difficult progress of the generation of living

creatures is obvious enough to be comprehended: and that the steps of it are possible to be set down; if one would but take the pains and afford the time that is necessary (less then that Philo∣sopher, who for so many years gave himself wholy up to the single observing of the nature of Bees) to note diligently all the circumstances in every change of it. In every one of which the thing that was becoms absolutely a new thing; and is endew'd with new properties and qualities, different from those it had before; as Physicians, from their certain experience, assure us. And yet every change is such, as, in the ordinary and general course of nature, (wherin nothing is to be consider'd, but the necessary effects following out such Agents working upon such patients, in such circumstances) 'tis impossible that any other thing should be made of the precedent, but that which is imme∣diately subsequent to it.

Now, if all this orderly succession of mutations be necessarily made in a Bean, by force of sundry circumstances and external accidents: why may it not be conceiv'd, that the like is also done in sensible creatures; but, in a more perfect manner, they being perfecter substances? Surely the progress we have set down is much more reasonable, then to conceive that, in the meal of the Bean, are contain'd, in little, several similar substances; as, of a root, of a leaf, a stalk, a flower, a cod, fruit, and the rest: and that every one of these, being from the first still the same that they shall be afterwards, do but suck in more moisture from the earth, to swel and enlarge themselvs in quantity. Or that, in the seed of the male, there is already in act the substance of flesh, of bone, of sinews, of veins, & the rest of those several similar parts, which are found in the body of an Animal; and that they are but ex∣tended to their due magnitude, by the humidity drawn from the mother; without receiving any substantial mutation, from what they were originally in the seed.

Let us then confidently conclude, that all generation is made of a fitting, but remote, homogenial compounded substance; upon which outward Agents working, in the due course of na∣ture change it into another substance, quite different from the first, and make it less homogenal then the first was. And other cir∣cumstances and agents change this second into a third; that third into a fourth; and so onwards, by successive mutations,

that still make every new thing become less homogeneal then the former was, according to the nature of heat mingling more and more different bodies together) till that substance be produced, which we consider in the period of all these muta∣tions.

And this is evident out of many experiences. As for example, in Trees, the bark, which is opposed to the North wind, is harder & thicker then the contrary side which is opposed to the south; and a great difference will appear in the grain of the wood; even so much, that skilful people will, by feeling and seeing a round piece of the wood after the Tree is fell'd, tell you in what situa∣tion it grew, and which way each side of that piece look'd. And Josephus Acosta writes of a Tree in America, that, on the one side being situated towards great hills, and on the other ex∣posed to the hot Sun; the one half of it flourishes at one time of the year, and the other half at the opposite season. and some such like may be the cause of the strange effects we somtimes see of trees, flourishing or bearing leaves at an unseasonable time of the year; as in particular, in the famous Oak in the New Forrest, and in some others in our Island: in which peradventure the Soil they grow in may do the same effect, as the winds and Sun did in the Tree that Acosta mentions. For, we daily see, how some soiles are so powerful over some kind of corn, that they will change the very nature of it; so that, you shall reap Oats or Rie after you have sown Wheat there.

Which shews evidently that, since the outward circumstances can make the parts or the whole of any substance become dif∣ferent from what they were at first; generation is not made by aggregation of like parts to presupposed like ones, nor by a specifical worker within; but, by the compounding of a se∣minary matter with the juice which accrues to it from with∣out, and with the streams of circumstant bodies; which, by an ordinary course of nature, are regularly imbibed in it by degrees, and at every degree change it into a different thing, such as is capable to result out of the present compound, (as we have said before) till it arrive to its full perfe∣ction.

Which yet is not the utmost period of natures changes; for,

from that, (for example, from corn or an Animal) it carries it on, still changing it, to be meal or a Cadaver, from thence, to be * 1.242 bread or durt, after that, to be blood or grass. And so, still turning about her wheel (which suffers nothing to remain long in the state it is in), she changes all substances from one into another: And, by reiterated revolutions, makes in time every thing of every thing. As when of mud she makes Tad∣poles, and Frogs of them, and afterwards mud again of the Frog: or when she runs a like progress, from Earth to Worms, and from them to Flies, and the like; so changing one Animal in∣to such another, as, in the next precedent step, the matter in those circumstances is capable of being changed into; or ra∣ther (to say better) must necessarily be changed into.

To confirm this by experience. I have been assured, by one who was very exact in noting such things, that he once observ'd in Spain, in the Spring season, how a stick, lying in a moist place, grew, in tract of time, to be most of it a rotten durty matter; and that, at the dirty end of the stick, there began a rude head to be form'd of it by little and little; and, after a while, some little legs began to discover themselves near this unpo∣lish'd head, which daily grew more and more distinctly shaped. And then, for a pretty while (for it was in a place where he had the conveniency to observe daily the progress of it, and no body came near to stir it in the whole course of it) he could discern where it ceas'd to be a body of a living creature, and where it began to be dead stick or dirt; all in one continuate quantity or body. But, every day the body grew longer and longer, and more legs appear'd; till at length, when he saw the Animal almost finish'd, and near separating it self from the rest of the stick; he stay'd then by it, and saw it creep away in a Caterpillar, leaving the stick and dirst, as much wanting of its first length, as the worms body took up. Perad∣venture, the greatest part of such creatures makes their way by such steps into the world. But, to be able to observe their pro∣gress thus distinctly, as this Gentleman did, happens not fre∣quently.

Therfore, to satisfie our selves herein, it were well we made our remarks in some creatures, that might be continually in our * 1.243

power to observe in them the course of nature, every day and hour. Sir John Heydon, the Lieutenant of his Majesties Ord∣nance (that generous and knowing Gentleman, and consum∣mate Souldier both in Theory and Practice) was the first that instructed me how to do this; by means of a furnace, so made as to imitate the warmth of a sitting Hen. In which you may lay several eggs to hatch; and by breaking them at several ages, you may distinctly observe every hourly mutation in them, if you please. The first will be, that on one side you shall find a great resplendent clearness in the white. After a while, a little spot of red matter, like blood, will appear in the midst of that clearness, fast'ned to the yolk: which will have a moti∣on of opening and shutting; so as somtimes you will see it, and straight again it will vanish from your sight, and indeed, at first it is so little, that you cannot see it, but by the motion of it: for, at every pulse, as it opens you may see it, and immediately again it shuts in such sort, as it is not to be discerned. From this red speck, after a while, there will stream out a number of little (almost imperceptible) red veins. At the end of some of which, in time, there will be gathered together a knot of mat∣ter, which by little and little will take the form of a head; and you will ere long begin to discern eyes and a beak in it. All this while the first read spot of blood grows bigger and solider: till at length it becomes a fleshy substance, and, by its fi∣gure may easily be discern'd to be the heart; which as yet hath no other inclosure but the substance of the egg. But, by little and little, the rest of the body of an Animal is framed, out of those red veins which stream out all about from the heart. And in process of time, that body encloses the heart within it by the chest; which grows over on both sides, and in the end meets, and closes it self fast together. After which this little creature soon fills the shell, by converting into several parts of it self all the substance of the egg. And then growing wea∣ry of so straight a habitation, it breaks prison, and comes out a perfectly formed Chicken.

In like manner, in other creatures (which in latine are cal'd Vivipera, because their young ones are quick in their mothers Womb) we have, by the relation of that learned and ex∣act

searcher into nature, Dr. Harvy; that the seed of the male, after his accoupling with the female, doth not remain in her womb, in any sensible bulk: but (as it seems) evaporates and in∣corporates it self, either into the body of the Womb, or rather into some more interior part; as, into the seminary vessels. Which, being a solid substance, much resembling the nature of the Females seed, is likely to suck up, by the mediation of the Females seed, the Male seed incorporated with it and, by incorporation, turn'd as it were into a vapour: in such sort as we have formerly explicated, how the body of a Scor∣pion or Viper draws the poyson out of the wound. And after a certain time (Dr. Harvy noted the space of six weeks or two moneths in Does or Hindes) these seeds distill again into the Womb; and by little and little clarifie in the midst, and a little red speck appears in the cencer of the bright clearness; as we said before of the egg.

But we should be too blame to leave our Reader without * 1.244 clearing that difficulty, which cannot chuse but have sprung up in his thoughts; by occasion of the relations we made, at the entrance into this point, concerning the Cat whose kitlings were half with tails and half without: and the womans daugh∣ters at Argiers, that had, as well as their mother, excresences up∣on their left thumbs, imitating another lesser thumb; and the like effects whenever they happen, which they do frequently enough.

Let him therefore remember, how we have determin'd that generation is made of the blood: which, being dispersed into all the parts of the body, to irrigate every one of them, and convey fitting spirits into them from their source or shop where they are forged; so much of it as is superabundant to the nourishing of those parts is sent back again to the heart, to recover the warmth and spirits it hath lost by so long a journey. By which perpetual course of a continued cir∣culation, 'tis evident that the blood, in running thus through all the parts of the body, must needs receive some particular concoction or impression from every one of them. And by consequence, if there be any specifical vertue in one part, which is not in another; then the blood, returning

from thence, must be endued with the vertue of that part. And the purest part of this bloud, being extracted like a quintessence out of the whole mass, is reser'd in convenient receptacles or vessels, till there be use of it, and is the matter or seed, of which a new Animal is to be made: in whom will appear the effect of all the specifical virtues drawn by the bloud in its iterated courses, by its circular motion through all the several parts of the parents body.

Whence it follows, that, if any part be wanting in the body wherof this seed is made, or be superabundant in it; whose vir∣tue is not in the rest of the body: the vertue of that part cannot be in the bloud, or will be too strong in the bloud, and by conse∣quence, it cannot be at all, or it will be too much, in the seed. And, the effect proceeding from the seed, that is, the young Ani∣mal, will come into the world savouring of that origine; unless the Mother's seed supply or temper what the Father's was de∣fective or superabundant in, or contrariwise the Father's correct the errours of the Mother's.

But peradventure, the Reader will tell us, that such a specifical * 1.245 virtue cannot be gotten by concoction of the blood, or by any petended impression in it; unless some little particles of the nourished part remain in the blood, and return back with it; according to that maxim of Geber, Quod non ingreditur non im∣mutat, no body can change another unless it enter into it, and, mixing it self with it, become one with it. And that so in ef∣fect, by this explication, we fall back into the opinion which we rejected.

To this I answer, that the difference is very great between that opinion and ours; as will appear evidently, if you observe the two following assertions of theirs. First they affirm, that a living creature is made m••erly by the assembling together of similar parts, which were hidden in those bodies from whence they are extracted in generation: wheras we say that bloud, coming to a part to irrigate it, is, by its passage through it and some little stay in it, and by its frequent returns thither, at length transmuted into the nature of that part; and therby the speci∣fical vertues of every part grow greater, and are more diffused and extended.

Secondly, they say, that the Embryon is actually formed in the seed; though in such little parts as it cannot be discerned, till each part have enlarged and increased it self, by drawing to it from the circumstant bodies more substance of their own na∣ture. But we say, that there is one Homogenal substance made of the blood, which hath been in all parts of the body; and this is the seed: which contains not in it any figure of the Animal from which it is refined, or of the Animal into which it hath a capacity to be turned (by the addition of other sub∣stances); though it have in it the vertues of all the parts it hath often run through.

By which term of specifike vertues, I hope, we have said enough in sundry places of this discourse, to keep men from concei∣ving that we mean any such inconceivable quality, as mo∣dern Philosophers too frequently talk of; when they know not what they say or think, nor can give any account of. But that it is such degrees and numbers of rare and dense parts ming∣led together, as constitute a mixed body of such a temper and nature: which degrees and proportions of rare and dense parts, and their mixture together, and incorporating into one Homo∣geneal substance, is the effect resulting from the operations of the exteriour agent, that cuts, imbibes, kneads, and boyls it to such a temper. Which exteriour agent, in this case, is each several part of the Animals body, that this juice or blood runs through; and that hath a particular temper belonging to it, resulting out of such a proportion of rare and dense parts, as we have even now spoken of; and can no more be with-held from communicating its temper to the bloud, that first soaks in∣to it and soon after drains away again from it (according as other succeeding parts of bloud drive it on): then a mineral channel can chuse but communicate its vertue to a stream of water that runs through it, and is continually grating off some of the substance of the Mineral earth, and dissolving it into it self.

But, to go on with our intended discourse. The seed, thus im∣bued * 1.246 with the specifical vertues of all the several parts of the parents body, meeting in a fit receptacle the other parents seed, and being there duly concocted, becomes first a heart. Which

heart, in this tender beginning of a new Animal, contains the several virtues of all the parts, that afterwards will grow out of it and be in the future Animal: in the same manner as the heart of a complete Animal: contains in it the specificke virtues of all the several parts of its own body, by reason of the bloods conti∣nual resorting to it in a circle from all parts of its body, and its being nourished by that juice, to supply the continual consump∣tion which the extreme heat of it must needs continually oc∣casion in its own substance; wherby the heart becoms in a manner the Compendium or abridgment of the whole Ani∣mal.

Now, this heart, in the growing Embryon, being of the nature of fire; as, on the one side, it streams out its hot parts; so, on the other, it sucks oyl or fewel to nourish it self out of the adjacent moist parts: which matter aggregated to it being sent abroad, together with the other hot parts that steam from it; both of them together stay and settle, as soon as they are out of the reach of that violent heat, that would not permit them to thicken or rest. And there they grow into such a substance, as is capable to be made of such a mixture; and are linked to the heart by some of those strings that steam out from it (for those steams likewise harden, as we shew'd more parti∣cularly, when we discours'd of the tender stalks of plants): and in a word, this becoms some other part of the Ani∣mal. Which thus encreases by order, one part being made after another; till the whole living creature be completely framed.

So that now you see, how mainly their opinion differs from ours: since, they say that there is actually in the seed a complete living creature; for, what else is a living creature, but bones in such parts, nerves in such others, bloud and humours con∣tain'd in such and such places, all as in a living creature? All which they say. But, we make the seed to be nothing else but one mixed body, of one homogeneal nature throughout; consisting of such a multiplicity of rare and dense parts, so ballan∣ced and proportioned in number and magnitude of those parts, which are evenly shuffled and alike mingled in every little parcel of the whole substance: in such sort, that the operation

of nature upon this seed, may, in a long time and with a due process, bring out such figures, situation, and qualities (as flui∣dity, consisence, driness, and the like), which, by much mixstion and consequent alteration, may in the end become such as con∣stitute a living creature of such a kind. And thus it appears that, although other substances and liquors and steams are, from time to time, mingled with the seed, and then with the heart, and afterwards with the other parts, as they grow on and en∣crease; yet the main virtue of the ensuing Animal is first in the seed, and afterwards in the heart.

Whence the reason is evident, why both defects and excre∣scences pass somtimes from the parents to the children; to wit, when nothing supplies the defect or corrects the exorbitancy. Rather, after this which we have said, the difficulty will appear greater, in that such accidents are not always hereditary from the parents; but happen only now and then, some rare times. But, the same grounds we have laid wil likewise solve this objecti∣on. For, seeing that the heart of the Animal, from whence the seed receives its proper nature (as we have declared) is impregnated with the specifick virtue of each several part of the body; it can∣not be doubted but that the heart will supply for any defect hapned in another part, after it hath been imbued with that virtue, and is grown to a firmness and vigorous consistence, with that virtue moulded and deeply imbibed into the very substance of it. And although the heart should be tincted, from its first origine, with an undue virtue from some part (as it seems to have been in the mother of those daughters that had two thumbs upon one hand); yet it is not necessary that all the off-spring of that parent should be formed after that model; for, the other partners seed may be more efficacious and predominant in the geniture, over the faulty seed of the other parent; and then it will supply for and correct the others deviation from the gene∣ral rule of nature. Which seems to be the cause of that wo∣mans male children; for, in them the fathers seed being strongest, all their fingers imitated the regularity of their Fathers: wher∣as the daughters (whose sex implies that the fathers seed was less active) carried upon some of theirs the resemblance of their mo∣thers irregularity.

And, in confirmation of this doctrine, we daily see, that the Children of Parents who have any of their noble parts much and long distempred, wherby there must be a great distemper in the bloud (which is made and concocted by their assistance), seldom fail of having strong inclinations to the distempers and diseases that either of their parents were violently subject to. Scarce any Father or Mother dyes of the Consumption of the Lungs, but their children inherit that disease in some measure: the like is of the Stone; the like of the Gout, the like of diseases of the brain, and of sundry others; when they infested the pa∣rents with any notable eminency. For the bloud, coming con∣tinually to the heart from such ill-affected parts, by its circula∣tion through the whole body, must needs in process of time al∣ter and change the temper of the heart; and then both the heart gives a tainted impression to the blood that must be boyl'd into seed, and the parts themselvs communicate their debilites and distempers to it: so that it is no wonder, if the seed partake of such depraved qualities; since it is a maxime among Physici∣ans, that subsequent concoctions can never amend or repair the faults of the precedent ones.

Having waded thus far into this matter, and all experience agreeing that the whole Animal is not formed at once; I con∣ceive * 1.247 there can be no great difficulty in determining what part of it is first generated: which we have already said to be the heart but peradventure the Reader may expect some more particular and immediate proof of it. 'Tis evident, that all the motions and changes we have observ'd in the Egg and in the Doe proceed from heat: and tis as certain, that heat is greatest in the centre of it; from whence it disperses it self to less and less. It must then necessarily follow, that the part in which heat most a∣bounds, and which is the interiour fountain of it from whence (as from a stock of their own) all the other parts derive theirs, must be formed first; and the others successively after it: ac∣cording as they partake more or less of this heat; which is the Architect that moulds and frames them all. Undoubtedly this can be none other but the heart: whose motion and manner of working evidently appears in the twinckling of the first red spot (which is the first change) in the Egg, and in the

first matter of other living creatures: Yet I do not intend to say, that the heart is perfectly framed, and compleatly made up, with all its parts and instruments; before any other part be begun to be made: but only the most vertuous part; and, as it were, the marrow of it, which servs as a shop or hot forge to mold spirits in; from whence they are dispers'd abroad to form and nourish other parts that stand in need of them to that effect.

The shootings or little red strings that stream out from it must surely be arteries: through which the bloud issuing from the heart, and there made and imbued with the nature of the seed, runs; till encountering with fit matter, it engrosses it self into brain, liver, lights, &c. From the brain chiefly grows the marrow and, by consequent, the bones containing it, (which seem to be originally but the outward part of the mar∣row, baked and hardned into a strong crust by the great heat that is kept in): as also the sinews, which are the next princi∣pal bodies of strength, after the bones. The marrow being very hot dries the bones; and yet with its actual moisture it hu∣mects and nourishes them too, in some sort. The spirits that are sent from the brain do the like to the sinews. And lastly, the arteries and veins, by their bloud, cherish and bedew the flesh. And thus the whole living creature is begun, framed and made up.

CHAP. XXV. How a Plant or Animal c••mes to that figure it hath.

BUt, before we go any further, and search into the operations * 1.248 of this Animal, a wonderful effect calls our consideration to it: which is, how a Plant or Animal comes by the figure it hath, both in the whole and in every part of it? Aristotle, after he had beaten his thoughts as far as he could upon this question, pronounced that this effect could not possibly be wrought by the virtue of the first qualities; but that it sprung from a more divine origine: And most of the contemplatours of Na∣ture, since him, seem to agree, that no cause can be render'd of it; but that it is to be refer'd merely to the specifical

nature of the thing. Neither do we intend to derogate from either of these causes: since, both Divine Providence is emi∣nently shown, in contriving all circumstances necessary for this work; and likewise, the first temperament that is in the seed must needs be the principal immediate cause of this admirable effect.

This latter then being supposed; our labour and endeavour will be to unfold (as far as so weak and dim eyes can reach) the excellency and exactness of Gods Providence; which cannot be enough adored, when it is reflected on and mark'd in the apt laying of adequate causes to produce such a figure, out of such a mixture first laid. From them, so artificially ran∣ged, we shall see this miracle of nature to proceed; and not from an immediate working of God or nature, without conve∣nient and ordinary instruments to mediate and effect this con∣figuration, through the force and virtue of their own particu∣lar natures. Such a necessity to interest the chief workman at every turn, in particular effects, would argue him of want of skill and providence, in the first laying of the foundations of his designed Machine. He were an improvident Clockmaker, that should have cast his work so, as, when it were wound up and going, it would require the Masters hand at every hour, to make the Hammer strike upon the Bell. Let us not then, too familiarly and irreverently, ingage the Almighty Architect's immediate handy-work in every particular effect of nature; Tali non est dignus vindice nodu••.

But, let us take principles within our own kenning; and con∣sider, how a body hath, of its own nature, three dimensions, (as * 1.249 Mathematicians use to demonstrate): and that the variety we see of figures in bodies proceeds out of the defect of some of these dimensions, in proportion to the rest. As for example, that a thing be in the form of a Square Tablet; is, for that the cause, which gave it length and breadth, could not also give it thickness in the same proportion: for, had it been able to give profundity as well as the other two, it had made a Cube instead of a Tablet. In like manner, the former of a la∣mine, or very long square, is occasion'd by some accident which hinders the cause from giving breadth and thickness propor∣tionable

to the length. And so, other figures are made, by rea∣son that their causes are some ways bound to give more of some dimension to one part then another.

As for example, when water falls out of the skie, it hath all the little corners or extancies of its body grated off by the air, as it rolls and tumbles down in it; so that it becomes round: and continues in that form, till, setling on some flat body (as Grass or a Leaf), it receives a little plainness, to the proportion of his weight mastering the continuity of it. And therfore, if the drop be great upon that plain body, it seems to be half a Sphere, or some less portion of one: but, if it be a little drop, then the flat part of it (which is that next the grass) is very little and undiscernable, because it hath not weight enough to press it much and spread it broad upon the grass, and so the whole seems in a manner to be a Sphere. But, if the extern causes had press'd upon this drop on∣ly broadways and thick ways (as when a Turner makes a round Pillar, of a square one) then it would have proved a Cylinder; nothing working upon it to grate off any of its length, but only the corners of the breadth and thickness of it.

And thus you see, how the fundamental figures (upon which all the rest are grounded) are contrived by nature: not by the work of any particular Agent that immediately Imprints a de∣terminate figure into a particular body, as though it wrought it there at once, according to a foreconceiv'd design or intel∣ligent aim of producing such a figure in such a body; but by the concurrence of several accidental causes, that all joyn in bringing the body, they file and work upon into such a shape.

Only, we had like to have forgotten the reason and cause of the concave figure in some parts of Plants: which, in the ordi∣nary course of nature, we shall find to grow from hence, That a round outside being filled with some liquor, which makes it grow higher and higher, it happens that the succeeding cau∣ses contract this liquor and harden the outside; and then of necessity there must be a hollow Cylinder remaining, in lieu of the juice which before fill'd it. As we see every day in corn,

and in Reeds, and in Canes, and in the stalks of many herbs: which, whilst they are tender and in their first growth, are full of juice; and become afterwards hallow and dry.

But, because this discourse may peradventure seem too much in common: it will not be amiss to apply it to some particulars * 1.250 that seem very strange. And first, let us examine how the rock∣ing of concrete juices (which seems to be such an admirable mystery of Nature) is performed. Allom falls down in lumps, Saltpeter in long icicles, and common Salt in squares: and this, not once or somtimes, now or then, but always constantly in the same order.

The reason of these effects will easily be deduced out of what we have said. For, if all three be dissolv'd in the same water, Allom, being the grossest, falls first, and fastest, and, being of an unctious nature, the first part which falls doth not harden till the second comes to it; wherby this second sticks to the first and crushes it down, and this is serv'd in the same manner by the third: and so it goes on, one part squeezing another▪ till what is undermost grow hard enough to resist the weight of new fal∣ling parts; or rather, till no more fall; but the liquor they were dissolv'd in is deliver'd of them all, and then they harden in that figure they were compress'd into.

As for Salt, which descends in the second place; that swims first upon the water, and there gets its figure, which must be equally long and broad, because the water is indif∣ferent to those two positions: but its thickness is not equal to its other two dimensions, by reason that, before it can at∣tain to that thickness, it grows too heavy to swim any lon∣ger, and, after it is encreas'd to a certain bulk, the weight of it carries it down to the bottom of the water, and conse∣quently it can encrease no more; for, it encreases by the joyning of little parts to it, as it swims on the top of the water.

The Saltpeter falls last; which being more difficult to be figured then the other two, because it is more dry then either of them, (as consisting chiefly of earthy and of fiery parts), is not equally encreased, neither in all three, nor in two dimensions, but hath its length exceeding both its breadth and thickness:

and its lightness makes it fall last, because it requires least wa∣ter to sustain it.

To give the causes of the figures of divers mixts, and parti∣cularly of some precious stones (which seems to be cast by Na∣ture in exactest moulds), would oblige us to enter into the particular manner of their generation: which were exceeding hard, if not impossible, for us to do, by reason that Authors have not left us the circumstances, upon which we might groūd our judgment concerning them, so particularly described as were necessary; nor our selves have met with the commodity of making such experiences, and of searching so into their beds as were requisite, to determine solidly the reasons of them. And indeed, I conceive, that oftentimes the relations which o∣thers have recorded of their generation would rather mislead then assist us: since it is very familiar in many men, to mag∣nifie the exactness of Nature, in framing effects by phansie to themselvs; when, to make their Wonder appear more just, they will not fail to set off their story with all advantageous circum∣stances, and help out what wants a little or comes but near the mark.

But, to come closer to our purpose; that is, to the figures of living things. We see that the roots in the earth are all of them * 1.251 figured almost in the same fashion: for the heat residing in the midd'st of them pushes every way, and therupon, some of them become round, but others more long then round; accor∣ding to the temper of the ground, or the season of the year, or the weather that happens: and this, not onely in divers kinds of Roots, but even in several of the same kind. That part of the plant which mounts upwards, for the most part, round and long; the cause wherof is evident. For, the juice which is in the middle of it working upwards (because the hardness of the bark will not let it out at the sides), and coming in more and more abundance (for the reasons we have above deliver'd), encreases that part equally every way but upwards; and therfore it must be equally thick and broad, and consequently round: but the length will exceed either of the other dimensions; because the juice is driven up with a greater force, and in more quantity then it is to the sides. Yet

the broadness and thickness are not so exactly uniform, but that they exceed a little more at the bottom then at the top, which is occasion'd, partly by the contracting of juice in∣to a narrower circuit, the further it is from the source; and partly by reason of the Branches, which, shooting forth, convey away a great part of the Juice from the main stock.

Now, if we consider the matter well, we shall find, that * 1.252 what is done in the whole tree, the very same is likewise done in every little leaf of it. For, a leaf consists of little branches shooting out from one greater branch, which is in the middle; and again, other less branches are derived from those second branches: and so still lesser and lesser, till they weave them∣selvs into a close work, as thick as that which we see women use to fill up with Silk or Crewel, when in Tentwork they em∣broyder leafs or flowers upon Canvas. And this again is co∣ver'd and, as it were, glew'd over, by the humour which, stick∣ing to these little thrids, stops up every little vacuity, and by the air is hardened into such a skin as we see a leaf consists of.

And thus it appears, how an account may be given of the figure of the leafs, as well as of the figure of the main body of the whole tree: the little branches of the leaf being propor∣tionate in figure to the branches of the tree itself (so that each leaf seems to be the Tree in little), and the figure of the leaf depending of the course of these little branches; so that, if the greatest branch of the Tree be much longer then the others, the leaf will be a long one, but if the lesser branches spread broad∣ways, the leaf will likewise be a broad one; so far, as even to be notch'd at the outsides, round about it, in great or little notches; according to the proportion of the Trees Branches. These Leafs, when they first break out, are foulded inwards; in such sort as the smalness and roundness of the passage in the wood, through which they issue, constrains them to be: where nevertheless the driness of their parts keep them asunder; as that one leaf doth not incorporate it self with another. But, so soon as they feel the heat of the Sun (after they are broken out into liberty), their tender branches by little and little

grow more straight: the concave parts of them drawing more towards the Sun, because he extracts and sucks their moy∣sture from their hinder parts into their former, that are more exposed to his beams; and thereby the hinder parts are con∣tracted and grow shorter, and those before grow longer. Which, if it be in excess, makes the leaf become crooked the contrary way; as we see in divers flowers, and in sundry leaves during the Summers heat: witness, the Ivie, Roses full blown. Tulips, and all flowers in form of Bells; and indeed all kinds of flow∣ers whatever, when the Sun hath wrought upon them to that degree we speak of, and that their joyning to their stalk, and the next parts thereto allow them scope, to obey the impulse of those outward causes. And, when any do vary from this rule we shall as plainly see other manifest causes pro∣ducing those different effects, as now we do those working in this manner.

As for Fruits, though we see that, when they grow at liberty upon the Tree, they seem to have a particular figure allotted them by nature; yet in truth, it is the order'd series of natural causes, and not an intrinsecal formative virtue which breeds this effect: as is evident, by the great power which art hath to change their figures at pleasure, wherof you may see examples enough in Campanella; and every curious Gardener can furnish you with store.

Out of these and such like principles, a man that would make * 1.253 it his study (with less trouble of tediousness then that patient contemplator of one of natures little works, the Bees; whom we mention'd a while agone) might without all doubt, trace the causes in the growing of an Embryon; till he discover'd the reason of every bones figure, of every notable hole or passage in them, of the Ligaments by which they are tied together, of the membranes that cover them; and of all the other parts of the body. How, out of a first Masse, that was soft and had no such parts distinguishable in it, every one of them came to be formed; by contracting that Masse in one place, by dilating it in another, by moistning it in a third, by drying it here, hard'ning it there;

—Ut his exordia primis, Omnia, & ipse tener hominis concreverit orbis.

till in the end this admirable machine and frame of mans body was composed and fashioned up, by such little and almost insen∣sible steps and degres. Which, when it is look'd upon in bulk and entirely-formed, seems impossible to have been made, and sprung merely out of these principles; without an Intelligence immediately working and moulding it at every turn, from the beginning to the end.

But withall, we cannot chuse but break out into an extasie of admiration and hymns of praise (as great Galen did upon the like occasion), when we reverently consider the infinite Wise∣dome and deep far-looking Providence of the all-seeing Cre∣atour and Orderer of the World; in so punctually adopting such a multitude and swarm of causes to produce, by so long a pro∣gress, so wonderful an effect: in the whole course of which, if any one, the very least of them all, went never so little awry, the whole fabrick would be discomposed and changed from the na∣ture it is design'd to.

Out of our short survey of which (answerable to our weak talents and slender experience) I perswade mv self it appears * 1.254 evident enough, that, to effect this work of generation, there needs not be supposed a forming virtue, or Vis formatrix, of an anknown power and operation; as those that consider things suddenly and but in gross use to put. Yet, in discourse, for conveniency and shortness of expression, we shall not quite banish that term from all commerce with us; so that what we mean by it be rightly understood: which is, the complex, assemblement, or chain of all the causes, that concur to produce this effect; as they are set on foot to this end by the great Archi∣tect and Moderatour of them, God Almighty, whose instrument Nature is: that is, the same thing, or rather the same things, so order'd as we have declared; but express'd and compriz'd under another name,

CHAP. XXVI. How motion begins in Living Creatures: And of the motion of the Heart; circulation of the Bloud; Nutrition, Augmentation, and Cor∣ruption or Death.

BUt we must not take our leave of this subject, til we have ex∣amin'd, * 1.255 how motion begins in living things; as well Plants as Sensative creatures. We can readily pitch upon the part we are to make our observations in, for retriving the ori∣gine of this primary motion: for, having concluded, that the roots of Plants, and the hearts of Animals, are the parts of them which are first made, and from which the forming virtue is de∣rived to all the rest; it were unreasonable to seek for their first motion any where else.

But, in what manner, and by what means doth it begin there? For roots, the difficulty is not great, for, the moysture of the earth pressing upon the seed, and soaking into it, the hot parts of it, which were imprison'd in cold and dry ones, are therby stir'd up and set on work; then they, mingling them∣selves with that moysture, ferment and distend the whole seed, til, making it open and break the skin, more juice comes in: which imcorporating it self with the heat, those hot and now moyst parts will not be contain'd in so narrow a room as at the first; but, strugling to get out on all sides, and striving to enlarge themselvs, they thrust forth little parts. Which, if they stay in the earth, grow white, and make the root; but those which ascend and make their way in∣to the air, being less compressed and more full of heat and moysture, turn green: and, as fast as they grow up, new moysture coming to the root is sent up through the pores of it; and this fails not, till the heat of the root it self fails. For, it being the nature of heat to rarifie and elevate, there must of necessity be caus'd in the earth a kind of suck∣ing in of moysture into the root from the next parts to it, to fill those capacities which the dilating heat hath made, that

else would be empty; and to supply the rooms of those which the heat continually sends upwards: for, the moysture of the root hath a continuity with that in the earth, and therfore they adhere together (as in a Pump, or rather as in filtration) and follow one another, when any of them are in motion; and still the next must needs come in and fill the room, where it finds an empty space immediate to it. The like of which happens to the Air when we breath: for, our lungs be∣ing like a Bladder, when we open them the air must needs come in, to fill that capacity which else would be empty; and when we shut them again, as in a pair of Bellows, we put it out.

This may suffice, concerning the primary motion of roots: * 1.256 but in that of the heart, we shall find the matter not altoge∣ther so plain, Monsieur des Cartes, following herein the steps of the learned and ingenuous Dr. Harvey, who hath invented and teaches that curious and excellent Doctrine of the Cerculation of the Bloud, (as indeed, what secret of nature can be hidden from so sharp a wit, when he applyes himself to penetrate in∣to the bottome of it), explicates the matter much after this sort. That the heart, within the substance of it, is like a hollow Cavern in whose bottome were an hot stone, on which should drop as much liquor as the fiery stone could blow into smoke; and this smoke or steam should be more then the Cave could contain, wherfore it must break out: which to do, it pres∣ses on all sides, to get an issue or door to let it out. It finds of two sorts, but only one kind of them will serve it for this pur∣pose; for the one sort of these doors opens inwards, the other outwards: which is the cause that, the more it strives to get out, the faster it shuts the doors of the first kind; but, by the same means, it beats back the other doors, and so gets out.

Now, when it is gone quite out of this Cavern, and conse∣quently leaves it to its natural disposition; whereas before it violently stretched it out, and, by doing so, kept close the doors that open inwards: then, all the parts of it begin to slacken, and those Doors give way to new liquor to drop in anew; which the heat in the bottome of the heart rarifies again in∣into

smoke, as before. And thus he conceives the motion of the heart to be made; taking the substance of it to be (as I may say) like to limber Leather, which, upon the feeling of it with bloud and steam, opens and dilates it self; and at the going of it out, it shrinks together like a blad∣der.

But, I doubt this Explication will not go through the diffi∣culty. * 1.257 For first, both Galen and Dr. Harvey shew, that, as soon as the bloud is come into the heart, it contracts it self; which agrees not with Monsir des Cartes his suppo∣sition: for, in his doctrine, there appears no cause why it should contract it self, when it is full; but contrariwise, it should go on dilating it self; till enough of the bloud which drops into the heart were converted into steam, to force the doors open, that so it may gain an issue thence, and a passage into the body.

Next, Monsir des Cartes supposes that the substance of the heart is like a bladder, which hath no motion of it self; but opens and shuts, according as what is within it stretches it out, or permits it to shrink and fall together again. Wheras Dr. Harvey proves that, when it is full, it compresses itself by a quick and strong motion, to expel that which is in it; and that, when it is empty, it returns to its natural dilatation, figure, and situation; by the ceasing of that agents working, which caused its motion. Wherby it ap∣pears to be of such a fibrous substance, as hath a proper motion of its own.

Thirdly, I see not how this motion can be proportional. For, the heart must needs open and be dilated, much faster then it can be shut and shrunk together; there being no cause put to shut and bring it to its utmost period of shrinking, other then the going out of the vapour, wherby it becomes empty: which vapour, not being forced by any thing but its own inclination, may peradventure, at first when there is abundance of it, swell and stretch the heart forcibly out; but, after the first impulse and breach of some part of it out of the Cavern that enclo∣sed it, there is nothing to drive out the rest, which must therfore steam very leasurely out.

Fourthly, what should hinder the blood from coming in before the heart be quite-empty and shrunk to its lowest pitch? For as soon as the vapour yeelds within, new blood may fall in from without; and so keep the heart continually di∣lated, without ever suffering it to be perfectly and compleat∣ly shut.

Fifthly, the heart of a Viper, layd upon a plate in a warm place, will beat four and twenty houres, and much longer, if it be carefully taken out of its body, and the weather warm and moyst: and it is clear, that this is without succession of blood to cause the pulses of it. Likewise, the several members of living creatures will stir for sometime, after they are parted from their bodies: and in them we can suspect no such cause of motion.

Sixthly, Mounsir des Cartes his opinion, the heart should be hardest when it is fullest; and the eruption of the steam out of it should be strongest at the beginning; wheras experience shews, that it is softest when it is at the point of being full, and hardest when it is at the point of being empty; and the motion strongest towards the end.

Seventhly, in Mounsir des Cartes his way, there is no agent or force strong enough to make blood gush out of the heart. For, if it be the steam only that opens the doors, nothing but it will go out, and the blood will still remain behind; since it lies lower then the steam, and further from the issue that lets it out: but Dr. Harvey findes by experience (and teaches how to make this experience) that, when a wound is made in the heart, blood will gush out by spurts at every shoot∣ing of the heart.

And lastly, if Mounsir des Cartes, his supposition were true, the arteries would receive nothing but steams; wheras it is evi∣dent, that the chief filler of them is blood.

Therfore we must enquire after another cause of this prima∣ry * 1.258 motion of a sensitive creature, in the beatings of its heart. Wherin we shall not be obliged to look far: for seeing we find this motion and these pulsations in the heart, when it is sepa∣rated from the body; we may boldly and safely conclude, that it must of necessity be caused by somthing that is

within the heart it self. And what can that be else, but heat or spirits imprison'd in a tough viscous bloud: which it cannot so presently break through to get out; and yet can stir within it, and lift it up?

The like of which motion may be observ'd, in the heaving up and sinking down again of lose mould thrown into a pit, intoe which much ordure hath been emptied. The same cause, of h at in the earth, makes mountains and sands to be cast up in the very sea. So, in frying, when the pan is full of meat, the bub∣bles rise and fall at the edges. Treacle, and such strong com∣pounded substances, whiles they ferment, lift themselvs up and sink down again; after the same manner as the Vipers heart doth: as also do the bubbles of Barm, and most of Wine. And short ends of Lute strings, baked in a juicy pie, will, at the open∣ing of it, move in such sort, as they who are ignorant of the feat will think there are Magots in it: and a hot loaf, in which quick∣silver is enclosed, will not only move thus, but will also leap about, and skip from one place to another; like the head or limb of an Animal (very full of spirits) newly cut off from its whole body.

And that this is the true cause of the hearts motion, appears evidently. First, because this virtue of moving is in every part of the heart; as you will plainly see, if you cut out into several pieces a heart, that conservs its motion long after it is out of the Animals belly: for every piece will move; as Dr. Harvey assures us by experience, and I my self have often seen, upon oc∣casion of making the great antidote, in which Vipers hearts is a principal ingredient. Secondly, the same is seen in the auri∣cles and the rest of the heart; whose motions are several; though so near together, that they can hardly be distinguished. Thirdly, Dr. Harvey seems to affirm, that the blood which is in the ears of the heart, hath such a motion of it self, precedent to the motion of the ears it is in: and that this virtue remains in it, for a little space after the ears are dead. Fourthly, in touching a heart, which had newly left moving, with his finger weted with warm spittle, it began to move again; as testifying that heat and moisture made this moti∣on. Fifthly, if you touch the Vipers heart over with vineger,

with spirit of wine, with sharp white-wine, or with any piercing liquor; it presently dyes: for the acuteness of such substances pierces through the viscous bloud, and makes way for the heat to get out.

But, this first mover of an Animal must have somthing from without to stir it up; else, the heat would lie in it, as if it were dead, and in time would become absolutely so. In Eggs you see this exteriour mover, in the warmth of the Hens hatching them: And in Embryons, it is the warmth of the mothers womb. But when in either of them, the heart is completely form'd and enclosed in the breast, much heat is likewise enclosed there, in all the parts near about the heart; partly made by the heart it self, and partly caused by the outward heat, which helped also to make that in the heart: and then, although the warmth of the hen or of the mothers womb forsake the heart; yet this stirs up the native heat within the heart and keeps it in motion, and makes it feed still upon new fewel, as fast as that which it works upon decayes.

But, to express more particularly how this motion is effected, * 1.259 We are to note, that the heart hath in its ventrickles three sorts of fibers. The first go long ways (or are straight ones) on the sides of the ventricles, from the thick basis of the heart, to∣wards the little tip or cone of it: the second go cross, or round∣ways, about the ventricles within the heart; and the third, are transversal or thwart ones. Next, we are to remember, that the heart is fix'd to the body by its base; and hangs loose at the cone. Now then, the fibers being of the nature of such things as will swell and grow thicker by being moisten'd; and conse∣quently shrink up in length and grow shorter, in proportion to their swelling thicker (as you may observe in a loose-wrought hempen rope): it must of necessity follow, that, when the bloud falls into the heart (which is of a kind of spungy substance); the fibers, being therwith moist'ned, will presently swell in round∣ness and shrink in length.

Next, we are to note, that there is a double motion in the heart: the one of opening, which is call'd Diastole; the other of shutting, which is term'd Systole. And although Dr. Har∣vey seems to allow the opening of the heart to be no motion;

but rather a relenting from motion; nevertheless (me thinks) 'tis manifest, that it is not only a compleat motion, but, in a manner, the greater motion of the two, though indeed the less sensible, because it is perform'd by little and little: for in it the heart is drawn by violence from its natural position, which must be (as it is of all heavy things) that by which it approaches most to the center of gravity; and such a position we see it gains by the shutting of it.

Now, to declare how both these motions are effected, we are to consider how, at the end of the Systole, the heart is voided and cleansed of all the bloud that was in it; whence it follows, that the weight of the bloud which is in the auricles, pressing upon the valvulas or doors that open inwards, makes its way by little and little into the ventricles of the heart: where it must neces∣sarily swell the fibers, and they being swelled must needs draw the heart into a roundish and capacious figure; which the more it is done, the more blood comes in, and with greater violence. The following effect of which must be, that the weight of the blood, joyn'd to the weight of the heart it self and particular∣ly of the conus or tip (which is more solid and heavy in pro∣portion to its quantitity, then the rest of the heart,) must neces∣sarily set the heart into the natural motion of descending ac∣cording to its gravity; which, consequently, is perform'd by a lively jerk, wherby it comes to pass, that the tip of our heart as it were springs up towards our breast; & the bloud is spurted out by other valvulae (that open outwards) which are aptly disposed to be open'd upon such a motion, and convey it to the arteries.

In the course of which motion, we may note, how the figure of our heart contributes to its springing up towards our breast; for, the line of distance between the basis and the tip being longer on that side towards the back, then on the other towards the breast; it must happen that, when the heart shuts and straightens it self, and thereby extends it self to its length, the tip will but out forwards towards the breast.

Against this doctrine, of the motion, and of the Systole and * 1.260 Diastole of the heart, it may be objected, that beasts hearts do not hang like a mans heart, straight downwards, but rather horizantally; and therfore this motion of gravity cannot have

place in them: nevertheless, we are sure they beat, and open and shut regularly. Besides, if there were no other cause, but this of gravity, for the motion of a mans heart; it would follow that one, who were set upon his head or hung by his heels, could not have the motion of his heart: which posture nevertheless, we see men remain in for a pretty while, without any extreme prejudice.

But these difficulties are easily answer'd. For, first, whether beasts hearts lie directly horizontally, or whether the basis be fast'ned somwhat higher then the tip reaches, and so makes their heart hang inclining downwards; still the motion of gravity hath its effect in them. As we may perceive in the heart of a viper lying upon a plate, and in any other thing that of it self swells up, and straight again shrinks down: in which we cannot doubt, but that the gravity, fighting against the heat, makes the elevated parts fall, as the heat makes them rise.

And as for the latter, 'tis evident that men cannot stay long in that posture, without violent accidents; and, in any little while, we see, the bloud comes into their face and other parts, which naturally are situated higher, but by this position become low∣er then the heart: and much time is not required, to have them quite disorder'd and suffocated; the bloud passing through the heart with too much quickness, and not receiving due con∣coction there, and falling thence in too great abundance into places that cannot with conveniency entertain it.

But you will insist, and ask, Whether in that posture the heart moves or no; and how? And, to speak by guesse in a thing I have not yet made experiences enough to be throughly inform'd in; I conceive, without any great scruple, that it doth move: And that it happens thus, That the heart, hanging some∣what loose, must needs tumble over, and the tip of it lean down∣wards some way or other; and so lie in part like the heart of a beast, though not so conveniently accommodated: and then the heat, which makes the viscous bloud that is in the substance of the heart to ferment, wil not fail of raising it up; wherupon, the weight of that side of the heart that is lifted up will presently press it down. And thus, by the alternative operations of these

causes, the heart will be made to open and shut it self; as much as is necessary for admitting and thrusting out that little and disorderly coming bloud, which makes its course through it, for that little space wherin the man continues in that posi∣tion.

Now, from these effects wrought in the heart by the moist∣ning of the fibers, two other effects proceed. One is, that * 1.261 the bloud is push'd out of every corner of the heart with an im∣petuousness or velocity: The other is, that by this notion the spirits, which are in the ventricles of the heart and in the bloud that is even then heated there, are more and deeper press'd into the substance of the heart; so that you see the heart imbibes fresh vigour, and is strengthened with new spirits, whiles it seems to reject that which should strengthen it.

Again, two other effects follow this violent ejection of the bloud out of the heart. One is, that, for the present, the heart is entirely cleans'd of all remainders of bloud; none being per∣mitted to fall back, to annoy it. The other is, that the heart find∣ing it self dry, the fibers relent presently into their natural po∣sition and extension, and the valvulae that open inwards fall flat to the sides of the ventricles; and consequently new bloud drops in. So that, in conclusion, we see, the motion of the heart depends originally of its fibers irrigated by the blood; and not from the force of the vapour, as Monsieur des Cartes sup∣poses.

This motion of the heart drives the blood (which is warm'd and spiritualiz'd, by being boyl'd in this furnace) through due passages into the arteries, whence it runs into the veins: and is a main cause of making and nourishing other parts; as the Liver, the Lungs, the Brains, and whatsoever else depends of those veins and arteries through which the bloud goes. Which being ever freshly heated, and receiving the tincture of the hearts nature, by passing through the heart; wherever it stayes and curdles, it grows into a substance, of a nature conform∣able to the heart; though every one of such substances be of exceeding different conditions in themselves; the very gros∣sest excrements not being excluded from some participation of that nature.

But, if you desire to follow the blood all along, every step in its progress from the heart round about the body, till it return back again to its center; Dr. Harvey, who most acutely teaches this doctrine, must be your guide. He will shew you how it issues from the heart by the Arteries; from whence it goes on warming the flesh til it arrive to some of the extremities of the body: and against it is grown so cool (by long absence from the fountain of its heart, and by evaporating its own stock of spirits without any new supply) that it hath need of being warmed a∣new, it findes it self return'd back again to the Heart, and is there heated again; which return is made by the Veins, as its go∣ing forwards is perform'd only by the Arteries.

And, were it not for this continual circulation of the blood, and this new heating it in its proper caldron, the Heart; it could not be avoided but that the extreme parts of the body would soon grow cold and die. For, flesh being of it self of a cold na∣ture (as is apparent in dead flesh), and being kept warm meerly by the blood that bedews it; and the bloud likewise being of a nature that soon grows cold and congeals, unless it be pre∣serv'd in due temper by actual heat working upon it: how can we imagine that they two singly, without any other assistance, should keep one another warm (especially in those parts that are far distant from the heart) by only being together? Surely, we must allow the blood (which is a substance fit for motion) to have recourse back to the heart (where only it can be sup∣ply'd with new heat and spirits); and from thence be driven out again by its pulses or strokes, which are its shuttings. And, as fast as it flies out, (like a reeking thick steam, which rises from perfumed water falling upon a heated pan), that which is next before it must flie yet further on, to make way for it; and, newt arterial blood stil issuing forth at every pulse, it must still drive on what issued thence the last precedent pulse, and that part must press on what is next before it. And thus it fares with the whole mass of blood; which, having no other course but in the body, must at length run round, and by new vessels (which are the veins) return back to the place from whence it issued first: and, by that time it comes thither, it is grown cool and thick, & needs a vigorous restauration of spirits

and a new rarifying, that then it may warm the flesh it passes a∣gain through; without which it would suddenly grow stone cold. As is manifest, if, by tying or cutting the arteries, you in∣tercept the blood which is to nourish any part: for then that part grows presently cold and benum'd.

But, referring the particulars of this doctrine to Dr. Har∣vey, who hath both invented and perfected it: our task in hand * 1.262 calls upon us, to declare in common the residue of motions that all Living Creatures agree in. How Generation is per∣form'd, we have determin'd in the past discourse: Our next con∣sideration then ought to be of Nutrition and Augmentation. Be∣tween which there is very little difference, in the nature of their actions: and the difference of their names is grounded, more upon the different result in the period of them, then upon the thing it self; as will by and by appear. Thus then is the pro∣gress of this matter. As soon as a living creature is formed, it endeavours straight to augment it self, and employs it self on∣ly about that; the parts of it being yet too young and tender, to perform the other functions which nature hath produced them for. That is to say, the Living Creature at its first production is in such a state and condition, that it is able to do nothing else but, by means of the great heat in it, to turn in∣to its own substance the abundance of moysture that over∣flows it.

They who are curious in this matter tell us, that the perfor∣mance of this work consists in five actions; which they call Attraction, Adhesion, Concoction, Assimulation, and Unition. The nature of Atraction we have already declared; when we ex∣plicated how the heart and the root sends juice into the other parts of the Animal or Plant: for they, abounding in them∣selves with inward heat, and besides that, much other circum∣stant heat working likewise upon them; it cannot be otherwise, but that they must needs suck and draw into them the moisture that is about them.

As for Adhesion, the nature of that is likewise explicated; when we shew'd how such parts as are moist, but especially aerial or oily ones, (such as are made by the operation of a soft and continual heat), are catching and easily stick to any

body they happen to touch: and how a little part of▪ moysture between two dry parts joyns them together. Upon which oc∣casion, it is to be noted that parts of the same kind joyn best together: and therfore the powder of glass is used to ciment broken glass withal (as we have touch'd somwhere a∣bove), and the powder of marble to ciment marble with; and so of other bodies. In like manner, Alchimists find no better expe∣dient to extract a small proportion of silver mixed with a great one of gold, then to put more silver to it: nor any more effectual way to get out the heart, or tincture, or spirits, of any thing they distil or make an extract of; then to infuse its own flegme upon it, and to water it with that. Now, whether the reason of this be, that continuity, because it is an unity, must be firmest between parts that are most conformable to one another, and consequent∣ly nearest one among themselves; or whether it be for some other hidden cause, belongs not to this place to discourse: but in fine so it is. And the adhesion is strongest of such parts as are most conformable to that which needs encrease and nou∣rishment; and that is made up by the other three actions.

Of which, Concoction is nothing else but a thickning of that juice which already sticks to any part of the Animals body, by the good digestion that heat makes in it. And Assimilation is the effect of Concoction: for, this juice being used in the same manner, as the first juice was that made the part wherto this is to be joyn'd, it cannot chuse but become like it in substance; And then, there being no other substance between, it is of it self united to it, without any further help.

Hitherto this action belongs to Nutrition. But if, on the one * 1.263 side, the heat and spirituality of the blood, and, on the other side, the due temper and disposition of the part be such, as the bloud is greedily suck'd into the part, (which therby swells to make room for it, and will not let it go away, but turns it into a like substance as it self is, and is greater in quantity, then what is consumed and decayes continually by transpiration: then this action is called likewise Augmentation. Which Galen expli∣cates, by a sport the boys of Ionia used; who were accustom'd to fill a bladder with wind, and, when they could force no more into it, they could rub the bladder; and, after rubbing of it, they

found it capable of receiving new breath; and so they would proceed on, till their bladder were as full, as by use they knew it could be made. Now (saith he) nature doth the like, by filling our flesh and other parts with bloud; that is to say, it stretches the fibers: but she hath, over and above, a power which the boys had not, namely, to make the fibers as strong after they are stre∣tched to their utmost extension, as they were before they were extended; whence it happens, that she can extend them again as well as at the first, and this without end, as far as concerns that part.

The reason wherof is, because she extends them by means of a liquor, which is of the same nature as that wherof they were made at first: and from thence it followes, that, by concoction, that liquour settles in the parts of the fibers which have most need; and so makes those parts as great in the length they are ex∣tended to, as they were in their shortness before they were drawn out. Whereby the whole part of the Animal, wherin this happens, grows greater: and, the like being done in every part, as well as in any one single one, the whole Animal becomes bigger; and is in such sort augmented.

Out of all which discourse, we may collect that, in the essen∣tial * 1.264 composition of Living Creatures, there may peradventure be a phisical possibility for them to continue always without decay; and so become immortals even in their bodies, if all hurtful accidents coming from without might be prevented. For, see∣ing that a man, besides the encrease which he makes of himself, can also impart to his children a vertue, by which they are able to do the like; and to give again to theirs, as much as they receiv'd from their Fathers: 'tis clear, that what makes him die is no more the want of any radical power in him, to en∣crease or nourish himself; then, in fire, it is the want of power to burn, which makes it go out. But, it must be some acciden∣tal want; which Gallen attributes chiefly to the driness of our bones, and sinews, &c. as you may in him see more at large. For, driness with density alows not easie admittance to moy∣sture, and therfore it causes the heat, which is in the dry body, either to evaporate, or to be extinguish'd: and want of heat is that from whence the failing of life proceeds

which he thinks cannot be prevented by any art or indu∣stry.

And herein God hath express'd his great mercy and goodness towards us. For, seeing that, by the corruption of our own nature, we are so immers'd in flesh and blood, as we should for ever de∣light to wallow in their mire; without raising our thoughts at any time above that low and brutal condition: he hath engaged us, by a happy necessity, to think of and provide for a nobler and far more excellent state of living, that will never change or end.

In pursuance of which inevitable ordinance, Man (as if he were grown weary and out of love with this life; and scorn'd any Term in his farm here, since he cannot purchase the Fee-simple of it) hastens on his death by his unwary and rash use of meats, which poyson his blood: and then his infected blood, passing through his whole body, must needs in like manner taint it all at once. For the redress of which mischief, the assistance of physick is made use of: and that, passing likewise the same way, purifies the blood, and recovers the corruption occasion'd by the peccant humour; or other whiles, gathering it together, it thrusts and carries out that evil guest, by the passages contriv'd by nature to disburden the body of unprofitable or hurtful su∣persluites.

CHAP. XXVII. Of the motions of Sence; and of the Sensible Qualities in general: and, in particular, of those which belong to Touch, Tast, and Smelling.

HAving thus brought on the course of Nature as high as Li∣ving Creatures, whose chief species or division is those that * 1.265 have sense; and having declared the operations which are common to the whole tribe of them, which includes both Plants and Animals: 'tis now time we take a particular view of those, whose action and passion is the reason why that chief portion of life is termed sensitive; I mean the Senses, and the qualities by which the outward world comes into the living creature through his senses. Which when we shall have gone through,

we shall scarcely have left any qualities among bodies, to plead for a spiritual manner of being or working, that is, for a self∣entity an instantaneous operation; which kind of things and properties vulgar Philosophy is very earnest to attribute to our senses: with what reason, and upon what ground, let us now consider.

These qualities are reduced to five several heads; answerable to so many different wayes, wherby we receive notice of the bo∣dies * 1.266 that are without us And accordingly, they constitute a like number of different Senses: of every one of which we will discourse particularly, when we have examined the natures of the qualities that affect them. But now, all the consideration we shall need to have of them is only this; That it is manifest, the organs in us, by which sensible qualites work upon us, are cor∣poreal, and made of the like ingredients as the rest of our body is: and therfore must of necessity be liable to suffer evil, and re∣ceive good (as all other bodies do) from those active qualities which make and mar all things within the limits of Nature. By which terms of Evil and Good, I mean those effects that are averse or conformable to the particular nature of any thing; and therby tend to the preservation or destruction of that indivi∣dual.

Now we, receiving from our senses the knowledge we have of things without us, give names to them, according to the passions and affections which those things cause in our senses: which being the same in all mankind (as long as they are consi∣der'd in common, and their effects are look'd upon in gross), all the world agrees in one Notion and Name of the same thing; for every man living is affected by it just as his neigh∣bour is, and as all men else in the world are. As for exam∣ple; Heat or Cold works the same feeling in every man com∣posed of flesh and bloud: and therfore whoever should be ask'd of them would return the same answer, that they cause such and such affects in his sense; pleasing or displeasing to him, ac∣cording to their degrees, and as they tend to the good or evil of his whole body.

But, if we descend to particulars, we shall find that several men of differin•• constitutions frame different notions of the

same things; according as they are conformable or disagreeing to their natures: and accordingly, they give them different names. As when the same liquor is sweet to some mens tast, which to anothers appears bitter: one man takes that for a perfume, which to another is an offensive smel. In the Turkish Baths, (where there are many degrees of heat in divers rooms, through all which the same person uses to pass, and to stay a while in every one of them, both at his entrance and going out; to season his body by degrees for the contrary excess he is going to) that seems chilly-cold at his first return, which appear'd melting hot at his going to it: as I my self have often made experience in those Countreys. Beauty and loveliness will shine to one man in the same face, that will give aversion to another. All which proclaims, that the Sensible Qualities of Bodies are not any positive real thing, consisting in an indivisible and distinct from the body it self; but are meerly the very body, as it affects our senses: to discover how they do, which must be our labour here.

Let us therfore begin with considering the difference be∣tween sensible and insensible creatures. These later lie exposed to the mercy of all outward agents, that from time to time (by the continual motion which all things are in) come within di∣stance of working upon them: and they have no power to re∣move themselvs from what is averse to their nature; nor to ap∣proach nearer what comforts it. But the others, having with∣in themselvs a principle of motion, (as we have already de∣clared), are able, whenever such effects are wrought on them, as on the others, upon their own account and by their own action, to remove themselvs from what begins to annoy them, and to come nearer to what they find a beginning of good by.

These impressions are made on those parts of us, which we call the Organs of our Senses: and by them give us seasonable ad∣vertisements and knowledges, wherby we may govern and or∣der, to the best advantage, our little charge of a body; according to the tune or warnings of change in the great circumstant body of the world, as far as it may concern ours. Which how it is done, and by what steps it proceeds, shall be in the following discourse laid open.

Of this great machine that environs us, we, who are but a small parcel, are not immediately concern'd in every part. It imports not us, for the conservation of our body, to have knowledge of other parts then such are within the distance of working upon us: those only, within whose sphere of activity we are planted, can offend or advantage us; and of them some are near us, others further from us. Those that are next us we dis∣cern (according as they are qualified), either by our Touch, or our Tast, or our Smelling: which three Senses manifestly appear to consist in a meer gradation of more or less gross; and their operations are level'd to the three Elements that press upon us, Earth, Water, and Air. By our other two Senses (our Hearing and our Seeing) we have notice of things further off; and the agents which work on them are of a more refined nature.

But we must treat of them all in particular: and that which we will begin with shall be the Touch; as being the grossest of * 1.267 them, and that which converses with none but the most material and massie objects. We see, it deals with heavy consistent bodies; and judges of them by conjunction to them, and by immediate reception of something from them. And, according to the divers impressions they make in it, it distinguishes them by divers names; which (as we said of the qualities of mixed bodies) are generally reduced to certain pairs: as, hot and cold, wet and dry, soft and hard, smooth and rough, thick and thin, and some others of the like nature; which were needless to enumerate, since we pretend not to deliver the science of them, but only to shew that they and their actions are all corporeal.

And, this is sufficiently evident, by meer repenting but their very names: for 'tis plain by what we have already said, that there are nothing else but certain effections of quantity, ari∣sing out of different degrees of rarity and density compounded together. And 'tis manifest, by experience, that our sense receivs the very same impressions from them which another body doth. For, our body or our sense will be heated by fire; burn∣ed by it too, if the heat be too great, as well as wood: it will be constipated by cold water, moistened by humide things, and dryed by dry bodies; in the same manner as any other body

whatever, Likewise, it may, in such sort as they, be wounded and have its continuity broken by hard things, be pleas'd and polish'd by soft and smooth, be press'd by thick and heavy, and rub'd by those that are rugged, &c.

So that those Masters, who will teach us that the impressions upon sense are made by spiritual or spirit-like things or quali∣ties, (which they call intentional specieses), must labour at two works: the one, to make it appear that there are in nature such things as they would perswade us; the other, to prove that these material actions we speak of are not able to perform those eff••cts, for which the senses are given to living creatures. And, till they have done that, I conceive, we should be much too blame to ad∣mit such things, as we neither have ground for in reason, nor can understand what they are. And therfore, we must resolve to rest in this belief, which experience breeds in us, that these bodies work on our senses, no other ways then by a corporeal operati∣on; and that such a one is sufficient for all the effects we see pro∣ceed from them: as, in the process of this discourse, we shall more amply declare.

The Element immediately next to Earth in grosness is Wa∣ter. And in it is the exercise of our tast; or Mouth being per∣petually * 1.268 wet within; by means of which moysture, our Tongue receives into it some little parts of the substance which we chew in our Teeth, and which passes over it. You may ob∣serve how, if we take any herb or fruit, and, having chop'd or beaten it small, put it into a wooden dish of water and squeeze it a little; the juice, communicating and mingling it self with the water, infects it with the tast of it self, and, remaining a while in the bowl, sinks by little and little into the very pores of the wood: as is manifest, by its retaining a long time after the tast and smell of that herb. In like manner, nature hath taught us, by chewing our meat, and by turning it in our mouths and pressing it a little (that we may the more easily swallow it), to imbue our Spittle with such little parts as easily diffuse themselvs in water. And then, our Spittle being conti∣nuate to the moysture within our tongue, (in such sort as we declared of the moisture of the earth, that soaks into the

root of a plant), and particularly in the sinews of it, must of ne∣cessity affect those little sensible strings with the qualities which these petty bodies, mixed every where with the moisture, are themselves imbued withal.

And if thou ask, what motions or qualities these be? Physiti∣ans (to whom it belongs most particularly to look into them) will tell you, that some dilate the tongue more, and some less; as if some of these little bodies had an aereal, and others a wa∣try disposition: and these two they express by the names of sweet and fatty. That some contract and draw the tongue to∣gether; as choaky and rough things do most, and, next to them, crabby and immature sharpness. That some corrode and pierce the Tongue; as Salt and sowre things. That bitter things search the outside of it, as if they swept it: and that other things as it were prick it; as spices and hot drinks. Now all these are sensible material things; which admit to be explicated clearly, by the varieties of rarity and density concurring to their compositions; and are so proportionable to such material instruments, as we cannot doubt but they may be throughly declared by our for∣mer principles.

The next Element above Water is Air; which our Nostrils being our Instrument to suck in, we cannot doubt but what af∣fects * 1.269 a man by his Nose must come to him in Breath or Air. And, as humidity receives grosser and weightier parts, so those which are more subtile and light rise up into the Air: and these we know attain to this lightness by the commixtion of fire, which is hot and dry. And therfore we cannot doubt, but that the nature of Smells is more or less tending to heat and drought: which is the cause that their commixtion with the brain proves comfortable to it; because, of its own disposition, it is usually subject to be too moist and too cold.

Whether there be any immediate instrument of this sense to receive the passion or effect, which by it other bodies make up∣on us, or whether the sense it self be nothing but a passage of these exhalations and little bodies to the brain, fitly accom∣modated to discern what is good or hurtful for it, and accord∣ingly to move the body to admit or reject them; it imports

not us at present to determine: let Physicians and Anatomists resolve that question, Whiles it suffices us to understand, that the operations of bodies by Odours upon our sense, are per∣form'd by real and solid parts of the whole substance; which are truly material, though very little bodies; and not by imaginary qualities.

And those bodies, when they proceed out of the same things * 1.270 that yield also tastive particles, (although without such materi∣al violence, and in a more subtile manner), must of necessity have in them the same nature, which those have that affect the tast; and they must both of them affect a man much alike, by his tast by his smell: and so are very proportionate to one another; ex∣cepting in those properties which require more cold or liqui∣dity then can well stand with the nature of a smell. And ac∣cordingly, the very names, which men have imposed to ex∣press the affections of both, many times agree; as savour and sweet which are common both to the smell and tast; the strong∣est of which we see oftentimes make themselves known, as well by the one as by the other sense; and either of them in excess will turn a mans stomack. And, the Physicians that write of these senses find them very conformable: whence it happens that the losing of one of them is the losse also of the other.

And, experience teaches us in all Beasts, that the Smell is gi∣ven to living creatures, to know what meats are good for them, and what are not. And accordingly, we see them still smell for the most part at any unknown meat, before they touch it; which seldom fails of informing them rightly: nature ha∣ving provided this remedy against the gluttony, which could not choose but follow the convenient disposition and temper of their parts and humours; through which they often swallow their meat greedily and suddenly, without expecting to try it first by their tast: Besides that, many meats are so strong, that their very tasting them after their usual manner would poison, or at least greatly annoy them: and therfore nature hath pro∣vided this sense, to prevent their tast; which being far more subtile then their tast, the final atoms by which it is perform'd are not so very noxious to the health of the Animal, as the other grosser atoms are.

And doubtlesly, the like use men would make of this sense; had they not, on the one side, better means then it to know the * 1.271 qualities of meats, and therfore, this is not much reflected on: And, on the other side, were they not continually stuff'd and clogg'd with gross vapours of streamy meats, which are daily reeking from the Table and their stomacks; and permit not pu∣rer Atomes of bodies to be discerned, which require clear and uninfected organs to take notice of them. As we see it fare with doggs: who have not so true and sensible noses, when they are high fed, and lie in the kitchin amidst the steams of meat; as when they are kept in their kennel, with a more spare diet, fit for hunting.

One full example this age affords us in this kind; of a man, whose extremity of fear wrought upon him to give us this ex∣periment. He was born in some Village of the Countrey of Liege: and therfore, among strangers, he is known by the name of John of Liege. I have been informed of this story by seve∣ral, (whom I dare confidently believe) that have had it from his own mouth; and have question'd him, with great curiosity, particularly about it.

When he was a little boy, there being wars in the Countrey, (as that State is seldom without molestations from abroad, when they have no distempers at home, which is an inseparable effect of a Countries situation upon the Frontiers of powerful neighbouring Princes that are at variance), the village of whence he was had notice of some unruly scatter'd Troups that were coming to pillage them: which made all the people of the vil∣lage flie hastily with what they could carry with them, to hide themselves in the woods; which were spacious enough to afford them shelter, for they joyn'd upon the Forrest of Ardenne. There they lay, till some of their Scouts brought them word, that the Souldiers, of whom they were in such apprehension, had fired their Town and quitted it. Then all of them return'd home, ex∣cepting this boy: who, it seems, being of a very timorous na∣ture, had images of fear so stròg in his phantasie, that first he ran further into the wood then any of the rest, and afterwards ap∣prehended that every body he saw through the thickets, and every voice he heard, was the Souldiers; and so hid himself from

his parents, that were in much distress seeing him all about, and calling his name as loud as they could. When they had spent a day or two in vain, they return'd home without him; and he li∣ved many years in the woods, feeding upon roots and wild fruits, and maste.

He said that, after he had been some time in this wilde habi∣tation, he could by the smel judge of the tast of any thing that was to be eaten: and that he could, at a great distance, wind by his nose, where wholsom fruits or roots grew. In this state he continu'd (still shunning men with as great fear as when he first ran away; so strong the impression was, and so little could his little reason master it): till, in a very sharp win∣ter, when many beasts of the forrest perish'd for want of food, necessity brought him to so much confidence, that, leaving the wild places of the forrest, remote from all peoples dwellings, he would, in the evenings, steal among cattel that were fothered; especially the Swine, and, among them, glean that which serv'd to sustain wretchedly his miserable life. He could not do this so cunningly, but that, returning often to it, he was on a time e∣spied: and they who saw a beast of so strange a shape (for such they took him to be, he being naked and all overgrown with hair), believing him to be a Satyre or some such prodigious crea∣ture as the recounters of rare accidents tells of, laid wait to ap∣prehend him. But he, that winded them as far off as any beast could do, still avoided them; till at length, they laid snares for him, and took the wind so advantagiously of him, that they caught him: and then soon perceiv'd he was a man, though he had quite forgotten the use of all language; but by his gestures and cries he express'd the streatest affrightedness that might be. Which afterwards he said (when he had learn'd a new to speak) was because he thought those were the souldiers he had hidden himself to avoid, when he first betook himself to the Wood; and were alwayes lively in his phantasie, through his fears continu∣ally reducing them thither.

This man, within a little while after he came to good keep∣ing and full feeding, quite lost that accuteness of smelling, which formerly govern'd him in his taste; and grew to be in that par∣ticular as other ordinary men were. But, at his first living with

other people, a woman (that had compassion of him, to see a man so near like a beast, and that had no language to call for what he wish'd or needed to have) took particular care of him; and was alwayes very sollicitous to see him furnish'd with what he wan∣ted: which made him so apply himself unto her in all his occur∣rents, that, whenever he stood in need of ought, if shee were out of the way, and were gone abroad in the fields, or to any other village near by, he would senther out presently by his scent; in such sort as with us those dogs use to do which are taught to draw dry foot. I imagine he is yet alive, to tell a better story of himself then I have done; and to confirm what I have here said of him: for, I have from them who saw him but few years agone, that he was an able strong man, and likely to last yet a good while longer.

And of another man I can speak assuredly my self; who, be∣ing a very temperate or rather spare diet, could likewise per∣fectly discern by his smel the qualities of whatever was after∣wards to pass the examination of his taste, even to his bread and bear. Wherfore to conclude, 'tis evident both by reason and ex∣perience, that the objects of our Touch, our Taste, and our Smel, are material and corporeal things, derived from the division of quantity into more rare and more dense parts; and may with ease be resolved into their heads and springs, sufficiently to content any judicious and rational man. Who, if he be curious to have further satisfaction in this particular (as far as concerns odours and savours), may look over what Johannes Bravus (that judici∣ous, though unpolish'd, Physitian of Salamanca) hath written thereof.

CHAP. XXVIII. Of the sense of Hearing, and of the sensible quality, Sound.

BUt, to proceed with the rest of the Senses. Because nature * 1.272 saw, that some things came suddenly upon a living creature, which might do it hurt, if they were not perceiv'd afar off; and that other things were placed at distance from it, which would greatly help it, if it could come near to them: she found a means to give us two Senses more, for the discovery of remote things. The one, principally and particularly, to descry their motion. The other, to mark their bulk and situation.

And so, to begin with the former of these; we must needs ac∣knowledge (after due examination of the matter) that the thing which we call sound is purely motion. And if it be objected, that many motions are made without any discernable Sound; We shall not make difficulty to grant it; considering that many mo∣tions dye before they come to touch the ear; or else are so weak, that they are drown'd by other stronger motions; which round about besiege our ears in such manner, that notice is not taken of these. For, so it fares in what depends meerly of quantity, especially concerning our senses; that not every thing of the kind, but a determinate quantity or multitude of parts of it, makes an object sensible.

But, to come close to the point: We see that Sound, for the most part, is made in the air; and that, to produce it, there is re∣quired a quick and smart motion of that Element, which, of all the the rest, is the most moveable. And, in motion, velocity or quickness is proportionate to density in magnitude (as we have at large declared): Which makes quantity become perceptible in bulk, as this doth in motion. And, as the one consists in a greater proportion of substance to the same quantity; so the other doth, in the passage of more parts of the medium in the same time.

And, in the moderating of this, such of the Liberal Arts are employ'd, as belong to the cultivating mans voice: as Rhe∣torick, Meetering, and Singing. 'Tis admirable how finely Ga∣lileo

hath deliver'd us the consonances of Musick (towards the end of his First Dialogue, of Motion; from the 95 page, forward * 1.273 on), and now he hath shew'd that matter clearly to the sight (so making the eye as well as the ear Judge of it), in motions of the water, in Pendants hanging loose in the air, and in per∣manent notes or traces made upon letton. To the moderation of the same, many other mechanical arts are imply'd; as the Trade of Belfounders, and of all Makers of musical instruments by wind, or by water, or by strings.

Neither can I slip over without mention the two curious Arts of Echoing and Whispering. The first of which teaches to iterate voices several times; and is frequently put in practice by those, that are delighted with rarities in their gardens: And the other shews how to gather into a narrow room the moti∣ons of the air, that are diffused in a great extent; wherby one that shall put his ear, to that place where all the several moti∣ons meet, shall hear what is spoken so low, as no body between him and the speaker can discern any sound at all. Of which kind there are very fine curiosities in some Churches of England: and my self have seen, in an upper room of a capacious round Tower vaulted overhead, the walls so contrived (by chance I believe); that two men, standing at the utmost opposite points of the Diameter of it, could talk very currently and clearly with one another, and yet none that stood in the middle could hear a sillable. And, if one turn'd his face to the wall and spoke against that (though never so softly); the others ear, at the opposite point, would discern every word. Which puts me in mind of a note made by one that was no friend to Au∣ricular Confession, (upon occasion of his being with me in a Church that had been of a Monastery); where, in one corner of it, one might sit and hear almost all that was whisper'd through the whole extent of the Church: who would not be perswaded but that it was on purpose contrived so by the subtilty of the Friars; to the end that the Prior, or some of them, might sit there and hear whatever the several Penitents accused them∣selvs of to their Ghostly Fathers, so to make advantage by this artifice, of what the Confessors durst not of themselvs immedi∣ately reveal.

He allow'd better of the use in Rome, of making voyces re∣bound,

from the top of the Cupula of St. Peters in the Vatican, down to the floor of the Church; when, on great days, they make a Quire of Musick go up to the very highest part of the arch, which is, into the Lanthorn: from whence while they sing, the people below just under it are surprised with the smart sound of their voices, as though they stood close by them, and yet can see no body from whom these notes should proceed. And in the the same Cupula, if two men stand upon the large cornish or border, which circles the bottom of it; they may observe the like effect as that I spoke of above in the round Tower.

In like manner, they that are called Ventriloqui, perswade igno∣rant people, that the Devil speaks from within them (deep in their belly); by their sucking their breath inwards, in a certain manner, whiles they speak: whence it follows, that their voice seems to come not from them, but from somwhat else hidden within them; if at least you perceive it comes out of them; but, if you do not, then it seems to come from a good way off.

To this art belongs the making of Sarabatanes or Trunks, to help the hearing; and of Echo-glasses, that multiply sounds, as Burning-glasses do light. All which arts, and the rules of them, follow the laws of motion; and every effect of them is to be demonstrated by the principles and proportions of motion: therfore, we cannot with reason imagine them to be any thing else.

We see likewise, that great noises, not only offend the hearing, but even shake houses and Towers. I have been told by inhabi∣tants * 1.274 of Dover, that, when the Arch-Duke Albertus made his great battery aganst Calais (which for the time was a very furi∣ous one; for he endeavor'd all he could to take the Town before it could be reliev'd): the very houses were shaken, and the glass∣windows shiver'd, with the report of his Artillery. And I have been told by one that in Sevil, when the gunpowder-house of that Town (which was some two miles distant from that place where he lived) was blown up; that it made the wooden shutters of the windows in his house beat and clap against the walls with great violence: and split the very walls of a fair Church, that, standing next it (though at a good di∣stance), hand no other building between to shelter it from the

impetuosity of the airs sudden violent motion.

And, after a fight I once had with some Galleasses and Galli∣ones in the rode of Scanderone (which was a very hot one for the time, and a scarce credible number of pieces of Ordnance were shot from my Fleet); the English Consul of that place coming afterwards aboard my ship told me, that the report of our guns had, during all the time of the fight, shaken the drin∣king-glasses that stood upon shelvs in his house, and split the pa∣per-windows all about, and spoil'd and crack'd all the eggs that his Pigeons were then sitting uppon: which loss he lament∣ed exceedingly; for they were of that kind which commonly it called Carriers, and serve them daily in their commerce be∣tween that place and Aleppo.

And, I have often observed at Sea, in smooth water, that the Ordnance shot off, in a ship some miles distant, would violently shake the glass-windows in another: And I have perceiv'd this effect in my own, more then once; at the report of a single gun from a ship, so far off, that we could not descry her. I remem∣ber how, one time upon such an occasion, we alter'd our course and steer'd with the sound, or rather with the motion at first; observing upon which point of the Compass the shaking ap∣pear'd (for we heard nothing, though soon after, with much at∣tention and silence, we could discerna dul clumsie noise). And such a motion grows at the end of it so faint, that, if any strong resisting body check it in its course, 'tis presently deaded and will afterwards shake nothing beyond that body: and therfore 'tis perceptible onely at the outside of the ship, if some light and very moveable body hang loosly on that side it comes, to receive the impression of it; as this sound at the gallery windows of my Cabin upon the poop, which were of light Moscovia glass. And by then we had run somwhat more then a watch, with all the sails abroad we could make, and in a fair loom gale; we found our selvs near enough to part the fray of two ships, that, in a little while longer fighting would have sunk one another. * 1.275

But, besides the motions in the air (which receiv'd them easi∣ly, by reason of the fluidity of it); we see that even solid bodies participate of it. As, if you knock never so lightly at one end of the longest beam you can find; it will be distinctly heard at the other end. The trampling of men and horses, in a quiet night, wil

be heard some miles off, if one lay their ear to the ground; and more sensibly, if one make a little hole in the earth, and put ones ear into the mouth of it: but most of all, if one set a Drum smooth upon the ground, and lay ones ear to the upper edge of it; for, the lower membrane of the Drum is shaked by the mo∣tion of the earth, and then multiplies that sound by the hol∣low figure of the Drum, in the conveying it to the upper mem∣brane upon which your ear leans. Not much unlike the Tym∣pane or Drum of the ear; which, being shaked by outward motion, causes a second motion on the inside of it correspon∣dent to this first; and this, having a free passage to the brain, strikes it immediately, and so informes it how things move without; which is all the mystery of hearing.

If any thing break or stop this motion, before it shake our * 1.276 ear, it is not heard. And accordingly, we see that the sound of Bells or Artillery is heard much further, if it have the conduct of waters, then through the pure air: because in such bodies, the great continuity of them makes that one part cannot shake alone, and upon their superficies there is no notable unevenness, nor any dense thing in the way to check the motion (as in the air, hills, buildings, trees, and such like;) so that the same shaking goes a great way. And, to confirm that this is the true reason, I have several times observ'd that, standing by a river side, I heard the sound of a ring of Bells much more distinctly and loud, then if I went some distance from the water, though nearer to the steeple from whence the sound came.

And it is not only the motion of the air, that makes sound * 1.277 in our ears: but any motion that hath access to them, in such a manner as to shake the quivering membranous Tympane within them, will represent to us those motions which are without, and so make such a sound there as if it were convey'd onely by the air. Which is plainly seen, when a man, lying a good way under water, shall there hear the same sounds, as are made above in the air; but in a more clumsie manner; accord∣ing as the water, by being thicker and more corpulent, is more unwieldy in its motions. And this I have tryed often; staying under water as long as the necessity of breathing would permit me. Which shews that the air, being smartly moved, moves the water also, by means of its continuity with it; and that li∣quid

element, being fluide and getting into the ear, makes vi∣brations upon the drum of it like to those of air.

But all this is nothing, in respect of what I might in some sort say, and yet speak truth. Which is, that I have seen one, who * 1.278 could discern sounds with his eyes. 'Tis admirable, how one sense will oftentimes supply the want of another: whereof I have seen an other strange example, in a different strain from this; of a man that, by his grosser senses, had his want of sight wonderfully made up. He was so throughly blind, that his eyes could not inform him when the Sun shined; for all the cry: stalline humour was out in both his eyes: yet his other senses instructed him so efficaciously, in what was their office to have done, as what he wanted in them seem'd to be overpay'd in other abilities. To say that he would play at Cards and Tables, as well as most men, is rather a commendation of his memory & phanta∣sie, then of any of his outward senses: But, that he should play wel at Bowles and Shovelbord and other games of aim, which in other men require clear sight and an exact level of the hand, according to the qualities of the earth or table, and to the situ∣ation and distance of the place he was to throw at; seems to ex∣ceed possibility. And yet he did all this.

He would walk in a chamber, or long alley in a garden (after he had been a while used to them) as straight, and turn as just at the ends, as any seeing man could do. He would go up and down every where so confidently, and demean himself at ta∣ble so regularly; as strangers have sitten by him several meals, and seen him walk about the house, without ever observing any want of seeing in him: which he endeavour'd what he could to hide; by wearing his hat low upon his brows. He would, at the first abord of a stranger, as soon as he spoke to him, frame a right apprehension of his stature, bulk and manner of making. And, which is more, when he taught his Schollers to declame (for he was School-master to my sons, and lived in my house) or to represent some of Seneca's Tragedies, or the like; he would by their voice know their gesture, and the situation they put their bodies in: so that he would be able, as soon as they spoke, to judge whether they stood or sate, or in what posture they were; which made them demean themselvs as decently before him whiles they spoke, as if he had seen them perfectly.

Though all this be very stange, yet me thinks his discerning of lights is beyond it all. He would feel in his body, and chiefly in his brain (as he hath often told me) a certain effect, by which he knew when the Sun was up; and would discern exactly a clear from a cloudy day. This I have known him frequently do without missing, when, for trial sake, he has been lodged in a close chamber, whereto the clear light or Sun could not arrive, to give him any notice by its actual warmth: nor any body could come to him, to give him private warnings of the Chan∣ges of the weather,

But this is not the relation I intended, when I mention'd one that could hear by his eyes; (if that expression may be permit∣ed * 1.279 me). I then reflected upon a Noble man of great quality that I knew in Spain; the younger brother of the Constable of Castile. But, the reflection of his seeing of words, call'd into my remembrance the other that felt light: in whom I have often re∣mark'd so many strange passages, with amazement and delight; that I have adventured upon the Readers patience to record some of them, conceiving they may be of some use in our course of doctrine. But, the Spanish Lord was born deaf; so deaf, that, if a Gun were shot off close by his ear, he could not hear it: and consequently, he was dumb; for not being able to hear the sound of words, he could never imitate nor under∣stand them, The loveliness of his face, and especially the excee∣ding life and spiritfulness of his eyes, and the comliness of his person & whole composure of his body throughout, were preg∣nant signs of a well temper'd mind within: and therfore all that knew him lamented much the want of means to cultivate it, and to imbue it with the motions which it seem'd capable of, in regard of its self; had it not been so cross'd by this un∣happy accident. Which to remedy, Physitians and Chyrurgi∣ans had long imploy'd their skil; but all in vain: at last, there was a Priest who undertook the teaching him to understand others when they spoke, and to speak himself that others might understand him. What at the first he was laught at for, made him, after some yeers, be looked on as if he had wrought a miracle. In a word, after strange patience, constancy and pains, be brought the young Lord to speak as distinctly as any man whoever; and to understand so perfectly what

others said, that he would not lose a word in a whole days con∣versation.

They who have a curiosity, to see by what steps the Master proceeded in teaching him, may satisfie it by a Book which he himself hath written in Spanish upon that subject, to instruct others how to teach deaf and dumb persons to speak. Which when one shall have looked heedfully over, and consider'd what a great distance there is between the simplicity and nakedness of his first principles, and the strange readiness and vast extent of speech resulting in process of time out of them: we will for∣bear pronouncing an impossibility in their pedegree, whiles he wonders at the numerous effects resulting in bodies out of rarity and density, ingeniously mingled together by an all∣knowing Architect, for the production of various qualities among mixts, of strange motions in particular bodies, and of admirable operations of life and sense among vegetables and animals. All which are so many several words of the mystical language; in which the Great Master hath taught his otherwise∣dumb schollars (the Creatures), to proclaim his infinite art, wisdome, perfections, and excellency.

The Priest who, by his book and art, occasion'd this discourse, I am told is still alive, and in the service of the Prince of Ca∣rignan; where he continues (with some that have need of his pains) the same imployment he had with the Constables brother: with whom I have often discoursed, whiles I waited on the Prince of Wales (now our gracious Soveraign) in Spain. And I doubt not but His Majesty remembers all I have said of him, and much more: for, His Majesty was very curious to observe and enquire into the utmost of it. It is true, one great misbecomingness he was apt to fall into, whiles he spoke; which was, an uncertainty in the tone of his voyce: for, not hearing the sound he made when he spoke, he could not steadily govern the pitch of his voyce; but it would be somtimes higher, sometimes lower; though, for the most part, what he deliverd together he ended, in the same key as he begun it. But, when he had once suffered the passages of his voyce to close; at the opening them again, chance, or the measure of his earnestness to speak or re∣ply, gave him his tone: which he was not capable of modera∣ting by such an artifice, as 'tis recorded Caijus Grachus used,

when passion, in his Orations to the people, drove out his voyce with too great a vehemence or shrilness.

He could discern in another, whether he spoke shril or low: and he would repeat after any body any hard word whatever. Which the Prince tryed often; not only in English, but by ma∣king some Welchmen that served his Highness speak words of their language: Which he so perfectly ecchoed, that I con∣fess I wonder'd more at that, then at all the rest. And his Master himself would acknowledg, that the rules of his art reach'd not to produce that effect with any certainty: and therefore con∣cluded, this in him must spring from other rules he had framed to himself, out of his own attentive observation; which, the ad∣vantage that nature had justly given him in the sharpness of his other senses, to supply the want of this, endow'd him with an ability and sagacity to do, beyond any other man that had his hearing. He express'd it (surely) in a high measure, by his so exact imitation of the Welch pronunciation: for, that tongue (like the Hebrew) employs much the guttural Letters; and the motions of that part which frames them cannot be∣seen or judg'd by the eye, otherwise then by the effect they may happily make by consent in the other parts of the mouth, exposed to view. For, the knowledg he had of what they said sprung, from his observing the motions they made: so that he could converse currently in the light, though they he talked with whisper'd never so softly: and I have seen him, at the distance of a large chambers breadth, say words after one, that I, stand∣ing close by the speaker could not hear a syllable of. But, if he were in the dark, or if one turned his face out of his sight, he was capable of nothing one said.

But, 'tis time we return to our theam; from whence my blind * 1.280 Schoolmaster, and this deaf Prince (whose defects were over∣pai'd an other way) have carried us with so long a digression: which let yet will not be altogether useless (no more then the former, of the wild man of Liege); if we make due reflecti∣ons on them. For, when we shall consider, that Odors may be tasted, that the relish of meats may be smelled, that magnitude and figure may be heard, that light may be felt, and that sounds may be seen; (all which is true in some sense): we may by this changing the offices of the senses, and by looking

into the causes therof, come to discern, that these effects are not wrought by the intervention of aiery qualities; but by real and material applications of bodies, to bodies, which, in different manners, make the same results within us.

But when I suffer'd my pen to be steer'd by my phantasie, that pleas'd it self and rioted in the remembrance of these two no∣table persons: I was speaking, how the stong continuity of the parts of a thing that is moved draws on the motion, and conse∣quently the sound, much further than wherethat which is moved suffers breaches, or the rarity of it occasions that one part may be moved without another; for, to the proportion of the shaking, the noise continues. As we see in trembling Bells, that hum a great while longer then others, after the Clapper has strucken them: and the very sound seems to quiver and shake io our ears, proportionable to the shaking of the Bell. And in a Lute, as long as a string that hath been strucken shakes sensibly to our eye; so long, and to the same measure, the sound shakes in our ear. Which is nothing else but an undu∣lation of the Air, caused by the smart and thick vibrations of the cord, and multiply••d in the belly of the instrument (which is the reason that the concave figure is affected in most): and so, when it breaks out of the instrument, in greater quantity then the string immediately did shake; it causes the same undulati∣ons in the whole body of Air round about. And that, strik∣ing the Drum of the ear, gives notice therin what tenour the string moves; whose vibrations if one stop, by laying his finger upon it, the sound is instantly at an end: for then there is no cause on foot that continues the motion of the Air; which, without a continuation of the impulse, returns speedily to quiet; through the resistance made to it by other parts of it that are further off.

Out of all which 'tis plain, that motion alone is able to ef∣fect, and give account of all things whatever that are attri∣buted to Sound: and that Sound and motion go hand in hand together; so that whatever is said of the one is likewise true of the other. Wherfore, it cannot be deny'd but that hearing is nothing else, but the due perception of motion: and that motion and sound are in themselvs one and the same thing, though express••d by different names, and comprised in our un∣derstanding

under different notions. Which proposition seems to be yet further convinced, by the ordinary experience of perceiving musick by mediation of a stick: for, how should a deaf man be capable of musick by holding a stick in his Teeth, whose other end lies upon the Vial or Virginals; were it not that the proportional shaking of the stick (working a like dancing in the mans head) make a like motion in his brain, with∣out passing through his ear; and consequently, without being otherwise sound, then as bear motion is sound.

Or, if any man will still persist in having sound be some other thing then as we say; and that it effects the sense otherwise then purely by motion: he must nevertheless acknowledge that, whatever it be, it hath neither cause nor effect, nor breeding, nor dying, that we either know or can imagine. And then, if he will let reason sway, he will conclude it unreasonable to say or suspect so ill grounded a surmise, against so clear and solid proofs: which our ears themselvs not a little confirm, their whole figure and nature tending to the perfect receiving, con∣serving, and multiplying the motions of air which happen with∣out a man; as, who is curious may plainly see, in the Anatomists books and discourses.

CHAP. XXIX. Of Sight, and Colours.

THere is yet left the object of our Sight, which we call Co∣lours, * 1.281 to take a survey of; for, as for light, we have at large display'd the nature and properties of it; from which whether colour be different or no, will be the question we shall next discuss. For, those who are cunning in Opticks will, by refractions and reflexions, make all sorts of colours out of pure light: as we see in Rainbows, in those Triangular Glasses or Prisms (which some call Fools Paradises), and in other in∣ventions for this purpose. Wherfore in brief, to shew what colour is, let us lay for a ground, that Light is, of all other things in the world, the greatest and the most powerful agent upon our eye; either by it self, or by what comes in with it: and

that, where light is not, darkness is. Then consider, that light may be diversly cast; especially through or from a transparent body, into which it sinks in part, and in part it doth not: and you will conclude, that it cannot choose but come out from such a body, in divers sorts mingled with darkness. Which, if it be in a sensible quantity, accordingly makes divers appear∣ances; and those appearances must of necessity have divers hues, representing the colours which are middle colours be∣tween white and black: since white is the colour of light, and darkness seems black. Thus those colours are ingendred, which are call'd apparent ones. And they appear somtimes but in some one position; as in the Rainbow, which changes place as the looker on doth: but, at other times, they may be seen from any part; as those which light makes by a double re∣fraction through a Triangular Glass.

And that this is rightly deliver'd may be gather'd, out of the conditions requisite to their production. For that Chrystal, or water, or any refracting body doth not admit light in all its parts, is evident by reason of the reflection it makes, which is exceeding great; and, not only from the superficies, but even from the middle of the body within: as you may see plainly, if you put it in a dark place and enlighten but one part of it, for then you may perceive, as it were, a current of light pass quite through the body, although your eye be not opposite to the passage; so that manifestly, it reflects to your eye from all the inward parts which it lights upon.

Now, a more oblique reflection or refractiom more disper∣ses the light, and admits more privations of light in its parts, then a less oblique one: as Galileo hath demonstrated, in the First Dialogue of his Systeme. Wherefore a less oblique reflection or refraction may receive that in quality of light, which a more oblique one makes appear mingled with darkness; and conse∣quently, the same thing will appear colour in one, which shews it self plain light in another; for, the greater the in∣clination of an angle is, the greater also is the dispersion of the light.

And, as colours are made in this sort, by the medium through which light passes; so, if we conceive the superficies from which the light reflects to be diversly order'd in respect of reflexi∣on,

it must of necessity follow, that it will have a divers lustre and sight: as we see by experience in the necks of Pigeons, and in certain positions of our eye; in which the light, passing through our eye-brows, makes an appearance, as though we saw divers colours streaming from a candle we look upon. And ac∣cordingly we may observe, how some things, or rather most, appear of a colour more inclining to white, when they are ir∣radiated with a great light, then when they stand in a lesser. And we see Painters heighten their colours, and make them appear lighter, by placing deep shadows by them; even so much, that they will make objects appear nearer and further off, meerly by their mixtion of their colours: Because objects, the nearer they are, the more strongly and lively they reflect light, and therfore appear the clearer, as the others do more dusky.

Wherfore, if we put the superficies of one body to have a * 1.282 better disposition for the reflection of light, then another hath; we cannot but conceive, that such difference in the superficies must needs beget variety of permanent colours in the bodies: and, according as the superficies of the same body is better or worse disposed to reflection of light, by polish∣ing, or by compressure together, or the like; so, the same body, remaining the same in substance, will shew it self of a different colour. And, it being evident, that white (which is the chiefest colour) reflects most light, and as evident, that black reflects least light (so that it reflects shadows in lieu of colours, as the Obsidian stone among the Romanes witness), as also, that, to be dense and hard and of small parts is the disposition of the object which is most apt to reflect light: we cannot doubt, but that white is that disposition of the superficies. That is to say, It is the superficies of a body consisting of dense, of hard, and of small parts; and on the con∣trary side, black is the disposition of the superficies, which is most soft and full of greatest pores: for, when light meets with such a superficies, it gets easily into it; and is there as it were ab∣sorpt and hidden in caves, and comes not out again to reflect towards our eye.

This doctrine of ours, of the Generation of Colours, agrees

exactly with Aristotles principles; and follows evidently out of his definitions of Light, and of Colours. (And, for suming up * 1.283 the general sentiments of mankinde, in making his Logical defi∣nitions; I think none will deny his being the greatest Master that ever was). He defines Light to be actus Diaphani; which we may thus explicate: It is that thing which makes a body, that hath an aptitude or capacity of being seen quite through in eve∣ry interior part of it, to be actually seen quite through, accor∣ding to that capacity of it. And he defines Colours to be: The term or ending of a diaphanous body: the meaning wherof is, That Colour is a thing which makes a diaphanous body reach no further, or, the cause why a body is no further diaphanous, then till where it begins; or, that Colour is the reason why we can see no further, then to such a degree, through or into such a body.

Which definition fits most exactly with the thing it gives us the nature of. For, 'tis evident that, when we see a body, the body we see hinders us from seeing any other, that is in a straight line beyond it: and therfore, it cannot be denied, but that Colour terminates and ends the diaphaneity of a body by making it self be seen. And, all men agree in conceiving this to be the nature of Colour; and that it is a certain dis∣position of a body, wherby that body comes to be seen. On the other side, nothing is more evident, then that, to have us see a body, light must reach from that body to our eye. Then, adding to this what Aristotle teaches concerning the producton of seeing; which, he sayes, is made by the action of the seen body upon our sense: it follows, that the object must work upon our sense, either by light, or at least with light; for, light rebounding from the object round about by straight lines some part of it must needs come fom the object to our eye. Therfore, by how much an object sends more light to our eye, by so much that object works more up∣on it.

Now, seeing that divers objects send light in divers man∣ners to our eye, according to the divers natures of those objects in regard of hardness, density, and littleness of parts: we must agree, that such bodies work diversly, and make dif∣ferent motions or impressions upon our eye; and consequent∣ly,

the passion of our eye from such objects must be divers. But, there is no other diversity of passion in the eye from the object, in regard of seeing, but that the object appear divers to us in point of Colour. Therfore we must conclude, That divers bodies (I mean divers or different, in that kind we hear talk of) must necessarily seem to be of divers colours, meerly by the sending of light to our eye in divers fashions. Nay, the very same object must appear of different colours, whenever it hap∣pens that it reflects light differently to us. As we see in Cloth, if it be gather'd together in foulds, the bottoms of those foulds shew to be of one kind of colour; and the tops of them, or where the cloth is stretch'd out to the full percussion of light, appears to be of another much brighter colour: And ac∣cordingly, Painters are fain to use almost opposite colours to express them. In like manner, if you look upon two pieces of the same cloth, or plush, whose grains lie contrariwise to one another, they will likewise appear to be of different co∣lours. Both which accidents, and many other like them in begetting various representations of Colours arise out of lights being more or less reflected from one part then from another.

Thus then you see, how Colour is nothing else, but the dispo∣sition of the bodies superficies, as it is more or less apt to reflect * 1.284 light; since, the reflection of light is made from the superficies of the seen body, and the variety of its reflection begets vari∣ety of colours. But, a superficies is more or less apt to reflect light; according to the degrees of its being more or less pe∣netrable by the force of light striking upon it. For, the rays of light, that gain no entrance into a body they are darted upon, must of necessity fly back again from it. But, if light gets en∣trance and penetrates into the body, it either passes quite through it, or else it is swallow'd up and lost in that body: The former constitutes a diaphanous body, as we have already de∣termin'd; and the semblance which the latter will have, in re∣gard of colour, we have also shew'd must be black.

But, let us proceed a little further. We know that two things render a body penetrable, or easie to admit another bo∣dy into it; Holes (such as we call pores), and softness or humidi∣ty; so that driness, hardness, and compactedness, must be pro∣properties

which render a body impenetrable. And accordingly we see, that, if a diaphanous body (which suffers light to run through it) be much compress'd beyond what it was (as, when water is compress'd into ice), it becomes more visible, that is, reflects more light; and consequently, it becomes more white: for, white is that which reflects more light.

On the contrary side, softness, unctuousness, and viscous∣ness, encreases blackness. As you may experience, in oyling or greasing of Wood which before was but brown; for therby it becomes more black; by reason that the unctuous parts, ad∣ded to the other, more easily, then they single, admit into them the light that sticks upon them; and, when it is gotten in, it is so entangled there (as though the wings of it were bird∣limed over), that it cannot flie out again. And thus it is evi∣dent, how the origine of all colours in bodies is plainly deduced out of the various degrees of rarity and density, variously mix∣ed and compounded.

Likewise, out of this discourse, the reason is obvious, why some bodies are diaphanous and others are opacous: for since * 1.285 it falls out in the constitution of bodies, that one is composed of greater parts then another; it must needs happen that light be more hindred in passing through a body composed of bigger parts, then another whose parts are less. Neither doth it im∣port that the pores be supposed as great as the parts; for, be they never so large, the corners of the thick parts they belong to must needs break the course of what will not bow, but goes all in straight lines, more then if the parts and pores were both less; since, for so subtile a piercer as light, no pores can be too little to give it entrance. 'Tis true, such great ones would better admit a liquid body into them; such a one as wa∣ter or air; but the reason of that is, because they will bow and take any ply, to creep into those cavities, if they be large e∣nough; which light will not do.

Therefore 'tis clear, That freedom of passage can happen to light, only there, where there is an extreme great multitude of pores and parts, in a very little quantity or bulk of body (which pores and parts must consequently, be extreme little ones); for, by reason of their multitude, there must be great variety in their situation: from whence it will happen, that

many lines must be all of pores quite through, and many o∣thers all of parts; although the most will be mixed of both pores and parts. And so we see that, although the light pass quite through in many places, yet it reflects from more; not onely in the superficies, but in the very body it self of the Dia∣phanous substance. But, in another substance of great parts and pores, there can be but few whole lines of pores, by which the light may pass from the object, to make it be seen; and con∣sequently it must be Opacous: which is the contrary of Diaphanous, that admits many Rays of Light to passe through it from the Object to the Eye; wherby It is seen, though the Diaphanous hard body intervene between them.

Now, if we consider the generation of these two Colours * 1.286 (White and black) in bodies, we shall find that likewise to ju∣stifie and second our doctrine. For, white things are generally cold and dry: and therfore are by nature ordain'd to be re∣ceptacles and conservers of heat, and of moisture; as Physi∣tians note. Contrariwise, Black, as also green, (which is near of kin to black) are growing colours, and are the die of heat incorporated in abundance of wet; as we see in smoak, in pit∣coal, in garden ground, and in Chymical putrefactions, all which are black; as also in young herbs; which are generally green as long as they are young and growing. The other co∣lours, keeping their standing betwixt these, are generated by the mixture of them; and, according as they partake more or less of either of them, are nearer or further off from it.

So that, after all this discourse, we may conclude in short, that The colour of a body is nothing else, but the power which that body hath of reflecting light to the eye, in a certain order and position: and consequently, is nothing else but the very superficies of it, with its asperity or smoothness, with its pores or inequalities, with its hardness or softness; and such like. The Rules and limits wherof, if they were duly observ'd and order'd, the whole nature and science of colours would easily be known and described. But, out of this little we have deliver'd of this subject, it may be rightly inser'd, that Real Colours proceed from Rarity and Density (as even now we touch'd), and have their head & spring there: and are not strange

qualities in the air, but tractable bodies on the earth, as all are, which as yet we have found and medled withal, and are, indeed, the very bodies themselves, causing such effects upon our eye by reflecting of light, which we express by the names of Colours.

CHAP. XXX. Of Luminous or apparent Colours.

AS for the Luminous Colours, whose natures, Art hath * 1.287 made more maniable by us, than those which are called real Colours, and are permanent in bodies: their ge∣neration is clearly to be seen, in the Prism or Triangular glass, we formerly mention'd. The considering of which will confirm our doctrine, That even the colours of bodies are but various mixtures of light and shadows, diversly refle∣cted to our eyes. For the right understanding of them, we are to note, That this glass makes apparitions of colours in two sorts: one, when looking through it there appear various colours in the objects you look on (different from their real ones), according to the position you hold the glass in when you look on them. The other sort is, when the beams of light that pass through the Glass are, as it were, tincted in their passage: and are cast by the Glass upon some solid ob∣ject, and appear there in such and such colours; which con∣tinue still the same, in what position soever you stand to look upon them, either before or behind, or on any side of the Glass.

Secondly, we are to note, that these colours are generally made by refraction (though somtimes it may happen otherwise, as * 1.288 above we have mention'd). To discover the reason of the first sort of colours that appear by refraction when one looks through the glass; let us suppose two several bodies, one black, the other white, lying close by one another, and in the same horisontal parallel, but so, that that the black be further from us then the white; then, if we hold the Prism, through which we are to see these two oppositely coloured bodies, som∣what

above them, and that side of it, at which the coloured bo∣dies must enter into the glass to come to our eye, parallel to those bodies; 'tis evident, That the black will come into the Prism by lesser angles then the white. I mean, that in the line of distance from that face of the glass at which the co∣lours come in, a longer line or part of black will subtend an angle, no bigger then a lesser line or part of white doth sub∣tend.

Thirdly, we are to note, That, from the same point of the ob∣ject, there come various beams of light to that whole superficies * 1.289 of the glass; so that it may, and somtimes doth happen, that, from the some part of the object, beams are reflected to the eye from several parts of that superficies of the glass at which they enter. And, whenever this happens, the object must ne∣cessarily be seen in divers parts; that is, the picture of it will at the same time appear to the eye in divers places. And particularly, we may plainly observe two pictures; one a lively and strong one, the other a faint and dim one. Of which, the dim one will appear nearer us then the lively one, and is caus'd by a secondary ray; or rather, I should say, by a longer ray, that, striking nearer to the hither edge of the glasses superficies (which is the furthest from the object), makes a more acute angle then a shorter ray doth, that strikes upon a part of the glass further from our eye, but nearer the object: and therfore, the image made by this secondary or longer ray must appear both nearer and more dusky, then the image made by the primary and shor∣ter ray. And, the further from the object that the glass through which it reflects is situated, (keeping still in the same parallel to the Horizon), the further the place where the second dusky picture appears is, from the place where the primary strong picture appears.

If any man have a mind to satisfie himself by experience of the truth of this note, let him place a sheet of white paper upon a black carpet covering a table, so as the paper may reach within two or three fingers of the edge of the capet, (under which, let there be nothing to succeed the black of the carpet, but the empty dusky Ayre); and then let him set himself at a con∣venient distance, (the measure of which is, that the paper ap∣pear at his feet, when he looks through the glass), and

look at the paper through his Prism, situated in such sort as we have above determin'd: and he will perceive a whitish or light∣some shadow proceed from the lively picture that he sees of white, and shoot out neerer towards him then that lively picture is; and he'll discern that it comes into the glass, through a part of it neerer to his eye or face, and further from the object then the strong Image of the white doth. And further, if he causes the neerer part of the paper to he cover'd with some thin body of a sadder colour; this dim white vanishes: which it doth not if the further part of the paper be cover'd. Wherby it is evident, that it is a secondary image, proceeding from the hither part of the paper.

Now then, to make use of what we have said, towards finding out the reason, why the red, and blew, and other colours appear, * 1.290 when one looks through a Prism: let us proceed upon our for∣mer example, in which a white paper lyes upon a black car∣pet (for, the diametral opposition of those colours makes them most remarkable) so that there be a parcel of black on the hither side of the paper; and therin let us examine, accor∣ding to our grounds, what colours must appear at both ends of the Paper, looking upon them through the triangular glass.

To begin with the furthest end, where the black lyes be∣yond the white: we may consider, there must come from the black a secondary dark misty shadow (besides the strong black that appears beyond the paper), which must shoot towards you (in such sort as we said of the whitish lightsome shadow); and consequently, must lye over the strong picture of the white paper. Now in this case, a third midling colour must result, out of the mixture of these two extremes of black and white: since they come to the eye almost in the same line; at least in lines that make so little a difference in their angles, as is not discernable.

The like wherof happens in Cloaths, or Stuffs, or Stockings, that are woven of divers colour'd, but very small threds. For if you stand so far off from such a piece of Stuff, that the little threds of different colours, which lie immediate to one another, may come together as in one line to your eye; it will appear of a midling colour, different from both those it

results from: But, if you stand so near, that each thred sends Rays enough to your eye, and that the Basis of the Triangle, which comes from each Thred to your eye, be long enough to make, at the vertex of it (which is in your eye), an angle big enough to be seen singly by it self; then each colour will ap∣pear apart, as it truly is.

Now, the various natures of midling colours we may learn of Painters; who compose them upon their Pallets by a like mix∣ture of the extreams. And they tell us that, if a white colour prevail strongly over a dark colour, Reds and Yellows result out of that mixture: but if black prevail strongly over white, then blews, violets, and sea-greens are made. And accordingly, in our case we cannot doubt but that the primary lively picture of the white must prevail over the faint dusky sable mantle, with which it comes mingled to the eye: and doing so, it must needs make a like appearance as the Sun-beams do, when, reflecting from a black cloud, they fringe the edges of it, with Red and with Yellow; and the like they do, looking through a rainy or a windy cloud: and, much like hereto, we shall see this mixture of strong white with a faint shaddow of black, make, at this brim of the Paper, a fair ledge of Red; which will end and vanish in a more lightsome one of Yellow.

But at the hither edge of the paper, where the secondary weak picture of white is mingled with the strong black picture, in this mixture the black is prevalent; and accordingly (as we said of the mixture of the Painters colours) there must appear, at the bottom of the paper, a Lemb of deep blew: which will grow more and more lightsome, the higher it grows; and so pas∣sing through violet & sea-green, vanish in light, when it reaches to the mastering field of primary whiteness, that sends his stron∣ger Rays by direct lines. And this transposition of the colours, at the several ends of the paper, shews the reason why they ap∣pear quite contrary, if you put a black paper upon a white Carpet: And therefore, we need not add any thing particu∣larly concerning that.

And likewise, out of this we may understand why the co∣lours appear quite contrary (that is, Red, where before the blew appear'd, and blew, where Red), if we look upon the same

object through the Glass in another position or situation of it; namely, if we raise it so high, that we must look upwards to see * 1.291 the object: which therby appears above us; wheras, in the for∣mer situation, it came in through the lower superficies, and we look'd down to it, and it appear'd under us. For, in this se∣cond case, the objects coming into the glass by a superficies, not parallel as before, but sloaping from the object-wards: it fol∣lows, that, the nearer the object is, the lesser must the angle be which it makes with the superficies; contrary to what happened in the former case. And likewise, that, if, from one point of the nearer object, there fall two rays upon the glass, the ray that falls uppermost will make a lesser angle, then the other that falls lower: and so, by our former discourse, that point may come to appear in the same place with a point of the fur∣ther object, and therby make a midling colour.

So that, in this case, the white which is nearer will mingle his feeble picture with the black that is further off: whereas be∣fore, the black that was further off mingled his feeble shadow with the strong picture of the nearer white. Wherfore, by our rule we borrow'd of the Painters, there will now appear a blew on the further end of the paper, where before appeared a red; and by consequence, on the nearer end a red will now ap∣pear, where in the former case a blew appear'd. This case we have chosen, as the plainest to shew the nature of such colours; out of which he that is curious may derive his knowledge to o∣ther cases; which we omit, because our intent is only to give a general doctrine, and and not the particulars of the Science; and rather to take away admiration, than to instruct the Reader in this matter.

As for the various colours, which are made by straining light through a glass, or through some other Diaphanous body; to * 1.292 discover the causes and variety of them, we must examine what things they are that concur to the making of them; and what accidents may arrive to those things, to vary their product. 'Tis clear, that nothing intervenes or concurs to the producing of any of these colours; besides the light it self which is dyed into colour, and the glass or Diaphanous body through which it passes. In them therfore, and in nothing else, we are to make our enquiry.

To begin then: we may observe, that light, passing through a Prism, and being cast upon a reflecting object, is not alwayes colour; but in some circumstances it still continues light, and in others it becomes colour. Withal we may observe, that those beams which continue light and endure very little muta∣tion by their passage, making as many refractions, make much greater deflexions from the straight lines by which they came, into the glass, then those Rays do which turn to colour. As you may experience, if you oppose one surface of the Glass Perpendicularly to a Candle, and set a Paper (not irradiated by the Candle) opposite to one of the other sides of the Glass: for, upon the paper, you shall see fair light shine without any colour, and you may perceive, that the line, by which the light comes to the Paper, is almost Perpendicular to that line by which the light comes to the Prism. But, when light be∣comes colour, it strikes very obliquely upon one side of the glass; and comes likewise very obliquely out of the other, that sends it in colour upon a reflectent body; so that in conclusion, there is nothing left us whereon to ground the generation of such colours; besides the littleness of the angle, and the sloap∣ingness of the line, by which the illuminant strikes one side of the Glass and comes out at the other, when colours proceed from such a percussion.

To this then we must wholly apply our selves, and knowing that generally, when light falls upon a body with so great a sloaping or inclination, so much of it as gets through must needs be weak and much diffused; it follows, that the reason of such colours must necessarily consist in this diffusion and weakness of light; which the more it is diffused, the weaker it grows, and the more lines of darkness are between the lines of light, and mingle themselvs with them.

To confirm this, you may observe, how, just at the egress, from the Prism, of that light, which going on a little further, be∣comes colours, no colour at all appears upon a paper oppo∣sed close to the side of the Glass; till removing it farther off, the colours begin to shew themselvs upon the edges: therby convincing manifestly, that it was the excess of light, which hindred them from appearing at the first. And, in like manner, if you put a burning glass between the light and the Prism,

so as to multiply the light which goes through the Prism to the paper; you destroy much of the colour, by converting it into light. But on the otherside, if you thicken the air, and make it dusky with smoak or dust; you will plainly see, that, where the light comes through a convex glass (perpendicularly op∣posed to the illuminant), there will appear colours on the edges of the cones that the light makes. And peradventure the whole cones would appear colour'd, if the darkning were con∣veniently made for, if an opacous body be set within either of the cones, its sides will appear colour'd, though the air be but moderately thickned; which shews that the addition of a little darkness would make that, which otherwise appears pure light, be throughly dyed into Colours. And thus you have the true and adequate cause of the appearance of such colours.

Now, to understand what colours, and upon which sides, will * 1.293 appear: we may consider, that, When light passes through a glass or other Diaphanous body, so much of it as shines in the air, or upon some reflecting body bigger then it self, after its passage through the glass, must of necessity have darkness on both sides of it, and so be comprised and limited by two dark∣nesses; but if some opacous body less then the light be put in the way of the light, then it may happen contrariwise, that there be darkness (or the shadow of that opacous body) between two lights.

Again, we must consider, that, when light falls so upon a Prism as to make colours, the two outward Rays, which pro∣ceed from the light to the two sides of the superficies at which the light enters, are so refracted, that, at their coming out again through the other superficies, that Ray which made the less angle with the outward superficies of the glass, going in, makes the greater angle with the outside of the other super∣ficies, coming out; and contrariwise, that Ray, which made the greater angle, going in, makes the lesser, at its coming out: and the two internal angles, made by those two Rays and the outside of the superficies they issue at, are greater then two right angles. And so we see, that the light dilates it self at its coming out.

Now, because Rays that issue through a superficies, the nearer

they are to be perpendiculars to that superficies, so much the thicker they are; it follows, that this dilation of light at its coming out of the glass must be made and encrease from that side, where the angle was least at the going in and greatest at the coming out: so that, the nearer to the contrary side you take a part of light, the thinner the light must be there; and contrariwise, the thicker it must be, the nearer it is to the side where the angle at the rays coming out is the greater. Wher∣fore, the strongest light (that is, the place where the light is least mixed with darkness) must be nearer that side than the other. Consequently hereto, if by an opacous body you make a shadow comprehended within this light; that shadow must also have its strongest part nearer to one of the lights betwixt which it is comprised, then to the other: for, shadow being nothing else but the want of light, hindred by some opacous body; it must of necessity lie aversed from the illuminant, just as the light would have lain if it had not been hindred. Wherfore, seeing that the stronger side of light more impeaches the darkness, then the feebler side doth, the deepest dark must incline to that side where the light is weakest; that is, towards that side on which the shadow appears, in respect of the opacous body or of the illuminant; and so be a cause of deepness of Colour on that side, if it happen to be fringed with colour.

CHAP. XXXI. The causes of certain appearances in luminous Colours; with a Conclusion of the discourse touching the Senses and the Sensible Qualities.

OUt of these grounds we are to seek the resolution of all such Symptoms, as appear to us in this kind of colours. * 1.294 First therfore, calling to mind, how we have already de∣clared, that the red colour is made by a greater proportion of light mingled with darkness, and the blew with a less propor∣tion: it must follow, that, when light passes through a glass in such sort as to make colours, the mixture of the light and dark∣ness, on that side where the light is strongest, will encline to a

red; and their mixture on the otherside, where the light is weakest, will make a violet or blew. And, this we see fall out accordingly, in the light which is tincted by going through a Prism; for, a red colour appears on that side from which the light dilates or encreases, and a blew is on that side towards which it decreases.

Now, if a dark body be placed within this light, so as to have the light come on both sides of it; we shall see the contrary happen, about the borders of the picture or shadow of the dark body: that is to say, the red colour will be on that side of the picture which is towards or over against the blew colour made by the glass, and the blew of the picture will be on that side which is towards the red made by the glass; as you may expe∣rience, if you place a slender opacous body along the Prism, in the way of the light, either before or behind the Prism. The reason wherof is, that the opacous body standing in the middle, environ'd by light, divides it and makes two lights of that which was but one; each of which lights, is comprised be∣tween two darknesses; to wit, between each border of Sha∣dow that joyns to each extreme of the light that comes from the glass, and each side of the Opacous bodies shadow. Wher∣fore in each of these lights, or rather in each of their comixti∣ons with darkness, there must be red on the one side, and blew on the other; according to the course of light which we have explicated.

And thus it falls out, agreeable to the Rule we have given, that blew comes to be on that side of the opacous bodies sha∣dow, on which the glass casts red; and red on that side of it, on which the glass casts blew. Likewise, when light, going through a convex glass makes two cones: the edges of the cone, be∣twixt the glass & the point of concourse, will appear red (if the room be dark enough); and the edges of the further cone will appear blew; both for the reason given. For, in this case, the point of concourse is the strong light betwixt the two cones: of which, that betwixt the glass and the point is the stronger; that, beyond the point, the weaker. And for this very reason, if an opacous body be put in the axis of these two cones, both the sides of its picture will be red, if it be held in the first cone which is next to the glass, and both will be blew, if the body be situated

in the further cone: for, both sides being equally situated to the course of the light, within its own cone, there is nothing to vary the colours, but only the strength and weakness of the two lights of the cones on this & that side the point of the con∣course; which point being, in this case, the strong and clear light, wherof we made general mention in our precedent note, the cone towards the glass and the illuminant is the stronger side, and the cone from the glass is the weaker.

In those cases where this reason is not concern'd, we shall see the victory carried, in the question of colours, by the shady side of the opacous body: that is, the blew colour will still ap∣pear on that side of the opacous bodies shadow that is furthest from the illuminant. But, where both causes concur and contest for precedence, there the course of the light carries it: that is to say, the red will be on that side of the opacous bodies shadow where it is thicker and darker, and blew on the otherside where the shadow is not so strong; although the shadow be cast that way that the red appears: as is to be seen, when a slender body is placed betwixt the Prism and the reflectant body, upon which the light & colours are cast through the Prism. And 'tis evident, that this cause of the course of the shadow is in it self a weaker cause, than the other of the course of light, and must give way to it whenever they incounter (as it cannot be expected but that, in all circumstances, shadows should be light) because the colours which the glass casts in this case, are much more faint and dusky, than in the other.

For effects of this latter cause, we see that, when an opacous body lyes cross the Prism, whiles it stands end-ways, the red or blew colour will appear on the upper or lower side of its pi∣cture; according as the illuminant is higher or lower then the transverse opacous body: the blew ever keeping to that side of the picture, that is furthest from the body and the illuminant that make it; and the red, the contrary. Likewise, if an opacous body be placed out of the axis, in either of the cones we have explicated before; the blew will appear on that side of the pi∣cture which is furthest advanced in the way that the shadow is cast, and the red on the contrary. And so, if the opacous body be placed in the first cone, beside the axis; the red will appear on that side of the picture, in the basis of the second cone, which

is next to the circumference, and the blew on that side next the axis: but if it be placed on one side of the axis in the second cone; then the blew will appear on that side the picture is next the circumference, and the red on that side, which is next the center of the basis of the cone.

There remains yet one difficulty of moment to be determi∣ned: * 1.295 which is Why, when through a glass two colours (namely, blew and red) are cast from a Candle upon a paper or wall; if you put your eye in the place of one of the colours that shines upon the wall, and so that colour comes to shine upon your eye (so that another man who looks upon it will see thot colour plainly upon your eye) nevertheless, you shall see the other colour in the glass? as for example, if on your eye there shines a red, you shall see a blew in the glass; and if a blew shines upon your eye, you shall see a red.

The reason hereof is, that The colours which appear in the glasse are of the nature of those luminous colours we first ex∣plicated, that arise from looking upon white and black bor∣dering together. For, a candle standing in the air, is, as it were, a white situated between two blacks; the circumstant dusky air, having the nature of a black: so then, that side of the candle which is seen through the thicker part of the glass appears red, and that which is seen through the thinner appears blew; in the same manner, as when we look through the glass. Whereas the colours shine contrariwise upon a paper or reflecting ob∣ject; as we have already declared, together with the reasons of both these appearances; each fitted to its proper case of looking through the glass upon the luminous object surrounded with darkness, in the one; and of observing the effect wrought by the same luminous object in some medium, or upon some re∣flectent superficies, in the other.

And to confirm this, if a white paper be set standing hollow before the glass, (like half a hollow pillar, whose flats stands edgeways towards the glass, so as both the edges may be seen through it); the further edge will seem blew, and the nearer will be red, and the like will happen, if the paper be held in the free air parallel to the lower superficies of the glass, without any black carpet to limit both ends of it (which serves to make the colours the smarter. (So that, in both cases, the air serves mani∣festly

for a black; in the first, between the two white edges, and in the second, limiting the two white ends: and by consequence, the air about the candle must likewise serve for two blacks in∣cluding the light candle between them.

Several other delightful experiments of luminous colour I might produce; to confirm the grounds I have laid, for the na∣ture and making of them: But, I conceive, these I have menti∣on'd are abundantly enough, for the end I propose to my self. Therfore, I will take my leave of this subtle and nice sub∣ject; referring my Reader (if he be curious to entertain him∣self with a full variety of such shining wonders) to our inge∣nious Countreyman and my worthy friend, Mr. Hall: who, at my last being at Liege, shew'd me there most of the experiences I have mention'd, together with several other very fine and re∣markable curiosities concerning light; which he promised me he would shortly publish in a work, that he had already cast and almost finished upon that svbject. And in it I doubt not but He will give entire satisfaction to all the doubts and Problems that may occur in this subject: wheras my little exercise formerly in making experiments of this kind, and my less conveniency of attempting any now, makes me content my self with thus spin∣ing a course thred (from wooll carded me by others) that may run through the whole doctrine of colours, whose causes have hitherto been so much admired, and that it will do so, I am strongly perswaded; both because, if I look upon the causes which I have assigned à prirori, me thinks they appear very agreeable to nature and to reason; and if I apply them to the several Pheno∣mens which Mr. Hall shew'd me, and to as many others as I have otherwise met with, I find they agree exactly with them, and render a full account of them.

And thus, you have the whole nature of luminous colours re∣solv'd into the mixion of light and darkness; by the due orde∣ring of which, who have skil therin may produce any middle colour he please: as I my self have seen the experience of in∣finite changes in such sort made; so that it seems to me, nothing can be more manifest, then that luminous colours are generated in the way here deliver'd. Of which how that gentle and obedient Philosophy of Qualities (readily obedient to what hard task soever you assign it) will render a rational

account; and what discreet vertue it will give the same things to produce different colours and maked different appearances, meer∣ly by such nice changes of situation: I do not well understand. But peradventure, the Patrones of it may say that every such circumstance is a Conditio sine qua non: and therwith (no doubt) their Auditors will be much the wiser, in comprehending the particular nature of light, and of the colours that have their origine from it.

The Rainbow, for whose sake most men handle this matter of luminous colours, is generated in the first of the two ways we * 1.296 have deliver'd for the production of such colours: and hath its origine from refraction; when the eye, being at a convenient distance from the refracting body, looks upon it to discern what apears in it. The speculation of which may be found in that excellent discourse of Mounsir des Cartes, which is the sixth of his Meteors: where he hath, with great accurateness, deliver'd a most ingenious doctrine of this mystery; had not his bad chance, of missing in a former principle (as I conceive) somwhat obscu∣red it. For, he there gives the cause, so neat and so justly calcu∣lated to the apearances, as no man can doubt but that he hath found out the true reason of this wonder of nature, which hath perplex'd so many great wits: as may almost be seen with our very eyes; when, looking upon the fresh dew, in a Sunshiny morning, we may, in due positions, perceive the Rainbow co∣lours not three yards distant from us; in which we may distin∣guish even single drops with their effects. But he, having deter∣ned the nature of light to consist in motion, and proceeding con∣sequently, concludes colours to be but certain kinds of motion: by which, I fear, it is impossible that any good account should be given of the experiences we see.

But, what we have already said in that point, I conceive, is sufficient to give the Reader satisfaction therin: and to secure him, that the generation of the colours in the Rain-bow, as well as all other colours, is reduced to the mingling of light and darkness; which is our principal intent to prove. Adding therto, by way of advertisement, for others whose leisure may permit them to make use thereof; that who shall ballance the proportions of luminous colours may, peradventure, make himself a step to judg of the natures of those bodes, which

really and constantly wear like dyes: for, the figures of the least parts of such bodies, joyntly with the connexion or ming∣ling of them with pores, must of necessity be that which makes them reflect light to our eyes, in such proportions, as the lumi∣nous colours of their tincture and semblance do.

For, two things are to be consider'd in bodies, in order to re∣flecting of light: either the extancies and cavities of them or their hardness and softness. As for the first, the proportions of light mingled with darkness will be varied, according as the ex∣tancies or the cavities exceed, and as each of them is great or small: since cavities have the nature of darkness, in respect of extancies; as our modern Astronomers shew, when they give an account of theface (as some call it) in the Orbe of the Moon. Likewise, in regard of soft or of resistent parts; light will be reflected by them more or less strongly, that is, more or less mingled with darkness. For, whereas it rebounds smart∣ly back, if it strikes not upon a hard and a resistent body; and accordingly will shew it self in a bright colour: it must of ne∣cessity not reflect at all, or but very feebly, if it penetrates into a body of much humidity, or loses it self in the pores of it; and that little which comes so weakly from it, must conse∣quently appear of a duskie die. And, these two being all the causes of the great variety of colours we see in bodies; according to the quality of the body in which the real colour appears, it may easily be determined from which of these it proceeds: and then, by the colour, you may judge of the composition and mixture of the rare and dense parts, which by reflecting light begets it.

In fine, out of all we have hitherto said in this Chapter, we may conclude the Primary intent of our so long discourse: which * 1.297 is, That the Senses of Living Creatures, and the Sensible Qua∣lities in Bodies, are made by the Mixtion of Rarity and Density; as well as the Natural Qualities we spoke of in their place. For, it cannot be denied but that heat and cold, and the other cou∣ples or pairs which beat upon our Touch, are the very same as we see in other bodies; the qualities which move our Taste and Smel are manifestly a kin and joyn'd with them; Light we have concluded to be Fire; and of Motion (which affects our ear) ther's no dispute: so that it is evident, how all sensible qua∣qualities

are as truly bodies, as those other Qualities which we call natural.

To this we may add, that the Properties of these sensible qualities are such as proceed evidently from Rarity and Density. For (to omit those which our Touch takes notice of, as too plain to be question'd) Physitians, judg and determine the natural qualities of meat and medicines and simples, by their Tastes and Smels. By those qualities they find out powers in them to do material operations; and such as our instruments of cutting, filling, brushing, and the like, do to ruder and grosser bodies: all which vertues being in these instruments by the different tempers of Rarity and Density is a convincing argument, that it must be the same causes, which produce effects of the same kind in their smel and tastes. And, and as for light, 'tis known how corporeally it works upon our eyes.

Again, if we look particularly into the composition of the organs of our Senses, we shall meet with nothing but such quali∣ties, as we find in the composition of all other natural bodies. If we search into our Eye, we shall discover in it nothing but dia∣phanety, softness, divers colours, and consistencies; which all Anatomists, to explicate, parallel in other bodies: the like is of our Tongue, our Nostrils, and our Ears. As for our Touch, that is so material a sense, and so diffused over the whole body; as we can have no difficulty about it. Seeing then that all the qualities we can discover in the organs of our Senses are made by the various minglings of Rarity with Density; how can we doubt, but that the active powers over these patients must be of the same nature and kind?

Again, seeing that examples above brought convince, That the objects of one sense may be known by another; who can doubt of a community among them, if not of degree, at least of the whole kind? as we see that the Touch is the groundwork of all the rest; and consequently, that being evidently corporeal and consisting in a temper of Rarity & Density, why should we make difficulty in allowing the like of the rest?

Besides, let us compose of Rarity and Density such tempers as we find in our Senses; and let us again compose of Rarity and Density such actors, as we have determined the qualities, we call sensible to be: and will it not manifesty follow, that

these two, applyed to one another, must produce such effects, as we affirm our Senses have; that is, to pass the outward objects, by different degrees, to an inward receiver?

Again, let us cast our eyes upon the natural resolution of * 1.298 bodies, and how they move us; and we shall therby discover, both what the Senses are, and why they are just so many, and that they cannot be more. For, an outward body may move us either in its own bulk or quantity; or as it works upon ano∣ther: The first is done by the Touch; the second by the Ear, when a body, moving the air, makes us take notice of his mo∣tion. Now in resolution, there are three active parts proceed∣ing from a body, which have power to move us: the fiery part; which you sees works upon your eyes, by the virtue of light: the airy part; which we know moves our nostrils, by being suck'd in with the air. And lastly, the salt; which dissolves in water, and so moves our watry sense, which is, our taste.

And, these being all the active parts, that shew themselvs in the resolution of a body; how can we imagine there should be any more senses to be wrought upon? For, what the stable body shews of it self will be reduced to the touch: what as it moves, to hearing: what the resolutions of it, according to the natures of the resolved atomes that fly abroad, will concern the other three senses; as we have declared. And, more ways of working, or of active parts, we cannot conceive to spring out of the na∣ture of a body.

Finally, if we cast our eyes upon the intention of nature: to what purpose are our Senses, but to bring us into knowledge of the natures of the substances we converse withall? Surely, to effect this, there cannot be invented a better or more reason∣able expedient, then to bring to our judgment seat the like∣nesses or extracts of those substances; in so delicate a model, that they may not be offensive or cumbersom; like so many patterns presented to us, to know by them what the whole piece is. (For all similitude is a communication between two things, in that quality wherin their likeness consists). And therfore we cannot doubt, but that nature hath given us, by the means whe have explicated, an essay to all things in the world that fall under our commerce; wherby we judge whether they be profitable or nocive to us: and yet in so delicate and

subtile a quantity, as may, in no way be offensive to us; whiles we take our measures to attract what is good, and avoid what is noxious.

CHAP. XXXII. Of Sensation, or the motion wherby Sense is properly exercised.

OUt of the considerations which we have delivered in these last Chapters, the Reader may gather the unreasonable∣nesse * 1.299 of vulgar Philosophers; who, to explicate life and sense, are not content to give us terms with out explicating them; but will force us to believe contradictions. Telling us, that Life consisted in this, That the same thing hath a power to work upon it self; and that Sensation is a working of the active part of the same sense upon its passive part: and yet will ad∣mit no parts in it; but will have the same indivisible power work upon it self. And this, with such violence and down∣bearing of all opposition, that they deem him not considerable in the Schools, who shall offer only to doubt of what they teach him hereabout; but brand him with the censure of one who knows not, and contradicts the very first principles of Philoso∣phy. Wherefore 'tis requisite we should look somewhat more particularly, into the manner how sensation is made.

Monsir des Cartes, (who, by his great and Heroick Attempts, and by shewing mankind how to steer and husband their rea∣son to best advantage, hath left us no excuse for being ignorant of any thing worth the knowing), explicating the nature of Sense, is of opinion, that the bodies without us, in certain circumstances, give a blow upon our exterior Organes: from whence, by the continuity of the parts, that blow or motion is continued, till it come to our brain and seat of knowledge; up∣on which it gives a stroke, answerable to that which the out∣ward sense first received. And there this knock causing a particular effect according to the particular nature of the mo∣tion (which depends of the nature of the object that produ∣ces it); our soul and mind hath notice, by this means, of every

thing that knocks at our gates: and, by the great variety of knocks or motions that our brain feeles, (which rises from as great a variety of natures in the objects that cause them), we are enabled to judg of the nature and conditions of every thing we converse withal.

As for example; he conceives Light to be nothing else but a percussion made by the illuminant upon the air, or upon the ethereal substance, which he puts to be mixed with, and to run through all bodies: which being a continuate medium be∣tween the illuminant and our sense, the percussion upon that strikes also our sense; which he calls the nerve that reaches from the place strucken (to wit, from the bottom of your eye) to the brain. Now, by reason of the continuity of this string or nerve, he conceives that the blow, made upon the outward end of it by the other, is convei'd by the other end of it to the brain; the end striking the brain in the same measure as the other struck the other end of it: like the Jack of a Virginal, which strikes the sounding cord, according as the Musitians hand presses upon the stop. The part of the brain which is thus strucken he supposes to be the phantasie; where he deems the soul resides; and thereby takes notice of the Motion and Object that are without. And what is said thus of Sight, is to be applyed proportionably to the rest of the Senses.

This then is the summe of Monsir des Cartes his opinion; which he hath very finely expressed, with all the advantages that opposite examples, significant words, and clear method can give to a witty Discourse: Which yet is but a part of the commendations he deserves, for what he hath done on this particular: He is, over and above all this, the first that I have ever met with, who hath published any conceptions of this nature, wherby to make the operations of sense intellegible. Certainly, this praise will ever belong to him, that he hath gi∣ven the first hint of speaking groundingly, and to the purpose, upon this Subject; and, whoever shall carry it any further (as what important Mystery was ever born and perfected at once?) must acknowledge to have derived his light from him.

For my part, I shall so far agree with him, as to allow mo∣tion

alone sufficient to work sensation in us: and not only to allow it sufficient, but also to profess, that, not only this, but no * 1.300 other effect whatever can be wrought in us, but motion, and by means of motion. Which is evident out of what we have already deliver'd, speaking of bodies in general, that all action among them either is local motion, or else follows it; and no less evident, out of what we have declared in particular, concerning the operations of the outward senses, and the ob∣jects that work upon them: and therfore, whoever shall in this matter require any thing further then a difference of motion, he must first seek other instruments in objects to cause it. For, examining from their very origine the natures, of all the bodies we converse withal; we cannot find any ground to believe they have power or means to work any thing beyond motion.

But, I shall crave leave to differ from him, in determining what is the subject of this motion, wherby the brain judges of the nature of the thing that causes it. He will allow no local change of any thing in a man, further then certain vibrations of strings, which he gives the objects to play upon, from the very sense up to the brain: and, by their different manners of shaking the brain, he will have it know what kind of thing it is that strikes the outward sense; without removing any thing within our body from one place to another. But, I shall go the more common way; and make the Spirits to be the porters of all news to the brain: only adding thereto, that these news, which they carry thither, are material participations of the bodies, that work upon the outward organs of the senses, and, passing through them, mingle themselvs with the Spirits, and so go whether they carry them; that is, to the brain, to which, from all parts of the body, they have immediate resort, and a perpetual communication with it.

So that, to exercise Sense (which the Latines call sentire, but in English we have no one word common to our several particular motions of divers perceptions by sense) is, Our brain to receive an impression from the extern object, by the opera∣tion or mediation of an organical part made for that purpose, & some one of those which we term an extern Sense; from which impression usually flows some motion proper to the living crea∣ture.

And thus you see that the outward Senses are not truly Senses, as if the power of sensation were in them: but in ano∣ther meaning; to wit, so far as they are instruments of quali∣fying or conveying the object to the brain.

Now, that the Spirits are the instruments of this convey∣ance * 1.301 is evident, by what we daily see; that, if a man be very at∣tentive to some one extern object (as, to the hearing or see∣ing of somthing that much delights or displeases him), he nei∣ther hears or sees any thing but what his mind is bent upon: though, all that while, his eyes and ears be open; and several of their objects be present, which at other times would affect him. For, what can be the reason of this, but that the brain, em∣ploying the greatest part of his store of Spirits about that one object, which so powerfully entertains him, the other finde very few free for them to imbue with their Tincture? And there∣fore they have not strength enough to give the brain a suffici∣ent taste of themselvs, to make it be observ'd; nor to bring them∣selvs into a place where they may be distinctly discern'd: but, striving to get to it, they lose themselvs in the throng of the others, who for that time besiege the brain closely. Wheras in Monsir des Cartes his way, (in which no spirits are re∣quired), the apprehension must of necessity be carried pre∣cisely according to the force of the motion of the extern ob∣ject.

This argument, I confess, is not so convincing against his opinion, but that the necessity of the consequence may be a∣voided; and another reason be given for this effect, in Monsir des Cartes his doctrime. For he may say, that the affection, be∣ing vehemently bent upon some one object, may cause the mo∣tion to be so violent, by the addition of inward percussions, that the other coming from the outward sense, being weaker, may be drown'd by it: as lesser sounds are by greater, which for∣cibly carry our ears that way, and fill them so entirely that the others cannot get in to be heard, or as the drawing of one man, that pulls backwards, is not felt, when a hundred draw forwards. Yet this is hard to conceive, considering the great eminency which the present object hath over an absent one, to make it self be felt; whence it follws, that multiplication of motion must be extremely encreased wthin, to overtop

and bear down the motion, caused by a present object actual∣ly working without.

But, that which indeed convinces me to believe I go not wrong in this course, which I have set down, for extern bodies working upon our sense and knowledge, is first, the conveni∣ence and agreeablness to nature, both in the objects and in us, that it should be done in that manner: and next, a difficulty in Monsir des Cartes his way, which, me thinks, makes it impos∣sible that his should be true. And then, his being absolutely the best of any I have hitherto met withal, and mine supplying what his falls short in, and being sufficient to perform the ef∣fects we see: I shall not think I do amiss in believing my own to be true, till some body else shew a better.

Let us examine these considerations one after another. 'Tis * 1.302 manifest, by what we have already establish'd, that there is a perpetual flux of little parts or atomes out of all sensible bo∣dies, that are composed of the four Elements, and are here in the sphere of continual motion by action and passion: and such it is, that, in all probability, these little parts cannot chuse but get in at the doors of our bodies, and mingle themselvs with the spirits that are in our nervs. Which if they do, 'tis una∣voidable, but that, of necessity, they must make some motion in the brain; as, by the explication we have made of our outward senses, is manifest: and the brain being the source and origine of all such motion in the Animal, as is term'd voluntary, this stroke of the object will have the power to cause some variati∣on in its motions that are of that nature, and by consequence, must be a Sensation, for, that change, which, being made in the brain by the object, is cause of voluntary motion in the Animal, is that we call sensation.

But, we shall have best satisfaction, by considering how it fares with every sense in particular. 'Tis plain, that our Touch or feeling is affected by the little bodies of heat, or cold, or the like, which are squees'd or evaporated from the object, and get into our flesh, and consequently, mingle themselvs with our spirits: and accordingly, our hand is heated with the flood of subtile fire, which, from a great one without, streams into it; and is benum'd with multitudes of little bodies of cold, that settle in it. All which little bodies, of heat or of

cold or of what kind soever they be, when they are once got in, must needs mingle themselvs with the spirits they meet with in the nerve: and consequently, must go along with them up to the brain. For, the channel of the nerve being so little, that the most accurate Inspectors of nature cannot distinguish any little cavi∣ty or hole running along the substance of it; and the spirits which ebb and flow in those channels being so in infinitely sub∣tile, and in so small a quantity as such channels can contain: 'tis evident, that an atome of insensible bigness is sufficient to imbue the whole length and quantity of spirit that is in one nerve; and that atome, by reason of the subtilty of the liquor it is immers'd in, is, presently and as it were instantly, diffused through the whole substance of it. The source therfore of that liquor being in the brain, it cannot be doubted, but that the force of the ex∣tern object must needs affect the brain, according to the quality of the said atome; that is, give a motion or knock, conformable to its own nature.

As for our Tast, 'tis as plain, that the little parts, pressed out of the body which affects it, mingle themselvs with the liquor that being in the tongue, is continuate to the spirits: and then, by our former argument 'tis evident, they must reach to the brain. And for our Smelling, there is nothing can hinder O∣dors from having immediate passage up to our brain, when by our nose they are once gotten into our head.

In our Hearing, there is a little more difficulty, for Sound be∣ing * 1.303 nothing but a motion of the air which strikes our ear; it may seem more then needs, to send any corporeal substance into the brain: and that it is sufficient, that the vibrations of the outward air, shaking the drum of the Ear, do give a like motion to the air within the ear, that on the inside touches the Tympane; and so this air thus moved shakes and beats up∣on the brain. But this, I conceive, will not serve the turn; for, if there were no more, but an actual motion, in the making of Hearing, I do not see how sounds could be conser∣ved in the Memory; since, of necessity, motion must always reside in some body: which argument we shall press anon a∣gainst Monsir des Cartes his Opinion for the rest of the Senses.

Out of this difficulty, the very inspection of the parts within

the ear seems to lead us. For, had there been nothing neces∣sary besides motion, the very striking of the outward air a∣gainst the Tympanum would have been sufficient, without any other particular and extraordinary organization, to have pro∣duced Sounds, and to have carried their motions up to the brain: as, we see, the head of a Drum brings the motions of the Earth to our Ear, when we lay it therto; as we have for∣merly delivered. But, Anatomists find other Tool and In∣struments, that seem fit to work and forge bodies withal, which we cannot imagine nature made in vain. There is a Hammer and an Anvile: wherof, the Hammer, striking upon, the Anvile, must of necessity beat off such little parts of the brainy streams, as, flying about, light and stick upon the top of the Anvile. These, by the trembling of the air following its course, cannot miss of being carried up to that part of the brain, wherto the air within the ear is driven by the impulse of the found; and, as soon as they have given their knock, they rebound back again into the cells of the brain, fitted for harbors to such winged messengers; where they remain lodged with quietness, till they be call'd for again, to renew the effect with the sound made at first. And the various blows which the Hammer strikes, according to the various vibrations of the Tympanum (to which the Hammer is fasten'd, and ther∣fore is govern'd by its motions), must needs make great dif∣ferences of bignesses, and cause great variety of smartnesses of motion in the little bodies they forge.

The last Sense is of Seeing; whose action we cannot doubt * 1.304 is perform'd by the reflection of light to our eye, from the bodies which we see; and this light comes impregnated with a tincture drawn from the superficies of the object it is reflect∣ed from; that is, it brings along with it several of the little atomes, which of themselvs stream, and it cuts from the bo∣dy it struck upon and rebounds from, and they mingling themselvs with the light, in company of it get into the eye, whose fabrick is fit to gather and unite those species (as you may see by the Anatomy of it). And from the eye, their journey is but a short one to the brain; in which we cannot suspect they should lose their force: considering how o∣thers, that come from organes further off, conserves theirs;

and likewise considering the nature of the optick spirits, which are conceiv'd to be the most refin'd of all that are in mans body.

Now, that light is mingled with such little atomes, issuing out of the bodies from which it is reflected, appears evidently enough, out of what we have said of the nature and operations of fire and light: and it seems confirm'd, by what I have often observ'd in some chambers where people seldom come; which having their windows to the South, so as the Sun lies upon them a great part of the day in his greatest strength, and their cur∣tains being continually drawn over them, the glass becomes dyed very deep of the same colour the Curtain is of. Which can proceed from no other cause, but that the beams which shoot through the glass, being reflected back from the Curtain, take somthing along with them from the superficies of it: which, being of a more solid corpulence then they, is left behind (as it were in the strainer) when they come to press themselves through passages and pores, too little for it to accompany them in; and so those atomes of colour stick upon the glass, which they cannot penetrate.

Another confirmation of it is, that, in certain positions, the Sun, reflecting from strong colours, will cast that very colour upon some other place; as I have often experienced in lively Scarlet, and cloth of some other smart colours: and this, not in that gloating wise, as it makes colours of pure light, but like a true real dye, and so as the colour will appear the same to a man, wherever he stands.

Having thus shew'd, in all our Senses, the conveniency and * 1.305 agreeableness of our opinion with nature; which hath been de∣duced out of the nature of the objects, the nature of our spirits, the nature and situation of our nerves, and lastly from the pro∣perty of our brain: our next consideration shall be, of the difficulty that occurs in Monsir des Cartes his opinion. First, we know not how to reconcile the repugnancies appearing in his position of the motion of the Ether; especiaclly in light. For, that Ethereal substance, being extreme rare, must perforce be either extreme liquid, or extreme brittle: if the first, it cannot choose but bow and be pressed in foulds, and bodies of unequal moti∣ons swiming every where in it; and so 'tis impossible it should bring to the eye any constant apparition of the first mover.

But, let us suppose there were no such general interruptions every where incountring and disturbing the conveyance of the first simple motion: yet how can we conceive that a push given so far off, in so liquid an element, can continue its force so far? We see that the greatest thunders and concussions, which at any time happen among us, cannot drive and impart their impulse the ten thousandth part of the vast distance, which the Sun is removed from our eye; and can we imagine, that a little touch of that luminous body should make an impression upon us, by moving another so extreamly liquid and subtile, as the Ether is supposed; which, like an immense Ocean, tossed with all varieties of motion, lies between it and us?

But, admit there were no difficulty nor repugnance in the me∣dium, to convey to us a stroke made upon it by the Suns mo∣tion: let us at least examine, what kind of motions we must al∣low in the Sun, to cause this effect. Certainly, it must needs be a motion towards us; or else it cannot strike and drive the medi∣um forward, to make it strike upon us. And if it be so, either the Sun must perpetually be coming nearer and nearer to us; or else it must ever and anon be receding backwards, as well as moving forwards. Both which are too chymerical for so great a wit to conceit.

Now, if the Ether be brittle, it must needs reflect upon every rub it meets with in its way; and must be broken and shiver'd by every body that moves across it: and therfore, must al∣ways make an uncertain and most disorderly percussion upon the eye.

Then again; after it is arrived to the sense, 'tis no ways likely it should be convey'd from thence to the brain; or that nature intended such a kind of instrument as a nerve, to con∣tinue a precise determinate motion. For, if you consider how a Lute string, or, any other such medium, conveys a motion made in it; you will find that, to do it well and clearly, it must be stretch'd throughout to its full extent, with a kind of stiff∣ness: whereas our nerves are not straight, but lie crooked in our body; and are very lither, till, upon occasion, spirits coming into them swell them out. Besides, they are bound to slesh, and to other parts of the body; which being cessible, must needs dull the stroke, and not permit it to be carried far. And

lastly, the nerves are subject to be at every turn contracted and dilated, upon their own account, without any relation to the strokes beating upon them from an extern agent: which is, by no means, a convenient disposition for a body, that is to be the porter of any simple motion; which should always lie watching in great quietness, to observe scrupulously and exactly the er∣rand he is to carry. So that, for my part, I cannot conceive na∣ture intended any such effect, by mediation of the sinews.

But Monsir des Cartes endeavours to confirm his opinion, * 1.306 by what uses to fall out in Palsies; when a man looses the strength of moving his hands or other members, nevertheless retains his feeling: which he imputes to the remaining intire of the strings of the nerves, while the spirits are some way de∣fective. To this we may answer, by producing examples of the contrary in some men, who have had the motion of their limbs intire and no ways prejudiced, but no feeling at all quite over their whole case of skin and flesh. As particularly, a ser∣vant, in the Colledge of Physitians in London; whom the learned Harvey (one of his Masters) hath told me was exceed∣ing strong to labour, and very able to carry any necessary burthen, and to remove things dexterously, according to the occasion: and yet he was so void of feeling, that he used to grind his hands against the walls, and against course lumber, when he was employ'd to rummage any; in so much that they would run with blood, through grating of the skin, without his feeling of what occasion'd it.

In our way, the reason of both these conditions of people (the paralytike, and the insensible) is easie to be rendred. For, they proceed out of the diverse disposition of the animal spirits in these parts: which if they thicken too much and become very gross, are not capable of transmitting the subtile messengers of the outward world, to the tribunal of the brain, to judge of them; on the otherside, if they be too subtile, they nei∣ther have, nor give power to swell the skin, and so to draw the muscles to their heads. And surely Monsir des Cartes takes the wrong way, in the reason he gives of the Palsie: for, it proceeds out of abundance of humors, which, clogging the nerves, rendreth them washy, and makes them lose their dry∣ness, and become lither; and consequently, unfit and unable, in

his opinion, for sensation (which requires stiffness) as well as for motion.

Yet besides all these, one difficulty more remains against this doctrine, more insuperable (if I mistake not) then any * 1.307 thing, or altogether we have yet said: which is, how the me∣mory should conserve any thing in it, and represent bodies to us, when our fancy calleth for them; if nothing but motions come into the brain. For 'tis impossible, that, in so divisible a subject as the Spirits, motion should be conserv'd any long time: as we see evidently in the air; through which move a flaming Taper never so swiftly, and, as soon as you set it down, almost in the very instant, the flame of it leaves being driven or shaken on one side, and goes quietly and evenly up its or∣dinary course. Therby shewing, that the motion of the air, which for the time was violent, is all of a sudden quieted and at rest: for otherwise, the flame of the Taper would blaze that way the Air were moved. Assuredly, the bodies, that have power to conserve motion long, must be dry and hard ones, Nor yet can such conserve it very long, after the cause, which made it, ceases from its operation. How then can we imagine, that such a multitude of pure motions, as the memory must be stored withal for the use and service of man, can be kept on foot in his brain, without confusion; and for so long a time as his memory is able to extend to? Consider a lesson plaid upon the Lute or Virginals; and think with your self, what power there is or can be in nature, to conserve this lesson-over conti∣nually playing; and reflect, that if the impressions upon the common fense are nothing else but such things, then they must be actually conserved, always actually moving in our head; to the end they be immediately produced, whenever it pleases our will to call them.

And if peradventure it should be replyed, that 'tis not neces∣sary the motions themselvs should always be conserved in actu∣al being; but 'tis sufficient there be certain causes kept on foot in our heads, which are apt to reduce these motions in∣to act, whenever there is occasion of them: All I shall say here∣to is, That this is merly a voluntary Position, and that there appears no ground for these motions to make and constitute such causes; since we neither meet with any instru∣ments,

nor discover any signs wherby we may be induced to believe or understand any such operation.

It may be urged, that divers sounds are by diseases often∣times made in our ears, and appearances of colours in our fan∣tasie. But first, these colours and sounds are not artificial ones, and disposed and order'd by choice and judgment: for, no story hath mention'd, that, by a disease, any man ever heard twenty verses of Virgil, or an Ode of Horace in his ears; or, that ever any man saw fair pictures in his fansie, by means of a blow givin him upon his eye. And secondly, such colours and sounds, as are objected, are nothing else but (in the first case) the motion of humors in a mans eye, by a blow of upon it; which humours have the virtue of making light, in such sort as we see Sea-water has, when it is clash'd together: and (in the second case) a cold vapour in certain parts of the brain, which causes beatings or motions there; whence proceeds the imitation of sounds: so that these examples nothing advantage that party, thence to infer that the similitudes of objects may be made in the common-sense, without any real bodies reserv'd for that end.

Yet I intend not to exclude Motion from any commerce with the Memory; no more then I have done from Sensation For, I will not only grant, that all our remembring is perform'd by the means of motion; but also acknowledge, (that in men) it is, for the most part, of nothing else but of motion. For, what are words but motion? And words are the chiefest objects of our remembrance. 'Tis true, we can, if we will, remember things in their own shapes, as well as by the words that ex∣press them; but experience tells us, that, in our familiar con∣versation, and the ordinary exercise of our memory, we re∣member and make use of the words, rather then of the things themselvs.

Besides, the impressions that are made upon all our other sense, as well as upon our hearing, are likewise for the most part of thing in motion: as, if we have occasion to make a con∣ception of a Man or of a Horse, we ordinarily conceive him Walking, or Speaking, or eating, or using some motion in time. And, as these impressions are successively made upon the out∣ward Organs; so are they successively carried into the fantasie, &

by like succession, are deliver'd over into the memory; from whence, when they are call'd back again into the phantasie, they move likewise successively. So that in truth, all our memory will be of motion; or at least, of bodies in motion: yet it is not chiefly of motion, but of the things that are moved, unless it be when we remember words; and how those motions frame bodies which move in the brain, we have already touched.

CHAP. XXXIII. Of Memory.

BUt how are these things conserv'd in the brain? And how do they revive in the phantasie the same motions, by which * 1.308 they came in thither at the first? Monsir des Cartes hath put us in hope of an explication: and, where I so happy as to have seen that work of his, which the world of learned men so much longs for; I assure my self, I should herein receive great help and furtherance by it. Although with all, I must profess, I can∣not understand how it is possible, that any determinate motion should long be preserv'd untainted in the brain; where there must be such a multitude of other motions in the way, to mingle with it, and bring all into confusion. One day I hope this Jewel will be exposed to publique view; both to do the Author right, and to instruct the World.

In the mean time, let us see what our own Principles afford us. We have resolv'd, that Sensation is not a pure driving of the animal Spirits, or of some penetrable body in which they swim, against that part of the brain where knowledge resides: but, that it is indeed the driving thither of solid material bodies (exceeding little ones) that come from the Objects them∣selvs. Which position, if it be true, it follows, that these bodies must rebound from thence upon other parts of the brain, where at length they find some vacant Cell, in which they keep their Ranks and Files, in great quiet and order; all such sticking together, and keeping company with one another, that enter'd in together: and there they lye still

and are at rest; till they be stir'd up, either by the natural ap∣petite (which is the ordinary course of Beasts), or by chance, or by the will of the Man in whom they are, upon the occasi∣ons he meets with of searching into them. Any of these three Causes raises them up, and gives them the motion that is pro∣per to them; which is the same with that wherby they came in at the first, (for, as Galilaeus teaches us, every body hath a parti∣cular motion peculiarly proper to it, when nothing diverts it) and then they slide successively through the phantasie, in the same manner as when they presented themselvs to it the first time. After which, if it require them no more, they return gently to their quiet habitation in some other part of the brain; from whence they were call'd and summon'd by the phantasies messengers, the Spirits: but, if it have longer use of them, and would view them better then once passing-through permits; then they are turn'd back again, and lead a new over their course, as often as is requisite; like a Horse, that a Rider paces sundry times along by him that he shews him to, whiles he is attentive to mark every part and motion in him.

But, let us examine a little more particularly, how the Causes * 1.309 we have assign'd raise these bodies that rest in the memory, and bring them to the phantasie. The middlemost of them (namely Chance) needs no looking into; because the prin∣ciples that govern it are uncertain ones: But the first and the last (which are, the Appetite and the Will) have a power (which we will explicate hereafter) of moving the brain and the nerves depending of it, conveniently and agreeably to their disposition. Out of which it follows, that the little simili∣tudes in the caves of the brain wealing and swimming about, (almost in such sort, as you see in the washing of Currants or of Rice, by the winding about and circular turning of of the Cooks hand), divers sorts of bodies go their courses for a pretty while; so that the most ordinary objects cannot choose but present themselves quickly, because there are ma∣ny of them, and are every where scatter'd about: but others that are fewer, are longer ere they come in view; much like as in a pair of Beads, that, containing more little ones then great ones, if you pluck to you the string they all hang

upon, you shall meet with many more of one sort, then of the other.

Now, as soon as the brain hath lighted on any of those it seeks for, it puts as it were a stop upon the motion of that; or at least, it moves it so, that it goes not far away, and is revo∣cable at will, and seems like a bait to draw into the fantasie o∣thers belonging to the same thing, either through similitude of nature, or by their connexion in the impression: and, by this means, hinders other objects, not pertinent to the work the fansie hath in hand, from offering themselves unsea∣sonably in the multitudes that otherwise they would do. But, if the fansie should have mistaken on object for another, by reason of some resemblance they have between themselves; then it shakes again the liquid medium they all float in, and rouse's every species lurking in remotest corners and runs over the whole Beadroul of them: and continues this inquisition and motion, till either it be satisfied with retriving at length what it required, or that it be grown weary with tos∣sing about the multitude of little inhabitants in its numerous empire; and so gives over the search, unwillingly and dis∣pleasedly.

Now, that these things be as we have declared will appear, * 1.310 out of the following considerations. First, we see that things of quite different natures, if they come in together, are remembred together: upon which principle the whole art of memory de∣pendeth. Such things cannot any way be comprised under cer∣tain Heads, nor be link'd together by order and consequence, or by any resemblance to one another: and therfore, all their connexion must be, that, as they came in together into the fan∣tasie, so they remain together in the same place in the memory; and their first coupling must proceed from the action, that bound them together in driving them in together.

Next, we may observe, that, when a man seeks and tum∣bles in his memory for any thing he would retrive, he hath first some common and confused notion of it; and somtimes he hath a kind of flasking or fading likeness of it, much like as when, in striving to remember a Name, men use to say, it is at their tongues end: and this shews, that he attracts those things he desires and hath use of, by the likeness of som∣thing

belonging to them. In like manner, when hunger makes one think of meat, or thirst makes one dream of drink, or in other such occasions, wherin the natural appetite stirs objects in the memory and brings them to the fantasie; 'tis manifest, that the spirits informing the brain of the defect and pain which several parts of the body do endure for want of their due nourishment, it gives a motion to the heart, which sends other spirits up to supply the brain, for what service it will order them: by which the brain being fortified, it follows the pur∣suit of what, the living creature is in want of; till the distem∣per'd parts be reduced into their due state, by a more solid en∣joying of it.

Now, why objects drawn out of the memory use to appear * 1.311 in the fantasie, with all the same circumstances which accom∣panied them, at the time when the sense sent them thither, (as when, in remembrance of a friend, we consider him in some place, and at a certain time, and doing some determi∣nate action) the reason is, that the same body, being in the same medium, must necessarily have the same kind of motion; and so consequently, must make the same impression upon the same subject. The medium which these bodies move in (that is, the memory) is a liquid vaporous substance, in which they float and swim at liberty.

Now, in such a kind of medium, all the bodies that are of one nature will easily gather together, if nothing disturb them. For as, when a tuned Lute-string is strucken, that string, by communicating a determinate species of vibration to the Air round about it, shakes other strings within the compass of the moved air; not all, of what extent soever, but only such, as by their natural motion would cause like curlings and foulds in the Air, as the other doth (according to what Galileus hath at large declared) even so, when some atome in the brain is moved, all the rest there about, which are apt to be wafted with a like undulation, must needs be moved in chief; and so they moving, whiles the others of different motions, that, having nothing to raise them, either lie quiet or move very little in re∣spect of the former, 'tis no wonder if they assemble together, and (by the proper course of the brain) meet at the common rendezvous of the fantasie.

And, therfore, the more impressions are made from the same object upon the sense, the more participations of it will be * 1.312 gathered together in the memory; and the stronger impres∣sions it will, upon occasion, make in the fantasie: and them∣selvs will be the stronger to resist any cause that shall strive to deface them. For we see that multitude of objects overwhelms the memory; and puts out, or at least makes unprofitable, those that are seldomest thought on. The reason of which is, that they, being little in quantity, because there are but few species of them, can never strike the seat of knowledge, but in company of others; which being more and greater, make the iwpression follow their nature against the lesser: and in tract of time, things seldom thought of grow to have but a maim'd and confused shape in the memory; and at length are quite forgotten. Which happens, because in the liquid medi∣um they are apt to moulder away, if they be not often repair'd; which mouldring and defacing is help'd on by the shocks they receive from other bodies: like as in a Magazin, a thing that were not regarded (but carelesly tumbled up and down to make room for others, and all things were promiscuously thrown upon it) would soon be bruised and crush'd into a mishapen form, and in the end broken all in pieces.

Now, the repairing of any thing in the memory is done, by receiving new impressions from the object: or, in its absence, by thinking strongly of it; which is an assembling and due piec∣ing together of the several particles of bodies, appertaining to the same matter. But, sometimes it happens, that when the right one cannot be found intire, nor all the orderly pieces of it retriv'd with their just correspondence to one another; the fan∣sie makes up a new one in the place of it: which afterwards, upon presence of the object, appears to have been mi∣staken; and yet the memory, till then, keeps quietly and unquestion'dly for the true object, what either the thought or chance, mingling several parts, had patch'd up toge∣ther.

And, from hence, we may discern how the losing or confoun∣ding of ones memory may happen; either by sicknesses, that di∣stemper the spirits in the brain & disorder their motions, or by

some blows on the head, whereby a man is astonied and all things seem to turn round with him. Of all which effects the causes are easie to be found, in these suppositions we have lay'd.

CHAP. XXXIV. Of Voluntary Motion, Natural Faculties, and Passions.

HItherto we have labor'd to convey the Object into the brain: but when it is there, let us see what further effects * 1.313 it causes; and how that action which we call voluntary motion; proceeds from the brain. For the discovery wherof, we are to note, that the Brain is a substance composed of wa∣try parts mingled with earthy ones: which kind of substances we see are usually full of strings; and so, in strong hard Beer, and Vinegar, and other Liquors of the like nature, we see (if they be exposed to the Sun) little long flakes, which make an appearance of Worms or Maggats floating about. The reason wherof is, that some-dry parts of such Liquors are of themselves as it were hairy or sleasy, that is, have little downy parts (such as you see upon the legs of Flies, or upon Caterpillars, or in little locks of wool) by which they ea∣sily catch and stitck to the other little parts of the like nature, that come near them; and if the liquor be moved, (as it is in the boyling of beer, or making of vinegar by the heat of the sun) they become long strings, because the liquor breakes the ties which are cross to its motion: but such as lie along the stream, or rather the bubling up, maintain themselves in unity, and peradventure grow stronger, by the winding or folding of the end of one part with another; and, in their tumbling and rouling still in the same course, the downy hairs are crush'd in, and the body grows long and round, as happens to a lump of dough, or wax, or wool, roul'd a while in one uniform course. And so, (coming to our purpose) we see that the brain, and all that is made of it is stringy; witness the membranes, the flesh, the bones, &c. But, of all the rest, those called fibers are more stringy; and the nerves seem to be but an assembly

of them: for, though the Nervs be but a great multi∣tude of strings lying in a cluster, nevertheless, by the consent of Physicians and Anatomists, they are held to be of the very sub∣stance of the brain, dryed to a firmer consistence, than it is in the head.

This heap of strings (as we may call it) is enclosed in an outside made of membranes; whose frame we need not here display: only we may note, that it is very apt and fit to stretch; &, after stretching, to return again to its own just length. Next, we are to consider, how the brain is of a nature apt to swell and to sink again; even so much that, Fallopius reports, it swells according to the encrease of the Moon: which whether it be true or no, there can be no doubt but that it, being of a substance which is full of skins and strings, is capable of being stretch'd and of swelling, upon light occasions, and of falling or sinking again upon as light; as being easily pene∣trable by vapours and liquors, whose nature it is, to swell and to extend that which they enter into. Out of which it follows, that it must be the nature of the Nerves to do the like; and in∣deed, so much the more, by how much more dry they are, than the brain: for we see that (to a certain measure) drier things are more capable of extention by the ingression of wet, than moist things are; because these are not capable of receiving much more wet into them.

These things being premised, let us imagine that the brain, * 1.314 being first swell'd, afterwards contracts it self; and it must of necessity follow, that, seeing the Nerves are all open to∣wards the brain (though their concavities cannot be discern'd), the spirits and moisture in the brain must needs be press'd in∣to the Nerves: which being already stored with spirits, suf∣ficiently to the proportion of their hard skins, this addition will make them swell and grow hard; as a Balloon doth, which, being competently full of air, hath nevertheless more air press'd into it.

Since therfore, the Masters of Anatomy teach us, that in every muscle there is a nerve, which is spread into a number of little branches along that muscle; it must follow, that, if these little branches be swollen, the flesh likewise of that muscle must also needs be swollen. Now, the muscle having both its ends

fastned, the one in a greater bone, the other in a lesser, and there being least resistance on that part, where the bone is les∣ser and more movable; the swelling of the muscle cannot choose but draw the little bone towards the great one, and by consequence, move that little bone: and this is that, which Philosophers usually call Voluntary motion. For, since our knowledg remains in the brain, whatever is done by knowledg must be done by the brain: and most of what the brain works for the common service of the living creature proceeds also from knowledg: that is from the motion of fansy, which we have express'd.

This matter being thus far declared, we may now enter up∣on * 1.315 the explication of certain effects; which peradventure might have challeng'd room in the precedent Chapter, but indeed could not well be handled without first supposing this last dis∣course: and it is, what is meant by those powers, that are call'd Natural Faculties; which however in their particulars, they be manifold in a living creature, yet, whenever any of them is resolved, it appears to be compounded of some of these five, to wit, the Attractive, the Retentive, the Secretive, the Conco∣ctive, and the Expulsive faculty.

Of which, the Attractive, the Secretive, and the Concoctive * 1.316 seem not to belong to the nervs: for though we may con∣ceive that the part of the Animal turns it self towards the thing which it attracts, nevertheless, that very turning seems not to be done by vertue of the muscles and nervs, but rather in a natural way, as the motion of the heart is perform'd; in such sort as we have formerly declared. As for example, if the stomach, when it is greedy of meat, draws it self up towards the throat; it seems rather to be a kind of dryness and wrapping, (such as we see in bladders or leather, either by fire or cold, which make them shrivel up and grow hard), than a true faculty of the living creature to seek after meat.

Nor need we extend our discourse any further about these three faculties; seeing that we have already declared in com∣mon, how attraction, drying, and mixture of active bodies with passive ones, is perform'd: which needs but applying to these particulars, to explicate fully their nature. As, for example,

if the Kidneys draw the matter of Urine to them out of the Veinet, it may be by any of the following three manners; to wit, either by draught, by wet, or by steam. For, if the serous parts that are in the blood which runs in the Veins, touch some dry parts conformable to their nature, tending towards the Kidneys; they will infallibly adhere more to those dry parts, than to the rest of the blood. Which if they do in so great a quantity, that they reach to other further parts more dry than these, they will leave the first parts to go to the second: and thus by little, and little, will draw a line of Urine from the blood, if the blood abound with it; and, the nearer it comes to the Kidneys, the stronger still the attraction will be.

The like will happen, if the serosity which is in the blood touch some part weted with a like serosity; or where such hath lately passed. For, as we see water will run more easily upon a wet part of a board or a stone, than on a dry one: so you cannot doubt, but that, if the serous part which is mix'd with the blood, light upon a current of its own nature, it will stick more to that, than to the current of the blood; and so part from the blood, to go that way which the current of its own nature goes.

Besides, it cannot be doubted, but that, from the Kidnyes, and from the passages between the Kidneyes and the Veins, in which the blood is convey'd, there arises a steam: whose na∣ture is to incorporate it self with serous matter, out of whose body it hath been extracted. This steam therfore, flying still to the serous blood which passes by, must of necessity precipi∣tate (as I may say) the serous parts of the blood; or rather must filter them out of their main stock: and so will make them run in that current from which it self flows. And thus you see how Attraction and Secretion are made: for, the drawing of the serosity, without drawing the blood, is the part∣ing of the Urine from the blood. And this example, of the Kidneys operation, may be apply'd to the attractions of all the other parts.

Now, the Concoctive faculty (which is the last of the three * 1.317 we took together) consists of two parts: one is, as it were, a drying of the humour which is to be concocted; the other is

a mingling the substance of the vessel in which the humour is concocted, with the humour it self. For as, if you boyl divers kinds of liquors in brass pans, the pans will taint the li∣quor with the quality of the brass; and therfore Physicians forbid the use of such, in the boiling of several medicines: so, much more in a living creatures body there can be no doubt, but that the vessel in which any humour is concocted gives a tincture therto. Now, concoction consisting in these two, 'tis evident what the concoctive vertue is; to wit, heat, and the specifical property of vessel which by heat is mingled with the humour.

There remain yet the Retentive and the Expulsive faculties * 1.318 to be discoursed of; wherof one kind is manifestly belonging to the voluntary motion which we have declared: namely, that retension and that expulsion which we ordinarily make of the gross excrements either of meat, or drink, or of other humours, either from our head, or stomach, or Lungs: for, it is manifestly done, partly by taking in of wind, and partly by compressing of some parts and opening of others; as Galen shews in his curious book de usu partium.

Another kind of Retention and Expulsion, in which we have no sense when it is made, (or if we have, it is of a thing done in us without our will, though peradventure we may voluntarily advance it) is made by the swelling of fibers in certain parts, through the confluence of humours to them (as in our stomach it happens, by the drink and the juice of the meat that is in it): which swelling closes up the passages by which the contained substance should go out (as the moistening of the strings and mouth of a purse almost shuts it); till in some (for example, the stomach after a meal) the humour, being attenuated by little and little, gets out subtilely, and so, leaving less weight in the stomach, the bag, which weighs down lower, than the near∣er Orifice at which the digested meat issues, rises a little. And this rising of it is also further'd by the wrinkling up and shortning of the upper part of the stomach; which still returns into its natural corrugation, as the masse of liquid meat leavs soaking it (which it doth by degrees, still, as more and more goes out) and so what remains fills less place,

and reaches not so high in the stomach. And thus at length, the residue and thicker substance of the meat, after the thinnest is got out in steam and the midling part is boil'd over in liquor, comes to presse and gravitate wholly upon the Ori∣fice of the stomach: which being then help'd by the figure and lying of the rest of the stomach, and its strings and mouth relaxing, by having the juice which swell'd them squeez'd out of them; it opens it self, and gives way to that which lay so heavy upon it to tumble out. In others (for example, in a woman with child) the enclosed substance (retain'd first by such a course of nature as we have set down) breaks it self a passage by force, and opens the orifice at which it is to go out by violence; when all circumstances are ripe according to na∣tures institution.

But yet there is the expulsion made by Physick, that re∣quires * 1.319 a little declaration. 'Tis of five kinds; Vomiting, Purging by Stool, by Urine, Sweating, and Salivation: every one of which seems to consist of two parts; namely, the Disposition of the Thing to be purged, and the Motion of the Nervs or Fibers for the expulsion. As for example, when the Physician gives a Purge, it works two things: one is, to make some certain humour more liquid and purgeable than the rest; the other is, to make the stomach or belly suck or vent this humour. For the first, the property of the Purge must be, to precipitate that humour out of the rest of the blood; or, if it be thick, to dissolve it that it may run easily: For the se∣cond, it ordinarily heats the stomach, and, by that means, causes it to suck out of the veins; and so to draw from all parts of the body. Besides this, it ordinarily fills the belly with wind; which occasions those gripings men feel when they take physick, and is cause of the guts dis∣charging those humours, which otherwise they would retain.

The like of this happens in Salivation; for the humours are by the same means brought to the stomach, and thence sublimed up to be spitten out: as we see in those, who, taking Mercury into their body, either in substance or in smoak or by applica∣tion, do vent cold humours from any part; the Mercury rising from all the body up to the mouth of the patient, as to the helm

of a sublimatory, and the like some say of Tobacco.

As for Vomiting, it is in a manner wholly the operation of the fibers, provoked by the feelling of some inconvenient body; which makes the stomack wrinkle it self, and work and strive to cast out what offends it.

Sweating seems to be caus'd, by the heating of some nitrous body in the stomach: which, being of subtile parts, is by heat dispersed from the middle to the circumference; and carries with it light humours, which turn into water as they come out into the air. And thus you see, in general, and as much as con∣cerns us to declare, what the Natural Faculties are: and this, according to Galen's own mind, who affirms, that these facul∣ties follow the complexion or temper of parts of a mans bo∣dy.

Having explicated how Voluntary motion proceeds from the brain: our next work ought to be, to examine what it is * 1.320 that such an object (as we brought, by means of the senses, into the brain from without) contributes, to make the brain apply it self to work such voluntary motion. To which purpose, we will go a step or two back, to meet the object at its entrance into the sense; and from thence accompany it in all its jour∣ney and motions onwards. The object which strikes at the senses dore and getting in, mingles it self with the spirits it finds there, is either conform and agreeable to the nature and temper of those spirits, or it is not; that is to say, in short, it is either pleasing or displeasing to the living creature: Or it may be a third kind, which, being neither of these, we may term indifferent. In which sort soever the obect affects the sense, the spirits carry it immediately to the brain; unless some distemper, or strong thought, or other accident hin∣der them.

Now, if the object be of the third kind, that is, be indif∣ferent, as soon as it has strucken the brain, it rebounds to the circle of the memory; and there, being speedily join'd to others of its own nature, it finds them annex'd to some pleasing or displeasing thing, or it doth not: if not, in beasts it serves to little use, and, in men, it remains there till it be call'd for; but if, either in its own nature it be pleasing or displeasing, or afterwards in the memory it be∣became

join'd to some pleasing or annoying fellowship, present∣ly the heart is sensible of it. For, the heart being join'd to the brain by straight and large nervs, full of strong spirits which ascend from the heart; 'tis impossible, but that it must have some communication with those motions, which pass in the brain: upon which the heart (or rather the spirits about it) is either dilated or compressed.

And these motions may be either totally of one kind, or moderated and allay'd by the mixture of its contrary: if of the former sort, one of them we call Joy, the other Grief; which continue about the heart (and peradven∣ture oppress it, if they be in the utmost extre∣mity) without sending any due proportion of spirits to the brain, till they settle a little, and grow more mode∣rate.

Now, when these motions are moderate, they immediately send up some abundance of spirits to the brain; which, if they be in a convenient proportion, are by the brain thrust in∣to such nervs as are fit to receive them: and swelling them, they give motion to the muscles and tendons that are fastned to them; and they move the whole body, or what part of it is under command of those nervs, that are thus fill'd and swell'd with spirits by the brain.

If the object was conformable to the living creature, then the brain sends spirits into such nervs as carry the body to it: but if otherwise, it causes a motion of aversion or flight from it. To the cause of this latter we give the name of Fear: and the other, that carries one to the pursuit of the object, we call Hope, Anger, or Audacity, is mixt of both these; for it seeks to avoid an evil by embracing and overcoming it: and pro∣ceeds out of abundance of spirits.

Now, if the proportion of spirits sent from the heart be too great for the brain, it hinders or perverts the due operation, both in man and beast.

All which it will not be amiss to open a little more parti∣cularly: * 1.321 and first, why painful or displeasing objects contract the spirits, and grateful ones, contrariwise, dilate them. It is, because the good of the heart consists in use, that is, in heat and moisture; and 'tis the nature of heat to dilate it self

in moisture; whereas cold and dry things contract the bodies they work on; and such are enemies to the nature of men and beasts. And accordingly, experience, as well as reason, teaches us, that all objects, which be naturally good, are hot and moist, in due proportion to the creature that is affected and pleas'd with them.

Now, the living creature being composed of the same prin∣ciples, as the world round about him is; and the heart, being an abridgment of the whole sensible creature, and besides full of blood, and that very hot: it comes to pass, that if any of these little extracts of the outward world arrive to the hot blood about the heart, it works in this blood such like an ef∣fect, as we see a drop of water falling into a glass of wine, which is presently dispersed into a competent compass of the wine: so that, any little object must needs make a notable motion in the blood about the heart.

This motion, according to the nature of the object, will be either conformable or contrary; unless it be so little a one as no effect will follow of it, and then 'tis of that kind, which a∣bove we call'd indifferent. If the ensuing effect be conna∣tural to the heart, there rises a motion of a certain fume a∣bout the heart, which motion we call Pleasure; and it never fails of accompanying all those motions which are good, as Joy, Love, Hope, and the like: but, if the motion be displeasing, there is likewise a common sense of a heaviness about the heart, which we call Grief: and it is common to Sorrow, Fear, Hate, and the like.

Now, 'tis manifest by experience, that these motions are all different ones, and strike against divers of those parts of of our body which encompass the heart: out of which striking follows, that the spirits sent from the heart, affect the brain diversly, and are by it convey'd into divers nerves; and so set divers members in action. Whence follows, that certain Members are generally moved, upon the motion of such a passion in the heart; especially in beasts, who have a more determinate course of working, than man hath: and if somtimes we see variety even in beasts, upon knowledge of the circumstances we may easily guess at the causes of that variety. The particularities of all

which motions we remit Physicians and Anatomists: ad∣vertising only, that the fume of pleasure, and the heavi∣ness of grief, plainly shew that the first motions participate of Dilatation, and the latter of Compressi∣on.

Thus you see, how, by the senses, a living creature becomes * 1.322 judg of what is good, what bad for him: which operation is perform'd more perfectly in Beasts, and especially in those that live in the free air, remote from humane conversation (for their senses are fresh and untainted, as nature made them); than in Men. Yet without doubt nature has been as favour∣able in this particular, to men, as them; were it not that, with disorder and excess, we corrupt and oppress our senses: as ap∣pears evidently by the Story we have recorded of John of Leige, as also by the ordinary practice of some Hermites in the De∣serts; who by their taste or smell, would presently be inform'd whether the herbs, and roots, and fruits they met with, were good or hurtful for them, though they never before had had trial of them.

Of which excellency of the Senses, there remains in us on∣ly some dim sparks, in those qualities which we call sympathies and antipathies; wherof the reasonss are plain, out of our late discourse: and are nothing else, but a conformity or opposition of a living creature, by some individual property of it, to some body without it; in such sort as its conformity or oppo∣sition to things by its specifical qualities is term'd natubal or against nature. But of this we shall discourse more at large hereafter.

Thus it appears, how the senses are seated in us, principally for the end of moving us to or from objects, that are good for, or hurtful to us. But, though our Reader be content to allow this intent of nature, in our three inferiour senses; yet he may peradventure not be satisfied, how the two more noble ones (the Hearing and the Seeing) cause such motions to or from objects, as are requisite to be in living creatures for the preservation of them: for (may he say) how can a man, by only seeing an object, or by hearing the sound of it, tell what quali∣ties it is imbued with? or, what motion of liking or disliking, can be caus'd in his heart, by his meer receiving the visi∣ble

species of an object at his eyes, or by his ears hearing some noise it makes? And, if there be no such motion there, what should occasion him to prosecute or avoid that object? When he tasts, or smells, or touches a thing, he finds it sweet, or bitter, or stinking, or hot, or cold; and is therwith either plea∣sed or displeased: but, when he only sees or hears it, what li∣king or disliking can he have of it, in order to the preservation of his nature.

The solution of this difficulty may in part appear, out of what we have already said. But, for the most part, the objects of these two nobler senses move us, by being joyn'd in the Me∣mory with some other thing, that either pleas'd or displeas'd some of the other three senses. And from thence it is, that the motion of going to imbrace the object, or aversion from it, immediately proceeds. As, when a dog sees a man that uses to give him meat, the species of the man coming into his fansie calls out of his memory the others which are of the same na∣ture, and are former participations of that man, as well as this fresh one is. but, these are joyn'd with spicies of meat, be∣cause at other times they did use to come in together; and therfore, the meat being a good unto him, and causing him (in the manner we have said) to move towards it, it will follow that the dog will presently move towards that man, and express a contentedness in being with him. And this is the ground of all assuefaction in beasts, and of making them capable of receiving any instructions.

CHAP. XXXV. Of the material instruments of Knowledge and Passion: Of the seve∣ral effects of Passions: Of Pain and Pleasure, and how the vital spirits are sent from the brain into the intended parts of the body, without mistaking their way.

TO conclude this great business, which concerns all * 1.323 the mutations and motions that are made by outward Agents in a living creature, it will not be amiss to take a short and general survey, of the material instruments which

concur to this effect. Wherof the brain being principal, or at least, the first and next of the principals; we may take notice that it contains, towards the middle of its substance, four con∣cavities, as some count them: but in truth, these four are but one great concavity, in which four, as it were, divers rooms may be distinguished. The nether part of these concavities is very unequal, having joyn'd to it a kind of a net, wrought by the entangling of certain little arteries, and of small emanations from a Sinus, which are interwoven together. Besides this, it is full of kernels, which make it yet more uneven.

Now, two rooms of this great concavity are divided by a little body, somwhat like a skin, (though more fryable) which of it self is clear; but there it is somwhat dim'd, by reason that, hanging a little slack, it somwhat shrivels together: and this, Anatomists call, Septum lucidum, or speculum; and 'tis a different body from all the rest that are in the brain. This tran∣sparent body hangs as it were straightwards, from the fore∣head towards the hinder part of the head: and divides the hol∣low of the brain, as far as it reaches, into the right and the left ventricles.

This part seems to me, (after weighing all circumstances and considering all the conveniencies and fitnesses) to be that, and only that, in which the fansie or common sense resides: though Monsir des Cartes has rather chosen a kernel to place it in. The reasons of my assertions are; First, that it is in the middle of the brain, which is the most convenient situation to receive the messages from all our body, that come by nervs, some from before, and some from behind. Secondly, that, with its two sides, it seems conveniently opposed to all such of our senses, as are double; the one of them sending its little messengers or atomes, to give it advertisements on one side, the other on the other side: so that it is capable of receiving impression indifferently from both. Again, by the nature of the body, it seems more fit to receive all differences of mo∣tion, than any other body near it. It is also most conformable to the nature of the eye; which, being our principal outward sense, must needs be in the next degree to that, which is elevated a strain above our outward senses. Fifthly, it is of a singular and peculiar nature; wheras the kernels are many, and all of them of the same

condition, quality, and appearance. Sixthly, it is seated in the ve∣ry hollow of the brain: which of necessity must be the place and receptacle, where the specieses and similitudes of things re∣side; and where they are moved and tumbled up and down, when we think of many things. And lastly, the situation we put our head in, when we think earnestly of any thing, favours this opi∣nion: for then we hang our head forwards, as it were forcing the specieses to settle towards our forehead; that from thence they may rebound, and work upon this diaphanous substance.

This then supposed, let us consider, that the atomes or likenes∣ses of bodies, having given their touch upon this Septum or Spe∣culum, do thence retire back into the concavities, and stick * 1.324 (as by chance it happens) in some of the inequalities they en∣counter with there. But, if some wind or forcible steam should break into these caves, and as it were brush and sweep them o∣ver; it must follow, that these little bodies will loosen themselvs, and begin to play in the vapour which fills this hollow place: and so, floting up and down, come anew to strike and work upon the Speculum or fantasy. Which being also a soluble body, ma∣ny times these atomes, striking on it, carry some little corpo∣real substance from it sticking upon them: whence ensues, that they, returning again with those tinctures or participations of the very substance of the fantasy, make us remember, not on∣ly the objects themselvs, but also that we have thought of them before.

Further, we are to know, that all the nervs of the brain have their beginnings not far from this speculum: of which we shall * 1.325 more particularly consider two, that are call'd the sixth pair or couple; which pair has this singularity, that it begins in a great many little branches, that presently grow together and make two great ones contain'd within one skin. Now this be∣ing the property of a sense (which requires to have many fibers in it; that it may be easily and vigorously strucken, by many parts of the object lighting upon many parts of those little fibers): it gives us to understand, that this sixth couple hath a particular nature, conformable to the nature of an extern sense; and that the Architect who placed it there intended, by the several conduits of it, to give notice to some part they go to, of what passes in the brain. And accor∣dingly

one branch of this nerve reaches to the heart; not only to the Pericardium, as Galen thought, but even to the very substance of the heart it self, as later Anatomists have disco∣ver'd: by which we plainly see how the motion, which the senses make in the Speculum, may be derived down to the heart.

Now therfore let us consider, what effects the motions so convey'd from the brain will work in the heart. First, re∣membring * 1.326 how all that moves the heart is either pain or pleasure (though we do not use to call it pain, but grief, when the evil of sense moves us only by memory, and not by being actually in the sense); and then calling to mind, how pain (as Naturalists teach us) consists in some division of a nerve, (which they call Solutio continui; and must be in a nerve, for that no solution can be the cause of pain without sense, nor sense be without nerves): we may conclude, that the effect which we call pain, is nothing else but a compression. For, although this solution of continuity may seem to be a dila∣tation, yet in truth, it is a compression in the part where the evil is: which happens to it in the same manner as we shew'd (when we spoke of the motion of Restitution) it doth to stiff bodies, that by violence are compress'd and drawn into a lesse capacious figure, than their nature affects; and return into their own state, as soon as the mastring violence leaves them at liberty.

Pleasure, therfore, must be contrary to this, and consist in a moderate dilatation: for, an immoderate one would cause a compression in some adherent parts; and there would become pain. And conformable to this, we experience, that generally they are hard things which breed pain to us, and those which breed pleasure are oily and soft; as meats and odours, which are sweet to the taste and smell, and soft substances, which are grateful to the touch: the excess of all which proves offensive and painful; so that, from the extremity of pleasure, one enters presently upon the confines of pain.

Now then let us consider, how the little similitudes of bo∣dies, which from without come into the fantasy, must of necessity work there, according to their little power, effects

proportionable to what they wrought first in the outward sen∣ses, from whence they were convey'd to the brain. For, the sen∣ses (that is the nervs) and the Septum lucidum, having both of them their origin from the very substance of the brain, and differing only in degrees of purity and refinement; the same ob∣ject must needs work like effects in both, compressing or dila∣ting them proportionaby to one another. Which compression or dilatation is not pain or pleasure, as it is in the outward sense; but as it is reported to the heart: and that, being the seat of all pains or pleasures wrought in other parts, and that (as it were) dies them into those qualities, is not capable of feeling either it self; so that the strokes of any little similitudes upon the fan∣tasie make only compressions or dilatations there, not pains or pleasures.

Now these bodies or similitudes, if they be reverberated from the fantasie or Septum Lucidum upon the little roots of the nervs * 1.327 of the fixt couple, which go to the heart, must needs work there a proportionable impression to what they wrought upon the fansie, either compressing or dilating it; and the heart being extremely passive, by reason of its exceeding tenderness and heat, cannot choose but change its motion, at least in part, if not in whole: and this with relation to two causes; one the dispo∣sition of the heart it self, the other, the vehemency of the stroke.

This change of motion and different beating of the heat is that which properly is called Passion; and is ever accompanied with pleasure or with grief, according to the nature of the im∣pression, that either contracts or dilates the heart and the spi∣rits about it: and is discovered by the beating of the arteries and of the pulse, Conformable wherunto, Physicians tell us, that eve∣ry passion hath a distinct pulse.

The pulses are divided in common, by abundance, or by * 1.328 want of spirits; yet it both kinds, they may have common dis∣ferences: for in abundance, the pulse may be quick or slow, regular or irregular, equal or unequal; and the like may happen in defect of spirits, according to the motions of the heart which are their causes. Again, the object, by being present or further off, makes the stroke greater or lesser, and accordingly, varies the motion of the heart.

Let us then call to mind, how we have formerly declared,

that life consists in heat and humidity; and that these two join'd together make a thing great: and we may conclude that, of necessity, the motion which is most lively must have a great, full, and large stroke, like the even rolling waves of a wide and smooth sea; and not too quick or smart, like the breaches of a narrow Fretum, agitated by tempestuous winds. From this other motions may vary, either by excess, or by deficiency: the first makes the stroke become smart, violent, and thick; the o∣ther slackens it, and makes it grow little, slow, weak, and thin, or seldom.

And if we look into the motions of our heart, we shall see these three differences of them follow three several chief pas∣sions. The first follows the passion of Joy; the second, the pas∣sion of Anger; and the third, the passion of Grief. Nor need we look any further into the causes of the several motions; for we see that Joy and Grief, following the stroke of sense, the one of them must consist in, an oily dilatation, that is, the spirits about the heart must be dilated by a gentle, large, great, and sweet motion, in a moderation between velocity and slowness: the other contrariwise (following the stroke of sense in pain, as the first did in pleasure) must contract the spirits; and conse∣quently, make their motion or stroke become little, and defici∣ent from all the properties we have above set down.

As for Anger, the motion following that passion is, when the abundance of spirits in the heart is a little check'd by the con∣trary stroke of sense, but presently overcomes that opposi∣tion: and then, as we see a hinder'd water, or a man, that sud∣dainly or forcibly brake through what withstood their motion, go on with a greater violence than they did, and as it were pre∣cipitately; so the heart, having overcome the contraction, which the sense made in it, dilates it self with a fury, and makes its motion smart and vehement. Whence also it follows, that the spirits grow hotter than they were: and accordingly, it is often seen, that, in the scoulding of a woman, and in the irritation of a dog, if ever now and then one thwart them and in∣terpose a little opposition, their fury will be so sharpned and heightned, that the woman will be transported beyond all li∣mits of reason, and the dog will be made mad, with nothing else done to him, but angring him at convenient times: and

some men likewise have, by slight oppositions iterated spee∣dily upon them, before their spirits could relent their vehe∣ment motion (and therfore, must still encrease it,), been an∣gred into feavors.

This passion of Anger seems almost to be solitary, on the side of excess beyond joy (which is, as it were the standard and perfection of all passions; as light or whiteness is of all co∣lours): but on the other side, of deficiency, there are several middle passions, which participate more or less of joy and grief. As, particularly, those two famous ones, which govern mans life, Hope and Fear. Concerning which Physicians tell us, that the pulse or beating of Fear is quick, hard, and unequal: to which I conceive we may safely add, that it must also be small and feeble; the perfection of joy decreasing in it on one side, to wit, from greatness and largeness, but not intirely, so that a kind of quickness supplies in part the other defect. Hope, on the other side, is in such sort defective from joy, that neverthe∣less it hath a kind of constancy, and moderate quantity, and re∣gularity in its motion: and therefore is accounted to be the least hurtful of all the passions, and that which more prolongs mans life. And thus you see how those motions, which we call passions; are engender'd in the heart; and what they are.

Let us then in the next place consider, what will follow in the * 1.329 rest of the body, out of these varieties of Passions, once rais'd in the heart, and sent into the brain. 'Tis evident, that, accor∣ding to the nature and quality of these motions, the heart must needs in every one of them void, out of it self into the arteries, a greater or lesser quantity of blood; and that in divers fashions; and the arteries, which lie fittest to receive these sudden egesti∣ons of blood, are those which go into the brain: which course being directly upwards, we cannot doubt, but that it is the hot∣test and subtilest part of the blood, and the fullest of spirits, that flies that way. These spirits then running a long and perplex∣ed journey up and down in the brain, by various meanders and anfractuosities, are there mingled with the humid steam of the brain it self, and therwith cooled; and come at last to smoak at liberty in the hollow ventricles of the brain, by reeking out of the little arterial branches, that weave the plexus choroides or net we spoke of erewhile: and

they, being now grown heavy, fall (by their natural course) into that part or process of the brain, which is called medulla spi∣nalis, or the marrow of the back-bone; which, being beset by the nervs that run through the body, it cannot happen other∣wise, but that these thick'ned and descending spirits must either fall themselvs into those nervs, or else press into them other spi∣rits which are before them, that, without such new force to drive them violently forwards, would have slided down more lei∣surely. Now, this motion being downwards, and meeting with no obstacle, till it arrive to its utmost period that way; the lowest nervs are those, which naturally feel the communicati∣on of these spirits first.

But, 'tis true, if the flowing tide of them be great, and plenti∣ful, all the other nerves will also be so suddenly fill'd upon the filling of the lowermost, that the succession of their swellings, will hardly be perceptible: as a sudden and violent inundation of water seems to rise on the sides of the channel, as it doth at at the Mill-dam; though reason assures us, it must begin there, because there it is first stop't.

On the contrary side, if the spirits be few, they may be in such a proportion, as to fill only the lower nervs, and to communicate little of themselvs to any of the others. And this is the case in the passion of fear: which being stored with fewer spirits, than any other passion that causes a motion in the body, it moves the leggs most; and so carries the animal, that is afraid, with violence from the object that affrights him. Although, in truth, it is a faint hope of escaping, mingled with fear, which begets this motion: for, when fear is single, and at its height, it stops all motion by contracting the spirits, and thence is cal∣led Stupor; as well as grief, for the same reason. And according∣ly we see extreme cowards, in the extremity of their fear, have not the courage to run away no more than to defend or help themselvs by any other motions.

But, if there be more abundance of spirits, then the upper parts are also moved, as well as the leggs; whose motion con∣tributes to defence: but the brain it self and the senses which are in the head, being the first in the course of this floud of spirits that is sent from the heart to the head, 'tis impossible but that some part of them should be press'd into the nervs of those

senses; and so will make the animal vigilant and attentive to the cause of its fear or grief.

But, if the fear be so great, that it contracts all the spirits and quite hinders their motion (as in the case we touch'd a∣bove), then it leaves also the nervs of the senses destitute of spirits; and so, by too strong apprehension of a danger, the a∣nimal neither sees nor apprehends it: but as easily precipi∣tates it self into it, as it happens to avoid it, being meerly go∣vern'd by chance; and may peradventure seem valiant through extremity of fear.

And thus you see, in common, how all the natural operati∣ons of the body follow, by natural consequence, out of the pas∣sions of the mind: without needing to attribute discourse or reason, either to men or beasts, to perform them. Although, at first sight, some of them may appear, to those that look not into their principles and true causes, to flow from a source of intelligence: wheras 'tis evident, by what we have laid open, they all proceed from the due ranging and ordering of quanti∣tative parts, so or so proportioned by rarity and density. And there is no doubt, but, who would follow this search deeply, might certainly retrive the reasons of all those external moti∣ons, which we see, use to accompany the several passions in Men and Beasts. But, for our intent, we have said enough; to shew by what kind of order and course of nature they may be effect∣ed (without confining our selves over scrupulously to every cincumstance that we have touch'd); and to give a hint, wher∣by others, that will make this inquiry their task, may compile an intire and well grounded and intelligible doctrine of this matter.

Only we will add one advertisment more; which is, that these external motions, caused by passion, are of two kinds: for, some of them are, as it were, the beginnings of the actions, which nature intends to have follow out of the passions that cause them; but others are only bare signs of passions that produce them, and are made by the connexion of parts, unne∣cessary for the main action that is to follow out of the passion, with other parts that by the passion are necessarily moved. As for example, when an hungry mans mouth waters at the sight of good meat, it is a kind of beginning of eating, or of prepa∣ration

for eating; for, when we eat, nature draws a moisture into our mouth, to humectate our meat and convey the tast of it into the nervs of the tongue, which are to make report of it to the brain: but, when we laugh, the motion of our face aims at no further end; and follows only by the con∣nexion of those muscles, which draw the face in such a sort, to some inward parts, that are moved by the passion out of which laughing proceeds.

But, we must not leave this subject without some mention of the Diaphragma; into which the other branch of those nervs, * 1.330 that are called of the sixth conjugation, comes: for, the first branch we have said goes into the heart, and carries thither the objects that come into the brain; and this, we shall find, carries back to the brain the passion or motion, which by the object is rais'd in the heart. Concerning this part of our bo∣dy, you are to note, that it is a musculous membrane, which in the middle of it hath a sinewy circle; wherto is fastned the case of the heart, call'd the Pericardium. This Diaphragma is very sensible, receiving its vertue of feeling from the above mention'd branch of the sixth couple of nervs; and, being of a trembling nature, is, by our respiration, kept in continual mo∣on: and flaps, upon all occasions; as a drum head would do, if it were slack and moist, or as a sail would do, that were brought into the wind.

Out of this description of it, 'tis obvious to conceive, that all the changes of motion in the heart must needs be express'd in the Diaphragma. For, the heart beating upon the Pericar∣dium, and the Pericardium being join'd to the Diaphragma; such jogs and vibrations must needs be imprinted and ec∣choed there, as are formed in the heart: which, from thence, cannot chuse but be carried to the brain, by the sixth couple of nervs. And thus it comes about, that we feel and have sen∣sation of all the passions, that are moved in our heart. Which peradventure is the reason, why the Greeks call this part 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, and from it derive the verb 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, that in Latine signifies Sapere, with Us, to Savour or to like; for, by this part of our body, we have a liking of any object, or a motion of inclination towards it: from whence 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉 is derived, by composition of 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉 with 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉; for a prudent man is he, that likes and is

moved to compass wholsom and good things. Which Etymo∣logy of the word seems to me more natural, than from the phrensy, from whence some derive it; because a great distemper or inflammation in the Diaphragma often causes that disease.

Now, because the object is covey'd from the brain to the heart some part of its way, by the same passage as the motion of the heart is re-convey'd back to the brain: it must of necessity follow, that who is more attentive to outward sense, less con∣siders or reflects on his passion; and who is more attentive to observe and be govern'd by what passes in his heart, is less wrought upon by external things. For, if his fantasy draws strongly to it, the emanations from outward agents upon the senses; the stream of those emanations will descend so strongly from the overfill'd fantasy into the heart, that it will hinder the ascent of any fewer and weaker spirits by the same pipe: But, if the current set strongest upwards, from the heart by the Dia∣phragma to the brain; then, it will so fill the pipe by which it ascends, that little of a weaker tide can make a contrary eddy water in the same channel.

And, by this means nature effects a second pleasure or * 1.331 pain in a living creature, which moves it (oftentimes very powerfully) in absence of the primary object: as we may ob∣serve, when, thinking of any pleasing or displeasing action, we find about our heart a motion which entices us to it, or averts us from it. For, as the first pleasure was occasioned, by the stroke which the object, apply'd to the outward sense, made upon the fantasy, (which can judg of nothing without being strucken by it): so, the second pleasure springs from the spirits moved in the heart, by messengers from the brain; which by the Dia∣phragma rebound a stroke back again upon the fantasy. And, from hence it proceeds, that Memory delights or afflicts us: and that we think of past things with sweetness or with remorse: and therby assuefaction is wrought in beasts, as far as the appetitive part contributes therto; to perfect what was be∣gun in their cognoscitive part, by the ingression of corporeal specieses into their fantasy, in order to the same effect, as we * 1.332 have touch'd before.

But now let us examine, how so small a quantity of a body, as comes from an object into our sense, can be the cause of so great

a motion about our heart. To which purpose we are to remem∣ber, that this motion is perform'd in the most subtile and thin substance, that can be imagin'd. They are the vital spirits that do all this work; which are so subtile, so agil, and so hot, that they may in some sort be termed fire. Now, if we reflect how violent fire is; we need not wonder at the suddain and great motion of these passions.

But we must further take notice, that they are not in the greatest excess, but where the living creature hath been long inured and exercised to them, either directly or indirectly: so that they arrive not to that pitch so much out of the power of the agent, as out of the preparation and disposition of the patient. As when cold water hath been often heated by extinguishing red hot irons in it; after some repetitions, a few quenchings will reduce it from cold to boiling, that at the first would scarce have made it lukewarm: and accordingly we see a heart, that for a long time hath loved and vehemently desired enjoying, is transported in a high degree, at the least sight and renuance of strokes from its beloved object; and is as much dejected, upon any the least deprivation of it. For, to such an object the living creature is hurried away, by a force much resem∣bling the gravity or celerity of a dense body, that is set on run∣ing down a steep hill; to which, the only taking away of a weak let or the least stop gives a precipitate course, not out of the force of what is done to it, but out of the force which was formerly in the thing, though for the present it lay there un∣discovered: and so likewise in these cases, the object rather gives the occasion of the violent motion, than the force or power to it.

These things being thus determined, some peradventure may * 1.333 ask, how it comes to pass that the spirits, which cause motion, being sent on their errand by the brain, alwayes hit the right way; and light duly into those very sinews, which move the living creature according as is requisite for its nature? Since all the passages are open, what is it that governs them, so as they never mistake; and the animal is never driven towards harm, in stead of flying from it? Who is their guide in these ob∣scure paths? But, it were to impute ignorance to the Maker, to think that he framed all the passages alike; and so every one of

them promiscuously apt to receive into them all sorts of spirits, however they be moved. And therfore, we may assure our selvs that since, in these diversities of occasions, there are likewise di∣vers kinds of motions from the heart; either there is, proporti∣onable to them, divers kinds of passages fit to receive and enter∣tain the spirits, according to the condition they are in (so as the passages, which are ajusted to one kind of spirits, will not admit any of another nature): orelse, the first motions of liking or di∣sliking in the heart, which (as we have said) cause a swelling or a contradiction of it against this or that part, stops and hinders the entrance of the spirits into some sinews, and opens others, and drives the spirits into them; so as, in the end by a result of a chain of swellings and contractions of several parts succes∣sively one against another, the due motions of prosecution or aversion are brought about.

As, for example, an object that affects the heart with liking, by dilating the spirits about the heart, sends some into the op∣tick nervs, and makes the living creature turn his eye towards it, and keep it steady upon what he desires: as contrariwise, if he dislike and fear it, he naturally turns his eye and head from it. Now, of this motion of the eye and head may depend the run∣ning to the thing, in one case, and the running from it, in the o∣ther: for, the turning of the neck one way may open a passage for the spirits into those sinews which carry the rest of the body towards the object; and the turning of it to the other side may open other sinews, which shall work a contrary effect, and car∣ry the animal from the object. And the moving of those sinews, which at first turn the neck, proceeds from the quality and number of the spirits that ascend from the heart, and from the region of the heart whence they are sent: according to the variety wherof, there are divers sinews fitted to receive them.

To make up which discourse, we call to mind, what we have said a little above; concerning the motions caused in the external parts of the body, by passion moving within: as when Fear ming∣led with hope gives a motion to the legs. Anger to the arms and hands, and all the rest of the body, as wel as to the legs, & all of them, an attention in the outward senses; which neverthelessper∣verts every one of their functions, if the passion be in extremity.

And then surely we may satisfie our selves, that either this, or some way like it, (which I leave to the curious in Anatomy to settle with exactness; for 'tis enough for my intent, to shew in gross, how these operations may be done, without calling in some incomprehensible qualities to our aid) is the course of nature in motions, where no other cause intervenes besides the object working upon the sense: which all the while it doth, it is the office of the eye of fantasie (or common sense) to lie ever open; still watching to observe what warnings the outward senses send to him, that accordingly he may direct and chang the motions of the heart and whole body.

But, if the object make violent impressions upon the sense, * 1.334 and the heart, being then vehemently moved, therupon send abundance of spirits up to the brain; this multitude of spirits, thronging upon the common sense, oppresses it (as we have already said) in such sort, that the notice which the sense gives of particular circumstances cannot prevail to any effect in the brain: and thus, by the misguidance of the heart, the work of nature is disordered. Which when it happens, we express in short, by saying that Passion blinds the creature, in whom such violent and disorderly motions have course: for Passion is nothing else, but a Motion of the Bloud and Spirits about the Heart; and is the preparation or beginning of the Animals working, as we have above particularly displai'd.

And thus you see in common, how the circuit is made from the Object to the Sense, and from it, by the Common sense and Fantasie, to the Heart, and from the heart back again to the brain; which then sets on work those Organs or parts the animal is to make use of in that occasion; and they either bring him to or carry him from the object, that at the first caused all this motion, and in the end becomes the period of it.

CHAP. XXXVI. Of some actions of Beasts, that seem formal acts of reason; as doubting, resolving, inventing.

IN the last Chapter the foundations are laid, and the way is opened for discovering how all operations which pro∣ceed * 1.335 from nature and passion, are perform'd among living creatures: and therfore, I conceive, I have therby sufficiently compli'd with the obligation of my intention; which is but to express and shew in common, how all the actions of sensible bodies may be reduced to local motion and material applicati∣on of one body to another, in a like manner (though in a dif∣ferent degree) as those motions which we see in lifeless bodies: Yet because, among such animals as pass for irrational, there happen some operations of so admirable a strain, as resemble very much the higest effects which proceed from a man: I think it not a miss, to give some further light, by extending my discourse to some more particulars, than hitherto I have done; wherby the course and way, how they are performed, may be more clearly and easily look'd into. And the rather, be∣cause I have met with some men, who (either wanting pati∣ence to bestow▪ on thoughts of this kind, so much time as is ne∣cessary for the due scanning of them, or else, through a promp∣titude of nature, passing swiftly, from the effect they look upon in gross, to the most obvious seeming cause) suddenly and strongly resolve, that beasts use discourse upon occasions, and are endued with reason.

Yet I intend not here to run through all the several species of their operations, for that were to write the history of every particular animal; but will content my self with touching the causes in common: yet in such sort, that the indifferent Reader may be satisfied of a possibility, that these effects may proceed from material causes; and that I have pointed out the way to those who are more curious, and have the patience and lea∣sure to observe diligently what passes among beasts, how they may trace these effects from step to step, till at length they dis∣cover their true causes.

To begin then. I concieve we may reduce all those actions of Beasts, which seem admirable and above the reach of an ir∣rational animal, to three or four several heads. The first may be of such, as seem to be the very practice of reason; as doubt∣ing, resolving, inventing, and the like. The next shall be of such, as, by docility or practice, beasts oftentimes arrive to. In the third place, we will consider certain continuate actions of a long tract of time; so orderly perform'd by them, as that dis∣course and rational knowledge seem clearly to shine through them. And lastly, we will cast our eye upon some others, which seem to be even above the reason that is in man himself; as, the knowing of things which the sense never had impressi∣on of before, a prescience of future events, providences, and the like.

As for the first, the doubting of Beasts, and their long wa∣vering somtimes between objects that draw them several ways, * 1.336 and at last their resolving, upon some one of them, and their steady pursuance of that afterwards; these will not be matter of hard digestion to him, that shall have well relished & meditated on the contents of the last Chapter. For, 'tis evident, that, if several objects of different natures at the same time present themselvs to a living creature, they must of necessity make divers impressions in the heart of it, proportionable to the causes from whence they proceed: so that, if one of them be a motion of hope, and the other of fear, it cannot choose but follow thence, that what one of them begins, the other will presently break off. By which means it will come to pass, that, in the Beasts heart, there must needs be such waverings as we may observe in the Sea, when, at the beginning of a tide of flood, it meets with a bank that checks the coming in of the waves, and, for a while bears them back as fast as they press upon it: they offer at getting over it, and by and by retire back again from the steepness of it, as though they were apprehen∣sive of some danger on the other side; and then again attempt it afresh, and thus continue labouring, one while one way, an∣other while another; till, at length the floud increasing, the water seems to grow bolder, and breaks amain over the banks, and then flows on till it meets with another that re∣sists it, as the first did. And thus you see, how the Sea can

doubt and resolve, without any discoursing. In like manner it fares with the heart of a Beast (whose motions steer the rest of the body), when it beats betwen hope and fear, or be∣tween any other two contrary passions; without requiring any other principles from whence to deduce it, than those we have already explicated.

But now to speak of their invention: I must confess that, among several of them, there appears so much cunning in laying of their plots (which when they have compassed, they seem to grow careless and unbend their intention, as having ob∣tain'd what with earnestness they desired), that one might think they wrought by design, and had a distinct view of an end; for the effecting of which, they used discourse to choose the likeliest means.

To this purpose the subtilties of the Fox are of most note. They say, he uses to lie as if he were dead; therby to make Hens * 1.337 and Ducks come boldly to him. That, in the night when his body is unseen, he will fix his eyes upon poultry; and so make them come down to him from their roost. That, to rid him∣self of the fleas that afflict him in the Summer, he will sink his body by little and little into the water, while the fleas creep up to his head (to save themselves from drowning) and from thence to a bough he holds in his mouth; and will then swim away, leaving them there. That, to cousen the Badger of his earth, he will piss in it; as knowing that the rank smell of his Urine will drive the other cleanlier beast to quit it. That, when Dogs are close upon him and catching at him, he will piss upon his Tail, and, by firking that up and down, will endeavour (you may believe) to make their eyes smart; and so retard their pursuit, that he may escape from them.

And there are particular stories, that express yet more cun∣ning than all these. As, of a Fox, that, being sore hunted, hang'd himself by the teeth among dead vermin in a Warren; till the Doggs were pass'd by him, and had lost him. Of another, that, in like distress, would take into his mouth a broom bush growing upon a sleep cliff on the side hand neer his Den (which had another way to it, easie enough of access) and, by help of that, would securely cast himself into

his hole, while the Dogs, that follow'd him hastily and were ignorant of the danger, would break their necks down the rocks.

'Tis said, that, in Thracia, the Countrey people know whe∣ther the rivers, that are frozen in the winter, will bear them or no, by marking whether the Foxes venture boldly over them, or retire, after they have lai'd their ears to the Ice, to listen whe∣ther they can hear the noise of the water running under it: from whence (you may imagine) they collect, that, if they hear the current of the stream, the Ice must needs be thin; and consequently dangerous to trust their weight to it.

And, to busie my self no longer with their subtilties, I will conclude with a famous tale of one of these crafty animals, that, having kill'd a Goose on the other side of the river, and being desirous to swim over with it, to carry it to his den; before he would attempt it (lest his prey might prove too heavy for him to swim withal, and so he might lose it) he first weigh'd the Goose with a piece of wood, and then tri'd to carry that over the river, whiles he left his Goose behind in a safe place: which when he perciev'd he was able to do with ease, he then came back again, and ventured over with his heavy bird.

They say it is the nature of the Iacatray to hide it self, and imi∣tate the voice of such beasts, as it uses to prey upon: which makes them come to him, as to one of their own fellows; and then he seises on and devours them.

The Iaccal, that has a subtile sent, hunts after beasts, and, in the chase, by his barking, guides the Lion, (whose nose is not so good) till they overtake what they hunt; which peradventure would be too strong for the Iaccall: but the Lion kills the quar∣ry, and, having first fed himself, leaves the Iaccal his share; and so between them both, by the ones dexterity and the o∣thers strength, they get meat for nourishment of them both.

Like stories are recorded of some Fishes. And every day we see the invention of Beasts to save themselvs from catching: as Hares, when they are hunted, seeks always to confound the sent; somtimes by taking hedges, otherwhiles waters; som∣times running among sheep and other beasts of stronger sent;

somtimes making doubles, and treading the same path over and over; and somtimes leaping with great jumps hither and thither, before they betake themselves to their rest, that so the continuateness of the sent may not lead doggs to their form.

Now, to penetrate into the causes of these and of such like actions; we may remember, how we shew'd in the last Chapter, * 1.338 that the beating of the heart works two things: one is, that it turns about the specieses, or little corporeities (streaming from outward objects) which remain in the memory; the other is, that it is always pressing on to some motion or other. Out of which it happens, that, when the ordinary ways of get∣ting victuals or escaping from enemies, fail a creature whose constitution is active; it lights somtimes (though peradven∣ture very seldom) upon doing something, out of which the desired effect follows (as it cannot choose but fall out now and then, though chance only govern their actions): and, when their action proves succesful, it leaves such an impres∣sion in the memory, that, whenever the like occasion occurrs, that animal will follow the same method; for the same spe∣cieses do come together from the memory into the fantasie. But, the many attempts that miscarry, and the ineffectual mo∣tions which straights do cast beasts upon, are never observ'd; nor are there any stories recorded of them: no more than, in the Temple of Neptune, were kept upon the registers the relations of those unfortunate wretches, who, making vows to that God in their distress, were nevertheless drown∣ed.

Thus peradventure, when the Fox sees his labour, in chasing the hens, to be to no purpose, and that, by his pursute of them, he drives them further out of his reach; he laies himself down to rest, with a watchful eye; and perceiving those silly animals to grow bolder and bolder, by their not seeing him stir, he continues his lying still, till some one of them comes with∣in his reach; and then, on a sudden, he springs up and catches her. Or peradventure, some poultry might have strai'd with∣in his reach whiles he was asleep, and have then wakened him with some noise they made; and so he happned to seise upon one of them, without either design or pains taking before∣hand.

By such degrees he might chance to catch one the first time: and they, being setled in his memory, together with the effect, it hap'ned that, another time when hunger pressed him and sent up to his brain like spirits to those which ascended thither, whiles he say watching the hens; these spirits brought the other from his memory into the fantasie (in such sort as we have shew'd in the last Chapter), and so drove him to the same course, till by frequent repetition, it became ordinary and fa∣miliar with him. And then, they, that look only upon the per∣formance of the artifice, are apt to infer discourse and a design of reason, out of the orderly conduct of it.

But how can we concieve the Fox hath judgment, to know when the hen is come within his leap, and accordingly offers not at her, till then; unless we resort to some other principles, than what is yet declared? The answer to this objection I think will not be hard to find: for if the motion, which the presence of the object makes in the heart, be proportion'd out by nature (as there is no doubt but it is), it will not be so great and powerful, as to make the Fox leap at it, till it be arrived so near him, that he, by his nimbleness, can reach it; and so without any aim, further than by the meer flux of his passion conveniently rais'd, he doth the feat. But, if his passion be too violent, it makes him miss his aim: as we may frequently ob∣serve both in men and beasts; and particularly, when fear presses either of them to leap over a ditch, which being too broad, he lights in the midst of it.

The same watchfulness and desire to have the poulen, which then sit upon a tree out of his reach, makes him fix his eyes on them, when they are at roost; and at length, either the bright∣ness and sparkilng of them dazles the birds, and makes them come down to him, (as flies do in the night about the flame of a candle, or as fishes do to a light in a boats head), or else they are afraid; and their fear increasing, their spirits return to the heart, which therby is oppressed, and their outward parts are bereav'd of strength and motion: from whence it follows necessarily, that their footing looses their hold fast, and they tumble down half dead with fear; which happens also fre∣quently to cats, when they look wishly upon little birds that sit quietly. Or peradventure, their fear makes them giddy:

as when some man, looking down a precipice from a danger∣ous standing, falls, by the turning of his brain, though no∣thing be behind him to thrust him forwards. Or it may be, some steam comes from the Fox, which draws such creatures to him: as 'tis reported that a great and very poisonous Toad will do a Weasel, who will run about the Toad a great while, and still make his circle lesser and lesser, till at length he pe∣••ishes in the center, were his foe sits still, and draws him to him. Which he doth in such sort, as animated Mercury will draw leaf-gold duly prepared, or as the Load stone attracts Iron: and yet 'tis apparent, the Weasel comes not with his good will, but that there are some powerful chains, steaming from the body of the Toad, which pluck him thither against his liking; for, by his motions and runing, he will express the greatest fear that can be.

The method which Foxes practise to rid themselvs of their * 1.339 fleas (if it be true) is obvious enough for them to fall upon: for in Summer, their sleas, together with their thick fur'd coat, cannot choose but cause an exceeding great itching and heat in their bodies; which will readily invite them to go into the water to cool themselves. As the Merchants, at the Isles of Zante and of Cephalonia, told me (when I was there), it was the custom of our English Dogs (who were habituated to a colder clime) to run into the Sea in the heat of Summer, and lie there most part of the day, with only their noses out of the water, that they might draw breath; and would sleep there with their heads laid upon some stone; which raised them up, whiles their bodies were cover'd with the Sea: and those Dogs which did not thus, would, in one Summer usually, be kill'd with heat and Fleas.

Now, when the Fox feels the ease that the coolness of the water affords that part of him which sits in it, he goes further and further; yet would not put himself to swim (which is a labour, and would heat him, and therfore he avoids it): so that whiles he thus cools himself in some shady place (for, 'tis natural to him, in such an occasion, to resort to the cool shade, rather than to Ile in the Son) and in such there being for the most part some boughs hanging over the water; it happens naturally enough, that he takes

some of the lowest in his mouth, to support him and save hi m the labour of swiming, whiles he lies at his ease, soaking and cooling himself in the River. By which means it comes to pass, that the Fleas, finding no part of him free from water, creep up the bough to rescue themselvs from drowning: and so, when he is cool'd enough, he goes away and leaves them there. In all which finding a benefit and satisfaction, whenever the like occasion brings those species from his memo∣ry into his fantasy, he betakes himself to the same course; and therin finding his remedy, at length it grows familiar to him.

In like manner, Thales his Mule, that was heavily loaden with Salt, hap'ning to stumble and fall in a River, she was go∣ing over, the Salt melted by the water soaking into the sacks, and so she was eased of her burthen: which success made her, that whenever she came to a River, and was troubled with her loading, she would lie down in the water; and could not be reclaim'd from it, till they charged sacks of wooll upon her back, which, growing heavier by their imbibing of water, wean'd her from her former crafty habit. By which 'tis appa∣rent, that it was memory, and not judgment, which made her for a while behave her self so subtilly.

For the Foxes driving the Badger from his earth, you will * 1.340 not think it needful to allow him a forecast or design in pis∣sing in it: but, as it natural for him, to rest in a place that he meets with, fit for that purpose, so it is for him to piss in it, if the list take him while he is there; which in all likelihood it will, if he stay any time there, and give a relaxation to all his parts by sleep.

And, when he pisses in his tail and shakes it in the Dogs eyes, 'tis evident that fear, not craft, causes this effect; for it avails him little, and therfore is not likely to proceed from judgment: and of the other, when 'tis violent, 'tis a natural effect in all beasts, to contract their tails between their legs, and to make their urine come from them, (by compressing the spirits in their heart, which should support their outward parts, and strengthen their splincter muscle); which then being snap'd at and seis'd on by the Dogs shakes from their bushy tails (fit to retain it), and then, lighting in the Dogs eyes

the acrimony of it hurts them, and makes them shut their lids.

The story (if it be true) of the Fox, that, to save himself from the Dogs he heard following him in full cry, hung by his teeth among dead vermine in a warren, is a very strange one, I confess. But 'tis conceivable, how fear and weariness might cause him to seek a shelter to hide himself; and, in so plain a tract of ground, as warrens use to be, without any bush or hill to have recourse to for relief, there appearing nothing but a gallows hanging full of vermine, his fantasy might be moved (he being able to run no further) to thrust himself among those dead bodies, that he saw rest quietly: and, having no way to mingle himself with them but hanging by his teeth, he might continue in that posture, till the Dogs, not suspecting him in the air, might run under him and overshoot the sent; which whiles they cast about to recover, by runing to beat the next wood or shelter in view (as is their custom in losses of their chace, to which they are brought by their masters hunting them in that method at the first) the wily animal steals another way, and recovers himself.

This over-runing of the sent by Dogs, in the earnestness of their chace puts me in mind of Montagues Argument, out * 1.341 which he will infer, that Dogs use discourse and make syllogisms in their hunting: for (saies he) when they have fol∣low'd their chase down a Lane, that, at length, divides it self into three others, they will carefully smell at the first and second, and, not finding that it has gone in either of those, they boldly run upon the third, without ever laying their Noses to the ground; as being assured by their dis∣course and reason, that, since it went not in the two first, and there being but one remaining, it must of necessity have gone there.

But this needs no other cause, than that their eagerness of hunting having made them overshoot the sent, (which for a while remains in their noses; after they are parted from the object that caus'd it), they cast back again (as they are accustom'd to be made to do, in like occasions, by the hunters that train them up), and with their noses try the ground all the way they go; till, coming near where the chace went indeed, the

sent strikes their Noses (that by this time are grown empty of it) before they come at the place: and then they run amain in pursuit of it, with their heads held up, (which is their con∣venientest posture for runing), and all the way the sent fills them at that distance, without their needing to smell upon the Earth, to fetch it from thence.

That Fox, which used to cast himself by the advantage of * 1.342 a bough into his Den, was so closely pursued by the Dogs, the first time he ventured upon this fear, that he had not time to go into his Earth (his ordinary retreat, when he is near it) by the easy and accessible way: but, on one side, to get thi∣ther being strong in his fantasy, and on the other side, the pre∣cipice, which he had often seen, coming likewise thither from his memory; these two concurring could not choose, but make him go warily thither. And in so dangerous a leap, 'tis natural for him to help himself by any thing in the way that can advantage him; which hapning to be by catching in his mouth a bough that hung over his Den, (the only suddain means he had to take hold of any thing), and from thence taking, as it were, a new rise for a second leap, he finds him∣self in security: whiles the Dogs, unacquainted with the place, run violently on, as in the rest of their chase, and so are upon the brim of the precipice, before they per∣ceive it; and then it is too late for them to stop their course, and consequently they break their necks. Which mischief to them the Fox needs not have in his design, and accordingly tolle them that way; but, chance begeting this deliverance of him at the first when he was so hard pressed, his memory teaches him to follow the same course, whenever the lik occa∣sion occurrs.

But, how many Foxes perish in attempts, which, if they succeeded, would have been accounted by slight iudgers to be notable subtilties; but miscarrving, are esteem'd tumultuary motions without defign, caus'd by that animals fantasy and spirits, when he is in extremity? I remember how, upon a time when I was hunting one, he, being hard set, and but a little before the Dogs and Hunters, caught in his mouth the bough of a crooked Ash-tree, and run up a pretty way: which being in a hedge, he therby hung down along the side of

the hedge, and when we struck him over the ribs with our poles, he would not quit his hold, (so strongly the fear of the dogs wrought in his fantasy), till greater blows knock'd him on the head. Which shews evidently, that this action was the effect of chance pressing his fantasy to do somthing; and not any reason or discourse providing for his safety: as we have already said, upon occasion of the other hanging among the dead vermin in the Warren.

Those in Thracia that will not go over a frozen River, when the yce is too thin to bear them, are by their memory, not by their judgment taught to retire; for at other times they have been wetted, when they have heard the noise of the stream runing under the yce: or, the very runing of the water calls the specieses of swimming out from their memory along with it into their fantasy (neither of which is pleasant to them in the winter); and so disliking the noise, for the other effects sake that used to accompany it, they avoid that which begets it, and so retire from the river. And the reason of their list∣ning to the noise proceeds from the spirits, that their passion, upon apprehension of a danger, presses into the nervs of their senses, as well as into the other nervs of their brains: which accordingly makes them so vigilant, and attentive then to outward objects and motions.

That the Jaccatray or Hyaena, when he is hungry, should * 1.343 have his fantasy call out from his memory the Images of those Beasts which use to serve him in that occasion, is the ordinary course of nature; and that, together with those Images, there should likewise come along the actions and sounds which used to accompany them, and are lodged together with them in the memory, is also natural: then, as little strange it is, that by his own voice he should imitate those sounds which at that time so powerfully possess his imagination. And, having a great docility in those Organs which form the voice, like a Parrat, he represents them so lively, that the deceived beasts flock to him, and so are caught by him: which at first hap∣pens by chance; but afterwards by memory, and grows fa∣miliar to him. * 1.344

Nor can we imagine, that the Jaccal hath a design of ser∣vihg the Lion; but his nature being (like a Dog) to bark when

he feels the sent hot (which he pursues for his own sake), the Lion, that dwells in the same woods with him, meets with the noise and follows it; and peradventure would kill the Jac∣cal himself, as well as what he hunts, if he could overtake him: but he, being too nimble for the Lion, keeps out of his reach; till, having wearied the beast he chases, the Lion, that follows by the cry, comes in when he is at a bay, and soon tears in pieces what the other had not strength enough so suddainly to master, and feeds himself upon the Quarry, till he be full. All this while the 〈◊〉〈◊〉 dares not come near the Lion, but stands at a distance with fear, waiting till he have done, and then, after he is gone away, he takes his turn to feed upon what his surly Master hath left.

The like reason, 'tis probable, we might find out, among those Fishes that serve one another; if we had the conveniency of * 1.345 observing particularly how they behave themselvs: as when the Whale hath service from his little guide (if the report be true; which is a necessary circumstance to be inserted in every such tale), and others of the like strain.

The subtilty of the Torpedo (who hides himself in the mud to benum Fishes, that may afterwards serve him to feed upon) will not require to have its origin from reason, and be done by design: when you shall consider it is natural for such cold Creatures to immud themselvs, and then the Fishes that swim within the reach of his benuming faculty will be stai'd and fro∣zen there (which, because they see him not, they apprehend not, till it be too late for them to avoid it); and then, when the Tor∣pedo comes out, he feeds upon what he finds lying ready in his way.

And in like manner, the Scuttle-fish, when he is in straights of being taken by the Fishermen, casts out a blackness that is within him; and so, making the water become like Ink, he oftentimes escapes their hands in the darkned Element: which arises from no discourse of his; but fear makes him void this * 1.346 liquor that is in him (as it made the Fox void his Urine), and in consequence ther' to the effect follows.

Lastly, when Hares use those means we have mention'd, to confound the sent and save themselvs from the Dogs

that hunt them; we may observe, that they take therin the readiest ways, and the most obvious to sense, to avoid the evil they flie from. For, what can be more direct to that effect, than to hide themselvs in Hedg-bottoms, or in Woods? Or to swim over a River, when that is the most immediate way to run from the Dogs? And when they are in a plain, where there is no other shelter but flocks of Sheep or herds of Deer, what can be more natural, than for them to hide themselvs among them, and run along with them; till the cry of the approach∣ing Hounds fright them away, whiles those tamer beasts abide it neerer?

Their doublings backward and forward may proceed from their fear, that diverts them still from the way they are in at present; till the Dogs coming near put them out of those wavering, and makes them run straight away: for they ne∣ver double, but when they are a great way before the dogs, and do not hear them. Or else it may be, that, not hearing or see∣ing the dogs, their fear may be almost passed; and then the agitation which their spirits are in, governs the motions of their body, and will not let them rest, till they be more appeased, (as you may see weary people, that at their first ceasing from running, cannot sit still: the like of which happens al∣so frequently in the motions of joy or of anger), and so it makes them walk backwards and forwards, in a pace proportionate to the agitation of the spirits within: and somtimes those moved spirits make them bound and leap to and fro (like the L••af with Quicksilver, we have heretofore spoken of) as they issue from the heart by pulses and strokes; which hap∣pens when they begin to settle towards rest. Or else perad∣venture their form is so framed, that, if they should get into it otherwise, than by a jump, they would disorder some part of it; and so be unfenced and a cold, or otherwise at uneasie, du∣ring their repose: and therfore their jumping to and fro, be∣fore they leap plumb in, is to take their aim (not much un∣like to Dogs, turning about several times before they lie down); for Hare-finders (who use to watch them, say they will do thus, though they be not pursued. And thus these actions which are imputed to craft, therby to confound the Dogs, or to wisdom, to walk themselvs till they be grown into a

fitting temper to sit still; may all of them be reduced to those material and corporeal causes, which make them to do their o∣ther ordinary motions, wherin we find no difficulty.

If that of the Foxes weighing his Goose, before he would * 1.347 venture to carry it over the River, were plainly true, as it is set down; I avow, I should be hard set, to find the principles from whence that discretion in him proceeded: but I conceive his tale may be pa••ed with that, which tells us of another Fox, who, having his prey taken from him by an Eagle, brought the next day a new prize into the same place, having first rolled it in the fire, so that some burning coals stuck upon it; which the Eagle coming again and snatching from him, carried to her Nest, which was therby set on fire, and the young ones, falling down, became the Foxes share, instead of what their Dam had rob'd him of. Such stories, so quaintly contrived, are fitter for a moral, than for a natural Philosopher. Aesope may entertain himself and his Disciples with them; whiles all the reflection I shall make upon them, is, that when I hear any such finely order'd Tales, I cannot doubt but they are well amended in the relation, by those that tell them: it being the inclination and custom of most men, (partly through a desire of having strange things come from them, and partly out of a care that what they say may appear like truth, and so be the easier believ'd) to add circumstances beyond the truth of the matter; which increasing at every new mans relation of the same accident (for this humour reigns very generally), at length, so handsom and yet so strange a Tale is com∣posed, that the first Author or Teller of it, wonders at it as well as others, and cannot discern that his story begot this lat∣ter.

Therfore, when one of these fine tales is proposed to specu∣late on, and that I have no light to guide me in determining what part of them to allow, and what to reject; I think it bet∣ter to expect an authentick record of it, than to be too hasty at guesses: leaving such as pretend ability in reading of Riddles, to descant of the ways how such actions may be effected. But for others, that have a semblance of truth or happen ordina∣rily, be they at the first sight never so like the operations of rea∣son, I doubt not, but the causes of them may be reduced to

the principles we have already established; and the waies of per∣forming them may be pitched upon by such discourses about them, as we have made about those examples we have above produced. Especially, if the actions themselves were observ'd by one that could judg of them, and were reported with a desire of expressing the truth nakedly as in it self it lieth: for, divers times it happens that men, saying nothing but truth, express it in such a manner and with such terms, that the ignorant hearer conceives the thing quite another way, than indeed it is, meerly for the too emphatical expressions; especially, if the relator himself misses in conceiving the true causes of what he reports, and so expresses it proportionably to those which he apprehends.

To conclude then this first branch; we see how the Doubting, the Resolving, the Aiming, the Inventing, and the like, which we experience in Beasts, may, by the vestigia's we have traced out, be follow'd to their root, as far as the division of Rarity and Density: without needing repair to any higher principle, but the wisdom of the Orderer and Architect of Nature, in so admirably disposing and mingling these material, gross, and liveless bodies, that strange effects, and incomprehensible to them who will not look into their several joints, may follow out of them, for the good of the creature in whose behalf they are so order'd.

But, before we go to the next point, we cannot for bear men∣tioning * 1.348 their vanity, as well as ignorance, who to purchase the estimation of deeper knowers of Nature would have it believ'd, that Beasts have compleat Languages, as Men have, to discourse with one another 〈◊〉〈◊〉; which they van••d they had the intelligence of. ••Tis 〈◊〉〈◊〉▪ that, 〈◊〉〈◊〉 us, speaking or talking is an operation of reason; not because it flows immediately from reason, but be∣cause by the command and direction of reason 'tis form'd, and is no where to be found without reason: which those irrational Philosophers which pretended to understand the Language of Beasts, allow'd them, as well as the ability of talking to one ano∣ther; but it was because they had more pride than knowledg. Of which rank one of the chief was Apollonius, sirnamed from Th••∣na: for, if he had known how to look into the nature of beasts, he would have perceiv'd the reason of the divers voices, which the same beast in divers occasions forms.

This is evident, that an Animals lungs and chest, lying so neer as they do, to his heart; and all voice being made by the breath's coming out of his mouth and through his windpipe: it must necessarily follow, that, by the divers ordering of these instruments, his voice will become divers; and these instru∣ments will be diversly order, in him, according to the divers motions of his heart, that is, by divers passions in him, (for so we may observe in our selvs, that our breath is much changed by our being in passion). And consequently, as a beast is agitated by various passions, he must needs utter variety of voices; which cannot choose but make divers impressions in other beasts, that have commerce with him, whether they be of the same kind as he is, or of a different. And so we see, that, if a Dogg, setts upon a Hog, and the bitten hogs cry makes an impression in the other Hogs, to come to their fellows rescue; and in other Dogs to run after the crying Hog: in like manner, anger in a Dog makes snarling or barking, pain, whining, desire, another kind of barking; and his joy of seeing a person that he uses to receive good by, will break out in another kind of whining. So in a Hen, her divers passions work divers kinds of clocking; as, when she sees a Kite, she hath one voice, when she meets with meat another, when she desires to gather her Chickens un∣der her wings, a third: and so, upon divers occasions, a divers sound; according to the divers ordering of her vocal instru∣struments, by the passion which presses her heart: So that, who would look curiously into the motions of the variously disposed vocal instruments of Beasts, and into those of the spirits about a Beasts heart (which motion, we have shew'd, is passion) would be able to give account, why every voice of that beast was such a one, and what motion about the heart it were that caus'd it.

And as much may be observ'd in Men, who, in pains, and griefs; and other passions, use to break out into those voices, which we call Interjections; and which signifie nothing in the Understanding of them that form them, but to the Hearer are signs of the passion from whence they proceed: which if a man heedfully mark in himself, he will perceive, that they are nothing else, but the sudden eruptions of a great deal of breath together; caus'd by some compression made within him, by the

pain he is in. Which is the reason, that the striving against groaning, in certain occasions, doth fick persons much harm: for, it disorders the natural motions of some principal parts within them, that are already too much agitated; and the counter motion, by which they are check'd, puts them fur∣ther into a more violent agitation. In the observation of these natural cruptions of mens breath, caus'd by passion, our Fore∣fathers of old were so industrious; as to transfer the imita∣tion of nature in this particular into Mufick: so that their kinds of Musick were distinguish'd, according to the division of mens passions; and, by similitude, would raise them in the hearers.

Out of this discourse also a reason may be given, why Birds are more musical, than other creatures; to wit, because they are of a hotter complexion, and therfore, to their bigness require more breath and air to cool them; and consequently make more noise, and more variety of it. Likewise, among Beasts, Doggs are the most vocal of any that converse with us; who, by their ready anger, appear to be the hottest. Among Men, those that are merry, or soon become heated with a little wine, are given to talking or singing: and so are children, and women likewise; not so much through abundance of heat, as because their heat doth easily vent.

And thus 'tis evident, that there is no true Language among Beasts: their voices not being tokens of divers things or concep∣tions, but meerly the effects of divers breathings, caus'd by di∣vers passions. Wherfore, since both breathing and passion are easily reduced to the common principles of Rarity and Density; we need not trouble our selvs any further, to seek into the ori∣gine of this vocal faculty of Beast.

CHAP. XXXVII. Of the Docility of some irrational animals: and ••f certain continuate actions of a long tract of time, so orderly perfarm'dly them, that they seem to argue knowledge in them.

AS for Docility, (which is our second head), Apes and Elephants are most famed. Though peradventure, the * 1.349 cunning and obedience of our Hawks and Dogs is no whit inferiour to what is reported of them; and would be as much admired, were it not so common. I have, by sundry persons who have seen him, been told of a Baboon, that would play certain Lessons upon a Gittar. The Indian Histories make mention of Apes, that will go to the Tavern and fetch Wine for their Masters; as Lipsius's Dog would bring his Master, as much meat from the Market, as he carried money to his But∣cher to pay for. Of Elephants likewise strange things are told. But, because we cannot easily judg how to understand reports, wherof we have not seen the experience, nor how far to be∣lieve them; I intend not to insist upon the examining of them; for, by looking into the nature and aut of our Hounds that fol∣low a sent of bloud, or that draw dry foot; and of our Hawks, especially of the decoy-Ducks and Cormorants; a guess may be given at all the rest. And although these things, told at ran∣dom, may justly seem very admirable to any man, the first time he hears of them; yet, to him that understands how they are taught, there is no one passage but will appear plain e∣nough.

The first degree is, to tame the Hawk, by watching her from sleep; and to acquaint her with the man, by continually carry∣ing her upon his fist, and using her to take her meat quietly, as she sits upon his hand. Then he makes her hop a little way to it in a pair of cranes, and, after a while, kill a seeled pigeon; from which he takes her, when she is grown steady in her lesson so far, and feeds her up with other meat: and thus, in time, he brings her to his flie at what he will have her, and to be content

with a small reward; leaving her quarry to her Master: So that a spectator, who understands not the Mystery nor ever saw Hawking before, may well admire to see a Bird so dutifully and exactly obey a mans command; and may conceive she has a reasonable soul, wherby to understand him and dis∣course of the means to bring his purpose to effect: wheras in∣deed, all this is no more, than to make her do, for you, and when you please, the same which she doth by nature to seed her self.

The cunning of Dogs is begotten the same way. Coy-ducks are beaten and whip'd to what they are taught; like setting∣dogs. Cormorants have their throats tied, that they may not swallow the fish, they catch; but be constrain'd to bring it to the man that imploys them. So that, looking along step by step, you shall meet with nothing but what is plain and easie to be taught, and performed by sense and memory; with∣out needing to attribute any discourse or reasoning to beasts.

Apes are likewise taught, as dogs may be, to carry things to a certain house; where, receiving what is given them, they re∣turn home with it: and you may be confident, this serviceable∣ness of the Ape grew out of his being carried first to the Ta∣vern by the maid or boy, who there gave him somwhat that pleas'd him; and then being made to carry the pot along by the boy; and afterwards money in one hand, and the pot in the o∣ther, wherof some drawer discharg'd him, taking the one, and filling the other, and withall giving him a reward, which also was repeated to him, at his return home with his full pot: till at last, when he was sufficiently used to this exercise, he would of himself, go straight thither, as soon as he was harnessed so, as he he used to be for this service. Which appears to be assue∣faction and custome, not judgment; by his receiving indiffer∣ently whatever is put into his pot.

And, by the Tale of Lipsius's dog; from whom other less dogs snatching, as he troted along, part of what hung out of his Basket (which he carried in his mouth), he set it down to worry one of them: whiles, in the mean time, the others fed at liberty on the meat that lay there unguarded; till he, com∣ing back to it, drove them away, and himself made an end

of eating it up. Wherby we may concieve, that the species of carrying his basket to his Master (which custome had setled in his memory) was disorder'd and thrust out of his fantasie, by a stronger, of fighting, for his meat with the other currs: after which it follow'd naturally in his fantasie, to eat what he had fought for. And that sending then spirits into his nervs, agree∣able to the nature of it, and governing the parts depending of the brain; a motion and action ensued, which was sutable to the object in the fantasie; and this could be none other, but of eating what the fantasie found conformable to its na∣ture.

The Baboon, we have mention'd, might be taught some * 1.350 lessons made on purpose with very few stops, and upon an in∣strument wheron all the strings may be strucken with one blow, and but one fret to be used at a time, and that fret to be stopp'd with one finger: of which much labour and time might beget a habit in him; and then, imitation of the sound might make him play in due measure. And, if we will mark it in our selvs, we shall see that, although, in the first learning of a lesson on the Lute, we imploy our reason and discourse about it; yet, when we have it very perfect, our fingers (guided by a slight fantasie) fall by custome, without any reflection at all, to play it as well, as if we thought never so carefully upon it. And there is no comparison, between the difficulty of a Gittar and of a Lute.

I have been told, that at the Duke of Florence's marriage, there was a dance of Horses, in which they kept exact time of Musick. The means used for bringing them to it, is said to have been, by tying and hampering their legs in such a sort, that they could lift them up, but in a determinate way: and then set∣ing them upon a pavement, that was heated underneath so hot that they could not endure to stand still; whiles such Musical Airs were plaid to them, as fitted their motions. All which being often repeated, the Horses took a habit, that, in hearing those Airs, they would lift up their legs in that fashion; and so * 1.351 danced to the tune they had been taught.

Of the Elephants, 'tis said that they may be taught to write; and that, purely upon words and commanding them, they'l do what they are bidden; and that they are able to keep ac∣count;

and will leave working at a precise number of revolu∣tions of the same action, which measures out their task to them. All which (as I said before), if it were plainly and literally true, would require a very great consideration: but because the teachers of Beasts have certain secrets in their art, which standers by, do not reach to, we are not able (upon such scan∣ty relations, as we have of them) to make sufficient judgment how such things are done; unless we had the managing of those creatures, wherby to try them in several occasions, and observe what cause produces every operation they do, and by what steps they attain to their instructions and serviceable∣ness.

'Tis true, the uncontrolled reports of them oblige us to be∣lieve some extraordinary matter of their docility, and of strange things done by them: but with all, the example of other taught∣beasts among us, and of the strange judgments that are made of them, by persons who do not penetrate into their causes, may instruct us how easily it is to mistake the matter; and assure us, that the relations made us do not always punctually a∣gree with the truth of what passed. He that should tell an Indian what feats Banks's Horse would do; how he would re∣store a glove to the due owner, after his Master had whisper'd that mans name in his ear; how he would tell the just number of pence in any piece of silver coyn, barely shew'd him by his Master; and even obey presently his command, in discharging himself of his excrements, when ever he bad him (so great a power art may have over nature:) would make him, I believe, admire more at this learned beast, than we do at their docile E∣lephants, upon the relations we have of them. Wheras, every one of us knows, by what means his painful Tutor brought him to do all his tricks; and they are no whit more extxaordinary, than a Fawkners manning of a Hawk, and training her to kill Partridges, and to flie at the retrive: but do all of them (both these, and all other jugling artifices of beasts) depend upon the same or like principles; and are known to be but directions of nature, order'd by one that composes and levels her opera∣tions to another end further of off (in those actions) than she of her self would aim at. The particulars of which, we need not trouble our selvs to meddle with.

But, 'tis time we come to the third sort of actions per∣form'd by beasts, which we promised to discourse of. These seem * 1.352 to be more admirable, than any we have yet touched; and are chiefly concerning the breeding of their young ones. Above all others, the orderly course of Birds, in this affair, is most re∣markable. After they have coupled, they make their nest, they line it with 〈◊〉〈◊〉, s••w and fathers; they lay their eggs, they 〈◊〉〈◊〉 upon them, they 〈◊〉〈◊〉 them, they feed their young one, and they teach them to she: all which they do with so continuate and regular a method, as no man can direct or imagine a better.

But, as for the regularity, orderliness, and continuance of these actions, the matter is easie enough to be conceiv'd. For, seeing the operation of the male makes a change in the female; and this change beginning from the very first, grows by time into divers proportions: 'tis no wonder that it breeds divers dispo∣sitions in the female; which cause her to do different actions, correspondent to those divers dispositions. Now, those acti∣ons must of necessity be constant and orderly, because the cau∣ses, whence they proceed, are such.

But, to determine in particular, how it comes to pass, that every change in the female disposes her to such and such acti∣ons, there is the difficulty; and it is no small one: as well for that there are no careful and due observations made, of the effects and circumstances which should guide us to judg of their causes; as because these actions are the most refined ones of Sensitive creatures, and flow from the top and perfecti∣on of their nature, and are the last strain of their utmost vi∣gour, to which all others are subordinate. As, in our enquiry into the motions and operations of the bodies of a lower Orb, than these, we meet with some (namely, the Loadstone, and such like) of which it is very hard to give exact and plain account; the Author of them reserving something from our clear and distinct knowledge, and suffering us to look upon them but through a mist: in like manner we cannot but expect, that, in the depth of this other perfecter nature, there must be somwhat wherof we can have but a glimering and imperfect notion. But as in the other, it serv'd our turn, to trace out a way how these operations might be effected by bodies, and by local

motion (though peradventure, we did not in every circum∣stance hit exactly upon the right); therby to defend our selvs from admiting those chymerical Qualities, which we had already condemned upon all other occasions: so, I conceive, it will be sufficient for us in this, to shew how these actions may be done by the senses, by the motion of corporeal spirits, and by material impressions upon them; without being con∣strain'd to resort to an immaterial principle, which must fur∣nish birds with reason and discourse. In which, it is not ne∣cessary for my purpose, to determine precisely every step by which these actions are performed, and to settle the rigorous truth of them: but, leaving that to those who shall take pains to deliver the history of their nature, I will content my self with the possibility and probability of my conjectures. The first of which qualities I am obliged to make plain; but the latter concerns this Treatise no more, than it would do a man to enquire anxiously into the particulars of what it is that a beast is doing, whiles, looking upon it at a great distance, he perceivs plainly that it moves it self: and his errant is, but to be assured whether it be alive or dead; which the moving of it self in com∣mon sufficiently demonstrates, without descending into a par∣ticular search of what his motions are.

But let us come to the matter. First, I conceive no man will make any difficulty in allowing, that it is the temper of the blood and spirits in Birds (brought therto by the quality of their food, and the season of the year), which makes them couple with one another; and not any aim or desire of having young ones, that occasions this action in them. Then it follows, that the Hens eggs will encrease in her belly; and, when they grow big, they cannot choose but be troublesome unto her: and therfore, must of necessity breed in her an inclination to rest in some soft place, and to be rid of them. And, as we see a Dog or a Cat, press'd by nature, searches about to find a convenient place to disburthen themselvs in, not only of their young ones, but even of their excrements; so do Birds: whose eggs within them making them heavy and unfit to flie, they begin to sit much and are pleas'd in a soft and warm place; and thereupon are delighted with straws and mosse and other gentle sub∣stances,

and so carry them to their sitting place. Which that they do not by design is evident by the manner of it: for, when they have met with a straw or other fit material, they flie not with it directly to their nest, but first to a bough of some tree, or to the top of a house; and there they hop and dance a while with it in their beaks, and from thence skip to another place, where they entertain themselvs in like manner, and at last, they get to their nest. Where, if the straws should lie confusedly, their ends would prick and hurt them; and therfore they turn and alter their positions till they lie smooth: which we that look upon the effect, and compare them with our performing of like actions (if we had occasion), may call a judicious order∣ing of them; wheras in them, it is nothing but removing such things as press upon their sense, till they cause them no more pain or unquierness.

Their plaistering of their nests may be attributed to the great heat reigning in them at that time; which makes them still be dabling in moist clay, and water, and gravel, (without which, all birds will soon grow sick, blind, and at length die): which (for the coolness of it) they bring home to their nests, in their beaks and upon their feet; and, when it grows dry and con∣sequently troublesome to them, they wipe it off, and rub their dirty parts upon the place where they use to sit, and then flie for more to refresh themselvs with.

Out of all which actions (set on foot by the wise orderer of nature, to compass a remote end, quite different from the im∣mediate end that every one of them is done for) there results a fit and convenient place for these little builders (that know not what they do, whiles they build themselvs houses) to lie and lay their eggs in: which the next year, when the like occa∣sion occurrs, they build again; peradventure then, as much through memory of the former, as upon their temper and other circumstances, moving their fantasy, so as we have set down.

In like manner, that, whiles the Halcyon layes and hatches her eggs, the Sea is calm, needs no more be attributed to the wisdom and providence of that bird, in choosing a fit season, than to any good nature or discourse in that rouling and merci∣less

Element; as though it had a pious care of preserving the eggs committed to his trust: no such supplements are requisite to be added to the distributions of nature; who hath set mate∣rial causes on foot to produce a conjuncture of both those ef∣fects, at the same period of time, for the propagation of this animal's species.

In fine, both the time and place of the Halcyon's breeding, and the manner and order and season of all birds making their nests, proceeds from secret motions: which require great observing and attention to understand them; and serve for directions to every bird, according to her kind, to make her nest fittest for her use. Which secret motions, we cannot doubt but are material ones, and a••se out of the constitution and temper of their bodies and spirits; which, in like circumstan∣ces, are alike in them all: for all the birds of one kind make their nests exactly alike. Which they would not do, if this work proceeded from reason in them, and were govern'd by their own election and design: as we see it happen among men upon all occasions, either of building houses, or of making clothes, or of what action soever is guided by their reason governing their fantasy; in all which we see so great variety and inconstancy.

Therfore, this invariability in the birds operations must proceed from a higher intellect, that hath determinately and precisely ordered a complex or assembly of sundry causes, to meet infallibly and by necessity, for the production of an effect he hath designed: and so, the birds are but material instru∣ments to perform, without their knowledg or reflexion, a su∣periour reason's counsels; even as in a clock, that is composed of several pieces and wheels, all the parts conspire to give no∣tice of the several effluxes and periods of time, which the maker hath order'd it for.

And, though this be a work of reason and discourse in him that set it together; yet the instrumental performance of it depends meerly of local motion, and the revolutions of bodies, so orderly proportion'd to one another that their effects cannot fail, when once the engine is wound up. In like manner then, the Bird is the engine of the Artificer, infinitely more perfect and knowing and dexterous than a poor clock∣maker:

and the plummets which make it go, are the row and order of causes chain'd together; which, by the design of the supream workman, bring to pass such effects as we see in the building of their nests, and in doing such other actions, as may be compared to the strikings of the clock, and the ringing of the alarm at due times.

And as that King of Claina, upon his first seeing a Watch, thought it a living and judicious creature, because it moved so regularly of it self; and believ'd it to be dead, when it was run out: till the opening and winding it up discover'd to him the artifice of it. So any man may be excused, that looking upon these strange actions and this admirable oeconomy of some li∣ving creatures, should believe them endew'd with reason; till he have well reflected upon every particular circumstance of their nature and operations: for then he will discern how these are but material instruments of a rational agent, working by them; from whose orderly prescriptions they have not power to swerve in the least circumstance that is. Every one of which, consider'd singly by it self, hath a face of no more diffrently, than that (for example) an Engineer should so order his matters, that a Mine should be ready to play exactly at such an hour; by leaving such a proportion of kindled match hanging our of one of the barrels of powder, whiles, in the mean time, he either sleeps or attends to somthing else.

And, when you have once gain'd thus much of your self, to agree to an orderly course and generation of any single effect, by the power of a material cause working in it; raise but your discourse a strain higher, and look with reverence and duty up∣the Immensity of That Provident Architect, out of whose hands these master-pieces issue, and to whom it is as easy to make a chain of causes, of a thousand or million of links, as to make one link alone: and then you will no longer stick at allowing the whole oeconomy of those actions, to be nothing else but a production of material effects, by a due ranging and ordering of material causes.

But, let us return to our theam. As we see that milk com∣ing into the breasts of live-bearing female creatures, when they grow very big, heats and makes them seek the

mouths of their young ones, to disburthen and cool them: so, the carriage and bigness of the Eggs heats exceedingly the breasts and bodies of the Birds; and this causes them to be still rubbing of their breasts against the sides of the nests (wherto their unwieldiness then contines them very much) and with their Beaks to be still picking their Feathers, which being then apt to fall off and mew (as we see the hair of wo∣men with child is apt to shed) it happens that, by then they are ready to lay their Eggs, they have a soft bed of their own Feathers made in their Nests, over their courser mattress of straws they first brought thither. And then, the Eggs pow∣erful attracting of the annoying heat from the Hens breast (whose imbibing of the warmth, and stone-like shell, cannot choose but cool her much) invites her to sit constantly upon them; till sitting hatches them. And 'tis evident, that this sitting must proceed from their temper at that time, or from some other immediate cause which works that effect; and not from a judgment that doth it for a remote end: for, house-wives tells us, that, at such a season, their Hens will be sitting in every convenient place they come to, as though they had Eggs to hatch, when never a one is under them; so as it seems, that at such time, there is some inconvenience in their bodies, which by sitting is eased.

When the Chickens are hatched, what wonder is it, if the little cryings of tender creatures, of a like nature and language with their Dam, move those affections or passions in her bo∣some, which causes her to feed them; and so defend and breed them, till they be able to shift for themselvs? For all this there needs no discourse or reason; but only the motion of the blood about the heart (which we have determin'd to be passion) stir'd by the young ones chirpings, so as may carry them to those actions, which by nature (the supreme in∣tellect) are order'd for their preservation. Wherin the Birds (as we have already said) are but passive instruments, and know not why they do those actions: but do them they must, whenever such and such objects (which infallibly work in their due times) make such and such impressions upon their fantasies; like the allarum that necessarily strikes, when

the hand of the Dial comes to such a point, or the Gun-pow∣der, that necessarily makes a ruine and breach in the wall, when the burning of the match reaches to it.

Now, this love in the Dam, growing by little and little wearisome and troublesome to her, and not being able to sup∣ply their encreased needs, which they grow every day stronger to provide for of themselvs; the strait commerce begins to die on both sides: and by these degrees the Dam leaves her young ones to their own conduct.

And thus you see, how this long series of actions may have orderly causes, made and chain'd together, by him that knew what was fitting for the work, he went about. Of which, though 'tis likely I have missed the right ones (as it cannot choose but happen in all disquisitions, where one is the first to break the Ice, and so slenderly informed of the particular circumstan∣ces of the matter in question, as I profess to be in this); yet I concieve, this discourse plainly shews, that he, who hath done more, than we are able to comprehend and understand, may have set causes sufficient for all these effects, in a better order and in completer ranks, than those we have here expres∣sed: and yet in them, so coursely hew'd out, appears a possibi∣lity of having the work done by corporeal agents. Surely, it were very well worth the while, for some curious and judici∣ous person to observe carefully and often the several steps of nature in this progress: for I am strongly perswaded, that, by such industry, we might in time arrive to very particular knowledge of the immediate and precise causes, that work all these effects. And, I conceive, that such observation needs not be very troublesome; as not requiring any great variety of creatures to institute it upon: for, by marking carefully all that passes among our home-bred Hens. I believe it were easy to guess very nearly at all the rest.

CHAP. XXXVIII. Of Prescience of future events, Providences, the knowing of things never seen before; and such other actions, observed in some living creatures: which seem to be even above the reason that is in man himself.

THe fourth and last kind of actions, which we may with * 1.353 astonishment observ among beasts, I conceive will avail little to infer, that the creatures which do them, are endew'd with reason and understanding: for such they are, as, if we should admit that, yet we should still be as far to seek for the causes, whence they proceed. What should move a Lamb to tremble at the first sight of a Woolf? or a Hen at a Kite never before seen? neither the grimest Mastiff, nor the biggest Owl will at all affright them.

That which, in the ordinary course of nature causes beasts to be afraid of men, or of other beasts, is the hurt and evil they recive from them: which coming into their fantasie, together with the Idea of him that did it, is also lodg'd together with it in the memory; from whence they come link'd or glew'd to∣gether, when ever the stroke of any new object calls either of them back into the fantasie. This is confirm'd by the tame∣ness of the birds and beasts, which the first discoverers of Islands not inhabited by men, found in those they met with there. Their stories tell us, that, at their first arrival upon those coasts, (where it seems men had never been) the birds would not flie away, but suffer'd the Mariners to take them in their hands; nor the beasts, which with us are wild, would run from them; but, their discourteous guests used them so hardly, as they soon chang'd their confidence into distrust and aversion; and by little and little, grew by their commerce with men, and receiving injuries from them, to be as wild, as any of the like kind in our parts.

From the Dams and Sires, this apprehension and fear at

the sight of men, so deeply rooted in them, is doubtless trans∣mitted to their young ones; for it proceeds out of the dispositi∣on of the body, and the passion immediately made in the heart; and that is as truly a material motion as any whatever can be, and must have setled material instruments fitted to it, if it be constant, as well as any other natural operation whatever. And this passion of the heart proceeds again from a perpetual connexion of the two objects in the memory: which, being a perpetually constant thing, is as true a quality of that beasts brain in whom it is, as the being of a quick or dull apprehension, or apt to know one kind of meat from another (which is natural to the whole species); or any other quality whatever, residing in that beast.

Wherfore 'tis no wonder, that it passes by generation to the off-spring (which is a thing so common, even in mankind, * 1.354 as there can be no doubt of it) and is at first made by a violent cause, that greatly alters the body: and consequently the seed must be imbew'd with a like disposition; and so it pas∣ses together with the nature of the Sire, or of the Dam, into the brood. From hence proceeds, that children love the same meats and exercises, that their Fathers and Mothers were affe∣cted with; and fear the like harms.

This is the reason, why a Grand-child of my Lord of Dorset (whose honour'd name must never be mention'd by me, without a particular respect, and humble acknowledgment of the noble and steady friendship, he hath ever been pleas'd to honour me with) was always extremely sick, if but the Nurse did eat any Capers (against which my Lord's antipathy is famous) whiles she gave suck to that pretty infant. The Children of great Mathematicians, who have been used to busie their fantasies continually with figures and proportions, have been often∣times observ'd to have a natural bent to those Sciences. And we may note, that, even in particular gestures, and in little sin∣gularities in familiar conversation, children will oftentimes resemble their Parents; as well as in the lineaments of their fa∣ces. The young ones of excellent setting Dogs will have a notable aptitude to that exercise; and may be taught with

half the pains, that their sire or dam was; if they were chosen out of a race of Spaniels not trained to setting. All which effects can proceed from no other cause, but (as we have touch'd al∣ready) that the fantasy of the parent alters the temper and disposition of his body and seed, according as it self is tem∣per'd and disposed; and consequently, such a creature must be made of it, as retains the same qualities: as 'tis said, that sufficient Tartar, put at the root of a tree, will make the fruit have a winy taste.

But, nothing confirms this so much, as certain notable ac∣cidents; * 1.355 wherof though every one in particular would seem incredible, yet the number of them, and the weight of the re∣porters (who are the witnesses) cannot choose but purchase a general credit to the kind of them. These accidents are, that, out of some strong imagination of the parents, but especially of the mother in the time of conception, the children draw such main differences, as were incredible, if the testifying au∣thority were not so great: but, being true, they convince be∣yond all question the truth we have proposed, of the parents imagination working upon, and making an impression in the seed, wherof children or young ones of their kind are made. Some children of white parents are reported to havebeen black, upon occasion of a Black-moors picture too much in the mo∣thers eye. Others are said to have been born with their skins all hairy; out of the sight of St John Baptist's picture as he was in the desart, or of some other hairy image. Another child is famed to have been born disformed, so as Devils are painted; because the sather was in a Devils habit when he got the child.

There was a Lady, a kinswoman of mine, who used much to wear black patches upon her face (as was the fashion among young women); which I, to put her from, used to tell her in jest, that the next child she should go with, whiles the sollici∣tude and care of those patches was so strong in her fantasy, would come into the world with a great black spot in the midst of its forehead: and this apprehension was so lively in her imagination at the time she proved with child, that her daugh∣ter was born mark'd just as the mother had fansied; which

there are at hand witnesses enough to confirm, but non more pregnant, than the young Lady her self, upon whom the mark is yet remaining. Among other creatures, 'tis said, that a Hen hatch'd a Chicken with a Kites bill; because she was frighted with a Kite, whiles the Cock was treading her. The story of Jacol's Sheep is known to all; and some write, that the paint∣ing of beautiful colour'd pigeons in a Dove-house will make the following race become like them: and in Authors, store of such examples may be found.

To give a reasonable and fully satisfying cause of this great effect, I confess, is very difficult; since, for the most part, the parents seed is made long time before the accoupling of the male and female: and though it were not, we should be mainly to seek for a rational ground to discourse in particular, upon it. Yet, not to leav our Reader without a hint which way to drive his inquisition, we will note thus much; that Aristotle and o∣ther natural Philosophers and Physicians affirm, that, in some persons, the passion is so great in the time of their accoupling, that, for the present, it quite bereavs them of the use of rea∣son, and they are for the while in a kind of short fit of an E∣pilepsie. By which 'tis manifest, that abundance of animal spirits then part from the head, and descend into those parts which are the instruments of generation. Wherfore, if there be abundance of specieses of any one kind of object then strong in the imagination, it must of necessity be carryed down toge∣ther with the spirits into the seed: and by consequence, when the seed infected with this nature begins to separate and di∣stribute it self, to the forming of the several parts of the Em∣bryon; the spirits, which resort into the brain of the child (as to their proper Element) and from thence finish all the outward cast of its body (as we have above described) somtimes happen to fill certain places of the childs body with the infection and tincture of this object; and that according to the impression with which they were in the mothers fantasy: for so, we have said, that things which come together into the fantasy naturally stick toge∣ther in the animal spirits. The hairiness therfore will be occasioned in those parts, where the Mother fansied it to

be: the colour likewise, and such extancies or defects, as may any way proceed from such a cause, will happen to be in those parts, in which they were fansied. And this is as far, as is fit to wade into this point; for so general a discourse as ours is, and more, than was necessary for our turn; to the serving wherof, the verity of the fact only, and not the knowledg of the cause, was required: for we were to shew no more, but that the apprehensions of the parents may des∣cend to the children.

Out of this discourse, the reason appears, why beasts have an aversion from those who use to do them harm: and why this aversion descends from the old ones to their brood; though it should never have hapned that they had formerly encountred with, what, at the first sight, they fly from and a∣void.

But yet the reason appears not, why (for example) a * 1.356 Sheep in England (where there are no Wolves bred, nor have been these many ages) should be afraid and tremble at sight of a Wolf; since neither he, nor his dam or sire, nor theis, in multitudes of generations, ever saw a Wolf, or receiv'd hurt by any. In like manner, how should a tame Weasell, brought into England from Ireland (where there are no poisonous crea∣tures), be afraid of a Toad as soon as he sees one? Neither he, nor any of his race, ever had any impressions of following harm made upon their fantasies; and as little can a Lion receive hurt from a houshold Cock: therfore we must seek the reasons of these and such like Antipathies a little further; and we shall find them hanging upon the same string, with Sympathies pro∣portionable to them.

Let us go by degrees: We daily see, that Dogs will have an aversion from Glovers, that make their ware of Dogs skins: they will bark at, and be churlish to them, and not en∣dure to come near them; though they never saw them be∣fore. The like hatred they will express to the Dog-killers in the time of the Plague, and to those that flea Dogs. I have known of a man that used to be imploid in such affairs, who, passing, somtimes over the grounds near my Mothers house (for he dwellt at a Village not far off), the Dogs

would wind him at a very great distance, and all run furiously out the way he was, and fiercely fall upon him; which made him go always well provided for them: and yet he has been somtimes hard put to it, by the fierce Mastiffs there, had it not been for some of the Servants coming in to his rescue; who, by the frequent hapning of such accidents, were warned to look out when they observ'd so great commotion and fury in the dogs, and yet perceiv'd no present cause for it. War∣reners observe, that vermin will hardly come into a trap wher∣in another of their kind hath been lately kill'd: and the like happens in Mouse-traps, into which no Mouse will come to take the bait, if a Mouse or two have already been kill'd in't; unless it be made very clean, so that no scent of them remain upon the Trap, which can hardly be done on the sudden, other∣wise than by fire.

'Tis evident, that these effects are to be refer'd to an activi∣ty of the object upon the sense: for, some smell of the skins, or of the dead dogs, or of the vermine, or of the Mice, can∣not choose but remain upon the Men and Traps; which, being alter'd from their due nature and temper, must needs offend them. Their conformity, on the one side, (for somthing of the canine nature remains) makes them have easy ingres∣sion into them; and so they presently make a deep impres∣sion: but, on the other side, their distemper from what they should be makes the impression repugnant to their nature, and be disliked by them; and to affect them worse, than if they were of other creatures, that had no conformity with them. As we may observe, that stinks offend us more, when they are ac∣companied with some weak perfume, than if they set upon us single; for the perfume gets the stink easier admittance into our sense: and in like manner, 'tis said that poisons are more dangerous, when they are mingled with a cordial that is not able to resist them; for it serves to convey them to the heart, though it be not able to overcome their malig∣nity.

From hence then it follows, that, if any beast or bird prey upon some of another kind, there will be some smell a∣bout them, exceedingly noisom to all others of that kind:

and, not only to beasts of that same kind, but (for the same reason) even to others likewise, that have a correspondence and agreement of temper and constitution with that kind of beast, whose hurt is the original cause of this aversion. Which being assented to, the same reason holds to make those crea∣tures, whose constitutions and tempers consist of things re∣pugnant and odious to one another, be at perpetual enmity, and fly from one another at the first sight, or at least, the suf∣ferer from the more active creature: as we see among those men, whose unhappy trade and continual exercise it is to emp∣ty Jakeses, such horrid stinks are by time grown so conform∣able to their nature, as a strong perfume will as much offend them, and make them, as sick as such stinks would do another man bred up among perfumes; and a Cordial to their spirits is some noysome smell, that would almost poison another man. And thus, if in the breach of the Wolf or the steam coming from his body, any quality be offensive to the Lamb (as it may very well be, where there is so great a contrari∣ety of natures) it is not strange, that, at the first sight and ap∣proach of him, he should be distemper'd and flie from him; as one fighting Cock will do from another that hath eaten Garlike: and the same happens between the Weasel and the Toad, the Lion and the Cock, the Toad and the Spider; and several other creatures, of whom like enmities are report∣ed.

All which are caus'd in them, not by secret instincts, and Antipathies, and Sympathies, wherof we can give no account; (with the bare sound of which words most men pay themselvs, without examining what they mean): but by downright material qualities, that are of contrary natures, (as fire and water are); and are either begotten in them in their ori∣ginal constitution, or implanted afterwards by their conti∣nual food, which, nourishing them, changes their constitu∣tion to its complexion. And, I am perswaded, this would go so far, that, if one man were nourish'd continually with such meat (and greedily affected it) which another had aversion from; there would naturally follow much dislike be∣tween them: unless some superiour regard should master

this aversion of the sense. And I remember to have seen two notable examples of it One, in Spain, of a Gentleman that had a horrour to Garlike, who (though he was very subject to the impressions of beauty) could never wean himself from an aversion he had setled in him to a very handsome woman, that used to eat much Garlike; though, to win him, she forbore the use of that meat, which to her was the most savoury of all o∣thers. And the like I knew in England between two, where∣of one extremely loved Cheese, and the other as much hated it; and would fall into a strange agony, and be reduced (one would think) to the point of death, if by inadvertency or o∣thers trial of him, he had swallow'd never so little of what the other would have quitted all meats else to live up∣on.

And, not only such aversions, as spring from differences of complexions in the constitutions of several animals, cause these effects of fear and trembling, and flying from those that make such impressions; but even the seeing them angry and in fury doth the like: for, such passions alters the spirits; and they, issuing from the body of the animal in passion, cannot choose but be receiv'd by another in a different manner, than if they were of another temper. Then, if the one kind be agree∣able to their nature, the other must needs be displeasing. And this may be the reason, why Bees never sting such as are of a milde and gentle disposition; and will never agree with others, that are of a froward and angry nature: And the same one may observe among Dogs. And peradventure, a mans fantasie may be raised to such a height of fury, that the fiercest beast may be afraid to look on him, and cannot endure that those ma∣stering spirits, which stream out of the mans eye, should come into his; so much they distemper his fantasie: and therfore he will turn away from the man, and avoid him. Which discourse may be confirm'd, by sundry examples of Lions and Bears, that have run from angry and confident men; and the like. Since then, a man, that in his naturall hew, gives no distast, so much affrights fiercest beasts, when he puts on his threatning looks; 'tis no wonder that beasts, of a milder and softer nature, should have fear of him setled in

them, when they never saw him otherwise than angry, and working mischief to them. And, since their brood receive from their parents a nature easily moved to fear or anger, by the sight of what moved them; 'tis not strange, that, at the first sight, they should tremble or swell, according as the in∣ward wotion of the spirits affords:

Now, if this hath render'd the Birds in the wild Islands afraid of men, who otherwise would be indifferent to them; 'tis no marvel to see more violent effects in the Lambs aversion from the Wolf, or in the Larks from the Hobbey: since they peradventure have, over and above the hurt they use to do them, a deformity in their constitutions; and therfore, though a Lark will flie, as well from a man as from a Hobbey, yet be∣cause there is one cause more for his dislike against the Hobbey than against the man (namely the deformity of their consti∣tutions), he will flie into the mans hand, to avoid the Hawks talons.

To some of these causes all Antipathies may be reduced: and * 1.357 the like reason may be given for the Sympathies we see between some creatures. The little corporeities which issue from the one have such a conformity with the temper of the other, that it is therby moved to joyn it self to the body from whence they flow, and affects union with it in that way, as it receives the impression. If the smell please it, the beast will always be smelling at it: if the tast, nothing shall hinder it from feeding upon it, when it can reach it. The Fishermen upon the bank over against Newfound Land report, that there flocks about them a kind of Bird, so greedy of the Fishes livers, which they take there, as that, to come at and feed on them, they will suffer the men to take them in their hands; and not flie away, as long as any of their desired meat is in their eye: whence the French-men that fish there, call them Happe Foyes. The like power a certain Worm has with Nightin∣gales.

And thus you see, how they are strong impressions upon sense, and not any discouse of reason, that govern Beasts in their actions. For, if their avoiding men did proceed from any s••ga∣city in their nature, surely they would exercise it when they

see that, for a bit of meat, they incur their destruction: and yet, neither the examples of their fellows kill'd before their eyes in the same pursuit, not the blows which themselvs do feel, can serve them for warning, where the sense is so strongly affected; but as soon as the blow that removed them is passed, (if it miss killing or laming them), and they be gotten on wing again, they'l return to their prey, as eagerly and as confidently as if nothing were there to hinder them.

This then being the true reason of all Sympathy and Anti∣pathy; * 1.358 we cannot admit that any Beasts should love or hate one another, for any other cause, than some of those we have touched. All which are reduced to local motion, and to ma∣terial application of bodies of one nature, to bodies of ano∣ther; and are as well trasmitted to their young ones, as be∣gotten in themselvs.

And as the satisfying of their sense is more prevalent in the Happe Foyes, than the fear which from other grounds is begotten in their fantasy; and so makes them approach to what the other would drive them from: In like manner, any aversion of the fantasy may be master'd, not only by a more powerful agent upon the present sense; but also by assuefacti∣on, and bringing into the fantasy, with pleasing circumstances, that object which before was displeasing and affrightful to it. As we see that all sorts of Beasts or Birds, if they be taken young may be ••amed and will live quietly together. Dogs that are used to hunt and kill Deer, will live friendly with one that is bred with them; and that Fawn, which otherwise would have bin afraid of them, by such education grows confident and plays boldly with them. Of which we can no longer re∣main in doubt, if we will believe the story of a Tyger (ac∣counted the cruellest beast of all others); who, being shut up with a Deer, that had bin bred with him from a Kid and from his being a Whelp, and no meat given him, used means to break prison when he was half starved, ra∣ther than he would hurt his familiar friend. You will not suspect, that it was a moral consideration which made him so kind: but the Deer had never come into his fan∣tasie

accompanied with other circumstances, than of play or of warmth; and therfore hunger (which calls only the species of meat out of the memory into the fantasy) would never bring the Deer thither, for remedy of that passion.

And that which often happens to those men, in whom the fantasie only works, is not much unlike to this: among whom I have seen some frentick persons, that, if they be per∣swaded they are tyed and cannot stir from the place where they are, will lye still and make great complaints for their imprisonment; and not go a step to reach any meat or drink that should lie in sight near them, though they were never so much pressed with hunger or thirst. The reason is evident; for, the apprehension of being tyed is so strong in their fantasie, that their fantasie can send no spirits into other parts of their body, wherby to cause motion.

And thus the Deer was beholding to the Tyger's fantasie, not to his discourse of moral honesty, for his life. The like of this Tyger and Deer is to be seen every day in the Tower of Lon∣don: where, a little Dog, that was bred with a Lion from his birth, is so familiar and bold with him, that they not only sleep together, but somtimes the Dog will be angry with him, and bite him; which the Lion never resents from him, though any other Dog that is put to him he presently tears in pieces.

And thus we plainly see, how it comes about, that beasts may have strange aversions from things, which are of an annoy∣ing or destructive nature to them, even at the first sight of them; and again, may have great likings of other things, in a manner contrary to their nature: without needing to allow them reason, wherby to discourse and judge what is hurtful to them; or to instruct the Tyger we have spoken of, or Androdus's Lion, the duties of friendship and gratitude.

The Longing marks which are oftentimes seen in children, * 1.359 and remain with them all their life, seem to be an off∣spring of the same root or cause; but in truth, they proceed from another, though of kin to this: for, the operation of the seed is pass'd, when these Longing marks are imprinted,

the child being then already form'd and quickn'd: and they seem to be made suddenly, as by the print of a seal. Ther∣fore, to render the cause of them; let us consider another sym∣pathy, which is more plain and common. We see that the laugh∣ing of one man will set another on laughing, that sees him laugh; though he know not the cause, why the first man laughs; and the like we see in yawning and stretching, which breed the like effect in the looker on. I have heard of a man, that, seeing a roasted Pig, after our English fashion with the mouth gaping, could not shut his own mouth, as long as he look'd upon the Pigs: and of another, that, when he saw any man make a certain motion with his hand, could not choose but he must make the same; so that, being a Tyler by his Trade, and having one hand imploy'd with holding his tools, while he held himself with the other upon the eav's of a house, he was mending, a man standing below on the ground made that sign or motion to him wherupon he quited his holdfast to imi∣tate that motion, and fell down, in danger of breaking his neck.

All these effects proceed out of the action of the seen object, upon the fantasie of the looker on, which, making the picture or likeness of its own action in the others fantasie, makes his spirits run to the same parts; and consequenty, move the same members, that is, do the same actions. And hence it is, that, when we hear one speak with love and tender∣ness of an absent person, we are also inclined to love that per∣son, though we never saw nor heard of him before; and that whatever a good Oratour delivers well (that is, with a sem∣blance of passion agreeable to his words) raises, of its own nature, like affection in the hearers: aod that generally men learn and imitate (without design) the customs and manners of the company, they much haunt.

To apply this to our intent, 'tis easie to conceive, that, al∣though the child in the mothers wombe can neither see nor hear what the mother doth; nevertheless there cannot pass any great or violent motion in the mothers body, wherof some effect doth not reach to the child, which is then one continuate piece with her: and the proper effect of motion or

trembling in one body, being to produce a like motion or trembling in another, (as we see in that ordinary example of tuned strings, wherof one is moved at the striking of the other, by reason of the stroke given to the air, which, finding a movable easily moved with a motion of the same tenour, communicates motion to it); it follows, that the fantasie of the child being as it were well tuned to the fantasie of the mother, and the mothers fantasie making a special and very quick motion in her own whole body, (as we see sudden passions do), this motion or trembling of the mother must needs cause the like motion and trembling in the child, even to the very swiftness of the mothers motion. Now, as we see, when one blushes the blood comes into his face, so the blood runs in the mother to a certain place, where she is strucken by the thing long'd for: and the like hap'ning to the child, the violence of that sudden motion dyes the mark or print of the thing in the tender skin of it; the blood in some mea∣sure piercing the skin, and not returning wholly into its natu∣ral course: which effect is not permanent in the mother, be∣cause her skin, being harder, doth not receive the blood into it; but sends it back again; without receiving a tincture from it.

Far more easie is it, to discover the secret cause of many * 1.360 antipathies or sympathies, which are seen in children, and en∣dure with them, the greatest part, if not the whole term, of their life, without any apparent ground for them. As, some do not love Cheese, others Garlick, others Ducks; others divers other kinds of meat, which their parents loved well: and yet, in token that this aversion is natural to them, and not arising from some dislike accidentally taken and imprinted in their fantasie; they will be much harmed, if they chance to eat any such meat, though, by the much disguising it, they neither know, nor so much as suspect they have done so. The story of the Lady Hennage (who was of the Bed-chamber to the late Queen Elizabeth); that had her cheek blister'd by laying a Rose upon it, whiles she was asleep, to try if her antipathy a∣gainst that flower were so great, as she used to pretend, is fa∣mous in the Court of England. A Kinsman of mine, whiles

he was a Child, had like to have died of drought, before his Nurse came to understand, that he had an antipathy against Beer or Wine: till the tender nature in him, before he could speak, taught him to make earnest signs for water, that by ac∣cident he saw; the greedy drinking of which cured presently his long languishing and pining sickness. And such examples are very frequent.

The cause of these effects many times is, that their mothers, (upon their first suppression of their usual evacuations, by reason of their being with child) took some strong dislike to such things: their stomachs being then oppressed by unnatural hu∣mors, which overflow their bodies upon such retentions and make them oftentimes sick and prone to vomiting (especially in the mornings, whiles they are fasting) and somtimes to de∣sire earnestly (which they call longing) to feed upon some un∣wholsome, as well as some particular wholsome things; and o∣ther whiles, to take aversion against meats, which at other sea∣sons they affected well. Now, the child being nourished by the so-imbued blood of the mother; no wonder if it takes affections or dislikes, conformable to those which at that present reign in the mother. Which, for the most part, use to be purged away, or are overwhelmed by the mastering qualities of better aliments succeeding; but if, by some mischance, they become too much grafted in the childs stomach, or in some other part through which the masse of blood must pass, then the child gets an a∣version from those meats: and we often see, that persons retain a strong conversion to such meats or drinks, as their mothers affected much or longed for whiles they bred them.

And thus we will leave this particular; adding only one note, why there are more persons, generally, who have antipathy a∣gainst Cheese, than against any one sort of meat besides what∣ever. A principal reason of which symptome (where the prece∣dent one hath not place) I conceive to be that their nurses proved with child, whiles they gave them suck: for I have by experience found it to have been so, in as many as I have made inquiry into. And it is very conformable to reason: for the nurses milk crud∣ling in her brest upon her breeding of child, and becoming ve∣ry offensive to the childs tender stomach, (whose being sick,

obliges the Parents to change the Nurse, though peradven∣ture they know nothing of the true reason that makes her milk unnatural) he hath a dislike of Cheese (which is strong curd∣led milk) ever after setled in him, as people, that have once surfeited violently of any meat, seldom arrive to brock it a∣gain.

Now, as concerning those animals who lay up in store for winter, and seem therin to exercise a rational providence: who * 1.361 sees not, that it is the same humour, which moves rich misers to heap up wealth, even at their last gasp; when they have no child nor friend to give it to, nor think of making any body their heirs? Which actions, because they have no reason in them, are to be imputed to the passion or motion of the material appe∣tite. In the doing of them these steps may be observed; First the Object, presenting itself to the eye, provokes love and de∣sire of it; especially if it be joyn'd with the memory of for∣mer want: then, this desire stirs up the animal (after he hath fed himself) to gather into the place of his chief residence, as much of that desired object, as he meets with; and when ever his hunger returning brings back into his fantasy the memo∣ry of his meat, it being joyn'd with the memory of that place (if he be absent from it) he presently repairs thither for re∣lief of what presseth him; (and thus Dogs, when they are hun∣gry, rake for bones they had hidden when their bellies were full.) Now, if this food, gathered by such providence (which is nothing else but the conformity of it, working upon him by his sense) and layed up in the place where the owner of it resides, (as the Corn is, which the Ants gather in Summer) be easily portable; he will carry it abroad with him, the first time he stirs after a long keeping in: for then nothing works so powerfully in his fantasy, as his store; and he will not easily part from it, though other circumstances invite him abroad. From hence it proceeds, that. when a fair day comes after long foul weather, the Ants, who all that while kept close in their Dens with their Corn lying by them, then come abroad in the Sun, and carry their Grain along with them: or peradventure it happens, because the precedent wet weather hath made it grow hot, or musty, or other∣wise

offensive within; and therfore they carry it out, as soon as themselvs dare peep abroad, which is, when the fair wea∣ther and heat of the day invites them out into the open air: and, before night, that they return into their holes, the offen∣sive vapours of the corn are exhaled and dryd up, and move their fantasies no longer to aversion; wherupon they carry it back again, having then nothing but their long contracted love to it, to work upon them. The like wherof men doing by discourse, to air their corn and keep it sweet, and the same effect following therin; they will presently have it, that this is done by the Ants for the same reason, and by design. Then, the moisture of the earth swelling the grain, and consequently, making it begin to shoot at the ends, (as we declared, when we spoke of the generation of Plants, and as we see in the moist∣ning of Corn to make Malt of it) those littte creatures, find∣ing that part of it more tender and juicy, than the rest, nibble upon it there, and feed themselvs first with that, which con∣sequently hinders the growth of the corn. And here a∣gain, men will contend that this must be done by providence and discourse; to prevent, that their store should not grow out of their reach and changing nature, become useless to them in their need.

To conclude, the Foreknowing of Beasts is nothing else, but their timely receiving impressions, from the first degrees of * 1.362 mutations in things without them: which degrees are almost im∣perceptible to us, because our fantasies & spirits have otherwise such violent agitations, more than theirs; which hinder them from discerning gentle impressions upon them. If you be at Sea, after a long calm, a while before a gale blows to fill your Sails, or to be discernible by your sense in quality of wind, you shall perceive the Sea begin to wrinkle his smooth face that way the wind will come: which is so infallible a sign that a gale will come from that coast, as mariners immediately fall to triming their sailes accordingly; and usually, before they can have done, the wind is with them; shall we therfore saythat the Sea hath a providence, to foresee which way the wind will blow? or that the corns upon our toes, or calluses, or broken bones, or joints that have been dislocated, have discourse & can fore∣tell

the weather? 'Tis nothing else, but that the wind rising by degrees, the smooth Sea is capable of a change by it, before we can feel it: and that the Air, being changed by the forerun∣ners of worse weather, works upon the crasiest parts of our body, when the others feel not so small a change. So beasts are more sensible, than we (for they have less to distract them) of the first degrees of a changing weather: and that mutation of the air without them makes some change within them, which they express by some outward actions or gestures.

Now, they who observe how such mutations and actions are constantly in them, before such or such weather, think they know beforehand, that rain (for example) or wind, or drought is coming; according to the several signs they have mark'd in them. Which proceeds out of the narrowness of their dis∣course; that makes them resort to the same causes, when ever they meet with like effects: and so they conceive, that things must needs pass in Beasts, after the same tenour, as they do in men. And this is a general and main errour, runing through all the conceptions of mankind, (unless great heed be taken to prevent it, that, what subject soever they speculate on, whe∣ther it be of substances that have a superiour nature to theirs, or of creatures inferiour to them; they are still apt to bring them to their own standard, and to frame such conceptions of them, as they would do of themselvs: As, when they will have Angels discourse, and move, and be in place, in such sort as is natural to men; or when they will have beasts ratiocinate and understand, upon their observing some orderly actions per∣form'd by them, which in men would proceed from discourse and reason. And this dangerous Rock (against which many fine conceptions suffer shipwrack) whoever studies truth must have a main caution to avoid.

Sed nos immensum spatiis confecimus aequor: Et jam tempus equum fumantia solvere colle.

Notes

• * 1.1

  1 Quantity is the first and most obvious affe∣ction of a Body.
• * 1.2

  2 Words do not express things as they are in themselvs, but only as they are painted in the minds of men.
• * 1.3

  3 The first error that may arise from hence, which is a multiplying of Things, where no such multiplication is really found.
• * 1.4

  4. A second er∣rour; the con∣ceiving of many distinct things, as re∣ally one thing.
• * 1.5

  5. Great care to be taken, to avoid the er∣rours which may arise from our manner of understanding things.
• * 1.6

  Two sorts of words to ex∣press our noti∣ons; the one common to all men, the other proper to Scholars.
• * 1.7

  7. Great errours arise, by wre∣sting words from their common mea∣ning, to ex∣press a more particular or studied notion
• * 1.8

  1. We must know the vulgar and common notion of Quantity, that we may un∣derstand the nature of it.
• * 1.9

  2. Extension or Divisibility is the common notion of Quantity.
• * 1.10

  3 Parts of Quantity are not actually in their whole.
• * 1.11

  4 If parts were actually in their whole, Quantity would be com∣posed of indi∣visibles.
• * 1.12

  5. Quantity can∣not be compo∣sed of indivi∣sibles.
• * 1.13

  6 An objection to prove that parts are actu∣ally in Quan∣tity; with a declaration of the mistake from whence it proceed.
• * 1.14

  7 The solution of the former objection: and that Sense and not discern whether one part be distin∣guish'd from another, or no.
• * 1.15

  Chap 〈◊〉〈◊〉. 8. 2. 3.
• * 1.16

  8. An enumerati∣on of the seve∣ral specieses of Quantity; which confirms that the essente of it is divisibi∣litie.
• * 1.17

  1: What is meant by Rarity and Densitie.
• * 1.18

  2. 'Tis evident that some bo∣dies are rare and others dense; though obscure, how they are such.
• * 1.19

  3. A brief enu∣meration of the several properties be∣longing to rare and dense bodies.
• * 1.20

  4. The opinion of those Philo∣sophers decla∣red, who put Rarity to con∣sist in an actu∣al division of a Body into lit∣tle parts.
• * 1.21

  5. The former opinion re∣jected, and the ground of their errour discover'd.
• * 1.22

  6 The opinion of those Phi∣losophers re∣lated, who put Rarity to con∣sist in the mix∣tion of Vacuity among bo∣dies.
• * 1.23

  The opinion of Vacuities refu∣ted.
• * 1.24

  Dialog. 1. del. Movim. pag. 18.
• * 1.25

  Archimed▪ promot.
• * 1.26

  8. Rarity and Density consist in the severall proportions, which Quan∣tity hath to its Substance.
• * 1.27

  9. All must ad∣mit, in Physi∣cal bodies, a Metaphysical composition.
• * 1.28

  1. The notions of density and ra∣rity have a la∣titude capable of infinite va∣riety.
• * 1.29

  2. How m••istness and dryness are begotten in dense bo∣dies.
• * 1.30

  3. How moistness and drieess are begotten in rare bodies.
• * 1.31

  4. Heat is a pro∣pertie of rare bodies, and cold of dense ones.
• * 1.32

  5. Of the two dense bodies, the less dense is more cold: but of the two rare ones, the less rare is less hot.
• * 1.33

  6 The extreme dense body is more dry then the extreme rare one.
• * 1.34

  7. There are but four simplebo∣dies: and these are rightly named Ele∣ments.
• * 1.35

  8 The Author doth not de∣termine whe∣ther every Element com∣prehends un∣der its name one only low∣er species, or many: nor whether any of them be found pure.
• * 1.36

  1. The first ope∣ration of the Elements is division, out of which resul∣reth local mo∣tion.
• * 1.37

  What place is, both notional∣ly and really.
• * 1.38

  3. Locall motion is that divisi∣on, whereby a body changes its place.
• * 1.39

  4. The nature of quantity of it self is suffici∣ent to unite a body to its place.
• * 1.40

  5. All operations amongst bo∣dies, are either local motion or such as fol∣low out of lo∣cal motion.
• * 1.41

  6. Earth compa∣red to water in activity.
• * 1.42

  S. 6.
• * 1.43

  7. The manner whereby fire gets into fewel, proves that it exceeds earth in acti∣vity.
• * 1.44

  8. The same is proved by the manner, wher∣by fire comes out of fewel and works upon other bodies.
• * 1.45

  1. In what sense the Author rejects Qua∣lities.
• * 1.46

  In what sense the Author ad∣mits of qua∣lities.
• * 1.47

  3. Five argu∣ments propo∣sed to prove that light i•• not a body.
• * 1.48

  4. The two first reasons to prove light a body are, the resemblance it hath with fire; and be∣cause, if it were a quali∣ty, it would always pro∣duce an equall to it self.
• * 1.49

  5. The third reason; because if we imagine to our selves the substance of fire to be rarified, it will have the s••me appearances which light hath.
• * 1.50

  6. The fourth reason, from the manner of the generation and corrupti∣on of light; whcih agrees with fire.
• * 1.51

  7. The fifth rea∣son; because such proper∣ties belong to light as agree only to bodies.
• * 1.52

  1. That all light is hot and apt to heat.
• * 1.53

  2. The reason why our bodies for the most part do not feel the heat of pure light.
• * 1.54

  3. The experi∣ence of bur∣ning glasses, and of soultry gloomy wea∣ther prove light to be fire.
• * 1.55

  4. Philosophers ought not to judge of things by the rules of vulgar people.
• * 1.56

  5. The different names of light and fire pro∣ceed from dif∣ferent notions of the same substance.
• * 1.57

  6.
• * 1.58

  The reason why many times fire and head are de∣prived of light.
• * 1.59

  7. What becoms of the body of light when it dies.
• * 1.60

  8. An experi∣ment of some who petend, that light may be preci∣pitated into powder.
• * 1.61

  9. The Authors opinion con∣cerning lamps pretended to have been found in Tombes, with inconsumpti∣ble lights.
• * 1.62

  1. Light is not really in every part of the room it en∣lightens, nor fills entirely any sensible part of it, though it seem to us to do so.
• * 1.63

  2. The least sen∣sible point of a diaphanous body hath room sufficient to contain both air and light, together with a multi∣tude of beams issuing from several lights, without pene∣trating one another.
• * 1.64

  Willibrord Snell.
• * 1.65

  3. That light doth not en∣lighten any room in an in∣stant; and that the great cele∣rity of its mo∣tion doth make it im∣perceptible to our senses.
• * 1.66

  4. The reason why the mo∣tion of light is not discern'd coming to∣wards us; and that there is some reall tar∣dity in it.
• * 1.67

  5. The Planets are not cer∣tainly ever in that place where they appear to be.
• * 1.68

  6. The reason why light be∣ing a body, doth not by its motion shatter other bodies into pieces.
• * 1.69

  7. The reason why the body of light is ne∣ver perceiv'd to be fanned by the wind.
• * 1.70

  The reasons for and against lights being a body compa∣red together.
• * 1.71

  A summary re∣petition of the reasons which prove that light is fire.
• * 1.72

  1. No local mo∣tion can be perform'd without suc∣cession.
• * 1.73

  2. Time is the common mea∣sure of all suc∣essione.
• * 1.74

  3 What velocity is, and that it cannot be in∣finite.
• * 1.75

  4. No force so little that is not able to move the greatest weight imagi∣nable.
• * 1.76

  5. The chief principle of Mechanicks deduced out of the former discourse.
• * 1.77

  6. No moveable can passe from rest to any de∣terminate de∣gree of veloci∣ty, or from a lesser degree to a greater; without pas∣sing through all the inter∣mediate de∣grees, which are below the obtained de∣gree.
• * 1.78

  7. The conditi∣ons which help to moti∣on, in the mo∣vable are three; in the medium one.
• * 1.79

  Dialog. 1. of Motion.
• * 1.80

  8. No body hath any intrinse∣cal vertue to move it self towards any determinate part of the Universe.
• * 1.81

  9. The encrease of motion is always made in the propor∣tion of the odd numbers.
• * 1.82

  10. No motion can encrease for ever, with∣out coming to a period.
• * 1.83

  11. Certain pro∣blems resol∣ved concern∣ing the pro∣portion of some moving agents com∣pared to their effects.
• * 1.84

  12. When a move∣able comes to rest, the mo∣tion decreases according to the rules of encrease.
• * 1.85

  1. Those moti∣ons are call'd natural which have constant causes; and those violent which are contrary to them.
• * 1.86

  2. The first and most general operation of the Sun is, the making and raising of atomes.
• * 1.87

  3. The light, re∣bounding from the earth with atomes, causes two streams in the air; the one ascending, the other descend∣ing; and both of them in a perpendicular line.
• * 1.88

  4. A dense body, placed in the air between the ascending and descen∣ding streams must needs descend.
• * 1.89

  5. A more parti∣cular explica∣tion of all the former do∣ctrine touch∣ing Gravity
• * 1.90

  6. Gravity and levity do not signifie an in∣trinsecal in∣clination to such a motion, in the bodies themselvs which are term'd heavy and light.
• * 1.91

  7. The more dense a body is, the more swiftly it des∣cends.
• * 1.92

  8. The velocity of bodies des∣cending doth not encrease, in proportion to the diffe∣rence that may be be∣tween their se∣veral densities.
• * 1.93

  9. More or less gravity pro∣duces a swist∣er or a slower descending a heavy body. Aristotles ar∣gument, to disprove mo∣tion in 〈◊〉〈◊〉, is made good.
• * 1.94

  10. The reason why, at the in∣ferior quarter of a circle, a body descends faster by the arch of that quarter, then by the chord of it.
• * 1.95

  1. The first obje∣ction answer∣ed; why a hol∣low body descends flow∣er then a so∣lid one.
• * 1.96

  2: The second objection an∣swer'd; and the reasons shown why atoms conti∣nually over∣take the des∣cending dense body.
• * 1.97

  3. A curious que∣ston left un∣decided.
• * 1.98

  4. The fourth objection an∣swer'd; Why the descent of the same heavy bodies is equal in so great inequa∣lity of the a∣toms which cause it.
• * 1.99

  5. The reason why the shel∣ter of a thick∣body doth not hinder the de∣scent of that which is un∣der it.
• * 1.100

  6. The reason why some bo∣dies sink, others swims.
• * 1.101

  7. The fifth ob∣jection an∣swer'd, con∣cerning the descending of heavy bo∣dies in streams.
• * 1.102

  8. The sixth ob∣jection answe∣red: and that all heavy Ele∣ments do weigh in their own Spheres.
• * 1.103

  9▪ The seventh objection an∣swer'd, and the reason why we do not feel the course of the air and atoms that beat con∣tinually upon us.
• * 1.104

  10. How, in the some body, gravity may be greater than density, and density than gravity; though they be the same thing.
• * 1.105

  11. The opinion, of gravities being an in∣trinsecal in∣clination of a body to the centre, refuted by reason.
• * 1.106

  ••2. The same opi∣nion refuted by several ex∣periences.
• * 1.107

  1. The State of the question touching the cause of vio∣lent motion.
• * 1.108

  2 That the me∣dium is the only cause, which conti∣nues violent motion.
• * 1.109

  3. A further ex∣plication of the former Doctrine.
• * 1.110

  4. That the air has strength enough to continue vio∣lent motion in a move∣able. Dial. 1. of motion, pag. 98.
• * 1.111

  5. An answer to the first obje∣ction; that air is not apt to conserve mo∣tion. And how violent moti∣on comes to cease.
• * 1.112

  6. An answer to the second objection, that the air has no power over heavy bodies.
• * 1.113

  7. An answer to the third ob∣jection, that an arrow should fly fa∣ster broadways than long ways
• * 1.114

  1. That reflecti∣on is a kind of violent moti∣on.
• * 1.115

  2. Reflection is made at equal angles.
• * 1.116

  3. The causes and properties of Undulation
• * 1.117

  4. Refraction at the entrance into the refle∣ctent body is towàrds the perpendicu∣lar, at the go∣ing out is from it; when the second su∣perficies is pa∣rallel to the first.
• * 1.118

  5. A refutation of Monsir des Cartes his ex∣plication of ••efraction.
• * 1.119

  6.
• * 1.120

  An answer to the arguments brought in fa∣vovr of Monsir des Cartes his opinion.
• * 1.121

  7. The true cause of refraction of light, both at its entrance and at its go∣ing out, from the reflecting body.
• * 1.122

  8. A general rule to know the nature of reflections and refractions in all sorts of surfaces.
• * 1.123

  9. A body of greater parts and greater pores makes a greater refra∣ction, than one of lesser parts and les∣ser pores.
• * 1.124

  10. A confirmati∣on of the for∣mer doctrine, out of the na∣ture of bodies that refract light.
• * 1.125

  1. The connexi∣on of this Chapter with the rest, and the Authors intent in it.
• * 1.126

  2. That there is a least size of bodies, And that this least size is found in fire.
• * 1.127

  3. The first con∣junction of parts is in bo∣dies of least size; and it is made by the force of Quantity.
• * 1.128

  4. The second sort of con∣junction ••s compactedness in simple Ele∣ments, and it proceeds from Density.
• * 1.129

  5. The third conjunction is of parts of dif∣ferent Ele∣ments; and it proceeds from quantity and density toge∣ther.
• * 1.130

  6. The reason why liquid bodies, easily joyn together, and dry ones difficultly.
• * 1.131

  7. That no two hard bodies can touch one another im∣mediately.
• * 1.132

  8. How mixed bodies are fra∣med in gene∣ral.
• * 1.133

  9. The cause of the several degrees of so∣lidity in mix∣ed bodies.
• * 1.134

  10. The rule whereto are reduced all the several combinations of Elements in compound∣ing of mixed bodies.
• * 1.135

  11. Earth and wa∣ter are the Basis of all permanent mixed bodies.
• * 1.136

  12. What kind of bodies those are, where wa∣ter is the Basis and earth the pedominant element over the other two.
• * 1.137

  13. Of these bo∣dies where, water bing the B sis, air is the predomi∣nant Element
• * 1.138

  14. What kind of bodies result, where water is the Basis, and fire the predo∣minant Ele∣ment.
• * 1.139

  15. Of those bo∣dies, where water is in ex∣cess; it alone being both the Basis, and the predomi∣nant Element:
• * 1.140

  16. Of those bo∣dies were Earth alone is the Basis, and also the pre∣dominant in excess over the other three Ele∣ments.
• * 1.141

  17. Of those bo∣dies where Earth is the basis, and Wa∣ter the predo∣minant Ele∣ment over the other two.
• * 1.142

  18. Of those bo∣dies where, earth being the basis, air is the predomi∣nant.
• * 1.143

  19. Of those bo∣dies where, earth being the basis, fire is the predomi∣nant.
• * 1.144

  20. All the Se∣cond Quali∣ties of mixed bodies arise from several combinations of the First Qualities; and are at last re∣solv'd into se∣veral degrees of rarity and density.
• * 1.145

  21. That in the Planets and Stars there is a like variety of mixed bo∣dies caused by light, as here upon Earth.
• * 1.146

  22. In what man∣ner the Ele∣ments work upon one ano∣ther, in the position of mixed bodies: and in parti∣cular, fire is the most active.
• * 1.147

  23. A particular declaration, touching the generation of Metals.
• * 1.148

  1. Why some bo∣dies are brittle and others tough or apt to withstand outward vio∣lence, the first instrument to dissolve mixed bodies.
• * 1.149

  2. How outward violence work upon the most com∣pacted bodies.
• * 1.150

  3. The several effects of fi••e, the second and chiefest instru∣ment to dis∣solve com∣pounded bo∣dies.
• * 1.151

  4. The reason why some bo∣dies are not dissolv'd by fire.
• * 1.152

  5. The reason why fire melts gold, but cannot consume it.
• * 1.153

  6. Why Lead is easily consu∣med and cal∣cined by fire.
• * 1.154

  7. Why and how some bodies are divided by fire into spi∣rits, waters, oyls, salts, and earth; & what those parts are.
• * 1.155

  〈◊〉〈◊〉 How water, the third in∣strument to dissolve bo∣dies, dissolves Calx into Salt. and so into Terra damnata,
• * 1.156

  9. How water mingled with salt, becomes almost power∣full Agent to dissolve other bodies.
• * 1.157

  20. How putrefa∣ction is caused
• * 1.158

  1. What is the Sphere of Activity in corporeal Agents.
• * 1.159

  2. The reason why no body can work in distance.
• * 1.160

  3. An objection answer'd a∣gainst the manner of ex∣plicating the former Axi∣ome.
• * 1.161

  4 Of reaction; and first, in pure local motion, that each Agent must suffer in acting and act in suffering.
• * 1.162

  5. The former doctrine ap∣plyed to other local motions design'd by particular names. And that Suisseths argument is of no force against this way of do∣ctrine.
• * 1.163

  6. Why some no∣tions admit of intension and remission; and others not.
• * 1.164

  7. That in every part of our habitable world, all the four Elements are found pure in smal atoms; but not in any great bulk.
• * 1.165

  1. The Authors intent in this and the fol∣lowing chap∣ters:
• * 1.166

  Mr. Thomas White.
• * 1.167

  2. That bodies may be rarifi∣ed, both by outward and inward heat; and how this is perform'd.
• * 1.168

  3. Of the great effects of Ra∣refaction.
• * 1.169

  4. The first man∣ner of conden∣sation, by heat
• * 1.170

  5. The second manner of condensation, by cold.
• * 1.171

  3. That Ice is not water ra∣rifi••d, but condensed.
• * 1.172

  7. How wind, snow, and hail are made; and wind by rain allayed.
• * 1.173

  8. How parts of the same or divers bo∣dies are joyned more strongly toge∣ther by con∣densation.
• * 1.174

  9. Vacuities can∣not be the reason why water, impreg∣nated to the full with one kind of salt, will notwith∣standing re∣ceive more of another.
• * 1.175

  10. The true rea∣son of the for∣mer effect.
• * 1.176

  11. The reason why bodies of the same na∣ture j••yn more easily together then others,
• * 1.177

  1. What attracti∣on is, and from whence it proceeds.
• * 1.178

  1. The true sense of the Maxime, that Nature abhors from vacuity.
• * 1.179

  3. The true rea son of attra∣ction.
• * 1.180

  4. Water may be brought by the force of attraction to what height soever.
• * 1.181

  5. The doctrine touching the attraction of water in Sy∣phons.
• * 1.182

  6. That the Sy∣phon doth not prove water to weigh in its own orb.
• * 1.183

  7. Concerning attraction caused by fire.
• * 1.184

  8. Concerning attraction made by vir∣tue of hot bo∣dies, amulets, &c.
• * 1.185

  9. The natural reason given for divers ope∣rations, estee∣med by some to be magical.
• * 1.186

  1. What is Fil∣tration; and how it is effe∣cted.
• * 1.187

  2. What causes the water in filtration to ascend.
• * 1.188

  3. Why the fil∣ter will not drop, unless the label hang lower then the water.
• * 1.189

  4. Of the motion of R••stitution: and why some bodies stand bent, others not.
• * 1.190

  5. Why some bo dies return only in part to their natu∣ral figure; o∣thers entirely.
• * 1.191

  6. Concerning the nature of those bodies which shrink and stretch.
• * 1.192

  7. How great & wonderful ef∣fects proceed from smal, plain, and sim∣ple principles.
• * 1.193

  8. Concerning Electrical at action, and the causes of it.
• * 1.194

  6. Cabeus his o∣pinion re••u∣ted, concern∣ing the cause of Electrical motions.
• * 1.195

  1. The extreme heat of the Sun under the Zodiack, draws a stream of air from each pole into the Torrid Zone.
• * 1.196

  Chap. 18. Sect. 7.
• * 1.197

  2. The Atoms of these two streams com∣ing together are apt to in∣corporate with one another.
• * 1.198

  3. By the meet∣ing and ming∣ling together of these streams at the Equator, divers rivolets of Atoms of each Pole are con∣tinuated from one Pole to the other.
• * 1.199

  4. Of these A∣toms, incorpo∣rated with some fit mat∣ter in the bowels of the earth, is made a stone.
• * 1.200

  5. This stone works by ema∣nations joyn∣ed with agree∣ing streams that meet them in the air; and in fine it is a Load∣stone.
• * 1.201

  6 A methode for making experiences on any sub∣ject.
• * 1.202

  7. The Load∣stones genera∣tion, by atoms flowing from both Poles, is confirmd by experiments observ'd in the stone it self.
• * 1.203

  8. Experiments to prove that the Loadstone works by ema∣nations meet∣ing with agreeing streames.
• * 1.204

  1. The operati∣ons of the loadstone are wrought by bodies and not by qualities.
• * 1.205

  2. Objections a∣gainst the for∣mer position answer'd.
• * 1.206

  3. The Load∣stone is imbu∣ed with his virtue, from another body.
• * 1.207

  4: The virtue of the Loadstone is a double, and not one simple virtue.
• * 1.208

  5. The virtue of the Loadstone works more strongly in the poles of it, then in a∣ny other part.
• * 1.209

  6. The loadstone sends forth its emanations spherically. Which are of two kind••: and each kind is strongest in that Hemi∣sphere, through whose polary parts they is∣sue out.
• * 1.210

  7. Putting two loadstones within the sphere of one another, every part of one loadstone doth not agree w••th every part of the other load∣stone.
• * 1.211

  8. Concetning the declinati∣on and other respects of a needle, to∣wards the loadstone it touches.
• * 1.212

  8. The virtue of the Loadstone goes from end to end, in lines almost parallel to the Axis.
• * 1.213

  10. The virtue of the Loadstone is not perfect∣ly spherical, though the stone be such.
• * 1.214

  11. The intention of nature, in all the opera∣tions of the loadstone, is to make an union betwixt the attractive and attracted bodies.
• * 1.215

  12. The main globe of the earth is not a Loadstone.
• * 1.216

  13. The loadstone is generated in all parts or Clim••t's of the earth.
• * 1.217

  14. The confor∣mity betwixt the two moti∣ons of mag∣netick things, and of heavy things.
• * 1.218

  1. Which is the North, and which the South Pole of a Loadstone.
• * 1.219

  2. Whether any bodies, besides magnetick ones, be attra∣ctive.
• * 1.220

  3. Whether an iron, placed perpendicu∣larly towards the earth, gets a magnetical virtue of pointing to∣wards the north, or to∣wards the south, in that end that lies downwards.
• * 1.221

  4. Why load∣stones affect iron better than one ano∣ther.
• * 1.222

  5. Gilberts reason refuted touching a cap'd Load∣stone, that takes up more iron then one not cap'd; and an iron impregnated that, in some case, draws more strongly then the stone it self.
• * 1.223

  Galileus his opinion touching the former effects refuted.
• * 1.224

  7. The Authors solution to the former questions.
• * 1.225

  8. The reason why, in the former case, a lesser Load∣stones draws the interja∣cent iron from the greater.
• * 1.226

  9. Why the vari∣ation of a touched nee∣dle from the North is grea∣ter, the nearer you go to the Pole.
• * 1.227

  10. Whether, in the same part of the world, a touched nee∣dle may it one time vary more f••om the North, and at another time less.
• * 1.228

  11. The wh••le doctrine of the lo••dstone sum'd up in short.
• * 1.229

  1. The connexi∣on of the fol∣lowing Chap∣ters with the precedent ones.
• * 1.230

  2. Concerning several com∣positions of mixed bodies.
• * 1.231

  3. Two sorts of Living Crea∣tures.
• * 1.232

  4. An engine to express the first sort of li∣ving creatures.
• * 1.233

  5. Another En∣gine by which may be expres∣sed the second sort of living creatures.
• * 1.234

  4. The two for∣mer engines and some o∣ther compari∣sons applied, to express the two several sorts of living creatures.
• * 1.235

  7. How plants are framed.
• * 1.236

  8. How Sensitive Creatures are formed.
• * 1.237

  1. The opinion that the seed contains for∣mally every part of the pa∣rent.
• * 1.238

  2. The former opinion re∣jected.
• * 1.239

  3. The Authours opinion of this question.
• * 1.240

  4. Their opinion refuted, who hold that eve∣ry thing con∣tains formally all things.
• * 1.241

  5. The Authors opinion con∣cerning the generation of Animals de∣clared and confirm'd.
• * 1.242

  That one sub∣stance is chan∣ged into ano∣ther.
• * 1.243

  7. Concerning the hatching of Chickens, and the generation of the other Animals.
• * 1.244

  8. From whence it happens, that the defi∣ciences or ex∣cresences of the parents body are often seen in their children.
• * 1.245

  9. The difference between the Authors opi∣nion, an•• ••he former 〈◊〉〈◊〉.
• * 1.246

  10 That the heart is imbued with the general specifike ver∣tues of the whole body: wherby is confirm'd the doctrine of the two former Paragraphes.
• * 1.247

  11 That the heart is the first part genera∣ted in a living creatures.
• * 1.248

  1. That the fi∣gure of an Animal is produced by ordinary se∣cond causes, as well as any other corpore∣al effect.
• * 1.249

  2. That the seve∣ral figures of bodies pro∣ceed from a defect in one of three di∣mensions; caused by the circumference of accidental causes.
• * 1.250

  3. The former doctrine is confirmd by several instan∣ces.
• * 1.251

  4. The same do∣ctrine applyed to plants.
• * 1.252

  4. The same do∣ctrine decla∣red in leaves of trees.
• * 1.253

  16. The same ap∣plied to the bodies of Ani∣mals.
• * 1.254

  7. In what sense the Author admits of, vis formatrix.
• * 1.255

  1. From whence proceeds the primary moti∣on & growth in Plants.
• * 1.256

  2. Mr. des Cartes his opinion touching the motion of the heart.
• * 1.257

  3. The former opinion reje∣cted.
• * 1.258

  4. The Authors opinion con∣cerning the motion of the heart.
• * 1.259

  5. The motion of the heart de∣pends origi∣nally of its fibers irrigated by bloud.
• * 1.260

  6. An objection answer'd a∣gainst the for∣mer doctrine.
• * 1.261

  7. The Circula∣tion of the Bloud, and other effects that follow the motions of the heart.
• * 1.262

  8. Of Nutrition.
• * 1.263

  9. Of Argumen∣tation,
• * 1.264

  10. Of Death and Sickness.
• * 1.265

  1. The connxei∣on of the sub∣sequent chap∣ters with the precedent.
• * 1.266

  2. Of the Senses and sensible qualities in general: And, of the end for which they serve.
• * 1.267

  3. Of the sense of Touching; and that both it and its qua∣lities are bo∣dies.
• * 1.268

  4. Of the Tast and its quali∣ties: that they are bodies.
• * 1.269

  5. That the Smell and its qualities are real bodies.
• * 1.270

  6. Of the confor∣mity betwixt the two Sen∣ses of Smelling and Tasting.
• * 1.271

  7. The reason why the sense of Smelling is not so per∣fect in man as in beasts: with a wonderful history of a man who could wind a scent as a well as any beast.
• * 1.272

  1. Of the sense of Hearing: and that Sound is purely motion.
• * 1.273

  2. Of divers arts belonging to the sense of Hearing: all which con∣firm that Sound is nothing but motion.
• * 1.274

  3. To same is confirm'd by the effects cau∣sed by great noises.
• * 1.275

  4. That solid bo∣dies may con∣vey the moti∣on of the ayr or sound to the organ of hearing.
• * 1.276

  5. Where the motion is in∣terrupted, there is no sound.
• * 1.277

  6. That not only the motion of the air, but all other motions coming to our ears, make sounds.
• * 1.278

  7. How own sense may sup∣ply the want of an other.
• * 1.279

  4. Of one who could discern sounds of words with his eyes.
• * 1.280

  9. Divers reasons to prove sound to be nothing else but a mo∣tion of some real body.
• * 1.281

  1. That Colours are nothing but light mingled with darkness; or the disposition of a bodies su∣perficies, apt to reflect light so mingled.
• * 1.282

  2. Concerning the disposition of those bo∣dies, which produce white or black cou∣lours.
• * 1.283

  3. The former doctrine con∣firm'd by Aristotles au∣thority, reason, & experience.
• * 1.284

  4. How the di∣versity of co∣lours follows out of various degrees of ra∣rity and den∣sity.
• * 1.285

  5. Why some bo∣dies are Dia∣phanous, o∣thers Opa∣cous.
• * 1.286

  6. The former doctrine of co∣lours con∣firm'd by the generation of white and black in bo∣dies.
• * 1.287

  1. Apparitions of colours through a Prism, or tri∣angular-glass, are of two sorts.
• * 1.288

  2. The several parts of the object make several angles at their en∣trance into the Prism.
• * 1.289

  6 The reason why somtimes the same ob∣ject appears through the Prism in two places; and in one place mor lively, in the other place more dim.
• * 1.290

  4 The reason of the various colours that appear in loo∣king through a Prism.
• * 1.291

  5. The reason why the Prism in one positi∣on, may make the colours ap∣pear quite contrary to what they did, when it was in another posi∣tion.
• * 1.292

  6. The reason of the various co∣lours in gene∣ral, by pure light passing through a Prism.
• * 1.293

  7. Upon what side every co∣lour appears, this is made by pure light passing through a Prism.
• * 1.294

  1. The reason of each several colour in par∣ticular caused by light pas∣sing through a Prism.
• * 1.295

  〈◊〉〈◊〉. 〈◊◊◊◊〉〈◊◊◊◊〉 ••∣ing the Prism▪
• * 1.296

  3 Of the Rain∣bow; and how, by the colour of any body, we may know the compositi∣on of the body it self.
• * 1.297

  4 That all the Sensible Qualities are real bodies, resulting out of several mixtures of Rarity and Density.
• * 1.298

  5 Why the Sen∣ses are only Five in num∣ber, with a conclusion of all the former doctrine con∣cerning them.
• * 1.299

  1. Monsir des Car∣tes his opini∣on touching Sensation.
• * 1.300

  2. The Authors opinion tou∣ching sensa∣tion.
• * 1.301

  3. Reasons to perswade the Authors opi∣nion.
• * 1.302

  4. That Vital Spirits are the immediate in∣struments of Sensation, by conveying sensible quali∣ties to the brain.
• * 1.303

  5. How found is convey'd to the brain by vital spirits.
• * 1.304

  6. How colours are convey'd to the brain by Vital Spi∣rits.
• * 1.305

  7. Reasons a∣gainst Monsir des Cartes his opinion.
• * 1.306

  8. That the sym∣ptome, of the Palsie do no way confirm Monsir des Car∣tes his opini∣on.
• * 1.307

  9. That M••asir des Cartes his opinion can∣not give a good account how things are conserv'd in the Memo∣ry.
• * 1.308

  1. How things are conserv'd in the Memo∣ry.
• * 1.309

  2. How things conserv'd in the Memory are brought back into the Phantasie.
• * 1.310

  3. A Confirmati∣on of the for∣mer doctrine.
• * 1.311

  4. How things renew'd in the fantasie re∣turn, with the same circum∣stances they had at first.
• * 1.312

  5: How the me∣mory of things past is lost, or confounded: and how it is repair'd again.
• * 1.313

  1. Of what mat∣ter the brrain is composed.
• * 1.314

  2. What is vo∣luntary mo∣tion.
• * 1.315

  3. What those powers are which are cal∣led Natural Faculties.
• * 1.316

  4. How the At∣tractive and Secretive fa∣culties work.
• * 1.317

  5. Concerning the concoctive faculty.
• * 1.318

  6. Concerning the Retentive and Expulsive faculties.
• * 1.319

  7. Concerning expulsion made by Phy∣sick.
• * 1.320

  9. How the brain is moved to work Volun∣tary motion.
• * 1.321

  9. Why pleasing objects dilate the spirits, and displeasing ones contract them.
• * 1.322

  10. Concerning the Five Sen∣ses, of what Use and End they are.
• * 1.323

  1. That 〈◊〉〈◊〉 Luc dum is the seat of the fan∣sie.
• * 1.324

  2. What causes us to remem∣ber, not only the object it self, but also that we have thought of it before.
• * 1.325

  3. How the mo∣tions of the fantasie are derived to the heart.
• * 1.326

  4. Of Pain and Pleasure.
• * 1.327

  5. Of Passion.
• * 1.328

  6. Of several Pulses caused by Passion.
• * 1.329

  7. Of several o∣ther effects caused natu∣rally in the body by pas∣sions.
• * 1.330

  8. Of the Dia∣phragma.
• * 1.331

  9. Concerning pain and plea∣sure caused by the memory of things past.
• * 1.332

  10. How so small bodies, as a∣tomes are, can cause so great motions in the heart.
• * 1.333

  How the vital spirits, sent from thebrain, run to the in∣tended part of the body, without mi∣stake.
• * 1.334

  1. How men are blinded by passion.
• * 1.335

  1. The order and connexion of the subsequent Chapters.
• * 1.336

  2. From whence proceeds the doubting of beasts.
• * 1.337

  3. Concerning the invention of Foxes and other beast.
• * 1.338

  4. Of Foxes that catch hens by lying under their roost and by gazing upon them.
• * 1.339

  5. From whence proceeds the Foxes inven∣tion to rid himself of Flea.
• * 1.340

  6. An explicati∣on of two o∣ther inventi∣ons of Foxes.
• * 1.341

  7. Concerning Montagues argument, to prove that Dogs make syllogisms.
• * 1.342

  8. A declaration how some tricks are per∣form'd by Foxes, which seem to argue discourse.
• * 1.343

  9. Of the Jacca∣trays invention in calling beasts to him∣self.
• * 1.344

  10. Of the Jaccils designe in ser∣vi••g the Lion.
• * 1.345

  11. Of several intentions of Fishes.
• * 1.346

  12: A discovery of divers things done by Hares which seem to argue dis∣course,
• * 1.347

  13. Of a Fox re∣ported to have weigh•• a Goose, before he would ven∣ture with it o∣ver a River; and of fabu∣lous stories in common.
• * 1.348

  14. Of the several Cryings and Tones of Beasts: with a refutation of those Authors who maintain them to have compleat Lan∣guages.
• * 1.349

  1. How Hawks and other creatures are taught to do what they are brought up to.
• * 1.350

  2. Of the Baboon that plaid on a Guittar.
• * 1.351

  3: Of the teach∣ing of Ele∣phants and o∣ther beasts to do divers tricks.
• * 1.352

  4. Of the order∣ly ••ain of actions per∣rformd by 〈◊〉〈◊〉, in breeding their young ones.
• * 1.353

  1. Why beasts are afrad of men.
• * 1.354

  2. How some qualities caus'd at first by chance, in beasts, may pass by gene∣ration to the whole off∣spring.
• * 1.355

  3. How the pa∣rents fantasy oftentimes works strange effects in their issue.
• * 1.356

  4. Of antipa∣thies.
• * 1.357

  5. Of Sympa∣thies.
• * 1.358

  6. That the An∣tipathy of Beasts towards one another may be taken away by assue∣faction.
• * 1.359

  7. Of Longing marks seen in children.
• * 1.360

  Why divers men hate some certain meats, and particu∣larly Cheese,
• * 1.361

  9. Concerning the provi∣dence of Arts, in laying up store for win∣ter.
• * 1.362

  10. Concerning the Foreknow∣ing of Beasts.