Dr. Willis's practice of physick being the whole works of that renowned and famous physician wherein most of the diseases belonging to the body of man are treated of, with excellent methods and receipts for the cure of the same : fitted to the meanest capacity by an index for the explaining of all the hard and unusual words and terms of art derived from the Greek, Latine, or other languages for the benefit of the English reader : with forty copper plates.

CHAP. II. Of the Motion and Heats of the Blood.

SO much for the Anatomy of the Blood, as to its primary Elements and constitutive parts, into which it is sensibly wont to be resolved; also as to its Affections, which ap∣pear clearly, by the comparing it with Wine and Milk: it remains for us next to en∣quire concerning the motion of the blood, both Natural, viz. by the help of what Ferment, and by what swelling up of parts, it is Circulated in a perpetual motion through the Vessels) and preternatural, viz. for what Causes, and what fury of parts, when it boils up above mea∣sure in the Vessels, and conceives Feaverish Effervescences. These being rightly unfolded and premised, we will enter upon the Doctrine of Feavers.

Concerning the Natural Motion of the Blood, we shall not here enquire of its Circulation, viz. by what Structure of the Heart and Vessels, it is wheeled about after a constant manner, as it were in a Water-Engine; but of its Fermentation, viz. by what mixtion of parts, and mutual action of them together among themselves (like Wine fermenting in the Ton) it continually boils up. And this kind of motion (as it were truly an intestine war of the Blood) depends both on the Heterogeneity of the parts of the Blood it self, and on the various Ferments, which are breathed into the mass of the Blood from the Bowels.

As to the first: those things which have altogether like Particles, do not ferment, where∣fore neither distilled Waters, Chymical Oyls, Spirits of Wine, or other simple Liquors are moved, as hath been already observed: but I have said, that Blood, according to the Nature of things quickly irritable, doth consist of a proportionate mixture of the Elements; in which Spirits, for that they are very nimble, continually strive to expand themselves and to fly away: but being entangled by the more thick Particles of the rest, they are detained in their flight. And being detained after this manner, they toss about, break to pieces, and very much subti∣lize the more thick little Bodies, by which they are hindred; they volatilize the Salt, otherwise fixed; by a most minute kneading, and by the adhesion of it, they perfectly dissolve the Sul∣phur, compacted in it self, and not miscible with the rest, and boil it in the Serum. They break the Earth, even to its smallest parts, and mingle it with the rest. But in the mean time, by the striking and molding the Salt and the Sulphur, Esfluvia's of heat plentifully proceed, which being mixed with the rest, and on every side diffused, increase the motion of the Fermentation. And after this manner all being most minutely broken and diluted with watery Particles, they constitute the Liquor of the Blood,, which whilst in the Vessels, as Wine shut up in a Pipe, continually ferments, and according to all its Particles is in perpetual motion.

But the Fermentation of Wine and of Blood, differs in this; that in Wine there is no wast∣ing of the old parts, and a coming again of new; but the Liquor being shut up in the Vessel, remains still the same: but'tis otherwise in Blood, in which some parts are continually destroyed, and in their place others are always generated anew. In Wine, the times of crudity, matura∣tion, and defection, are distinct, and are successively performed in the whole: In Blood, that threefold state is celebrated at the same time and by parts: Fermentation being once begun in Wine, is continued even to the end; but in Blood, because it is washed still with crude Juices, it ought still to be renewed; by which means, the Nutritious Particles, not of kin, are assi∣milated to the rest of the Latex; wherefore, for this work, besides the Fermentation once be∣gun in the Blood, there is need of some Ferments, which may continue the same, otherwise about to leave off.

That Ferments are required for the making of Blood, this is an Argument; that when they are wanting by Nature, they are with good success supplied by the work of Art: for fixed Salts, Alkali Salt, Extracts, Digestives, Openers, and especially Chalybeat Remedies, help for this reason, that, as it were by a certain Ferment, they restore anew, the weak, or almost extinct Ebullition, or boyling of the Blood.

As to what respects the Natural Ferments, very many may certainly be formed, and in divers parts, or hid in the Bowels; for any Humor in which the Particles of Salt, Sulphur or Spi∣rit, being much exalted, are contained, puts on the Nature of a Ferment: after this manner, the flowring or dregs of Beer or new Wine, being kneaded with Meal, and the Mass kept to sowrness, come under this rank, by which new Beer, and the like Liquors, as also the Mass of Bread, are more excellently fermented. In like manner in the Ventricle, a sowrish Humor parti∣cipating of exalted Salt, there helps Concoction: and in the Spleen, the feculeneies of the Blood from Salt and Earth being exalted, go into a Ferment-

How much vigor comes to the Blood from the Womb and Genital Parts, appears from hence, because by the privation, or evil disposition of them, follow, in Maids the Green-sickness, in Men, Barrenness or loss of Virility, want of Beard, and a shrill Voice. But the chief Ferment, that serves for sanguification, is established in the Heart; for this is the chief fire-place, in which the cruder Particles of the Chyme, are as it were inkindled, and acquire a volatileness: which thing may be confirmed by many reasons, but especially by its effects, which we suffer in the Precordia, as often as the Blood ferments more or less than it ought to do: for when it is too much inkindled in the Heart, it is agitated impetuously, as it were by fires put under it; the signs of whose immoderate Ebullition are, a deep pulse and vehement, then almost an intole∣rable heat in the Precordia, with a vehement thirst; on the other side, when the Fermentation of the Blood is lessened in the Heart, we are affected with an anhelous, and difficult respiration upon any motion; as may be perceived in the Dropsie, Cachexia, and Yellow Jaundice: the rea∣son of which is, not because the Lungs are stuffed, or filled full of a tough or clammy matter; but because the Blood doth not rightly ferment, in that Repository of Fermentation; wherefore, being fallen into its Bosom, it is not presently Rarified; nor doth it soon leap forth into the Lungs, but being apt to stagnate, and remain there, causes an oppression of the Heart it self; for the helping of which, frequent breathing is made, that the Blood being let forth into the Lungs, succour might be brought to it: but if by motion or exercise, the Blood be more pro∣voked into its Ventricle, than can be derived by respiration, or the pulse, into the Pneumonic Vessels, there is danger of choaking. The like happens in those that are dying: when the pulse is very small, and the Blood being heaped up in the Heart for want of Fermentation, begins to stagnate and to clodder, we then breath deeply, with a no•…•…se and elevation of the breast; to wit, the Blood with the ultimate endeavour of Nature, and the whole force of the Lungs, as long as it is able to be done, is emptied forth into the Lungs, lest residing in the Heart, it should wholly choak it.

Therefore, Motion and Heat, in the Blood, depend thiefly on two things, viz. partly on its own proper disposition and constitution, by which, it being forged very greatly with active Principles of Spirits, Salt, and Sulphur, of its own accord swells up, or grows turgid in the Vessels, even as Wine in the Ton: and partly on the Ferment implanted in the Heart, which very much rarifies the Liquor passing through its Bosom, and makes it to leap forth with a frothy heat: that the Blood, which is quietly instilled to the Heart through the Veins, running gently like a River, from thence leaping forth through the Arteries, (like a Torrent) with noise and rage, might be carried forward, to all the parts of the whole Body. By what means this is done, though it is not easie to explicate Mechanically, yet the manner, and some not improbable reasons of this thing, are delivered by most Learned men, Ent, Cartes, and others. They sup∣pose indeed, as it were a fire to be set in the Chimny of the Heart, which presently inkindles the Blood infused through the Veins, (even as a flame put to Wine burns it) which being so inkindled, by its deflagration (like lightning) passes most swiftly through the Arteries: so that heat, a most rapid motion, and Effluvia sent by Perspiration, are wont to proceed from the accension of the Blood in the Heart only. Hogelandus affirms, that there is a Ferment hid in the Bosom of the Heart, that compels the Liquor of the Blood to boil up, and to grow hot, with heat, and a plentiful emission of Soot, just like Spirit of Nitre, when it is poured on the Butter of Antimony: so that the Blood, flowing in gently through the Veins, being forthwith Rarified into spume and vapour by the ferment of the Heart, runs very impetuously through the passages of the Arteries. 'Tis almost the same thing, whether it be said to be done, either by this, or by that way: for the alteration which the Blood receives in the Heart, may be equally deduced from a flame, or a Nitrous Sulphureous ferment, there supposed to be placed. Because, whilst the Blood slides into the Ventricles of the Heart, presently the frame of the Liquor is loosned, and the active Particles, especially the Spirituous and Sulphureous, the bond of the mixture being broke, do leap forth from the rest, and strive to expand themselves on every side; but being kept in by the Vessels, and being forced together with the remaining Liquor, through the open passages of the Arteries, they rush with violence, and swelling up by the way they can find, and by that means, diffuse Effluvia of heat, through the whole body: there is little difference, whether the expansion of the Particles of the Blood, and exertion into the liberty of motion, be said to be done by Accension, or by Fermentation, forasmuch as by either way, the frame of the Blood may be so unlocked, that from thence the Particles of Spirit, Salt, and especially of Sulphur, being incited into motion, (as it were by an inkindled fire) may impart heat to the whole Body.

But this Rarefaction, or Accension of the Blood in the Heart, very much depends upon the disposition and constitution of the Blood it self: for if its Liquor be rightly cocted, being made volatile, and (like rich Wine) brought to maturity, it then Ferments there after its due man∣ner, whereby the soluted Particles of the Spirits and Sulphur, diffuse an equal, and moderate heat to all parts. But if the blood, by reason of an ill manner of feeding, and want of Con∣coction, be crude and watry, then it is less inkindled in the Heart; and from thence follow a

frigid intemperance of the whole, difficult breathing and wheesing, with a weak pulse, and lan∣guishing; as in Cachectical people, those distempered with the Green-sickness, and such as are about to die, may be perceived: but if the Blood becomes too luxuriant, and apt to grow tur∣gid, by reason of plenty of Sulphur being carried forth, or of its Effluvia being restrained, or of eating hot things; either its Accension or Fermentation in the Heart, is very much increased, so that from thence a Feaverish heat, and greater effervescencies than usual, are stirred up in the whole. This various Fermentation of the Blood in the Heart, according to the various temper of the same, may be illustrated by the example of Wine: fresh Must, that is yet crude, though it be boiled, or put on the fire, will not burn; but this being purified and brought to maturity, is easily inkindled, but sends forth a small flame, and quickly out. The same at first growing hot, or otherwise warmed, if inkindled, is greatly inflamed, and for the most part is consumed by its burning.

Whilst the Blood, after this manner being rarified, or inkindled in the Heart, and from thence growing hot, through the passages of the Vessels, is resolved into minute parts, some little bodies depart from its loosned frame, which refuse at last to be united, and fitted with the rest of the Liquor: but these are of a twofold Nature; either thin, which like smoke from the burning fire, or Effluvia from a Fermenting Liquor, do evaporate from the Liquor of the Blood, by a constant Diaphoresis, through the breathing holes of the Body; or more thick, which like ashes left after burning, or the settling dregs after Fermentation, ought to be soon strained from the mass of Blood, and to be carried forth of dores: for otherwise, by their confusion, they produce notable perturbations in the Blood. Whereby the Blood growing more hot, is dis∣solved in the Heart, therefore these Recrements, both Fuliginous and Earthy, are more plenti∣fully heaped together; and when by reason of too great congestion, they cannot be presently subdued and secluded from the mass of Blood, they bring forth a swelling up of the Blood and Fea∣verish Heats.

Concerning the Motion, Heat, and Natural Fermentation of the Blood, in the equal tenor of which, the means of our Health consists, what hath hitherto been spoken, shall suffice. We will treat a little more largely of the preternatural, or too great effervescency, on which the Types, and Paroxysms of Feavers depend: I call that too much, or Preternatural Fermentation, when the Blood, (like a Pot boiling over the fire) grows hot above measure, and being rarified with a swelling spume, distends the Vessels, excites a more quick pulse, and like a sulphureous Liquor, having taken fire, diffuses a burning heat on every side.

This kind of motion or Fermentation of the Blood, will be best of all illustrated by an example of Wines growing hot. For Wines, besides the gentle and equal Fermentation, by which they are at first purified, at some times do so remarkably grow hot, and boil up, that they fly out of the mouth of the Vessel, and if they are closely stopped up, cause it to burst in pieces. After this man∣ner, as if struck with fury, unless they are immediately drawn away from the Tartar; or their Lees into another Vessel, they will not cease from growing hot, until the Spirit being very much loosned, and the Sulphur or Salt too much exalted, they are either made unsavory, or degenerate into a sowrness.

Such an Effervescency is wont to be stirred up for two causes chiefly: First, When any extra∣neous thing, and not miscible, is poured into the Ton, (so some drops of Tallow, or Fat, being dropped into the Cask, will produce this motion) or secondly, when Wines being enriched with too rich a Lee or Tartar (by reason of the sulphureous parts being above measure exalted) con∣ceive heats of their own accord, and exceedingly boil up. For in whatsoever substance Sulphur abounds, and its Particles being loosned from the mixture, consociate together, and are bound close in one, there such immoderate heats are procured.

After a like (tho' not wholly the same) manner, whereby Wines grow hot, the boiling up of the Blood is induced; to wit, either what is forein, and not akin to the Blood, is mixed with it, that when it is not assimilated, is wont to cause a Perturbation, and growing hot, until that Heterogeneous thing, is either subdued or cast forth of dores; and the Particles of the Blood being confused and troubled, are at last shaken forth, and that they get again their former place and position in the mixture. Or, Secondly, the Blood grows hot above measure, because some Principle, or its constitutive Element, (viz. Spirit or Sulphur) is carried forth beyond its Na∣tural temper, and becomes enraged; whereby indeed the Particles of this or that, being not agreeable to the rest, are loosned from the mixture; being loosned, they become more violent than they ought, shake much the Liquor of the Blood, and bring forth a heat, which is not al∣layed, till the Blood being as it were inflamed, burns forth with the long fire of a Feaver. By either way, whether the Blood grows hot in the Vessels, by reason of the pouring in of a thing not miscible, or by reason of the rage of the Spirit, or Sulphur being carried forth, because from thence its frame is more loosned, therefore it is more inkindled in the Heart; and the active Particles first loosned from the Ferment there implanted, do grow exceeding hot, leap forth from the mixture, and disperse on every side by their motion, a strong heat, and as it were fiery: but yet with this difference, that the Effervescency, which depends upon the

mingling of some extraneous thing with the Blood, is for the most part short, or renewed, which, when what was Heterogeneous is separated or subdued, is quieted of its own accord, and the shaken parts of the Blood, and put out of order, easily return to their Natural site and dispo∣tion. But the Ebullition which arises from the inordination of the Spirit or Sulphur being enra∣ged, is continual; to wit, here the whole mass of the Blood is so loosned, and dissolved from the strict bond of the mixture, that as an Oily Liquor having taken fire, it ceases not to grow hot, or to be inflamed, till the Particles of Spirit, or Sulphur, or the combustible matter, be for the most part burnt out.

There remains yet a third manner of Preternatural Fervency, whereby the Blood is subject to alteration, which happens not to Wine, but most often to Milk; viz. when at any time, from a Morbific cause, a coagulation of its Liquor is induced, so that its substance is poured forth, and goes into parts, and there is a separation made of the thick and earthy from the thin; by which means the Blood is not fitly circulated in the Vessels, but that its congealed portions, being apt to be fixed in the extream parts, or to stand still in the Heart, do interrupt the equal motion, or grievously hinder it: For the sake of the restoring of which Effervency, greater are wont to be stirred up in the Blood, to wit, such as happen ordinarily in a Plurisie, the Plague, Small Pox, or the Venereal Disease.