Physiologia Epicuro-Gassendo-Charltoniana, or, A fabrick of science natural, upon the hypothesis of atoms founded by Epicurus repaired [by] Petrus Gassendus ; augmented [by] Walter Charleton ...

CHAP. XI. OF THE Motive Vertue, Habit, Gravity, and Levity OF CONCRETIONS.

SECT. I.

THe Third Propriety of the Univer∣sal Matter, Atoms, is Mobility,* 1.1 or Gravity: and from that fountain is it that all Concretions derive their Virtue Motive. For, though our deceptable sense inform us, that the minute Particles of Bodies are fixt in the act of their Coadunation, wedged up together, and as it were fast bound to the peace by recipro∣cal concatenation and revinction: yet, from the D••ssolution of all Compound natures, in process o•• time, caused by the intestine Com∣motions of their Elementary Principles, without the hostility of any Exter∣nal Contraries, may our more judicious Reason well inferr, that Atoms are never totally deprived of that their essential Faculty, Mobility; but are ance••santly agitated thereby even in the centrals of Concretions, the most so••id and compact; some tending one way, others another, in a perpetual 〈◊〉〈◊〉 of Eruption, and when the Major part of them chance to ••ffect 〈…〉〈…〉 the same way of emancipation, then is their united force determi∣mined ••o one part of the Concretion, and motion likewise determined to one region, respecting that Part. That same MOTIVE VIRTUE, there∣••ore, wherewith every Compound Bodie is naturally endowed, must owe ••ts ••rigine to the innate and co-essential Mobility o•• its component parti∣cles▪ being really the same thing with their Gravity, or Impetus: which yet receives its determinate manner and degree from their mutual Combi∣nation. In respect whereof it necessarily comes to pa••s, that when Atoms, mutually adh••ering vnto 〈…〉〈…〉 other, ca••••ot obey the ••mpu••••e

of 〈◊〉〈◊〉 ••••ndency singly, they are not moved with that pernicity, as if each were a•• ••••solute liberty; but impeding and retarding each other in their pro∣gress, ar•• ••••rried with a flower motion, But that more or less slow, accor∣ding to 〈◊〉〈◊〉 rate or proportion of common Resistence: because always some of them are carryed to an opposite, others transversly, others obliquely to a dif••••rent region.

* 1.2An•• 〈◊〉〈◊〉 is it, that because Atoms are at most freedom of range in 〈…〉〈…〉 Concretions▪ every degree of Density and Compactness causin•• 〈◊〉〈◊〉 ••••oportionate degree of Tardity in their spontaneous motions: 〈…〉〈…〉 the Motive Faculty not more generally, than rightly concei∣ved, 〈…〉〈…〉 chiefly in the spiritual, or (as vulgar Philosophy) Aethereal Parts 〈◊〉〈◊〉 Concretions. And, whether the spirits of a thing are princi∣pa•• de••••••mined to move, thither do they not only themselves contend, 〈…〉〈…〉 and speed, but also carry along with them the more 〈…〉〈…〉 less mov••able parts o•• the Concretion; as is superlatively 〈…〉〈…〉 Voluntary motions o•• Animals.

* 1.3W•• 〈◊〉〈◊〉 not here insist upon the Redargution of that Blasphemous and Absur•• 〈◊〉〈◊〉 the forme•• Epi••hit•• always implies the later) dream of 〈…〉〈…〉 Atoms wer•• not only the First Matter, but also the First and 〈…〉〈…〉 of all things▪ and consequently that all Motions, and so all 〈…〉〈…〉 ••niverse and Caused meerly by the inhaerent Mobility of them: be 〈…〉〈…〉 have expresly refuted the same in our Treatise against Atheism, 〈…〉〈…〉 1. artic. ultim). Especially, since it is more opportune for us her•• 〈…〉〈…〉; that insomuch as the motion of all Atoms is supposed 〈…〉〈…〉 D••rect, and most rapid; therefore doth the Deviation, as 〈…〉〈…〉 of Concretions seem to arise from the Deflection, Reper∣cussion 〈…〉〈…〉 Repression of the Atoms composing them. For, the 〈…〉〈…〉 meeting of two Atoms▪ may be in direct lines: so that among 〈…〉〈…〉 singl•• percussion▪ or repercussion overcom••ng the first begun 〈…〉〈…〉 assembly o•• Conventi••n will bear, there may be caused some 〈…〉〈…〉 ••hough more or less slow: and their Occursations may be 〈…〉〈…〉 Oblique angles, and so, by the same reason may ensue a 〈…〉〈…〉 more or less slow, but also more or less Oblique. More∣••ve•• 〈…〉〈…〉 repe••cussion made to oblique angles, there chance to 〈…〉〈…〉 repercussion to angles equally oblique; then must the 〈…〉〈…〉 ••bl••quity multangular, according to the multiplicity 〈…〉〈…〉 the Angles be very frequent and indistant▪ the 〈…〉〈…〉 at least to appearance, to be of an uniform Curvity, and 〈…〉〈…〉 be termed a motion Circular, Elliptical, Helico••••al, 〈…〉〈…〉 a••cording to the condition of its Deflection and Crooked∣••••••••.

* 1.4〈…〉〈…〉 observ••, tha•• every Body, whether Simple or 〈…〉〈…〉 Concretion, fr••m which a Repercussion is made, must 〈…〉〈…〉 b•• move•• the same way, as is the repercust, or not 〈…〉〈…〉 because, otherwise there can be no mutual 〈…〉〈…〉 impingent body rebound from the repercuti∣•••• 〈…〉〈…〉, why ••excepting only the motion 〈…〉〈…〉 of all Concretions doth ever suppose something

that remains Unmoved, or that, in respect of its less motion, is tantamount to a thing Unmoved: because, otherwise there could be no reciprocal Re∣sistence, and so all motion might both begin and repair it self.

Having thus premised these few fundamental Laws of Motion in Ge∣neral,* 1.5 opportunity commands us to descend to the consideration of the FACULTY of Motion: insomuch as it seems not to be any thing distinct from that Motive Force, inhaerent in all Concretions, which we have now both described, and deduced from its immediate origine, the Mobility of Atoms; and that it is well known to all Book-men, to appertain to the se∣cond species of Qualities, according to the method of Aristotle. To which we may add these lessons also, that it comprehends the Third spe∣cies of Qualities, and obtains the First, or Habit, as its proper appendix. Know we, therefore, that the Faculty or Power of Motion doth therefore seem to be one and the same thing with the coessential Mobility, now de∣scribed; because every thing in Nature is judged to have just so much of Efficacy, or Activity, as it hath of Capacity to move either it self, or any o∣ther thing.

And hence is it,* 1.6 that in Nature there is no Faculty (properly) but what is Active; because, though the motions of things be really the same with their Actions: yet must all motion have its beginning only from the Mo∣vent, or Agent. Nor can it avail to the contrary, that all Philosophers have allowed a Passive Faculty to be inhaerent in all Concretions; since, in the strict dialect of truth, that Passiveness is no other than a certain Impotency of Resistence, or the Privation of an Active Power, in defect whereof the subject is compelled to obey the Energy of another. If you suppose an ob∣scure Contradiction in this our Assertion, and accordingly Object; that therefore there must be a Faculty of Resistence, in some proportion, and that that Resistence is Passive: we are provided of a satisfactory salvo, which is, that though the Active Virtue, which is in the Resistent, doth sometimes scarce discover it self, yet is it manifest, that there are very many things, which make resistence only by motion, which no man can deny to be an Active Faculty; as when we rowe against wind and tide, or strive with a Bowe in the drawing of it, for all these evidently oppose our force by contrary mo∣ton. And, as for other things, which seem to quiesce, and yet make some resistence; such we may conceive to make that resistence by a kinde of motion, which Physicians denominate a Tonick motion; like that of the Eye of an Animal, when by the Contraction of all its muscles at once it is held in one fixt position. Thus not only the whole Globe of the Earth, but all its parts are held unmoved, and first by mutual cohaerence, and resist motions as they are parts of the whole: and thus also may all Concretions be conceived to be made Immote, not that the Principles of which they consist▪ are not in perpetual inquietude and motion; but, because their par∣••••cles reciprocally wedge and implicate each other, and while some impede ••nd ••ppose the motions of others, they all conspire to the Consistence of ••he whole. However the more Learned and Judicious shall further dispute ••his paradoxical Argument; yet dare we determine the Common Noti∣••n of a Faculty to be this, that there is inherent in every thing a Prin∣••••ple of Moving itself, or Acting, if not Primary ••which the schools terme the Forme) yet Secondary at least, or profluent from the

Forme, being as it were the immediate Instrument thereof.

* 1.7And here we cannot conceal our wonder, that the Peripatetick hath not for so many ages together discovered himself to be intangled in a mani∣fest Contradiction; while on one part He affirms, that there are certain Faculties flowing â tota substantia, from the whole substance of a thing, as if they were derived from the matter of Concretions: and on the other, concludes, as indisputable, that the Matter is absolutely devoid of all Activity, as if it were not certain, that the Faculties frequently perish, when yet not the whole and intire substance of the thing perisheth, but only the spiritual, or more tenuious parts thereof.

* 1.8Now, what more praegnant Argument than this can the most circum∣spect desire, in order to their Conviction, that the Faculties of an Ani∣mal (we exclude the Rational Faculty of man, from the sphere of our assertion) ar•• Identical with the Spirits of it, i. e. the most subtile, most free, and most moveable or active part of its materials? For, though the spirits are by vulgar Philosophers conceived to be only the Primary Organ, or immediate Instrument, which the Faculty residing in one part, occasionally transmits into another: yet, to those Worthies, who have with impartial and profound scrutiny searched into the mystery, hath it appeared more consentaneous, that the spirits are of the same nature with the Faculty, and not only movent, but Instrument; nor can it stand with right reason to admit more than this, that as water in the streams is all one specifically with that in the fountain, so is the Fa∣culty, keeping its court or chief residence in one part of the bo∣dy, as it were the Fountain, or Original, from whence to all other parts, inservient to the same function, the diffusion of spirits is made, in certain exile rivolets, or (what more neerly attains the abstrusity) Rayes, like those emitted from the Sun, or other fountain of light. And, what we here say, of the Faculties of Animals, holds equal truth, also concerning those of Inanimate Concretions; allowing a difference of proportion.

* 1.9But here ariseth a considerble Difficulty, that at first view seems to threaten our Paradox with total ruine; and this it is: if the Fa∣culties of Concretions be not distinct in essence from their spirits, or most agile particles; how then can there be so many various Faculties coexistent in one and the same concretion, as are dayly observed; for in an Apple, for example, there is one Faculty of affecting the sight, another of affecting the taste, a third affecting the smell. Concerning this, therefore, we give you this solution, that the co∣existence of various Faculties in one Concretion, doth depend upon (1) the variety of multiforme particles, of which the whole Con∣cretion doth consist, (2) the variety of particles and special con∣texture of its divers parts, (3) the variety of External Faculties, to which it happens that they are applied. To keep to our former Example, in an Apple, tis manifest, there are some particles, in which consisteth its faculty of affecting the smell, others in which consisteth its faculty of affecting the Tast; for, the Experiments of Chymistry demonstrate, that these different particles may be so sequestred each from other, as that the tast may be conserved, when the smell is lost,

and the smell conserved, when the taste is abolished. And in an Animal it is no less evident, that the organ of one sense hath one peculiar kind of contexture, the organ of another sense another: and finally, that when we shall referr the Faculties of Odour and Sapour, which are in an Apple, to the Faculties of smelling and tasting in Animals; they become subject to a further discrimination. Since the same particles, which move the smelling, shall create a sweet and grateful odour, in respect of one Animal, and an offensive or stinking, in respect of another: and in like man∣ner, those particles, which affect the Taste, shall yeild a most grateful and desireable Sapour, to one Animal, and as odious and detestable a one to another. Ought we, therefore, to account that Faculty of an Odour, which is in an Apple, either Single, or Multiplex? If we would speak strictly, it is Single Absolutely: Respectively, Multiplex. And thus, in∣deed, may we affirm, that in the General, or absolutely, an Apple is Odo∣rous and Sapid: but Comparatively and in Special, that it is fragrant, or foetid; sweet or bitter.

As for that Appendix of a Faculty, which not only Philosophers,* 1.10 but the People also name a HABIT; Experience daily teacheth, that there are some Faculties, (in Animals especially) which by only frequency of acting grow more prompt and fit to act: and upon consequence, that that Hability or promptness for action, is nothing but a Facility of doing, or repeating that action, which the same Faculty, by the same instruments, hath frequently done before.

And, as to the Reason of this Facility;* 1.11 though it arise in some measure from the Power or Faculty it self, or the Spirits, as being accustomed to one certain motion: yet doth it chiefly depend upon the Disposition of the Organs, or instruments which the Faculty makes use of in the performance of its proper action. For, because the Organ is alwayes a Dissimilar or Compound Body, consisting of some parts that are crass and rigid; we are to conceive it to be at first somewhat stubborn, and not easily flexible to such various motions, as the Faculty requires to its seve∣ral operations: and therefore, as when we would have a Wand to be every way easily flexible, we are gently and frequently to bend it, that so the tenour of its fibres running longwise through it, may be here and there and every where made more lax, without any sensible divulsion; so if we desire to have our hands expedite for the performance of all those difficult motions that are necessary to the playing of a Lesson on the Lute, we must by degrees master that rigidity or clumsiness in the Nerves, Tendons, Mu∣scles and joints of our fingers, yea in the very skin and all other parts of our hands. Thus also Infants, while they stammer, and strive again and again to pronounce a word clearly and distinctly, do no more than by degrees master the stiffness and sluggishness of their tongues and other vocal organs, and so make them more flexible and voluble: and when by assuefaction they have made them easily flexible to all the motions required to the formation of that idiome, then at length come they to speak it plainly and perfectly. The same is also true, concerning the Brain, and those Organical parts therein, that are inservient to the act of Imagination, and by the imagination to the act of Discourse. For, though the Mind, when divorced from the the body, can operate most readily, and knows no difficulty or impediment in the act of Intellection; as being Immaterial, and so wanting no organs

for the exercise of its reasoning Faculty: yet nevertheless, while it is adliged to the body and its material instruments, doth it remain subject to some im∣pediment in the execution of its functions; and because that impediment consisteth only in the less aptitude or inconformity of its proper organs, therefore the way to remove that impediment, is only by Assuefaction of it to study and ratiocination. And from this Assuefaction may the Mind be affirmed to acquire a certain Habit or Promptitude to perform its proper Actions; insomuch as by reason of that Habit, it operates more freely and expeditely: but, yet, in stricter Logick, that Habit ariseth chiefly to its Organs; as may be inferred only from hence, that the Organs are capable of increment and decrement, and to increase and decrease, is competent only to a thing that consisteth of parts; such as is the Organ, not the Mind.

* 1.12Nor is the acquisition of a Habit by assuefaction proper only to Man, but in common also to all Living Creatures, such especially as are used to the hand and government of Man, as Horses, Doggs, Hawks, and all pra∣ting and singing Birds. And where we affirmed, that some Faculties are capable of advancement to perfection by Habit; we intended, that there are other Faculties which are incapable thereof, as chiefly the Natural Facul∣ties in Animals, and such as are not subject to the regiment of the Will: though still we acknowledge that some of these there are, which upon change of temperament in their respective Organs, may acquire such a cer∣tain Habit, as may oppose the original inclination; and of this sort the principal is the Nutrient Faculty, which may be accustomed even to Poison. Lastly, when we, said Chiefly in Animals; we were unwilling totally to ex∣clude Plants; because they also seem (at least Analogically) to acquire a kind of Habit: as is evident from their constant retaining of any po∣sture or incurvation, which the hand of the Gardiner hath imposed upon them, while they were tender and flexible; as also that they may by de∣grees be accustomed to forein soils, and (what is more admirable) if in their transplantation those parts of them, which at first respected the South or East, be converted to the North or West, they seldome thrive, never attain their due procerity. Nay, if the Experiments of some Physitians be true, Minerals also may be admitted to attain a Habit by assuefaction; For Bap∣tista van Helmont, (in lib. de Magnetica Vulnerum curatione, & lib. de Pe∣stis tumulo) reports that He hath found a Saphire become so much the more efficacious an Attractive of the pestilential Venome from the Vitals, by how much the more frequently it hath been circumduced about Carbun∣cles or Plague Sores; as if Custome multiplied its Amuletary Virtue and taught it a more speedy way of conquest.

SECT. II.

AMong all Qualities of Concretions,* 1.13 that deduce themselves from the Mobility of Atoms, the most eminent is GRAVITY, or the motion of perpendicular Descent from Weight. Which, though most ob∣vious to the observation of Sense, hath much of obscurity in its Nature; leading the Reason of Man into various and perplext Conceptions concerning its Causes: nor hath the judgment of any been yet so fortunate as to light upon a Demonstrative Theory concerning it, or fix upon such a determination as doth not lye open to the ob∣jection of some considerable Difficulty. So that it may well seem Ambition great enough for us, onely with due uprightness to ex∣amine the Verisimility of each opinion, touching the Formal Rea∣son, or Essence of Gravity: that so we may direct younger Cu∣riosities, in which they may, for the praesent, most safely ac∣quiesce.

Epicurus, indeed, well desumes the Gravity of all Concretions,* 1.14 immediately from the Gravity of Simple Bodies, or Atoms: in∣somuch as all things are found to have so much more of Weight, as they have of Atoms, or Matter, that composeth them; and è contra. Which reason the exact Ioh. Bapt. Balianus, a Nobleman and Senatour of Genoa, seriously perpending; sets it down as a firm ground, Gravitatem se habere ut Agens, Materiam vero, seu Materiale corpus, ut Passum; & proinde gravia moveri juxta pro∣portionem gravitatis ad materiam: & ubi sine impedimento naturalitèr perpendiculari motu ferantur, moveri aequalitèr; quia ubi plus est Gravitatis, plus ibi paritèr sit Materiae, seu Materialis quantitatis; (de motu Gravium Solidorum & Liquidorum, lib. 1. cap. 1.). But, this being too General, and concerning rather the Cause of Comparative, than Absolute Gravity; leaves our Curiosity to a stricter search.

The Grand Dictator of the Schools, Aristotle,* 1.15 taking it for granted [Unumquodque sensilium ita in suum locum ferri, ut ad spe∣ciem] that every corporeal Nature is by native tendency carried to its proper place, as to its particular Species; confidently inferrs this doctrine: that Gravity and Levity are Qualities essentially inexistent in Concretions (4. de Caelo, cap. 3.) and passionately reprehend∣ing Democritus and Leucippus, for affirming that there is no such thing in Nature, as Absolute Gravity, or Absolute Levity; concludes, that in Nature is something absolutely Heavy, which is Earth, and some∣thing Absolutely Light, which is Fire; (de Caelo, lib. 4. cap. 4.) But, neither of these Positions are more than Petitionary; and so not worthy our assent: as the Context of our subsequent Discourse doth sufficiently convince.

* 1.16The Third opinion worthy our memory, is that of Copernicus, who considering, that all Heavy Bodies, either projected Upwards by external violence, or dropt down from some eminent place, are observed to fall perpendicularly down upon the same part of the Earth, from which they were elevated, or at which they are aimed, and so that the Earth might be thence argued not to have any such Diurnal Ver∣tigo, as His Systeme ascribes unto it, insomuch as then it could not but withdraw it self from Bodies falling down in direct lines, and re∣ceive them at their fall not in the same place, but some other more Westernly: we say, considering this, Copernicus determined Gravi∣ty to be, not any Internal Principle of tendency toward the middle, or Centre of the Universe; but an innate propension in the parts of the Earth, separated from it, to reduce themselves in direct lines, or the nearest way, to their Whole, that so they may be conserved together with it, and dispose themselves into the most convenient, i. e. a sphaerical figure, about the centre thereof. His words are these; Equi∣dem existimo, Gravitatem non aliud esse, quàm Appetentiam quandam na∣turalem, partibus inditam à Divina Providentia Opificis Universorum; ut in unitatem integritatemque suam sese conferant, in formam ••lobi coeuntes: quam Affectionem credibile est etiam Soli & Lunae, caeterisque Errantibus fulgoribus inesse; ut ejus efficacia in ea, qu•• se repraesentant, rotunditate permaneant. (lib. 1. cap. 9.). So that according to this Copernican Assumption, if any part of the Sun, Moon, or other Coe∣lestial Orb were divelled from them; it would, by the impulse of this natural tendency, soon return again in direct lines to its proper Orb, not to the Centre of the Universe. Which as Kepler (in Epitom. Astro∣nom. pag. 9••.) well advertiseth, is but a Point, i. e. Nothing, and destitute of all Appertibility; and therefore ought not to be accounted the Term of tendency to all Heavy Bodies, but rather the Terrestrial Globe together with its proper Centre, yet not as a Centre, but as the Middle of its Whole, to which its Parts are carried by Cog∣nation.

But, this opinion hath as weak a claim to our Assent, as either, of the former; as well because it cannot consist with the Encrease of Velocity in all Bodies descending perpendicularly, by how much nearer they approach the Earth, unless it can be demonstrated, that this encrease of Velocity in each degree of descent, ariseth only from the Encrease of Appetency of Union with the whole (which neither Copernicus himself, nor any other for Him, hath yet dared to assent): as in consideration of many other Defects, and some Ab∣surdities, which, that wonder of the Mathematicks, Ricciolus, hath demonstratively convicted it of (in Almegisti novi parte posteriori, lib. 9. sect. 4. cap. 16. de Systemate terrae motae.). Who, had He but as solidly determined all the Difficulties concerning the immedi∣ate Cause of this Affection in Bodies, called Gravity; as He hath re∣futed the Copernican Thesis of an Innate Appetency in the parts of the Earth to reunite themselves to the Whole: doubtless He had much encreased the obligations and gratitude of his Readers. But, making it his principal design to propugn the Physiology and Astro∣nomy of the Ancients, especially such Tenents as are admitted by the Schools, and allowed of by the Doctors of Rome, as most concordant to the

litteral sense of Sacred Writ: He waved that Province, seeming to adhaere to the common Doctrine of the Stagirite, formerly recited, and only occa∣sionally to defend it.

Lastly, there are Others (among whom Kepler and Gassendus de∣serve the richest Minervals) who, neither admitting with Aristotle,* 1.17 that Gravity is any Quality essentially inhaerent in Concretions; nor, with Copernicus, that it is an Appetency of Union, implanted originally in the parts of the Earth, by vertue whereof they carry themselves towards the Middle of the Terrestrial Globe: define it to be an Im∣prest Motion, Caused immediately by a certain Magnetick Attraction of the Earth.

And this opinion seems to carry the greatest weight of Reason; as may soon be manifest to any competent and equitable judgment, that shall exactly perpend the solid Arguments alledged by its Assertors: which for greater decorum, we shall now twist together into one conti∣nued thread, that so our Reader may wind them into one bottome, and then put them together into the ballance.

Insomuch as frequent and most accurate observation demonstrates,* 1.18 that the Motion of a Body downward doth encrease in the same propor∣tion of Velocity, that the motion of the same Body, violently pro∣jected upward, doth decrease; therefore is it reasonable, nay necessa∣ry for us to conceive, that there are Two distinct External Principles, which mutually contend about the same subject, and execute their contrary forces upon the same Moveable. Now, of these two An∣tagonistical Forces, the one is Evident; the other obscure, and the argument of our instant Disquisition. Manifest it is, when a stone is thrown upward from the surface of the Earth into the Aer, that the External Principle of its motion Upward, is the Hand of Him, who projected it: But somewhat obscure, what is the External Princi∣ple of its motion Downward, when it again returns to the Earth. Ne∣vertheless, this obscurity doth not imply a Nullity, i. e. it is high temerity to conclude that there is no External Cause of the stones Descent, because that External Cause is not equally manifest with that of its Ascent: unless any dare to affirm, that because He can perceive, when Iron is attracted to a Loadstone, no Externall Cause of that Attraction, therefore there can be none at all. Many, indeed, are the wayes, by which an External Cause may move a Body: and yet they all fall under the comprehension of only two Cardinal wayes, and those are Impulsion, and Attraction.

This praeconsidered, it followes,* 1.19 that we cast about to finde some Cause, or Impellent, or Attrahent (or rather two Causes, one Impellent, the other Attrahent, operating together) to which we may impute the perpendicular motion of Bodies Descending. The Impellent Cause (if any such there be) of the perpendicular mo∣tion of a stone Descending, can be no other but the Aer, from above incumbent upon, and pressing it downward: because of any other External Cause of that effect, no argument can be given. For, should you suppose a sphere of Fire, or some other

or some other Aethereal Substance, to be immediately above the convex Ext••eme of the sphere of Aer; which closely and with some kind of pressure invironing the Aer, might compel all its parts to flow together toward the Terraqueous Globe: yet could that super-ae∣real sphere, bounded and urged by the circumvolutions of the Coele∣stial Orbs, do no more, than cause the Aer, being it self prest down∣ward, to bear down upon the stone, and so depress it; and so the Aer must still be at least the Proxime Cause impelling the stone downward. Moreover, that the Aer alone may be the Impellent Cause of the stones perpendicular Decidence from on high, even Aristotle Himself seems to concede▪ insomuch as He is positive in his judgment, that when a Heavy body projected upward is abandoned by its Motor, it is after∣ward moved only by the Aer, whi••h being moved by the Projicient, moves the next conterm••••ous Aer, by which again the next neighbouring Aer is like••••se moved, an•• so successively forward untill the force of the Imprest motion gradually decaying, the whole communicated motion ceaseth, and a quiet succeeds. But, betause Aristo le could not tell, what Cause that is▪ which in every degree of the stones ascent opposing, at length who•••••• overcomes the imprest force; un••ess it should be the occurrent superiour Aer, which continually resisteth the inferior aer, whereby the projected stone is promoted in its ascent: may not we safely enough conclude, that the Aer from above incumbent upon the projected stone, may by the same force depress it Downward, wherewith it first resisted the motion of it Upward? Doubtless, what force•• soever the Hand of a man, who projects a stone up∣ward into the Aer, doth impress upon it, and the contiguous Aer; yet still is 〈◊〉〈◊〉 the superiour Aer, that both continually resisteth the tendency 〈◊〉〈◊〉 the stone upward, and at its several degrees of ascent re••racteth 〈◊〉〈◊〉 force thereupon imprest by the hand of the Projici∣ent, unt•••••• having totally overmastered the same, it so encreaseth its conqu••••••g Depellent force, as that in the last degree of the stones De••endent motion, the Depressive force of the Aer is be∣come as great, as was the Elevating force of the Hand, in the be∣ginning of 〈◊〉〈◊〉 Ascendent motion. Suppose we, that a Diver should from the bottome of the Sea throw a stone directly upward, with the same ••••••ce, as from the surface of the Earth up into the Aer; and then ••••mand, Why the stone doth not ascend to the same height in the Water, as in the Aer. Is it not, think you, be∣cause the 〈◊〉〈◊〉 doth more resist, and refract the Imprest force, and so soo•••••• overcome it, and then begins to impress its own con-contrary Depressing Force thereupon, never discontinuing that im∣pression, 〈◊〉〈◊〉 it hath reduced the stone to the bottom of the Sea, from whe•••••• it was projected? The Difference, therefore, betwixt the Resistence of the Imprest force, by the Water, and that of the Aer ••••••sisteth only in Degrees, or more and less. And, though the 〈◊〉〈◊〉 of the Aer may be thought very inconsiderable in com∣parison o•• 〈◊〉〈◊〉 great Violence imprest upon a Cannon Bullet, shot upw••rd 〈…〉〈…〉 the Aer: yet be pleased to consider, that it holds some 〈◊〉〈◊〉 proportion, with the Renitency o•• the Water. Which 〈…〉〈…〉 that we may understand, compare we not only the very 〈◊〉〈◊〉 Ascent of a stone, thrown upward from the bottome

of the Sea, to the large ascent of the same stone, with equal force, from the Earth, thrown up into the Aer; but also the almost insensible progress of a Bullet shot from a Cannon transversly through Water, with that vast progress it is commonly observed to make through the Aer: and we shall soon be convinced, that as the Great Resistence of the Water is the Cause, why the Stone, or Bullet makes so small a pro∣gress therein; so is the small Resistence of the Aer the Cause why they both pervade so great a space therein. And thus is it Demonstrable, that the Resistence of the superior Aer, is the External Agent, which constantly resisteth, by degrees refracteth, and at length wholly overcomes the imprest Force, whereby Heavy Bodies are violently elevated up into the Aer.

The Difficulty remaining, therefore,* 1.20 doth only concern the Impel∣lent Cause of their Fall Down again; or, whether the Aer, besides the force of Resistence, hath also any Depulsive Faculty, which be∣ing imprest upon a stone, bullet, or other ponderous body, at the top, or highest point of its mountee, serveth to turn the same Downward, and afterward to continue its perpendicular descent, till it arrive at and quiesce on the Earth. Which, indeed, seems well worthy our Doubt, because it is observable, that Walls, Pavements, and the like solid and immote Bodies, though they strongly resist the motion of bodies impinged against them; doe not yet impress any Contrary motion thereupon: the Rebound of a Ball or Bullet from a Wall, being the effect meerly of the same force imprest upon it by the Racket, or Gun-powder fired, which first moved it; as is evident even from hence, that the Resilition of them to greater or less di∣stance, is according to the more or less of the Force imprest upon them. Which those Gunners well understand, who experiment the strength of their Powder, by the greatness of the bullets rebound from a Wall.

And to solve this Difficulty, we must distinguish betwixt Bodies, that are devoid of Motion, and which being distracted, have no fa∣culty of Restitution, whereby to recollect their dissociated particles, and so repair themselves; of which sort are Walls, Pavements, &c: and such bodies that are actually in motion, and which by reason of a natural Elater, or Spring of Restitution, easily and speedily redinte∣grate themselves, and restore their severed parts to the same contexture and tenour, which they held before their violent distraction; to which classis the Aer doth principally belong. Now, concerning the First sort, what we object of the non-impression of any Contrary motion upon Bo∣dies impinged against them, is most certainly true: but not concerning the Latter. For, the Arm of a Tree, being inflected, doth not only resist the inflecting force, but with such a spring return to its natural site, as serveth to impel any body of competent weight, that shall op∣pose its recurse, to great distance; as in the discharge of an Arrow from a Bow. Thus also the Aer, though otherwise unmoved, may be so distracted by a Body violently pervading it; as that the parts thereof, urged by their own native Confluxibility (the Cause of all Elaterical or Restorative Motion) must soon return to their natural te∣nour and site, and not without a certain violence, and so replenish the

place form••rly possest, but now deserted by the body, that distracted them. Th•••• there is so powerful a Restorasive faculty in the Aer, as we here ••ssume; innumerable are the Experiments, those especially by Philosophers usually alledged against a Vacuum Coacervate, which attest. However, that you may the less doubt of its having some, and a consid••rable force of propelling bodies notwithstanding it be Fluid in so high a degree: be pleased only to reflect your thoughts upon the great ••orce of Winds; which tear up the deepest and firmest root∣ed Cedars ••••om the ground, demolish mighty Castles, overset the proudest C••••racts, and rowle the whole Ocean up and down from shoar to sho••••. Consider the incredible violence, wherewith a Bullet is discharged from a Wind-Gun, through a firm plank of two or three inches thickness. Consider that no effect is more admirable, than that a very small quantity of Flame should, with such prodigious im∣petuosity▪ drive a Bullet, so dense and ponderous, from a Cannon, through th•• Gates of a City, and at very great distance: and yet the Flame 〈◊〉〈◊〉 the Gunpowder is not less, but more Fluid than Aer. Who, without the certificate of Experience, could believe, that meerly by the force of so little Flame (a substance the most Fluid of 〈◊〉〈◊〉, that we know) not onely so weighty a Bullet should be driven with such pernicity forward through the aer to the di∣stance of many furlongs; but also that so vast a weight, as a Can∣non and its Carriage bear, should at the same time be thereby driven backwards, or made to recoyle? What therefore will you say, if this could not come to pass, without the concurrence of the Aer? For▪ it seems to be effected, when the Flame, at the instant of its Creation, seeking to possess a more ample room, or space, doth conv•••• its impetus, or violence as well upon the breech, or hinder part 〈◊〉〈◊〉 the Canon, as upon the bullet lying before it in the bore or 〈◊〉〈◊〉; which discharged through the concave, is closely prest upon 〈◊〉〈◊〉 the pursuing flame: so that the flame immediately pe∣rishing▪ 〈◊〉〈◊〉 leaving a void space, the Aer from the front or adverse part insta•••• rusheth into the bore, and that with such impetuous pernicity, 〈◊〉〈◊〉 it forceth the Cannon to give back, and yeilds a Fragor, or Report▪ as loud as Thunder; nay, by the Commotion of the vicine Aer 〈◊〉〈◊〉 ••••akes even the largest structures, and shatters Glass-windows 〈◊〉〈◊〉 in the sphere of its violence. And all meerly from the 〈◊〉〈◊〉 Motion of the Aer, restoring its distracted parts to their n••••ural tenour, or Laxity: so that you may be satisfied of its Capacity not only to resist the Ascent of a stone thrown upward; but also of Depelling it downward, by an imprest Mo∣tion.* 1.21

Notwithstanding our conquest of the main body of this Diffi∣culty, abou•• the Restorative Motion of the Aer, we are yet to encounter 〈◊〉〈◊〉 formidable Reserve, which consists of these Scruples. When a 〈◊〉〈◊〉 is thrown upward, doth not the Aer in each de∣gree of 〈◊〉〈◊〉 ascent, suffer a Distraction of its parts; and so is compelled 〈◊〉〈◊〉 a Periosis, or circular motion, to succeed into the place left below by the stone? Doth it not therefore impress ra∣ther an 〈◊〉〈◊〉, than a Depulsive Force thereupon, and so promote

the force imprest upon it by the hand of Him, who projected it? And must it not thence follow, that the first imprest motion is so far from being decreased by the supposed Renitency of the superior Aer, that it is rather increased and promoted by the Circulation thereof: and upon conse∣quence, that the stone is carried upward twice as swiftly, as it falls down∣ward, since it is impelled upward by two forces, but falls down again only by a single force? True it is, that while a stone is falling down, the distra∣cted aer beneath seems to circulate into the place above deserted thereby: but, in case a stone be held up on high in the Aer by a mans hand, or other support, and that support be withdrawn so gently, as to cause no considera∣ble commotion in the Aer; in this case there seems to be no reason, why the Aer should flow from above down upon it in the first moment of its de∣lapse. Besides, when a stone projected upward, hath attained to the highest point of its ascent, at which there seems to be a short pause, or re∣spite from motion, caused by the aequilibration of the two Contrary Forces, the Movent and Resistent: why doth not the stone absolutely quiesce in that place, there being in the Aer no Cause, which should rather Depel it ••ownward, then elevate it upward?

These considerations, we ingenuously confess, are potent, and put us to the exigent of exploring some other External Principle, beside the motion of Restitution in the Aer; such as may Begin the Downward motion of the stone, when gently dropt off from some convenient supporter, or when it is at the zenith or highest point of its ascent, and and at the term of its Aequilibration overcome the Resistence of the subjacent Aer, that so it may not only yeeld to the stone in the first moment of its Descent; but by successive Circulations afterward promote and gradually accelerate its mo∣tion once begun. Depellent Cause there can be none; and so there must be some Attrahent, to begin the stones praecipitation: and that can be no other, but a Certain peculiar Virtue of the whole Terrestrial Globe, whereby it doth not onely retain all its Parts, while they are contigu∣ous or united to it, but also retract them to it self, when by any violence they have been avulsed and separated. And this Virtue may therefore be properly enough called Magnetique.

In Nature, nothing is whole and entire,* 1.22 in which there is not radi∣cally implanted a certain self-Conservatory Power, whereby it may both contain its several parts in cohaerence to it self, and in some mea∣sure resist the separation or distraction of them; as all Philosophers, upon the conviction of infinite Experiences, decree: and if so, it were a very par••ial A••s••rdity to bereave the Terraqueous Globe, being a Body whole and entire, of the like conservatory Faculty. And hence comes it, that if any Parts of the Earth be violently avelled from it; by this Conservatory, (which must be Attractive) Virtue, it in some measure resisteth their avulsion, and after the cessation of the Avelling violence, retracteth them again; and this by insensible Emanations, or subtile threads, deradiated continually from its whole body, and hookt or fastned to them: as a man retracts a Bird flown from his hand, by a line or thread tyed to its feet.

* 1.23By the Parts of the Terrestrial Globe we intend not only the parts of Earth and Water (the liquid part of the Earth, and as Blood in an Ani∣mal) nor only all stones, Metalls, Minerals, Plants, Animals, and whatever Bodies derive their principles from them, such as Rain, Dew, Snow, Hail, and all Meteors, Vapours, and Exhalations; nor only the Aer, wherewith the globe of Earth is circumvested, as a Quince or Malacotone is periwiggd about with a lanuginous or Hoary substance, (because, if we abstract from the surface of the Earth all vapours, expi∣rations, fumes, and emanations of subtle bodies from water and other sub∣stances, which ascend, descend, and everywhere float up and down in the Atmosphere, nothing can remain about the same, but an Empty space,) but also Fire it self, which hath its original likewise from terre∣strial matter, as wood, oyl, fat, sulphur, and other unctuous and com∣bustible substance. Because all these are Bodies, which as Parts of it self the Earth containeth and holds together; not permitting any of them to be avelled from its orbe, but by some force that exceeds its retentive power: and when that avellent force ceaseth, it suddainly retracts them a∣gain to it self. And, insomuch as two bodies cannot coexist in one and the same place at once; therefore comes it to pass, that many bo∣die•• being at once retracted toward the Earth, the more terrene are brought neerer to the surface thereof, extruding and so succeeding in to the rooms of the less terrene: whence the neerer adduced and Ex∣truding Bodies are accounted Heavy, and the Extruded and farther re∣moved, are accounted Light.

* 1.24Secondly, that the Earth is naturally endowed with a certain Magne∣tical Virtue, by which perpetually diffused in round, it containeth its parts in cohaerence, and reduceth those, which are separated from it self; af∣ter the same manner, as a Loadstone holds its own parts together, and attracts Iron (which is also a Magnetique Production, as Gilbert (de mag∣net. lib. 1. cap. 16.) from the observation of Miners, and other solid rea∣sons, hath confirmed) to it self, and retracts it after divulsion or separa∣tion: we say, all this may be argued from hence, that the whole Globe of the Earth seems to be nothing but one Grand Magnet.

(1) Because a Loadstone, tornated into a sphere, is (more than Ana∣logically only) a Little Earth: being therefore nicknamed by Gilbert (de magnet. lib. 1. cap. 3▪) 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, Terella; insomuch as the one, so also hath the other its Poles, its Axis, Aequator, Meridian, Para∣lels.

(2) Excepting only some parts, which have suffered an alteration and di∣minution, if not a total amission of Virtue, in the Exteriors of the Earth; all parts thereof discover some magnetick impraegnation: some more vigorous and manifest, as the Loadstone, and Iron; others more languid and obscure, as White Clay, Bricks, &c.

Whereupon Gilbert erects his conjectural judgement, that the whole Globe Terrestrial is composed of two General parts, the shell, and Ker∣nel: the Shell not extending it self many hundred fathoms deep (which is very small comparatively to the vastness of its Diametre, amounting to 6872 miles, Italian measure) and all the rest, or Kernel, being

one continued Loadstone subst••ntially. (3.) The Loadstone always con∣verteth those parts of it self toward the Poles, which respected them in its mineral bed, or while it remaind united to the Earth. All which are no contemptible Arguments of our Thesis, that the whole Earth is endowed with a magnetique Faculty, in order to the Conser∣vation of its Integrity.

Whether the Entrals of our Common Mother, and Nurse,* 1.25 the Earth, be, as Gilbert would persuade us, one Great Loadstone substanti∣ally; is not more impossible to prove, than impertinent to our prae∣sent scope▪ it being sufficient to the verisimility of our assigned Cause of the perpendicular motion of Terrene Bodies, to conceive the Globe of the Earth to be a Loadstone only Analogically, i. e. that as the Loadstone ••••th perpetually emit certain invisible streams of exile parti∣cles, or Rays of subtle bodies, whereby to allect magnetical bodies to an union with it self; so likewise doth the Earth uncessantly emit certa••n invisible streams, or Rays of subtile bodies, wherewith to attract all its ••••stracted and divorced Parts back again to an Union with it self, and there closely to detain them. And justifiable it is for us to affirm, that f••••m the Terraqueous Orbe there is a continual Efflux, not only of Va∣pou••s, Exhalations, and such small bodies, of which all our Meteors are composed▪ nor only of such, as the general mass of Aer doth consist of: but also of othe•• particles far more exile and insensible, nor less subtile than tho••e, which deradiated from the Loadstone, in a moment permeate the most solid Marble, without the least diminution of their Virtue. Be∣cause, as the Attractive Virtue of the Loadstone is sufficiently demonstra∣ted by the Effect of it, the actual Attraction of Iron unto it: so is it law∣ful for us to conclude the Earth to be endowed with an Attractive Virtue also, meerly from the sensible Effect of that Vertue, the actual Attra∣ction of stones, and all other bodies to it self; especially since no o∣ther Conception of the Nature of that Affection, which the world calls Gravity, can be brought to a cleer consistence with that notable Apparence, the gradual Encrease of Velocity in each degree of a bo∣dies perpendicular fall.

Besides, the Analogy may be farther deduced from hence;* 1.26 that as the Virtue of the Loadstone is diffused in round, or spheri∣cally, and upon consequence, its Effluvia, or Rays are so much the more rare, by how much the farther they are transmitted from their source or original; and so being less united, become less vigorous in their attraction, and at large distance, i. e. such as exceeds the sphere of their Energy, are languid and of no force at all: so doth the Terrestrial Globe diffuse its Attractive Virtue in round, and upon consequence, its Effluvia, or Rays become so much the more rare or dispersed, by how much farther they are transmitted from their fountain; and so being less united, cannot attract a stone or other terrene body at excessive d••stance, such as the Supralunary and Ultramundane spaces. Which that we may assert with more per∣spicuity, let us suppose a stone to be placed in those Imaginary spaces which are the outside of the World, and in which God, had He so pleased,

might have created more worlds; and then examine, whether it be more reasonable, that that stone should rather move toward this our Earth, than remain absolutely immote in that part of the Ultramandan spaces wherein we suppose it posited. If you conceive, that it would tend toward the Earth; imagine not only the Earth, but also the whole machine of the world to be Annihilated, and that all those vast spaces, which the Universe now possesseth, were as absolutely Inane, as they were before the Creation: and then at least, because there could be no Centre, and all spaces must be alike indifferent, you will admit, that the stone would remain fixt in the same place, as having no Affec∣ctation, or Tendency to this part of those spaces, which the Earth now possesseth. Imagine the World to be then again restored, and the Earth to be resituate in the place as before its adnihilation; and then can you conceive that the stone would spontaneously tend toward it? If you suppose the Affirmative; you will be reduced to inextri∣cable difficulties, not to grant the Earth to affect the stone, and up∣on consequence, to transmit to it some certain Virtue, consisting in the substantial Emanations, not any simple and immaterial Quality, whereby to give it notice of its being restored to its pristine situation and condition. For, how otherwise can you suppose the stone should take cognizance of, and be moved toward the Earth. Now, this be∣ing so, what can follow, but that stones, and all other Bodies account∣ed Heavy, must tend toward the Earth, only because they are Attra∣cted to it, by rays or streams of Corporeal Emanations from it to them transmitted? Go to then, let us farther imagine, that some certain space in the Atmosphere, were, by Power supernatural, made so Empty, as that nothing could arrive thereat either from the Earth, or any other Orbe: can you then conceive, that a stone placed in that Inanity, would have any Tendency toward the Earth, or Affectation to be united to its Centre? Doubtless, no more, than if it were posited in the Extra∣mundan spaces▪ because, having nothing of Communication therewith, or any other part of the Universe, the case would be all one with the stone, as if there were no Earth, no World, no Centre. Wherefore, since we observe a stone from the greatest heighth, to which any natural force can elevate the same, to tend in a direct or perpendicular line to the Earth; what can be more rational than for us to conceive, that the Cause of that Tendency in the stone is onely this, that it hath some communication with the Earth; and that not by any naked or Immaterial Quality, but some certain Corporeal, though most subtile Emanations from the Earth? E∣specially, since the Aer incumbent upon the stone, is not sufficient to Be∣gin its motion of Descent.

* 1.27If you shall yet withhold your Assent from this Opinion, which we have thus long endeavoured to defend; we conjecture the Remora to be chiefly this: that it seems improbable, so great a Bulk, as that of a very large stone, and that 〈◊〉〈◊〉 such pernicity, should be attracted by such slender means, as our supposed magnetick Emanations: and therefore think it our duty to satisfie you concerning this Doubt. We Answer (1) That a very great quantity of Iron (proportionately) is easily and nimbly rusht into the arms of a Loadstone meerly by Rays of most subtle particles, such as can be discovered no way, but by their Effect. (2) That stones, and o∣ther massy Concretions have no such great ineptitude, or Resistence to

motion, as is commonly praesumed. For, if a stone of an hundred pound weight be suspended in the Aer, by a small wier, or chord: how small a force is required to the moving of it hither? Why therefore should a greater force be required to the Attraction of it downward. (3) When you lift up a stone or other body from the Earth, you can∣not but observe that it makes some Resistence to your Hand, more or less according to the bulk thereof; which Resistence ariseth from hence, that those many magnetique lines, deradiated to, and fastned upon it, by their several Deflexions and Decussations, hold it as it were fast chained down to the Earth, so that unless a greater force intervene, such as may master the Earth Retentive power, and break off the mag∣netique lines, it could never be avelled and amoved from the Earth. And hence is it, that by how much the greater force is imprest upon a stone, at its projection upward; by so many more degrees of excess doth that imprest force transcend the force of the Retentive Mag∣netique lines, and consequently to so much a greater Altitude is the stone mounted up in the Aer: and è contra. Which is also the Reason, why the Imprest Force, being most vigorous in the first degree of the stones ascent, doth carry it the most vehemently in the beginning; because it is not then Refracted: but afterward the stone moves slower and slow∣er, because in every degree of ascention, it looseth a degree of the Im∣prest Force, until at length the same be so diminished, as to come to an Aequipondium with the Contrary force of the magnetique Rays of the Earth detracting it Downward.

Lastly, from hence is it,* 1.28 that the perpendicular Delapse of most Bo∣dies, though of far different weights, is observed to be Aequivelox: contrary to that Axiome of Aristotle (2. de Caelo, text 46) quo majus fuerit corpus, eo velocius fertur, and (text 77.) parvum terrae particulum, si elevatu dimittatur, ferri deorsum, quo major fuerit, velocius moveri; up∣on which the Aristoteleans have grounded this erroneous Rule, Velo∣citates gravium descendentium habere inter se eandem proportionem, quàm gravitates ipsorum, that the Velocities of Heavy bodies falling downward have the same proportion one to another as their Gravities have.

And the Reason of this Aequivelocity of Unequal weights, seems to be this; that of two Bullets, the one of only an ounce, the o∣ther of an hundred pounds weight, dropt from the battlements of an high tower, at the same instant, though the Greater Bullet be attra∣cted by more magnetique lines deradiate from the Earth, yet hath it more particles to be attracted, than the Lesser: so that there being a certain Commensuration betwixt the Force Attractive, and the quan∣tity of Matter Attracted; on either part the Force must be such, as sufficeth to the performance of the motion of either in the same space of time; and consequently, both the Bullets must descend with equal Velocity, and arrive at the surface of the Earth in one and the same mo∣ment. All which that Lynceus, Galilaeo well understood, when (in the Person of Salviatus) desiring to calculate the time, in which a Bullet might be falling from the concave of the Moon to our Earth; and Sagredus had said thus to Him, Sumamus igitur globum determinati

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with the great body or Globe thereof; yet is it not Congregative of the whole Globe to any thing else, as if the Globe of the Earth were to be united to the Moon, or any other Orbe in the World. Nor can it be affirmed, that Gravity, or this Virtue to motion Direct, is conceded to the Terraqueous Orbe, to the end it should, at the Creation, carry it self to that place, which is Lowest in the Universe; or being there posited, constantly retain it self therein: since in the U∣niverse is neither Highest, nor Lowest place, but only Respectively to the site of an Animal, and chiefly of Man, whose Head is accounted the Highest, and Feet the Lowest part; in the same manner as there is no Right, nor Left side in Nature, but comparatively to the site of the parts in mans body, and in reference to the Heavens. For, those Lateralities are not determined by any general and certain standard in Nature: but va∣riously assigned according to our Imagination. The Hebrews, Chaldeans, and Persians, confronting the Sun at his arising in the East; place the Right side of the world in the South: as likewise did all the Roman South∣sayers, when they took their Auguries. The Philosopher takes that to be the East, from whence the Heavens begin their Circumgyration: and so assigns also the right hand to the South. The Astronomer, regar∣ding chiefly the South and Meridian Sun, accounts that the Dextrous part of Heaven, which respecteth his right hand, and thats the West. And Poets, differing from all the rest, turn their faces to the West, and so assign the term of Right to the North: for otherwise Ovid must be guilty of a gross mi∣stake in that verse, Utque duae dextrá zonae, totidemque sinistrâ. Hence is it, that as the East cannot be the Right side of the World, unless to Him, who faceth the North: so is the Vertical point of the world not to be accounted the Highest part of the Universe, but onely as it respect∣eth the Head of a man standing on any part of the Earth; because, if the same man travail to the Antipodes, that which was before the Highest, will then be the Lowest part of the World. This considered, we must praefer that solid opinion of Plato, that in the World there is an Extreme, and a Middle Place, but no Highest and Lowest; to that meer∣ly petitionary one of Aristotle, that all Bodies tend toward the Centre of the Earth, as to the Lowest place in the Universe.

How, saith the offended Peripatetick,* 1.29 the meerly Petitionary opinion of Aristotle? Why, do not all men admit that to be the Lowest part of the World, which is the Middle or Centre thereof? And is not that the Centre of the Earth?

And our Reply is, that, indeed, we can admit Neither. (1) Because, should we allow the World to have a Middle, or Centre; yet is there no necessity, that therefore we should concede the Centre to be the Lowest place in the World▪ no more than that the Navil, or Central part of a man should therefore be the Lowest part. For, to speak like men, who have not enslaved their reason to praejudice; what is opposed to the Mi••dle, is not suprem, but Extreme: and Highest and Lowest are oppo∣site points in the same Extreme. So likewise in the Terrestrial Globe, whose middle part we account not the Lowest, but the contrary point in the sphear: since, otherwi••e we must grant the Earth to have a double Infinity, one in regard of its Centre, the other in respect of the extreme

points of it•• 〈◊〉〈◊〉▪ according to which the Antipodes are Lowest to us▪ and we 〈◊〉〈◊〉 to them.

(2) Wh•• 〈◊〉〈◊〉 praetend to demonstrate▪ that there is an ••xtreme in the Universe▪ 〈…〉〈…〉 ••here be, ••o determine wher•• ••nd wh••t it is: ••nd upon con∣sequence▪ 〈◊〉〈◊〉 the Universe hath an•• Centre, and wher•• that Centre is. Tis mo•••• ••han Galilaeo durst▪ as appears b•• ••hat his modest confession▪ N••scimus 〈…〉〈…〉 ubi sit Universi centrum, n••q•••• an si•••• quodque, si maxime d••tur▪ aliud 〈…〉〈…〉 nisi pun••tum imaginari••m, adeoque nihilum, omni facul••ate 〈…〉〈…〉. (〈◊〉〈◊〉 Cosmici dialog. 1 p••g. 22) Besides, we see i•• to be▪ an•• ••••on very good ground••, d••••put•••• ••mongst the most Curious an•• Learn•••• 〈◊〉〈◊〉 o•• ••he world▪ whether the ••••xt star•• are m••ved about the Earth, or th•• ••arth by a Diurnal motion upon it•• own a••is▪ Whether the ••ix•• stars 〈…〉〈…〉 one and the same con••ave superfi••••: or rath•••• (as the Pla∣nets▪ which ••••••••i••hstanding the deluded sight, are demonst••••ted not to be in on••▪ bu•• 〈◊〉〈◊〉 sphere•• som•• farther ••rom▪ some ne••r•••• to the Earth▪ disper••e•• 〈…〉〈…〉 immense space▪ For▪ from he••ce▪ that th•• Distance be∣twixt 〈…〉〈…〉 u•• i•• so vast▪ th••t our sight not discerning the large spaces in∣tercepted 〈…〉〈…〉 them in the•••• several orbe••▪ they all appe••••e at the same distanc••▪ 〈…〉〈…〉 same ••ircum••••rence▪ wo•••• C••ntre must be there▪ wher•• th•• Eye 〈…〉〈…〉 sel•• about▪ doth behold them: so that in whatsoever part of the 〈◊〉〈◊〉 ••pace o•• th•• World▪ whether in the Moon▪ Sun, or any o∣the•• Orb▪ 〈◊〉〈◊〉 ••hall imagin•• your sel•• to be placed; still you must, accor∣ding to 〈…〉〈…〉 o•• your sight, judge the World to be spherical, an•• that you 〈◊〉〈◊〉 in the ver•• centre of that Circumference, in which you con∣ceive all th•• 〈◊〉〈◊〉 stars t•• be constitute.

Trul••▪ 〈◊〉〈◊〉 worthy th•• admiration of a wise man, to obser••e, that the ve∣ry Plane•••• 〈◊〉〈◊〉 admitted by the Aristoteleans to have cert••••n motions 〈…〉〈…〉 be moved in such Gyres, as have not their Centres in the 〈…〉〈…〉 immensly distant from it: and yet that the same Persons 〈…〉〈…〉 Contradict th••mselve••▪ as to account that the Centre o•• the 〈…〉〈…〉 common Centre of the world, about which all the Coelest••∣al 〈…〉〈…〉 Dif••••culties perpended▪ w•• cannot infall••∣bl•• 〈…〉〈…〉 Earthy B••••ie••, when descending in direct line•• to 〈…〉〈…〉 toward the Centre of the Wor••d: and thoug•• the•• 〈…〉〈…〉 toward the Centre of the World, yet doth that seem 〈…〉〈…〉 is also by Accident, that they are carried towa•••• the 〈…〉〈…〉 Earth▪ in which as being a meer imagin••ry Point, the•• 〈…〉〈…〉 attain quiet. For, per se▪ they are carried towar•• the 〈…〉〈…〉 Whole▪ or Princip••e; and having once attained there∣••••, 〈…〉〈…〉 as they no more seek to pass on from thenc•• 〈…〉〈…〉 ••entre▪ tha•• an Infant received into his Nurses armes or lap▪ 〈…〉〈…〉 into he•• Entrals: and meerly per Accidens is it, that they 〈…〉〈…〉 the Centre of the Earth▪ because tending in the neeres•• 〈…〉〈…〉 line to the place o•• their quiet, they must be directed 〈…〉〈…〉, since if we suppose that direct line to be continued, it must 〈…〉〈…〉 the Centre of the Earth. And thus have we left no stone 〈…〉〈…〉 all Aristotles Theory of Gravity, which is, that Weight is a Quality es••••ntially inhaerent in all terrene Concritions, whereby they sponta∣n••ous••y 〈◊〉〈◊〉 ••oward the Centre of the Terrestrial Globe, a•• to the Common Cen••••e 〈…〉〈…〉 place in the Vniverse. The whole Remainder of our prae∣s•••••• 〈◊〉〈◊〉▪ the••e••o••e, concerns our farther Confirm••tion of that 〈…〉〈…〉 of Gravity, which we have espoused; which is▪ 〈…〉〈…〉 meer Effect of the Magnetique Attraction of the Earth.

Let us therefore once more resume our Argument à Simili,* 1.30 considering the Analogy betwixt the Attraction of Iron by a Loadstone, and that of Terrene Concretions by the Earth; not only as to the Manner of their re∣spective Attractions, but cheifly as to the parity of Reasons in our judge∣ments upon their sensible Effects. When a man holds a plate of Iron of 6 or 7 ounces weight, in his hand, with a vigorous Loadstone placed at con∣venient distance, underneath his hand; and finds the weight of the Iron to be encreased from ounces to pounds: If Aristotle on one side should tell him, that that great weight is a Quality essentially inhaerent in the Iron, and Kepler or Gilbert, on the other, affirm to him, that that weight is a quality meerly Adventitious, or imprest upon it by the Attractive influence of the Loadstone subjacent; 'tis easie to determine, to which of those so con∣trary judgements he would incline his assent. If so, well may we conceive the Gravity of a stone, or other terrene body, to belong not so much to the Body it self, as to the Attraction of that Grand Magnet, the Terraqueous Globe lying underneath it. For, supposing that a Loadstone were, unknown to you, placed underneath your hand, when you lifted up a piece of Iron from the earth; though it might be pardonable for you to conclude, that the great weight, which you would observe therein, was a Quality essen∣tially inhaerent in the Iron, when yet in truth it was only External and At∣tractitious; because you were ignorant of the Loadstone subjacent; yet, if after you were informed that the Loadstone was placed underneath your hand, you should persever in the same opinion, the greatest Candor imagina∣ble could not but condemn you of inexcusable pertinacity in an Error. Thus also your ignorance of the Earths being one Great Loadstone may excuse your adhaerence to the erroneous position of Aristotle, concerning the formal Reason of Gravity; but, when you shall be convinced, that the Terrestial Globe is naturally endowed with a certain Attractive or Magne∣tique Virtue, in order to the retention of all its parts in cohaerence to it self, and retraction of them when by violence distructed from it, and that gravi∣ty is nothing but the effect of that virtue; you can have no Plea left for the palliation of your obstinacy, in case you recant not your former per∣suasion.

Nor ought it to impede your Conviction, that a far greater Gravity,* 1.31 or stronger Attractive Force is imprest upon a piece of Iron by a Loadstone, than by the earth; insomuch as a Loadstone suspended, at convenient distance, in the aer, doth easily elevate a proportionate mass of Iron from the earth▪ because this gradual Disparity proceeds only from hence, that the Attra∣ctive Vertue is much more Collected or United in the Loadstone, and so is so much more intense and vigorous according to its Dimensions, than in the Earth, in which it is more diffused; nor doth it discover how great i•• is in the ••ingle or divided parts, but in the Whole of the Earth. Thus, if you lay but one Grain of salt upon your tongue, it shall affect the same with more saltness, than a Gallon of Sea-water: not that there is less of salt in that great quantity of Sea Water, but that the salt is therein more dif∣fused.* 1.32

But to lay aside the Loadstone and its Correlative, Iron, and come to our taste and Incomparative Argument; since the Velocity of the motion of a stone falling downward, is gradually augmented, and by the accession

of new degrees of Gravity, grows greater and greater in each degree of its Descen•• 〈◊〉〈◊〉 that Augmentation, or Accession of Gravity, and so of Veloc••••••▪ seems no•• so reasonably adscriptive to any other cause, as to this, that it is the Attraction of the Earth encreasing in each de∣gree of the stones Appropinquation to the Earth, by reason of the greater Density or Union of its Magnetique Rayes: What can be more 〈◊〉〈◊〉 than that the First degree of Gravity, belonging to a stone no•• 〈◊〉〈◊〉 moved, should arise to it from the same Attraction of the 〈◊〉〈◊〉 When, doubtless, it is one and the same Gravity that causeth both those Effects; the same in Specie, though not in Grad••••: 〈◊〉〈◊〉 no Quality can be better intended, or augmented, than by an Accession of more Degrees of force from the same Quality.

SECT. III.

LAstly▪ as concerning LEVITY, which is vulgarly reputed the 〈…〉〈…〉 Gravity,* 1.33 and by Aristotle defined to be a Quality in∣haerent in 〈…〉〈…〉 Bodies▪ whereby they spontaneously tend upward; we understand it to be nothing a less Gravity: and so that Gravi∣ty and 〈◊〉〈◊〉 are Qualities of Concretions, not Positive, or Abso∣lute▪ but 〈◊〉〈◊〉 Comparative, or Respective. For, the same Body ma•• be 〈…〉〈…〉 be Heavy, in respect to another that is Lighter; and Light▪ 〈…〉〈…〉 to another that is Heavier. For Example, let us compare a Stone▪ Water, Oyle, and Fire (which we have formerly an∣numerated 〈◊〉〈◊〉 Terrene Concretions) one to another; to the end that our 〈◊〉〈◊〉 may be both illustrated and confirmed at once. Wa∣ter▪ we 〈◊〉〈◊〉 being poured into a ves••el, immediately descends to the bottom 〈…〉〈…〉 and if permitted to settle, doth soon acquiesce: but▪ upon 〈◊〉〈◊〉 ••ropping of Stone into the same vessel, as the Stone descends▪ 〈◊〉〈◊〉 Water ascends proportionately to give it room at the bottom. And Oyle, infused into a vessel alone, doth likewise instant∣ly 〈◊〉〈◊〉 and remains quiet at the bottom thereof: but, if Water be poure•• ••••ereupon▪ the oyle soon ascends, and floats on the sur∣face of the Water. If the Vessel be repleat only with Aer, the Aer 〈◊〉〈◊〉 therein: but when you pour oyle into it, the Aer instantly as••ends, and resignes to the oyle. Lastly, thus Fire would be ••mmediately incumbent upon the surface of the Earth, and there 〈◊〉〈◊〉; but that the Aer, being circumstant about the superfice 〈◊〉〈◊〉 the Terrestria•• Globe, and the more weighty body of the two 〈◊〉〈◊〉 extrude it thence by depressure, and so impell ••t up∣wards 〈◊〉〈◊〉 make room for it self beneath. And thus are all these bodies 〈…〉〈…〉 and Light, Comparatively or Respectively. The 〈…〉〈…〉 all is the Stone, as being the most strongly at∣tracted 〈…〉〈…〉 Earth: or, is the least Light among them all, as being 〈…〉〈…〉 abduced from the Earth. And, Water, which is Light, 〈…〉〈…〉 of the Stone, is yet▪ Heavy in compa••••son of Oyle:

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seu fumum rapi in sublime, & extrudi suum extra locum, ideoque statim langues••••re tanquam confessâ causâ violentiae, quae terrestri ma∣teriae illata fuit•• quapropter Levitatem non dari, aut non esse Connatu∣ralem hisce corporiubs. Conclude also, with Us; that in the Earth indeed, there are Direct Motions Upward and Downward: but those Motions are proper only to the Parts (as Gravity and Levity are likewise proper only to the Parts) not to the Whole, or Globe of the Earth.

Notes

• * 1.1

  Art. 1. The Motive Virtue of all Concretions, derived from the essential Mobility o•• A∣toms.
• * 1.2

  Art. 2. 〈…〉〈…〉 Part••
• * 1.3

  〈1 paragraph〉〈1 paragraph〉
• * 1.4

  〈1 paragraph〉〈1 paragraph〉
• * 1.5

  Art. 5. What the Active Faculty of a thing, is.
• * 1.6

  Art. 6. That in Nature every Faculty is Active▪ none Passive▪
• * 1.7

  Art. 7. A Peripatetick Contradiction, assuming the Matter of all Bodies to be devoid of all Activity; and yet desuming some Facul∣ties â tota sub∣stantia.
• * 1.8

  Art. 8. That the Fa∣culties of Ani∣mals (the Ra∣tiocination of man only ex∣cepted) are Identical with their spirits.
• * 1.9

  Art. 9. The R••••sons of the Coexi∣stence of Va∣rious Faculties in one and the same Concre∣tion.
• * 1.10

  Art. 10. Habit defined.
• * 1.11

  Art. 11. That the Rea∣son of all Ha∣bits in Ani∣mals, consist∣eth principal∣ly in the con∣formity and fl••xibility of the Organs, which the r••∣spective Facul∣ty makes use of, for the per∣formance of its proper Actions.
• * 1.12

  Art. 12. Habits, acqui∣rable by Bruits: and common not only to Vegetables, but also to some Minerals.
• * 1.13

  Art. 1. Gravity, as to ••••s Essence, o•• Formal Reason, very obscure.
• * 1.14

  Art. 2. The opinion of Epicurus, good as to the Cause of Com∣parative: insuffi∣cient as to the Cause of Ab∣solute Gravity.
• * 1.15

  Art. 3. Aristotles opi∣nion of Gravi∣ty, recited.
• * 1.16

  Art. 4. Copernicus the∣ory of Gravi∣ty, insatisfacto∣ry; and where∣in.
• * 1.17

  Art. 5. The Determi∣nation of Kep∣ler, Gassendus, &c. that Gra∣vity is Caused meerly by the Attraction of the Earth: e∣spoused by the Author.
• * 1.18

  Art. 6. The Ext••rnal Principle of the perpendi∣cular Descent of a stone, pro∣jected up in the Aer; must be either De∣pell••nt, or At∣••rahent.
• * 1.19

  Art. 7. That the Re∣sistence of the Superior Aer is the only Cause which gradu∣ally refract∣eth, and in fine wholly overcometh the Imprest Force, where∣by a stone pro∣jected, is ele∣vated upward
• * 1.20

  Art. 8. Tha•• the Aer, distracted by a stone violent∣ly ascending, hath as well a Depulsive, as a Resistent Fa∣culty; arising immediately from its Elate∣rical, or Resto∣rative motion.
• * 1.21

  Art. 9. That neverthele•••• when 〈…〉〈…〉 on high in the 〈…〉〈…〉 no Caus•• can 〈◊〉〈◊〉 Down∣w•••••• Motio••, 〈…〉〈…〉.
• * 1.22

  Art. 10. A••gument, that 〈◊〉〈◊〉 Terraque∣ous Gl••be is endowed with a certain Attra∣ctive Faculty, in order to the Detention and Retraction of all its Parts.
• * 1.23

  Art. 11. What are the Parts of the Terrestrial Globe.
• * 1.24

  Art. 12. A Second Argu∣ment that the Earth is Mag∣netical.
• * 1.25

  Art. 13. A Parallelisme betwixt the Attraction of Iron by a L••ad••tone, a••d the Attraction of Terrene bodies by the Earth.
• * 1.26

  Art. 14. That as the sphere o•• the Loadstones Allective Vir∣tue is limited: so is that of the Earths magne∣tism.
• * 1.27

  Art. 15. An Obiection of the Dispropor∣tion between the great Bulk of a large 〈◊〉〈◊〉 and the Ex••••••∣••y of the sup∣posed magne∣tique Rays of the Earth: Sol∣ved by three w••ighty Rea∣sons.
• * 1.28

  Art. 16. The Reason of the Aequivelo∣city of Bodies, of different weights, in their perpendi∣cular Descent: with sundry un∣questionable Authorities to c••nfirm the Hoti thereof.
• * 1.29

  Art. 18. That the Cen∣tre of the Uni∣ver••e is not the L••w••st part ••••••reof: nor the Centre of the Earth▪ the Centre of the World.
• * 1.30

  Art. 19. A Fourth A••gu∣ment, that Gra∣vity is only Attraction.
• * 1.31

  Art. 20. Why a greater Gravity, or stronger At∣tractive force is ••mprest ••p∣on a piece of iron by a Loadstone, than by the Earth.
• * 1.32

  Art. 21 A ••ifth Argu∣ment, almost Ap••••ictica••••; that Gravity 〈◊〉〈◊〉 the Effect 〈◊〉〈◊〉 the Earth ••••••••raction.
• * 1.33

  Art. 1. ••word nothing 〈…〉〈…〉