A PHYSICO-MEDICAL ESSAY Concerning the late frequency of APOPLEXIES.  
Together with a general Method of their Prevention, and Cure. In a Letter to a Physician.  
By WILLIAM COLE, M.D.  
OXFORD, Printed at the THEATER. 1689.   

Imprimatur. GILB. IRONSIDE Vicecan. OXON.  
Feb. 20. 1689.   

To my much esteemed Friend Samuel Kimberley, Dr. in Physic.  
Dear Sir.  
THough I must look on your request, to have my thoughts of the cause of the greater frequency of Apoplexies these late years, than formerly, as only an instance of your modesty, in giving a deference to the judgement of others, when, I doubt not, your own notions, if you please to draw them forth, can better satisfy both yourself, and all men else, than any I can produce; yet that I may not be wanting to the friendship I have so long in reality professed for you, I shall for once venture to present them to you, however unaccurate; which, being addressed to a friend, may expect to be candidly interpreted, although they bring not the satisfaction you expect.  
'Tis true; I have heard the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 questioned; it being alleged that this distemper might, amongst the vulgar, be ranked under some other class, in regard 'tis not to be presumed they should know to assign the right names to diseases; till the fate of a Great Prince, our late most gracious Sovereign, commonly reported to have died of it, might give a general notion of the name, as well as imprint apprehensions of the danger. And indeed it may be suggested, that such an accident, happening to so great a person, may make stronger impressions on men's minds, than when it falls on those who make a lesser figure, and thence make them take notice of what they would not otherwise have heeded. Besides that the report must, on that account, be the more diffusive; and so being conveyed amongst many of all tempers, must meet with some of very apprehensive ones, whose fears will easily be propagated to others; it being natural to all men to reflect upon what they think carries danger, (especially when 'tis strongly and frequently inculcated) in order to prevent it, if not to have their spirits depressed by it, from whence perhaps such may be more disposed to receive the Ideas (to speak in the language of Helmont) of such a disease.  
But if we duly consider it, we may find, that it hath been both known by Name, and dreaded by those of all Ages. For besides that all practical Authors (from whom the vulgar must be presumed to have first received it) treat of it ex professo by that Name, the very surprise must necessarily excite a notion of it in all, it being so very different in its symptoms and fatality from all other distempers. So that the many accounts continually brought of great persons, as well as those of a lower rank, that have been snatched away by it, are not to be looked upon as only the true notion of it retrived, which was before mistaken, but a real increase of it now; and may too much justify the melancholy apprehensions of the Gentlemen you spoke off, who desire an information concerning it.  
To endeavour then to give a satisfactory answer to your question, 'twil be requisite I consider, though briefly, the particular Seat, Nature, and immediate Causes of the distemper, as also the Disposition of the Part, where 'tis seated, to be affected. And though this disquisition have been so often and learnedly made by many Authors, yet most of them differing from others in some particulars, it may hope your more favourable interpretation, if I do the like from any of them who may perhaps be your favourites, when by their example I show why I do it: since as the notions of all cannot be reconciled, so no man is obliged to think precisely with any other, be his reputation ever so great.  
I propose not to myself to deliver all their opinions (which your own reading supplies you with better than I can) much less solemnly to refute them. But I must necessarily touch on some particulars in a few of them, in order to make out my own thoughts.  
To the First, 'Tis agreed by the generality of Physicians that the Brain is the seat of the Apoplexy; only Helmont places it in the Praecordia (as most explicitly, De Lithiasi, Cap. 9 §. 52, & 70.) whose offence against the Schools, and contempt of Anatomy (though otherwise he must be owned to be a man of great parts and learning) might possibly prompt him, in opposition to the Ancients and their followers, to take up with some opinion, that presented itself with any colour, that might contradict theirs, rather than agree with them even in the most obvious and convictive ones, though ever so clearly demonstrable too upon dissection. For indeed, besides Anatomical autopsy, which is too clear to be contradicted, all the Symptoms argue it to be seated in the Brain. For even in the most sudden seizure, when the persons affected have not time allowed them to declare their perceptions, 'tis evident that the stroke is impressed on the animal faculty in general, by the immediate cessation of its functions, the vital (so called) continuing, for the most part, entire for some time; which must argue the cause to reside about the original of it, the Brain, since from thence only that faileur can so generally be effected. But when it begins with less violence, so that there is any interval betwixt its invasion, and the total defection of the animal functions, they generally complain of, either a vertigo, or a great oppression and pain in the head; upon which presently follow stupidness, somnolency, dazzling of the eyes, a relaxation of all parts of the body, and the like: all which are so evidently deducible from the consideration of the nerves affected at their original, that 'twere time lost farther to prove it.  
But since 'tis not satisfactory enough to assert in general, that the Brain (which is an accurately organised part, in which there is a great variety of cells and vessels, and a considerable difformity of parts one from another) is the seat of this distemper, without determining whether the whole, or any particular region, or part, of it be especially affected, Authors have employed themselves in this search.  
The most celebrated opinion, and which most have followed till this Age, was that of Galen, who assigned the Ventricles for the particular Seat, and supposed a viscous matter got into them to be the cause of it. This opinion, though it might give some account of the interception of the animal spirits, which (according to the ancient doctrine are to actuate the body by being distributed along the nerves, on the account of the compression these must so undergo near their original, which distribution failing, all animal motion, in the parts influenced by the nerves which labour under this compression, must cease; yet (with all deference to the memory of the great Author, as well as to the abettors of it) I conceive, may rather be presumed to suggest a reason of a Palsy, than Apoplexy, and can hardly be made out to be the cause of so sudden a seizure; since such a congestion must be slow, and so the effect generally must come gradually: whereas from a perfect state of health the Apoplexy on a sudden (as the name imports) ordinarily seizes. Besides though the passages of the spinal marrow, and nerves thence arising be thus closed (rather than obstructed; an obstruction being generally, I conceive, in the common acception of the word, understood to be from some matter within their tracts, and not properly from it externally compressing them) whereby the spirits cannot readily descend into them; yet their motion in the Brain may possibly for some time be free enough; and consequently the Souls exercise may be then entire for a while, if not indeed exalted from the confinement those have to the Brain in that case: and 'tis observed many times that, in a Hydrocephalus, Intellection, and other animal faculties fail only gradually, though the Ventricles have been found upon dissection to have been much filled; which they must have been long time a doing. Withal, what is once got into the Ventricles has no farther communication with the animal spirits, being disterminated from the Brain by the interposition of the membranes. But Galen seems not very consistent to himself in this notion, as making the Brain itself (De loc. affectis lib. 3. cap. 10.) to be the seat of it, without there mentioning the Ventricles, whereas before (cap. 7. as well as in other places) he only seated it in these, exclusively to the substance of the Brain.  
But that Hypothesis is now antiquated, and the substance of the Brain, generally owned to be the seat of it, Anatomical observations having, as I said, made it apparent it must be seated there. And though several Authors have diversely explicated it, yet there are two opinions particularly which are now adays most celebrated, and perhaps deserve to be so, both on their own account, as being each of them very specious, though somewhat different from each other, as also of their Authors, the famous Wepfer and Willis. These indeed seem to agree in their notion of the particular seat of it, viz. both of them assigning the Medullar substance of the Brain and Cerebellum for it. But they differ here in that the former considers the whole compage of them both under that name, in contradistinction only to the Ventricles; the now received distinction into Cortical and Medullar (more properly so called) having not been then thought on; and therefore he seems to suppose any part of the substance may be the seat: whereas the latter supposes it to be in the corpus callosum, or true Medullar part according to that distinction; but withal he asserts that the morbific matter is transmitted to it through the Ambitus or Cortical; the Arteries (which are the conduits for conveying it, whatsoever it be, either immediately, or mediately) passing all through it. But they differ in their explication of the mode of production. For Wepfer supposes that the Brain is either denied a sufficient afflux of blood, of which he assigns several causes; or if it have that, yet that the distribution of the spirits into the nerves is hindered either by an obstruction of them at their originals, or their compression. But Willis doubts whether the former of these, the want of a supply of blood, can have place here, since 'tis known there are every where about the Brain (as well as in other parts of the body) mutual Inosculations of the arteries, on the account of which 'tis not to be supposed that all the branches of the Carotides and Vertebral can on a sudden be obstructed, but that if some happen to be so, yet all parts of the Brain must receive the blood quickly enough from those which are free, by means of these anastomosis, and so the nerves may be readily enough supplied; or if these arteries chance to be totally obstructed, he thinks the consequent distemper will not be properly an Apoplexy, but a Lipothymy, or Hysterical affect. From which consideration he deduces, that what makes an Apoplexy must be something in the Brain itself, that causes either a solution of continuity in it, or insinuates itself into the Meditullium Cerebri, or original of the nerves, and there either obstructs the passage of the spirits into them, or else on the account of some narcotick, or other disagreeable quality, dissipates or depresses them. Both these notions may with much greater advantage be had from the learned Authors, than a short abstract; for which too, under this head, I should apologise, this relating to the Cause, but that withal it conduces to determine the Seat.  
But though Dr. Willis have so speciously urged against that tenant, of the non-admission of blood to the Brain, to produce an Apoplexy, yet I suppose that (with all deference to his great judgement) his opinion, that the proper Medullar part of it is the only, or at least most frequent, seat of it, is somewhat too contracted, not to say precarious; and that on the other side, though an Apoplexy may perhaps sometimes begin in the corpus callosum, yet rather and much more frequently, in the Cortical than there, or amongst the nerves at their original. For though 'tis probable the Meditullium cerebri is the place where the soul principally acts, and from whence she dispenses her influence to the rest of the body, and therefore she cannot be said to be disturbed in her actings, and so a distemper be introduced, till that part be disaffected; yet I conceive that part is properly to be reckoned the Seat of a distemper, where the Cause that influentially occasions the defection of nature's due actings, first fixes it self: otherwise I see no reason but that Wepfers denegation of spirits, which Willis oppugnes, might be sufficient both to make, and denominate, an Apoplexy. And indeed that the Cortical is most apt to receive the morbific matter, seems obvious from hence, that in it the arteries are most numerous, and it most lax and yielding; so that when from any occasion the blood is apt to get out of, or, at least distend, its vessels, or indeed but to exude out of them, 'tis probable this may be done more easily here, than in the corpus callosum. 'Tis true, it must be granted that the arteries are disseminated through all parts of it, even to the inmost; otherwise they could neither receive due heat nor nourishment (if at least nourishment come immediately from the blood to any parts but the roots of the Nerval tree, numerously dispersed through the cortex) which vessels though penetrating ever so deep, if they chance either to open, be broken, or become relaxed, whereby they may let go some of the substances they carry (after the manner by and by to be alleged) 'tis obvious must soon supply the matter of a considerable inundation (if I may so call it) of the blood, or those substances of it which are apt to secede, upon these parts of the Brain to which they reach, from the impetuous protrusion from the heart: and the vessels being here tenderest (as all vessels not only are at their extremities, but especially when they run deepest, and proportionally farthest, because than they are smallest) 'tis no wonder that a congestion should soon be made where this is. But yet if we consider their comparatively small number to those in the Cortical, and how they must be better fenced and supported by their being distributed through a more compact substance as the corpus callosum is, there seems less danger of either a congestion, or extravasation, in this region; the strength of the tone of any part mainly conducing to the ready transmission of the perluent liquor. And that this happens most usually in the cortical region, three, of the four instances alleged by Wepfer, seem to evince; in which I conceive it is easy to gather that they were the extime parts of the Brain that were most disaffected, and therefore there seems reason to suppose must be primarily so. But from hence.  
Secondly, The Nature of the distemper may be deduced. And it seems to me probable, that it consists indeed in the defect of that matter, which should be supplied to the nerves for the exercise of the animal functions, but occasioned from the vitiated organization of the parts and vessels of the Brain, from whence a due secretion (which I have heretofore [Tr. de secretione animali] endeavoured to make probable to be here performed by a simple colature in the Cortical glandules) of the nervous liquor out of the blood cannot be made, but that, either from the forementioned distension of the sanguiferous vessels, the secretory ducts cannot readily admit the matter to be separated; the confusion of the mass, emergent upon such a congestion, prohibiting a regular secession; or else the grosser substance of the blood, not moved as 'twas wont, being brought to the beginnings of the nerves, must needs obstruct them, and so cause an immediate cessation of motion in all parts below, as well as, by disturbing the regular motion of the spirits in the Brain, hinder the exertion, not only of the Intellectual, but also sensitive faculties.  
For though Intellection (and possibly Sense) belong only to the Soul as such, which is a substance distinct in itself from the Body; yet the exercises of it, so long as the soul continues united to the body, cannot be had but by its mediation: our bodies being very fitly resembled to Hydraulick Engines, whose structure disposes them to exhibit a great number of various phaenomena, when filled with a due liquor, and set on work by a mover distinct from them (whether within or without 'tis not material) which, as they, whilst in order, very regularly perform all the motions their fabric directs to, so if they happen to be either accidentally broken or disordered in any part, or else the liquor they carry comes to be so gross as to obstruct them, or corrosive, or otherwise vitiated, as to make its way through them, must either undergo a total loss of their motion, or at least a very great disorder in the several performances that the organical design requires. Agreeably to which, the Blood appears to be the principal liquor for the motion of this curious engine of our body, as being universally and uncessantly carried through all parts of it. (Not to make a comparison betwixt this and the Nervous juice; which though it may be designed for more noble, and perhaps much more extensive proximate uses, than the gross mass of the blood, yet must be owned, on the account of its small quantity, and slow motion, to be not fit for this design, otherwise than to spiritualise, and give an instinct to that and the Heart that impels it, add that 'tis made out of the blood.) Now if through the fault of its pipes, the arteries and veins, it make its way out of them, it must of necessity extremely disaffect the parts in which this happens, especially when they are designed for the nobler sort of uses. Indeed Life, as well from arguments of Reason, as the Divine Oracles (which tho' they teach many things above, yet none against, Reason; and I conceive aught to be construed literally when the analogy of reason and nature countenances it, though many things in them are owned to be spoken according to men's common apprehensions; holy scripture being designed not to teach, Philo— but Theosophy) seems to consist originally, and therefore principally, in the motion of the Blood, its first indicia being from the punctum saliens; for which therefore so exquisite pipes are made to distribute it to all parts of the body, and return it back again to its first source for reiterated motions, and those so adapted to the secretory parts, for the separating of substances from it for several uses; that as all vital actions must needs be placidly performed whilst they are thus duly disposed, so if any of them happen to be broken or opened (at least in any considerable measure) whereby this vital stream gets forth of its boundaries, that due and regular motion thence ceasing, Life must too. But this must most effectually come to pass, if this disturbance of the motion of the blood chance to be in the Brain, where the Soul sits (by the consent of almost all) enthroned, and from whence she gives laws to all the Body: so that if this her Royal seat happen to be overwhelmed with such a deluge, and her intercourse with the rest of the body, which her Empire over it requires, intercepted, 'tis no wonder she leaves her province and mansion, thus become so unfit for her residence. But I must beg your pardon for these allegorical excursions, which yet the luxuriancy of the subject readily affords.  
This fault in the due Organization of the Brain consists, either in an Obstruction of the passages, or a Solution of the continuity; either of which may easily occasion any of the symptoms. For the former; 'tis impossible but that (since there is a necessity of a due proportion between the cavity of the vessels and the liquors, as well here, as in innumerable instances every where to be met with, to the performing of regular motions) if any obstruction happen, the Liquors must either move more sparingly than is requisite, or be congested there, or else the course of them must be diverted into other channels, and so nature's designation (to be discerned by the known effects) must be altered: from any of which occasions, as there must happen a defect of spirits to actuate the Brain and nerves, and that proportionally to the greatness of the obstruction; so if this happen suddenly, and be total, 'tis evident that there must follow both a total and sudden abolition of the animal functions. In the latter, the Blood, flowing out of its vessels, must, in so tender a part as the Brain, quickly overflow a great part of it, being urged on by the impulse from the heart; and then 'tis obvious that all the regular motions and secretions there, necessary to animality, must immediately be interrupted; the passages designed for carrying select substances being thus both enlarged and filled with heterogeneous and gross ones, which make up the much greatest part of the Blood. So that hence,  
Thirdly, What is called the Containing cause is easy to be collected, viz. some matter either discharged out of the sanguiferous vessels upon the substance of the Brain; or else, filling and distending them, and thence compressing the sides of the passages in it. This may either be, 1st, the Blood in its whole substance, whether good, or impure; since in either constitution it may, if either congested in too great quantity, or too impetuously moved, get out of its vessels, or else so distend them, as to produce the mentioned effect. Or, 2dly, some Viscouse matter, proceeding from the Serum become less spirituous, whose particles therefore are disposed to lay hold one of another, and so to grow clammy, and consequently unapt to pass along the usual tracts, but apt to stick in the laxer interstices between the arteries and veins in the habit of the Brain; to which more, being continually brought by the continual motion of the Blood, may by a likeness of substance, still associate itself, till it come to a congestion great enough to cause such an obstruction, as may at last hinder the circulation, or at least the separation of such substances from the Blood, as must actuate the Brain and nerves. From such a cause too Inflammations, which are some of the acutest, as well as the most frequent sort of distempers that assail us, often arise; and 'tis generally to be observed that in pleurisies, anginas, etc. the Blood is exceeding viscous; which quality in it disposing it to obstruct, must therefore, when that happens, cause a congestion all about, the Blood incessantly arietating against that place, and thence soon an inflammation. Or, 3dly, a greater collection than usual of the fluid Serum in the Blood, though not disposed to viscosity, but instead thereof grown too sharp, which thence may be very apt to make its way through the passages in the habit of the Brain, whose natural Make might keep out a less thin Serum, such as belongs to the Blood duly constituted but cannot this, in regard its particles are perhaps become less than the diameter of the pores of the vessels 'tis naturally carried into; or else these pores may come to be so dilated by means of the continual lancinations, that the resistance of their sides may soon come to be overpowered. Or, 4 thly, polypous concretions, (those infelicia aegri cordis germina, as Wepfer calls them) which have their construction from the fibrous parts of the Blood, whose Make being oblong and ramous, numbers of them may happen to associate in the heart too strictly, and being, when once thus associated, unapt to be dissolved, must make carneous concretions there; where being radicated, they may grow to a considerable bulk and length, and diffuse themselves all along the arteries to a great length: the manner of whose production the accurate Malpighius (de polypo cordis) has very curiously described. These Wepfer supposes may make an Apoplexy on a double account, viz. either entire, or broken. The former way, by being propagated from the heart up to the entrance of the Carotides and vertebral arteries into the skull, which vessels, being extensive before, let the Blood pass by these polypi up to the Brain before they reach those perforations of the skull; but when once they do that, the arteries being confined by the bones, through which they pass, must be totally stopped by them; and so the Blood being prohibited from coming to the Brain, an Apoplexy must according to him, follow. Which supposition indeed, if it could be demonstrated, would prove the greatest instance of his assertion, that Apoplexy may proceed from a denegation of Blood to the Brain. But, besides that 'tis hard to conceive all these four arteries should be stopped at once by this cause (which if they be not, the Blood coming by any one will be diffused by means of the Anastomoses all over the Brain, for the continuance at least of the animal actions, though perhaps in somewhat a lower degree) it seems moreover probable, that this should rather be ranked under the class of Cardiacal Syncopes, whose symptoms are very like those of an Apoplexy: and so many and large polypi, as must effect this, would in likelihood kill, by hindering the Circulation through the heart, before they could grow to the length and bigness requisite to cause this obstruction. But the other way by which he supposes an obstruction from them may come, is the breaking of them off being grown fracid; which happening, the course of the Blood must carry them on into those narrower passages; whereby it might be presumed there would follow such a sudden obstruction as must produce an irremediable Apoplexy, did not his instance of james Knoll evince the contrary; who, though the arteries in his Brain were full of them, yet had never any touch of an Apoplexy: unless we should suppose those were not true polypi, which, as I said, are generally of a carneous nature, and radicated in the heart, but only associations of viscous substances in the degenerated Blood, form in those places where he found them. But indeed it seems probable, that if any of these broken polypi get into the narrow passages of the arteries in the Brain, they may cause such a stop of the Blood there, that it not finding its usual way open, may, by the impetuosity of its motion, make itself a new one into the substance of the Brain.  
So that from any of these causes the Blood in its circulation passing (as I have said) irregularly through the Brain, may, if this part happen to be more than usually susceptible of an impression from it, either deflect into the lateral yielding recesses in its habit, or by reason of a partial obstruction of the vessels, distend them; since being impelled in the usual quantity, but deficiently transmitted, there must quickly follow such a congestion, that either a stagnation of it in the vessels must happen; or an exudation of some parts of it through the widened passages; or else, if the impulse prove to be more violent, a laceration of them; from whence comes an Extravasation, which will be continually increased from the continual impulse upon parts thus become unfit to resist the motion.  
But of these causes of Apoplexies, especially those which prove most fatal, the Effusion of Blood, mentioned, seems to be the most usual (though as I see not but the distemper may, as I said, proceed from only a Congestion, so possibly this may be that from which most recover that do at all, however by continuance it may prove as dangerous, as being the beginning of that by effusion, and a stop of the Blood even in the vessels for any considerable time necessarily kills) both from what appears upon dissection; not only Wepfers, before mentioned, but others, observations evincing it, and I myself happened to observe the same in the dissection of a very worthy Lady, the Lady Pakington, the relation whereof was published in the Philosophical Transactions, Num. 173. A. D. 1675. as also in regard it seems difficult to make out how, from a slow congestion, if viscous matter be the cause, or from an exudation of Serum, the diffusion whereof, though somewhat more speedy than in the supposition of viscosity, is yet comparatively slow to the sodainness of the invasion, much more from so very slow a congestion as must produce a fleshy substance as the polypus is (unless on the occasion of its dislodging, even now mentioned) all the Animal functions from a perfect exercise of them, as is most usually observable, should so instantaneously be destroyed. Whereas the effusion of the Blood out of its vessels may rationally yield an account of this defection with as great swiftness as can be imagined; the Blood as I said before, once got out of its channels being propelled, by means of the impulse from the heart, so as to diffuse itself immediately over the whole substance of the Brain, so far as the investing membrane will permit. And though only one Lobe of it chance to be disaffected, yet the commerce being broken off betwixt the spirits in this and the rest (it seeming probable, though, from the disproportion of our organs to discern those extremely small passages, not autoptically demonstrable, that there is a constant one by some small Meatus through the whole Brain) the action of the whole must cease; since 'tis observable that, for preforming regularly the actions which are the province of any organ, all the parts of that organ must be duly constituted; and therefore much more ought this to be observed in the Brain, whose action is so much more considerable and nice than any of the rest, as influencing the whole Body, as well as its texture is more curious, and substance more tender.  
The Fourth thing proposed to be considered was, the Disposition of the part, where the distemper is seated, to be affected; which having endeavoured to make out to be the Brain, we are to reflect that much of the invasion of the distemper (as was before insinuated) is owing to the vitiated organization of it, and not all to the perluent liquors. For if it be firm in its tone, and otherwise rightly constituted, there is reason to suppose it may, caeteris paribus, much resist morbific impressions; whereas if it have been before weakened, 'tis obvious 'twill easily yield to them. We see in Fevers that the Blood runs rapidly enough through it; and in an Anasarca, and cachectical habits, the Serum makes up much the greatest part of the Blood, which might therefore be presumed apt to overflow that tender part; so also 'tis observable, that the Blood many times appears extremely viscous, as in Pleurisies, Rheumatismes, etc. Yet in none of these cases ordinarily are the persons inclined to Apoplexies: so that though the irregularities of the liquors may sometimes occasion them without this predisposition oft he Brain, yet when it appears they invade more frequently than otherwise they use to do, there seems considerable reason, to suppose, that it deflects some way or other in its Organization from what is natural to it. This defect, I deny not may perhaps sometimes consist in too great a Closeness of its texture, whereby a partial obstruction of its vessels may be made by degrees, from the adhesion of some viscouse matter deposited by little and little by the circulating Blood about the capillary arteries, and so the Blood behind comes indeed only to be retarded here whilst no disturbance happens to it, but takes its course to some other region of the Body; but if it once come to be more than ordinarily exagitated, it may become so determined in its motion, as at last to flow impetuously hither too, but not being able to get through its usual channels must produce the effects, before suggested, of an irruption into the substance of the Brain: but yet ordinarily, I conceive, it depends upon too great Laxity of it; whereby, when any forcible impulse happens, it may too readily yield to it, and so be suddenly overwhelmed. This laxity may be considered to consist, not only in a greater inteneration of its substance than usual, and thence its easiness to yield to the force of the impelled Blood, to which in its due constitution it bears a proportion; but likewise in the greater openness of its pores than is natural, though the fibres that constitute it have their due degree of firmness, whereby it becomes capable of receiving other, and more bulky particles than usual, as is consequential upon that texture so depraved: which may possibly (as in too serous and acrimonious a dyscrasy of the Blood) proceed from the abrasion of some of the loser particles that constitute the habit of the part, by the perluent juice supplied by such Blood, and I suppose might be the case of the Lady before mentioned, who being endued with an extraordinary acumen, a great evidence of an exquisite constitution of the Brain, yet abounded with exceedingly sharp substances in her Blood or other liquors, as many, of her symptoms declared. Which pores likewise may acquire other figures than are proper for them; these concurring particularly to determine almost any of the Secretions, whether simple or mixed, that happen in our Bodies. So that when the Brain happens to have its Organization thus vitiated, and the other causes concur, an Apoplexy may in probability easily enough be produced.  
So that, to recapitulate, I conceive the part effected may either be the whole Brain, or any considerable part of it, and either the Cortical, or Medullar, but especially (or at lest first) the Cortical, from whence the disaffected matter is transmitted to the parts of it which lie deeper, where the animal spirits principally exert themselves; the Nature of the distemper to consist, in the sudden abolition of the due excrasie, and distribution of them thence; the immediate cause, most usually (when unavoidably fatal) an effusion of Blood out of its vessels upon the substance of the Brain, though I conceive a bare distension, of the arteries there may occasion it, as also may perhaps a congestion of viscous or serous matter when it comes to a considerable degree, and becomes freshly excited; or else Polypous concretions, or (if we can suppose it) any other obstructing matter deposited in it, may at last produce it; and the predisposition of the Brain to it, to consist, usually, in the more than ordinary laxity, or openness of it.  
These things premised I consider (to advance a little farther toward the solution of the Problem) that whatsoever, either 1 st. causes a congestion of Blood, or 2dly otherwise so indisposes it, that it cannot readily and duly circulate through its usual vessels in the Brain, or else 3dly disaffects the Brain, whether by weakening its tone, or altering the figures of its passages, or straightening them too much, may occasion Apoplexies: and the greater urgency or violence, of such antecedent causes may introduce a greater frequency of them than ordinary.  
As to the first; Besides common observation, 'tis obvious to any man's reason, that those who indulge themselves in full meals, but especially in copious drinking, and use not due exercise, may fall into them, especially if their natural constitution incline them to breed Blood plentifully; since so it must be heaped up in too great a proportion for the vessels, and thence may easily be supposed to make its way out of them, upon, even light occasions into the most yielding parts. Besides, persons given to these excesses do frequently, either voluntarily, or by the necessity of the irrigation made on the Brain, allow themselves likewise great liberty of sleeping, and so relax the Brain; whereupon the Blood flowing more plentifully in the usual posture of it, viz. lying along, may be presumed without great difficulty to get out of its vessels, distended on this occasion, into it. And it seems rather to be wondered at that no more fall into them, than that some do from this cause; since there are so obvious reasons of their production from the number of those who thus indulge themselves. But this seems no adequate reason of their greater frequency now than formerly, since these excesses have been of a much longer date, than to give occasion hence to justify the temperance of former ages comparatively to ours. Therefore,  
Secondly; as to the causes of those dyserafies of the Blood, from whence the immediate continent cause of Apoplexies flows, we must seek them from without us, since our Blood has its supplies so: and its motions, whether circular or intestine, are excited or retarded by abundance of outward, and the most of them inevitable (our shallow knowledge and foresight in choosing what is proper for us, and avoiding what is prejudicial, and the unmanagable bent of our inclinations to what gratifies us, especially considered) occasions. From which external causes likewise.  
Thirdly, the disposition of the Brain to fall into these distempers must proceed; these being as well disposed to act on the solid, as fluid, substances of our Bodies, as they find them fit to receive their impressions.  
The external occasions therefore of our disorders are generally deduced from some or other of the six Nonnaturals, so called, viz. Air, Meats and Drinks, Motion and Rest, Sleep and Waking, substances excreted or retained; and the passions of the mind: any of which, if inordinate, may produce such diseases as the Body, upon some peculiar predisposition, is subject to.  
'Tis besides my subject to dilate on them particularly, especially as they contribute to produce the gross of diseases; neither do I think the five latter so very applicable to my present theme, as to detain me. But the first seeming the most usual and efficacious, as to the production of all, or the greatest part of other distempers, since 'tis so generally influential and unavoidable, so of this, I am obliged to take some notice of it. For we may in a great measure correct irregularities in the rest; but not so in this, without which we cannot live many moments; neither is it in our power to correct its disorders, if any thing considerable, since it diffuses itself every where; and must therefore, if vitiated, be the cause of general distempers, and more especially seems to have a very prevailing energy to introduce that under consideration.  
Its disorders are generally reduced to two heads, viz. either excesses in (one at least of) the First qualities, Heat, Cold, Moisture, or Dryness; or else Malignity in it, unaccountable for from them (whatever it satisfactorily be from any other vulgar notions) which may be of very different kinds, and so produce distempers, different as to their symptoms, yet of that general denomination. These have been so copiously and learnedly treated of by many great Authors, that 'twere very impertinent in itself, as well as unfit for the brevity of a letter, to expatiate on them: but particularly the Doctrine of Malignity seems too abstruse to be discoursed of in few words; only (if it be not a solecism to pretend to judge of things of which we can assign so little reason) it seems best adjusted to give an account of diseases that generally invade, and where indeed surprising symptoms, whose reasons cannot be assigned from known hypotheses, happen, as in some Epidemical fevers, the Plague etc. For it seems agreeable to reason, that it must be somewhat more than what is deducible from the first qualities, as well as very active, that must so affect multitudes of people of different constitutions, and of whom many have no evident predisposition to sickness, with so extraordinary indispositions, and that at times when the Air is free from excesses in any of the first qualities, (or indeed any of the rest of the sensible ones:) and 'tis acknowledged by all, how differently soever they explicate the matter, that these epidemical miasmes are so.  
But to give an account of the production of the present distemper, we have no need to have recourse to this abstruser cause. For, first, this can hardly be reckoned among Epidemical distempers, however more frequent than formerly; since at all but few, comparatively to those who are with other distempers, are assaulted with this, and those not in one region, but here and there in far distant places, at all times of the Year, and at all seasons, whether of excessive Heat, Cold, Moisture, or Dryness; (though, as I shall by and by observe, it took its rise from one of them.) Secondly, 'twas never observed, nor thought, contagious, as most Epidemical diseases that depend upon Malignity, are; those subtle steams that occasion them being, as very diffusive, so also determinately fermentative to the production of like substances in the Bodies they enter into; which when emitted, and then received by others which have a predisposition (as most have; a small one being sufficient in so heterogeneous Bodies as ours are, and where the substances that compose them are so lax, and in such an agitation) to be by them acted on, must affect them in the same manner. Thirdly, there seems nothing in the symptoms but what is constantly observable in almost all assaulted with it, and agreeable to the general history of it; whereas those called epidemical have generally something anomalous in the symptoms, when ever they so invade, from what has been observed in those of the same denomination at other times. And fourthly it seems accountable enough for, from the consideration of those more obvious qualities of the Air. So that I conceive 'tis rather to be reckoned among the Sporadical diseases, so called by Physicians; and to proceed from some, or one of these (modifications of the Air, which we call) first qualities. But from which of them, 'tis requisite we inquire.  
To consider first the Passive qualities of the Air, Dryness and Moisture; it may perhaps seem probable that they may, in order to produce this, as well as some other distempers, indispose the Brain; the former by hardening the tone of the sanguiferous vessels in general, and consequently contracting their tubes, and so causing an acceleration of the motion of the Blood through them (which must, if propelled with the same force at its original, run more swiftly through vessels when thus straitened, than whilst having their usual dilatation:) whereby it may be presumed, that when cast forth of the arteries into the interstices between them and the veins at their extremities, it may make its way into the more yielding substances it is any where to pass through: and the Brain being confessedly more so, than any other part of the Body, is therefore most likely to be affected on such occasion: the latter (which is countenanced by the great Hypocrates, Sect. 3. Aph. 16.) by intenerating the Brain so much beyond its usual constitution, that it may thence become more than naturally susceptible of the always briskly circulating Blood. Next; as to the most efficacious of the Active ones, Heat; it may perhaps be urged that the Blood, though otherwise well enough constituted, being much heated and rarifyed by that excess of the Ambient, might be inclined to make its way out of the vessels, in the Brain especially, on the account of its forementioned tenderness.  
But, besides that experience warrants none of these suppositions, perhaps it can hardly be made out, 1st, That so great a dryness, as must effect this, can be introduced into our Bodies, which are continually irrigated, not only by the circulating Blood, but other secondary liquors; 2dly, That a great excess of moisture in the Air should produce Apoplexies, unless those more rare ones (as I suppose they are) from the Serum, and that generally after other distempers which have weakened the crasis of the Blood, as well as the tone of the Brain; since such a dyscrasy impressed on the Blood seems to make it more torpid by clogging the spirits in it, and so less apt to inundations, and besides relaxes the vessels, as well as the substance, of the Brain, and so favours its ready passage along them; and, 3dly, That the excess of outward heat should cause this eruption; since by it the solid parts may be as well presumed to be invigorated to resist, as the Blood excited to attempt it; besides that the transpiration, that is occasioned by this heat, may sufficiently compensate for the accelerated motion of the Blood, its quantity (which may in that case be principally dangerous) being thence diminished.  
It remains then to attribute this frequency of Apoplexies to the Coldness of the Air, as the most adequate occasion; which when it happens to be intensely so, may, I conceive, be made out to give a probable reason of it.  
That Cold is a great enemy to the Brain, is both the general sense, and confirmed by the authority of Hypocrates, Sect. 5. Aph. 18. and all Physicians since: and therefore we may possibly infer that the great Architect fenced this part with so strong a wall, scarce more to protect it from other injuries than this, to which 'twould otherwise be exposed. But how Cold affects it so injuriously may require a little explication.  
In order to it, give me leave, Sir, to consider (without pretending to discuss it so minutely, as men of more Philosophical heads, and better accomplished in such speculations, might) the nature of Cold, as being requisite to be known in some measure to the understanding its relative effects. Which attempt indeed might appear very presumptuous, after that the exquisite Mr. boil has not thought fit to determine in the matter, but that you may perhaps find that the short deductions I make, however unartificially, are either taken from, or, I conceive, reducible to what he has delivered; and so far from being positively asserted, that they are only submitted to the censure of your, and others, better judgements. To which purpose three or four general considerations seem not unfit, so far as belongs to our present disquisition, to be taken notice of, to give an account of its manner of affecting us.  
In the first place than it may be considered, that though neither Cold nor Heat nor any of the rest of the sensible qualities have any real Being, but only in relation to our perception; insomuch that were there no sensitive Being's there could be no such things; yet they must be founded on something that does really exist, as all accidents besides are. So that though they cannot be reckoned amongst the general affections of matter, as motion (though they depend upon it) or its contrary, Rest, Bulk, Figure, etc. are, which would still be where matter is, tho' there were no sensitive Being's, yet are consequent upon it, but determined by these and associated to somewhat that has perception.  
Secondly, That 'tis evident our sensories are affected by Cold, that is, have some impression made on them. Now nothing can affect but by approaching to that which it does so affect, and to approach requiring motion it must follow that motion must go to constitute the nature of Cold. Which though it may seem not so evident, since Cold is reckoned contrary to Heat; and this consisting obviously in motion it may be urged, that should in Rest: Yet it may be returned, that tho' it be necessarily to be inferred, there is motion where there is Heat, yet not always that there is Heat where motion: so that 'tis not motion simply, but considered with some adjunct, viz. motion in such or such a degree, and with relation to sensitive Being's that constitutes Heat; and consequently that 'tis not to be inferred that Cold consists in absolute Rest, because contrary to Heat, but in a different degree of motion (though other mechanical affections must concur to determine it) which recedes on one hand from a middle degree of it in our sensory, as that which makes Heat does on the other. Which too may be evinced from hence, that each of them having a great latitude of degrees must be founded in what admits of degrees, which motion does, but Rest not.  
Thirdly, that motion here being not to be considered abstractedly, but together with the subjects of it, and as occasioned by, and produced in some Bodies; we may take notice, that as 'tis evident the Bodies without us, which excite our sensation, are moved, so our organs, which are designed to receive the impressions of these extraneous objects, and transmit them to the Soul, can hardly be presumed to do it (any more indeed than prove a fit mansion for her) without having their particles (whether consistent or fluid; for both are necessary to their construction) in motion: and not only so, but endued with a determinate degree of it. This degree ought not to be violent: for so the constituting particles neither could be brought into such a frame as we find they are, nor persist in it; but they (especially the most subtle, which are the Souls immediate instruments in the organ) would soon undergo new textures, or be dissipated. As on the other hand it must not be very languid, since in that case they being in great numbers, and some touching still in their motion upon others which have a different determination, would soon be entangled in one another, or otherwise stopped. But it must be such a middle one, as may keep up a due crasis in both the fluid and consistent substances that make up the organ, for the performing the functions appointed.  
Fourthly, that these motions (considered as I said in their subject) thus regulated, being congenial to us, seem not properly objects of our perception (at least are not taken notice of) since 'tis by means of them that the Soul receives those impressions that cause a perception of others, but rather instruments of transmission of those others from without, which recede from these degrees, or are otherwise circumstantiated: tho' indeed even these, when, becoming either too quick or too slow, they defect from their due proportion, may, by affecting the Soul differently from what they use to do, so excite her, as that she may take notice of them too, as well as those of exterior objects which thus solicit them.  
Fifthly, that therefore these mean motions, being what belong to the organs duly constituted, are the standard from whence we are to take our measures of all others, so that when any objects from without come against, and so affect, our sensories with a greater degree of motion, than what naturally belongs to them, we form one kind of notion of them; when with a lesser degree, a very different one, and give them likewise denominations according to that degree of motion with which they act upon our sensory.  
From the consideration of these particulars, we may, I conceive, deduce, that the nature of Cold consists in a check (though not a total stop) of that degree of motion, which belongs naturally to the parts of, and fluid substances in, those of our sensories which concern the sense of Touching, duly constituted; as, on the contrary, Heat (without some reflection on which, Cold can hardly be understood) in an acceleration of such their motions. Which differences being, by means of these organs transmitted to the Soul, and so affecting her, she, forming a comparison between them, denominates one Heat, and the other Cold.  
But though motion must have the first consideration in producing this effect upon us, yet 'tis farther to be noted, that the Bulk, and Figures, both of the Bodies that cause this check, and those upon which 'tis impressed, must concur to it: it being evident, that not only some are themselves more fit and easy to be moved than others, according as they are bigger or less, of this or that figure, but also to accelerate, or retard, the motions of others that impinge against them.  
As to acceleration, wherein Heat consists, minute Bodies, of almost any figures that are irregular, if they are not apt to cohere, may occasion that though some more than others; especially those that are most angular: since with their angles striking against those among which they move, they must be presumed to exert a proportionally greater force, than blunt or glabrous ones can, which on that score are easy to be distorted. But as to retardation which makes the nature of Cold (that we may restrain our discourse to that) it may be occasioned on several accounts. For, first, either the affecting Bodies may, by a correspondency of their sides, so apply themselves to those to which they come, that, transferring their surplusage of motion to them, they may adhere to them, and with them constitute bigger masses, and acquire other figures than before they had: Or, Secondly, by altering the due contexture of the vessels (which is necessary to regular motions) they may thence occasion a stop of the substances, which used to be carried in them; and so, though they are otherwise disposed to accelerate motion on the account of their figures, as I said before, yet thus accidentally they come to retard it: Or, Thirdly, if they happen to be of such a figure and texture as to be flexible, and thereby to wrap themselves about those they occur to, they may, by thus inviscating them, hinder their motion: Or, Fourthly, (and which may possibly, in the present case, be the most effectual means of occasioning this check) they may so interpose themselves between the moved particles in the organ, as to intercept their former motions; whereby also they fill the spaces necessary for continuing those motions. This seems most agreeably to be done by Conical ones, which by their angle are fitted to enter, but being blunt and bigger at the other extremity, must, when they come into porosities, which are a little straiter than that necessarily fix there; and both the more abate the motion of the forementioned agitated matter, and also be more firmly impacted in the parts unto which they thus arrive, by their contraction, upon the score of the lancination occasioned by the sharp angle of these particles first entering: the solid parts, that are sensile, being all the Body over contractile, as being, I suppose, nothing else, but either propagations of nerves or the roots of them. And when it happens that many such conical substances come to act at once upon the organs, the effect must be the more considerable.  
But perhaps, Sir, you may think these speculations too nice and general; and indeed impertinent to the present consideration, since they are not our senses that are in Apoplexies primarily affected; those persons that are violently seized losing, immediately upon the stroke, the use of them; but only influentially from the Brain, which itself is thought to be void of sense actually (which supposition yet may perhaps be liable to some exceptions) though the source of it to all the Body beside: And therefore when they invade more gradually, and those that are affected are conscious of great pain in the head, it may be supposed that the morbific matter affects the membranes of the Brain, as well as the substance, and so causes that symptom. So that if the predisposition to the disease be from Cold affecting a part of our Body not sensible, you may ask to what purpose all this notion of our perception is introduced? However give me leave to say, that since Cold would not properly be Cold, as I have urged, without perception; which though it produce all the effects, it does on Bodies not endued with sense, on a purely mechanical account, viz. from schematismes of matter in motion, determined by the fitness of some to act on others, according as they apple to one another; yet as it relates to us, who are endued with sense, and to whom it belongs to define things cannot be well understood without reflection on that; it seems not altogether alien to our purpose to state it in that latitude, since without such a reflection we cannot have a notion of it; and therefore not explicate its positive nature, and what produces it. And indeed whether these speculations are altogether superfluous, may be judged from taking, first, some short view of the nature of the Air, so far as concerns its aptitude to act on Bodies conversant in it, particularly ours, it being the Medium to convey the influence of exterior (when not immediately contiguous) objects, or at least necessarily concurring to make considerable impressions on us who, 'tis known, cannot live many minutes without it, especially in relation to it when deflecting toward Cold: and secondly, its manner of affecting injuriously our Bodies, particularly the Brain, upon the account of the forementioned mechanical affections.  
And first, as to the Nature of the Air; Though, generally speaking, we call so all that vast congeries of corpuscles wherein we breath, which is made up of all sorts of particles from the earth and water, and steames raised from complex bodies in or upon them, yet more properly (according to the Philosophy of the Age, which acknowledges the Excellent Mr. Boil its chief refiner) 'tis supposed to consist in the greatest measure of springing particles, viz. oblong, and considerably rigid ones, though very tough, and thence apt enough to be bend by a great pressure, but yet unapt to lose force of restitution toward a direct line (which seems most natural) when that pressure is taken off; and which they, whilst thus bend, are continually (from the action of the materia subtilis according to Descartes) endeavouring at: From which tendency to restitution there must be variety of motions impressed on all bodies conversant in it, according as they are disposed to receive its action. But yet among these 'tis supposed there are a considerable number of others, called Nitrous, whose make may possibly be that a little before described, viz. Chnicall or Pyramidal (for I suppose either may solve the Phaenomena, which require only acuminated particles whose other extreme should be bulky) and from the mechanical effects may very much justify that most ingenious notion of Descartes, who supposes Niter to have conical figures. For on the account of these the particles of it may, like wedges, easily intrude themselves into the Interstices of any bodies they happen to be carried against, and, if these be yielding enough, make themselves more and more way amongst them, and therefore may intercept the motion of some as well as very differingly determine that of others of the fluid substances contained in them; since none, of what texture soever, can be presumed to elude the action of such kind of bodies. Which supposition concerning their fabric appears to me the more probable, because fitted to explicate the matter mechanically, that is, intelligibly. For I conceive all the world of bodies, and their actions, is pure Mechanism; and therefore 'tis requisite all explications relating to them, designed to inform, and not to puzzle, should be founded on principles of that kind.  
And indeed though it be impossible to make so full a discovery of the small constituting particles of this as well as any other concretes, that we may have ground to dogmatise on them, they being much below the perception of our sight, though assisted even by the best Microscopes; yet since few of them act to our perception, singly, but to do it must be associated into somewhat bulky concretions; which may possibly be allowed to make deductions from the observation of such, when we find them to convene in a familiar and natural way. Consequentially whereupon we may take notice (for the confirmation of Descartes' notion) of what the curious Mr. Leewenhoeck observed with his exquisite Microscope, as to the concretion of Niter, dissolved in water, upon evaporation (to be met with, Philosoph. Transact. Numb. 173. jul. 26. 1685.) As, saith he, The water in any place began to be evaporated I found many figures whose basis was square, and rising to a Pyramid. And though there were other figures exhibited, yet it may very easily happen that upon a coalition of a multitude of these extremely small particles, in so confused a manner as must be upon an evaporation (besides that many of other kinds may associate with them) variety of figures may well emerge from those so convening, though the principal have the forementioned tendency. And besides, though the figures of minute ones might not be Pyramidal, yet it may be such as to fit them, from their congruity to one another, to associate strictly into this; it being by many Chemical instances of the acting of bodies, salts particularly, on one another, obvious that these of very different makes do, upon their collisions, when diluted in a fluid, unite into concretes very strict that have little or no cognation in their figures to either of those singly that went primarily to constitute them: So that when freed from their diluting moisture, which brought them together, and then pressed upon by the strokes of the Elastical particles of the Air, they may possibly come to cohere so strictly (supposing their sides smooth and flat, as it seems probable they are even from the obvious figure of the concrete; and is deducible from that effect of the Air in the much noted instance of two flat marbles) and be so hardened, as to be fit to act (their acuminated figure considered) almost equally vigorously, as if they had been primitive ones, on Bodies not of the very closest texture. Nay since they are designed to act on such which have no very compact texture, for the most part; it seems congruous that theirs should be such likewise, to bear a proportion to them, which perfect solids of those bulks and figures, that were primitives, would not.  
'Tis true, Descartes assigns that figure to the particles of Niter to explicate the manner of its Accension, which produces Heat, when so modified; and that perhaps more violent than any other Bodies do. But as 'tis sufficiently known that in many instances it much refrigerateth; and there must be a natural reason for one effect as well as the other; I conceive that of both, however opposite, may genuinely enough be deduced from that fabric, according to different modifications; and therefore may be presumed to establish the notion of that kind of figures. For in order to produce the latter they, by entering with their apex, as I just now said, into the porosities of the organs (which they must do, if the point be very sharp, though carried to them with ever so slow a motion) and still piercing more deeply by degrees, may placidly enough retard the motion of the substances therein agitated. And indeed to effect this a comparatively slow motion seems necessary; such as agrees not only to the forementioned notion of Cold, but also both to the Air in general, which is placed in a boundless expansion, and therefore being not straitened must move calmly enough when not forcibly impelled; and especially to these Nitrous particles, which being dissociated by others of different kinds one from another, and having ordinarily there no violent impulse, must, on the account of their make, move leisurely when carried with the whole course of the mass of Air; and the rather, since the resistance, which their concomitant substances make against the thicker extremity of them, must much retard their motion. Withal, if it happen that these pointed particles enter into the passages of those sensible Bodies, they may be presumed so to strike against some of the fibres that constitute them, that they must from thence irritate them to contract themselves, and so the motion of the fluid substances in them must be effectually checked. But as for the production of Heat, another modification of them must be assigned, viz. a very brisk agitation from some external occasion; which happening, the apex, being more easily agitated than the basis, must necessarily describe a circle about it, which by reason of its greater bulk cannot be so easily moved out of its place, but only gyrate about its proper centre according to the direction of its cone; and by so doing the cone must needs strike very violently against such Bodies it meets in its way; whence a sense of Heat to sensible Bodies must necessarily proceed, in regard the force of this agitation must be supposed to be greater than that of the moved particles in the organ: which too must be raised to a much more considerable degree, when great numbers of these particles conspire to the like motion; especially if minute accensible substances of other kinds are interspersed among them, which, both from their own disposition to be so agitated, and their disterminating a little these nitrous ones, whereby they may have room to begin their gyration, may promote this accension; as in the too fatally known experiment of Gunpowder. I must indeed acknowledge that the angles at the basis of these corpuscles, if they be Pyramidal, according to Mr. Leewenhoeck's observation, may hinder the gyration, Descartes supposes, in some degree: but 'tis easy enough to conceive, that, as well here, as for the making his globuli aetherei, these angles, by the very brisk motion the corpuscles are put into may presently be ground off, and so they fitted for this gyration; and this much more easily than in that instance: because those primitive particles must be supposed to have been tightly solid, whereas these two have been coagmentated of some formerly divided, and only now cohering from the forementioned correspondency of their sides.  
So that the difference seems to consist in this, that to produce Cold 'tis requisite that these nitrous particles should both move singly and placidly, and also insinuate themselves amongst such substances as may confine them, being once entered, on every side, and so hinder the above mentioned gyration: Whereas to engender Heat 'tis necessary that they should be, both in greater numbers, be briskly agitated, and generally move in a sufficiently yielding medium, and at only such a distance from one another, as that in their gyration they may beat off one another with their points; from whence the motions of others among which they move must needs be considerably increased; and withal they either previously require, or, if the force of the agitation be the greater, make in almost ever so close a room a considerable space for themselves to move in.  
But perhaps an objection may be raised against what I intimated a little before concerning the ordinary motion of the Nitrous, particles in the Air, which I suppose to be carried with their Cones forwards: For it may be urged, that, being very confusedly moved, and amongst fluid substances, sometimes the Basis, and sometimes the sides, may in such an agitation be as well carried so as the Apex, and then the consequences of their insinuation, which I deduce, cannot have place; the assigned figure being that which fits them to produce the effect. To which I return, first that though some may in their motions, when brisk, so apple to Bodies as is objected; yet there being greater numbers, than ordinary, in Frosty Seasons floating in the Air, 'tis probable that some, at least, of them will be carried as I suppose. But secondly, it seems to me probable, that being moved placidly enough (according to the supposition) their natural tendency must be with their points forwards: For in that posture they both find less resistance amongst those against which they move, and are supported in their motion by other lateral ones crowding upon them; and also those which are moved behind them impel them the more easily forward when they impinge against a flat surface (as the Basis is supposed generally to have, or at lest what approaches toward it) than against that of any other figure; and therefore determine them to carry their Apex as I said.  
But whatever their make be, 'tis both generally supposed, and seems to me very probable, that without these the Air could hardly be vital. For some substances that are fit to be agitated, but unapt to cohere, seem requisite to be intermixed amongst the various parts of our Blood, and other liquors, which may, by their vibrations, whether occasioned from without, or from the motion of our spirits, keep them from too close complications, which that many of them are much subject to is very obvious: and these I take to be those usually called Nitrous.  
But though these in the Air, may have a very great, if not the principal, influence, on any Bodies they can enter into to produce many effects, but particularly, on sensile ones, Cold; yet both the Elastical particles and also the steams before mentioned, with which the Atmosphere is considerably stored, must much concur to any of them; these on the account of their great variety and irregularity, whereby they are apt to be determined to very differing motion, and thence to solicit the particles of the Bodies they act on to the like, for the Nitrous ones to enter; and those by their expansiveness enlarging the passages for them. So that when the Air from any occasion happens to abound more than ordinarily with Niter, the assigned effect of it may be presumed easily to be produced, and especially on our Bodies, which being of a contexture tender and yielding enough, must be injuriously affected, if either the motions, or other disposition of its particles prove to be disproportionate to the parts of them, or substances contained in them.  
Therefore to inquire, Secondly, how our Bodies, but particularly the Brain, come to be thus injuriously affected from hence, we may take notice that the Air (with the substances it carries in it) exerts it influence partly on the liquors, and partly on the solid parts.  
First, for the liquors; we may consider briefly how it comes to be admitted into, and being so, after what manner it acts upon, first the Blood, and then the nervous juice (to omit the rest of them, as little conducing to the present speculation) and this as well amicably as noxiously.  
First, As to the Blood (which is most considerable as to quantity and supplies the matter to the nervous and the rest of the juices) we may take notice, that though the Air may even by contact affect it in the surface of our Bodies, as considerably pressing on us, and so perhaps arrest or variously determine its motion in some degree, yet it must principally do this by being admitted into it. This admission seems obvious; since, 1st, living in it, we cannot take any, either meats or drinks, but some Air will be admixed, and so be conveyed into our Blood with them. Besides, 2dly, it seems not improbable (though it have undergone some contest) that some of the finer parts of it may be admitted, in inspiration, farther than barely the cavities of the bronchia, since it must be owned there are vessels from the little glandules dispersed throughout them, which transmit from the Blood there: and whether those vessels may not receive something (tho' not so much) into them upon inspiration, as well as cast forth by expiration, may deserve to be considered, since the Air comes into the Lungs with some violence; and they, being placed in so warm a situation, may (besides the distension upon inspiration) be presumed to be as well lax enough to admit a subtle substance as eject a gross one: and it seems not altogether improbable that nature might design this reciprocation of motion for that end partly. But withal, 3dly, the pores every where in the skin seem well enough adjusted to admit somewhat from the Air, as well as convey forth those very gross impurities, which many times, if not very usually, pass forth without any trouble. And if it be objected that the transpiration continually proceeding from within must hinder any admission from without by the same vessels (which notion heretofore seemed to me to have great weight, as well in relation to these, as most other vessels, and liquors in the Body, though, upon farther thoughts, it requires some limitations, which belong not to this place to be laid down) it may be replied, that this transpiration, though it should be supposed continual, is not in the same tenor still; so that when it proceeds minutely, there may be an admission perhaps from without, between the particles of this gross and slowly moved matters in vessels patulous enough; when we consider both the great pressure of the Almosphere, which may easily enough be presumed on that score to intrude some particles of the Air between them to fill up the spaces left by the exhaling vapours; and also the cessation in some degree of the extrusive motion, whether proceeding from the expansiveness of the evaporating matter or the too much contraction of the parts; both which remitting, the resistance is less, and the room more, for the admission of those. Being thus admitted, 'tis obvious to deduce, from what was intimated before, how it ordinarily operates on the Blood, viz. that partly by the insinuation of its elastical and other irregular particles among the parts of it, partly the interposition as well as lancination of the nitrous, the ramous, and other grosser, being kept in a continual agitation, do both undergo due comminutions, and also are hindered from too closely adhering, and thence as well from stagnating in the wider vessels, as obstructing the capillaries and interstices between the arteries and veins. But such an agitation being necessary to it for the keeping up its vital crasis, it may easily be inferred, that if such Air be admitted as shall overmuch check this agitation, the crasis of it must come to be much altered, and those parts which were before dissociated by the briskness of their motion must, being considerably ramous, lay hold on one another, and so either become grumous, or create a viscosity in it, which, once begun, is not soon, nor easily, corrected; these particles clasping one another too firmly to be quickly unlocked by the permeating spirits; whose activity likewise these viscous substances are apt to elude by their lubricity, thence obliging them to slip by them; or else inviscating them.  
Secondly, As to the nervous juice; it being made out of the Blood, must therefore, in some degree, undergo impressions analogous to what are made upon this from substances admixed with it; whether we consider it in its due, or depraved, state: since it may be easily imagined that some of the admitted substances of the Air, before mentioned, may be deposited into the nerves at their original, together with the true matter of that juice: and besides if the Blood in general be once become viscous (from whatsoever cause) 'tis scarce possible, but that some part of such a matter must in the act of secretion pass into the nerves: so that the Air, in some constitutions of it, much disposing to viscosity, its influence therefore must be interpreted to be partly on this juice at such times. But moreover, I see no reason but some particles of it may when more than ordinarily abounding with such substances as are subtle and active, even through the pores be admitted into this liquor; our Bodies being every where permeable to subtle substances; since I conceive, they in a due proportion are necessary even to the due spiritualization of this juice; and therefore, for its excitation towards that may require to be admitted, partly, a nearer way than that roundabout one of the chyle.  
But, Secondly, The Air's influence must be acknowledged to be very great on the solid parts likewise; as both immediately touching upon some of them, and also, by reason of their firmness, being longer retained by them, when once admitted into their porosities (which, by the mediation of the Blood, besides the other ways mentioned, which are applicable to these as well as the liquors, 'tis easy to imagine its particles may) than in those fluid substances. So that in the forementioned suggestion of its superabounding with noxious substances, they must be much disposed to be affected by it. And indeed there seem to be none, even of the most consistent parts of our Bodies, but are pervious enough to, and consequently apt to be acted on by, such penetrating substances.  
But among them all none seem so liable to receive impressions from them as the Brain, on the account of its tender constitution. For, tho' Nature hath placed so strong fences about it, that perhaps 'twill hardly be admitted that the Coldness of the Ambient can greatly prejudice through them; yet that it may, by the mediation of the Blood passing through it, is, I suppose easy enough to be allowed from what has been said. But besides, there seem two or three other ways, by which, in such a constitution of the season, it may be injured; viz. First, By the Air's affecting the mammillary processes, as it passes briskly by them upon inspiration: which being considerably large nerves must (besides the consideration of the impetuosity of the Air's motion in that circumstance) be acted on by considerable numbers of its particles at once, and so undergo a strong impression, which may easily enough be conceived to be propagated to the Brain; partly, by disturbing their regular tonic motion, which must, from their tensity, be continued up to their original; partly, by the ingress of too many of the lancinating particles of it into them; which besides the fixing, or dissipating, the animal spirits (which I conceive to be much of the nature of volatill salts) may disorder the tone of these nerves first, and then (by the continuance of the impulse of those behind, which have the same ground to attempt an entrance) that of the Brain itself; which, being more tender than the nerves, must therefore, when the cause of the disaffection reaches it, be proportionally injured. A second way I conceive is at the ears, whose outer cavity going deep seems to be, in part, contrived for warming the Air, that it may not by its Coldness disaffect those tightly sensible auditory nerves and the membranes, upon whose due tone and tensity as the sense of hearing seems mainly to depend, so must it be much impaired if so unusual impressions are made upon it by intensely Cold Air, and besides those nerves being thence so disaffected must by their contractions convey the like motions up to the Brain, and so disturb and weaken it. And I formerly knew a very Learned person, who had a total and irremediable deafness, that was caused, as he told me, by a journey taken in a very keen frost over the Mountains in Wales: to which I remember not whether any Apoplectic distemper succeeded, but the instance at least evidences the great effect of intense Cold upon the nerves, which had it lasted long, 'tis to me probable that by being propagated up to the Brain it might have produced either that or other nerval distempers. Another way, whereby I conceive the Cold Air may be injurious to the Brain, is at the extremities of the nerves in all parts of the skin, which having (as must be owned I presume) apertures there, may possibly admit some such subtle and lancinating substances, as I have supposed to be constantly, but in frosty seasons more copiously, carried in the Air; and being once admitted may, on the same ground as I have urged in relation to the olfactory Nerves by consecution come to affect the Brain itself: But though their tracts are very long and small, and so there cannot be a proportionable influence, as in those; yet their great numbers, and the consideration that they are on every side pressed upon by the Air, may perhaps be thought to Compensate for that defect.  
But this pressure of the Air on the surface of our Bodies (which I distinguish from that on the olfactory nerves on this consideration, that in one case 'tis uniform, depending only on the weight of the Atmosphere, or such general motions in it, as make it act uniformly on all parts of the surface of them, which by their make, and private motions, determine it not otherwise; in the other, some part of it is moved with a greater violence, from the dilatation of the parts designed for Respiration; whose cavity therefore being to be filled in proportion to that dilatation, it must happen that that portion of Air that does it must have brisker agitation than the rest of its mass, and make impressions accordingly) this pressure, I say, may prove chiefly injurious to the Brain by its acting on the Nerves in the Ears: Because they, being terminated at a cavity which is still kept warmer than the rest, by the steames continually exuding from every side of it and for some time somewhat detained, there must therefore be more open, and consequently more liable to injuries if an extraordinary occasion happen, such as I am instancing in, to make an impression on them. And this must happen rather to tender Bodies, and those who accustom themselves to keep much within doors, than to the more robust, whose employments expose them much to the Air at all seasons, both on the score of the comparative flaccidity of all parts in them, and the defect of a due digestion in their blood and other liquors through want of due exercise, which must dispose them to be put into confusion when violent causes come to excite it; and experience shows that such persons of all others are most obnoxious to the alterations of the Air.  
So that the manner of this action seems to consist in the penetration made by the Nitrous particles (principally) of the Air upon the Fibres of the Brain (for that as well as all other solid parts must consist of Fibres) which thereby undergo some, however small, solution of continuity; and either the little cavities of those Fibres (for I think the Aeconomy of our Bodies can hardly be mechanically made out without supposing them all to be Vessels, though our sensories cannot determine it) become straitened, or their sides perforated; on the account of either of which, they cannot duly either receive, or retain, and consequently not regularly transmit, the substances destined to each part which is to be respectively supplied by them. In that continuity, due confirmation, & repletion of them, I suppose the Tone of the parts to consist: and therefore when any thing perverts any of these requisites to it, as in our present case, all the consequences, emergent from the impulse of the blood or other liquors disturbed in their motion, may be expected.  
Now such an Atony happening to be in so very tender a part as the Brain, cannot therefore easily be rectified, but may continue much longer, than if it happen to other parts whose Fibres being stronger, and functions fewer, must on both scores (caeteris paribus) sooner and more easily return to their natural constitution. And not only the reason of the thing, but daily experience, shows it; that whereas most other parts of our Bodies, having once received any injurious impression, as by falls blows, etc. do after fit remedies used, return to their due tone quickly, the cause once removed; the Brain on the contrary long retains its weakness if once injured, though for the present relieved in some degree: as, for instance those that have had an Apoplectic fit once, do many times, on whatsoever light occasion either find a return of it, or at least undergo a considerable weakness of their intellectual faculties, not to be corrected but by a long and constant regularity, if it be at all: and the like is observable concerning those who have been seized by Vertiginous and Hypochondriacal distempers (which I take to be properly Nerval, and to spring from the Brain, or its liquor, disaffected) from which few happen to be perfectly freed: their imagination indeed, being disturbed, disposing them to be too immorigerous.  
So that I conceive it may be inferred, that if the Ambient Air come to have a great degree of Coldness, especially if it continue long, both the forementioned disposition of the Blood to supply matter for Apoplexies must be introduced, and also such a debility may be impressed on the tone of the Brain, that they may much more readily invade, if the ordinary (though at other times innoxious, for the most part at least) occasions happen to bring these dispositions to effect.  
Now 'tis known that the Winter of the year 1683, (from which I date my Aera of this frequency of Apoplexies) was so intensely cold, and that cold of so long continuance, that no man's memory living could supply him with a parallel year; and there was no need to repair to the Northern Region to make experiments of freezing spirituous liquors in order to find out the extent of this effect of it: since which time it may be observed that this distemper has been so rife.  
But since 'tis requisite the Assertion should be established as much as possible by due observations, it came into my thoughts to examine the London Bills of Mortality; which may be presumed to be a standard for all the Kingdom, as well as all other places where the same constitution of the Air has happened. And though it may be urged, that the accounts of diseases in them are taken by persons who are not Judges of those things; yet many diseases carrying, by their obvious symptoms, such evidences of their nature, that 'tis almost impossible to mistake them, and above all, Apoplexies, as before was suggested; if the matter of fact (whereof the Searchers are Judges) as to the number of those that die suddenly (and 'tis great odds those, for much the greatest part, die of Apoplexies) be clear, as I suppose 'tis acknowledged by all, I see nothing but it may be brought to establish the Hypothesis. Having therefore looked into the general Bills for near Twenty years past, I find the account of those that died of Apoplexies and sudden death (which are there, and, I conceive, may passably enough be reckoned under the same class) to stand thus.  
An. Dom. 
Apop. & sud.  1670 
79.  1671 
63.  1672 
65.  1673 
84.  1674 
101.  1675 
86.  1676 
84.  1677 
66.  1678 
83.  1679 
103.  1680 
95.  1681 
94.  1682 
100  1683 
108.  1684 
152.  1685 
112.  1686 
129.  1687 
110.   
From whence I think the probability, at least, of my Aera may be inferred, whatever may be thought of the notions that are brought to give a reason of it. For the great increase of number in the year 1684 must evidence that; and it seems obviously deducible, that as some great and general cause from the constitution of the season must influence such accidents; so that assigned, from the Coldness, may have that energy here; since both 'twas so remarkable, and nothing else appeared (either upon my own, or any others observation or notion, so far as I have yet learned) fit to stand in competition with it. And from comparing the accounts of the subsequent years with those which went before, there seems reason enough to suppose, that since the indisposition lasted (but in somewhat a lower degree) though the external occasion have ceased, the weakness impressed on the nervosum genus, according to what has been before deduced, is not yet obliterated. And indeed if we take notice of a disease of another denomination in the same papers (which by the dreadfulness of its symptoms is almost as evident as the Apoplexy) viz. the class of Convulsions, we may observe the effect of that impression on the Brain to be so far from vanishing, that it rather seems to be in the increase tho' the symptoms that declare it are altered: that class standing thus.  
An. Dom. 
Convuls.  1670 
1695.  1671 
1650.  1672 
1965.  1673 
1761.  1674 
2256.  1675 
1961.  1676 
2363.  1677 
2357.  1678 
2525.  1679 
2837.  1680 
3055.  1681 
3270.  1682 
3404.  1683 
3235.  1684 
3772.  1685 
3420.  1686 
3731.  1687 
3967.   
So that though the flaceidity, impressed on the Brain from that occasion, may be in good measure by this time abated, and unless the like, or some as forcible causes, happen again may, 'tis to be hoped, quite cease (and I suppose it may be observed that the forementioned frequency of Apoplexies is a late somewhat abated) yet it may however have been so disordered in its tone, as to make secretions of substances out of the alluent Blood (which carries matter for those of very many sorts) which may become so disagreeable to the nervous liquor, as necessarily to produce those terrible symptoms, which tho' they kill not so immediately, yet many times prove as certainly fatal at long running. And the great numbers of vertiginous and other nerval indispositions, which I presume other Physicians as well as myself usually meet with, may very well argue some considerable indisposition impressed on the Brain more of late than formerly which must give a rise to them. And indeed if we observe it we may find (at least I have) that most Fevers of late years, and even at this time, have been attended with nerval Symptoms, as either Tremors or Convulsive motions in the Tendons, or else Comatous affects, Deliria (for the most part slow) or some others of this original: And the Symptoms mentioned by that most curious observer of the changes of diseases, my Learned and Worthy Friend Dr. Sydenham (in his Schedula monitoria de novae Febris ingressu) to discriminate the Fever of this new Constitution from those foregoing, are obviously those of the Brain or Nerves affected as may be easily collected by those that cast their eye on the History of it he lays down.  
So that the notion is not to be restrained to Apoplexies, but aught to be carried farther to many, if not most, other nerval indispositions, which I conceive, may be occasioned by the same general cause. For if it be determined to act on the Brain to its weakening (as I have endeavoured to demonstrate intense Cold is) the constitution of it and its appendices, being very much differing in several persons, it must follow, that diseases of various kinds and denominations may happen, according as the organization of either the Brain, or the Systema Nervosum (which may be possibly concluded to be the whole Body, except the liquors and Parenchymata) happens to be different in some from what it is in others: And indeed the Brain in all persons, who have even the most firm constitution of it, being yet of too tender a one to resist all impressions made by so powerful a cause as the forementioned disposition of the Air was; & being so hard to be restored when once injured; & if that be not fully done, easy to be afresh affected even by much less powerful causes of many other kinds, which frequently happen upon the various mutations of the Air; 'tis no wonder that the Bills should be so filled with Convulsions, aswell as that other nerval indispositions should now adays so much invade.  
But in relation to the numerousness of Convulsions (mentioned, as I said in the weekly Bills) it being objected that their fatality happens, probably, most to Children; which, having been born since that frosty winter, cannot be presumed to have been influenced by it; I answer, first, that the supposition is precarious, since the Bills make no such distinction; so that it may be not altogether improbable that though that mortality may have been most among them, they being the fittest subject of such diseases, yet adult persons may withal have gone to make up the number of the increase: and I see no reason but that since it must be acknowledged some elder persons have before that time died of this disease, they must proportionably contribute to the number now, unless the contrary can be shown, or else some more probable cause assigned, than what I am going to give, why more infants must die of it now than formerly. For, secondly, there seems reason that parents who have received a morbid impression on a part of that consequence, that the Brain is, to the production of seminal matter, and thence the formation of the Foetus, as to the necessary functions of their proper life, may propagate that to the children they beget or bring forth, as well as dispositions to the Gout, Stone, Consumptions, or other confessedly Hereditary diseases; which too, are most of them nerval. And this impression on the Foetus must, in probability, happen principally on that part of it, which being chiefly influential on the rest of the body must have its Stamina laid as soon as any other parts if not before them all: which too from the congruity of substance this has with the analogous' part in the parents, which has the principal effect in the production, may be supposed to be principally affected in the Child. And the Brain having been weakened in the Parents, the reason seems more over much stronger for the production of these than any of the owned Hereditary distempers, if the Parents have ever formerly had Convulsions (which very many have whilst Children, as is generally observable; and I see not but that this is sufficient to make and denominate the same disease, in the Child that springs from such persons, Hereditary) since here is so powerful an operating cause superadded to a seminal debility and impression.  
But 'tis objected by a very ingenious person against the Aera I assume, 1st, That the increase of apoplectics in 1684 being but 44 above the number of those that died of that distemper in 1683 is too small an increase to be taken notice of for establishing it; 2 lie, That there have been two or three great Frosts within the 18 years I mention, without any observable increase of Apoplexies; 3 lie, That (against my suggestion of the great increase of Convulsions) 'tis notorious that any one, that has but the least Spasme before death, in the Bills dies Convulsive, besides those that die of other distempers, particularly the French Pox, whose credit their Friends are willing to save, and so give them in as dying of Convulsions.  
To the first of which objections I reply, 1st, that I think 'tis not the number of the increase in general, but the proportion to that of former years that ought to be considered in this matter. For though the number in itself be but small, yet comparatively to the rarity of the distemper I take it to be so considerable, that few diseases flowing from the Anomaly of seasons on account of the first qualities, except Fevers (which sometimes, I conceive, prove epidemical, even without what we call Malignity) exceed it; being not much under a third part more than that of those that died the foregoing year, and by much more than a third exceeding that of several of the years cited, and more than double the number of those that died in some of those years. So that there is to me a great deal of reason to think the Cold season influenced that increase unless some fitter cause can be assigned. 2dly, That those distempers that lie in the nervosum genus, viz. the solid substance of the Body (or even in the root of it, the Brain, whose texture yet is finer and more tender than that of all the rest of it) or in the Liquors that are contained and carried in it, being seated in a matter less Heterogeneous and more removed from the brisk agitation impressed by the Heart, as they are more difficult to be introduced, so a smaller excess in the number of them amounts to a greater proportion comparatively, than where there are those ready causes of a commotion, as there are in the diseases which are generally called Epidemical (as malign fevers, pleurisies, angina's, &c. from the indisposition of the season.) For these being seated in fluids which are very heterogeneous and lax, and agitated not only with a fermentative but brisk circulatory, and thence very confused, motion, are therefore easily put into disturbances from external morbific causes; the matter of which, if active (as there are particles enough amongst those we converse with that are) may easily insinuate into the Bodies of most persons, especially those who are not of a very vigorous constitution, and may thence excite fevers in them so determined in their symptoms, as this matter is disposed to affect; whereas those that are founded in the nervosum genus require, on the score of the mentioned conditions, a long continued action of the morbid causes, to induce those impressions that must occasion them. From whence,  
(To answer the Second objection) it seems to me no wonder that none of the former Frosts, referred to in the objection, should introduce distempers (though perhaps of the nature, yet not) of the number of those under consideration. For none of those in my memory; nor, so far as I can be informed, in that of any man, were either so violent or long lasting as this, and consequently the degree of debilitation impressed by them, could not be so great either on the Brain or Blood. But perhaps, if a due examen were made (which I have not the opportunity now to do) it might be found that nerval indispositions of other denominations may have succeeded them, answerable to the degree of the impression. However this impression (which, I conceive, from the grounds before laid down, must be somewhat) having not been obliterated (which it may not perhaps in many years) when this great one invaded, might facilitate the effects of it, which without such a procatarxis might have been the less influential on our health.  
But as to the third objection; I conceive 'tis no more than what may be urged against that symptom in the Bills from their beginning. For I do not think that either the searchers, or others who give them the account, were more skilful formerly to distinguish between those distempers we call Convulsions, and Casual Spasmes, than now. And why there should be more of this latter kind now than formerly, I cannot conceive, unless they be the effects of true Convulsions. So that I see nothing but that the assigned compute may hold good; especially since the increase is so very great that nothing but a real fixed cause can introduce it. And as to what is urged of the French Pox, etc. being put in under this Class, the answer is the same, since the same reasons have always been for the concealment; and 'tis known the Pox, and its infamy too, has been considerably longer in the world than Weekly Bills, which are not of an Hundred years standing.  
From these considerations put together, you see my sense of the question proposed; to which I am sure you expected not so tedious an answer. And I assure you I designed not this prolixity: but several deductions still falling in which to me seemed requisite to clear the notion, I am sure you will not expect apologies for my doing that which yourself have occasioned.  
But since you farther require the methods of Prevention and Cure of this distemper, which I have either used or think requisite; Though after what so many Authors, and particularly Dr. Willis, have written on this subject, it seems altogether superfluous to say any thing; yet, to let you see how ready I am to comply with you in this as well as your other desire, I shall venture at least to give you my thoughts in general concerning them; together with my reasons, such as they are, of the administrations to be proposed, to justify my dissent from such, who in any of the particulars think differently from me.  
But first, though not pretending to write an exact treatise of Apoplexies, but only to give an answer to your questions, you are not to expect I should congest Prognostics, according to the custom of Authors when they propose to write solemnly concerning any diseases; yet I conceive 'tis requisite I should lay down, or rather recapitulate, one or two that respect the fatality: more indeed to excuse Physicians (who are generally liable to be taxed if success attend not their endeavours) than for any solid and useful information they can bring; since the cause of it cannot be certainly known but upon dissection. And  
First, if an Apoplexy proceed from any considerable effusion of blood in Specie, 'tis, as I intimated before altogether incurable, since the tenderness of the part is such that it cannot resist the force of the portrusion behind. And since even any stop in the Sanguiferous vessels will, if not presently removed by Phlebotomy or other due remedies, so distend them that either an eruption or stagnation must quickly follow, 'tis not at all to be wondered at that so few escape; since so few are convinced of (what I take to be) the true remedy where there is a possibility of recovery.  
Secondly, that likewise which proceeds from a Polypus must needs prove as fatal, both from the difficultly dissoluble nature of that substance, and the shortness of time medicines (if such there were) that should effect the dissolution, are allowed to exert themselves in: the blood, as I just now said, for want of motion quickly stagnating and growing grumous in any part where 'tis stopped, and so hindering the motion of, and alike affecting, the rest.  
To which yet, thirdly, give me leave to subjoin; that if the Pulse continue any thing strong, the probability of recovery is much the greater, since 'tis an argument the Brain is not wholly overflowed, but that the mass of blood yet continues in its channels, and produces the distemper only by distension: so that when they shall by due administrations be freed from it, there is hope the Brain may return to its pristine condition; at least in some degree. But yet,  
Fourthly, that those who have escaped one fit, are in very great danger of a return; since (as I have before alleged) the Brain, having been once injured, is, by reason of its tender make, so difficultly reducible, in all respects, to its former Tone; and therefore from any, even slight, occasion be afresh more easily disordered. Therefore it very much concerns those who have once escaped that danger, or even that of a great Vertigo, or other Cephalick distempers, to use a good regulation of themselves for the future, and also to persist long in the use of such corroborating means as may at last (Deo annuente) perfectly restore it, as well as keep the blood in a due crasis, and prevent all antecedent causes. Which advice yet very few are apt to follow; two many being apt, when once in some degree recovered, to imagine (and suggest too) that Physicians urge that more for their own advantage than theirs.  
Which premised, I conceive, first, for Prevention, that these two general Indications ought to be proposed. The removing the Antecedent cause, and the corroborating the Brain.  
The former is to be answered, 1st, by general evacuations of humours, whether Laudable, if they be congested in too great a quantity, or Peccant: 2 lie, by keeping up, or, if it be depraved, restoring the blood to its due crasis.  
1 st. As to evacuations; Phlebotomy seems to deserve the first consideration; since, as I have endeavoured to make it out, 'tis either the congestion of the blood in the sanguiferous vessels of the Brain, or its inundation upon it, that is the most general containing cause of it. So that all persons of a Plethoric habit of Body if fearful of this distemper (Fear, by occasioning the contraction of the Brain, the seat of our apprehensions, if not determining the blood to it, at least causing a check of its motion through it, and so a congestion in, or effusion out of, its vessels) as well as those, whose blood, from other symptoms, or the emission of some of it, may be collected to be viscous, especially if they happen, with distension of the Veins and Lassitudes, to be vertiginous, or inclined to pains in the head, aught to take so much away as may, in probability, prevent too great a distension here, and this not only at such times of the year, when the blood is more apt than usual to rise into a Turgescency, as in the Spring and Summer, but at any time when they occasionally find it to be so disposed. And though many may (& are indeed used, too) urge, that not letting blood at all they have hitherto escaped this, as well as other distempers, when some have been ceased, and died too, notwithstanding such their care (which argument too, by the way, may be urged by many of vigorous constitutions against all precaution, against all diseases, and for a liberty for all debaucheries.) Yet since many have fallen into it, who might probably by Phlebotomy have prevented it, as well as that many have by it found present relief when actually ceased 'tis but a secure caution to use the most probable means of prevention; since though all constitutions are not alike, and some may be sensible of weakness for the present (which yet quickly goes off by a little subsequent care) yet experience shows there are very few but find, though they lose very large quantities of blood, they quickly regain it, as (to omit the reasons of it, as less proper for this place) beside abundance of instances that might be brought of those, who, free from the too general apprehensions of the danger of losing it, have had it designedly taken away in large quantities, Spontaneous Haemorrhages, and those from large wounds, might convince person's unbiased by their own, or others, unaccountable fears. Therefore I should propose that any persons who dread this disease, whose blood has not been depauperated by preceding ones, especially if their appetites be generally good, and they use not store of exercise (filling their veins by the one, and not taking care proportionally to empty them by the other) should take away blood at least every Spring; though oftener if occasion require; and much the rather if they accustom themselves too (that frequently fatal custom of) much drinking of Strong liquors; so to keep both the sanguiferous vessels from too large a distension, and the blood more calm. Twenty ounces I take to be about a middle proportion for most to lose; which may, I suppose, bear the proportion of about a twentieth part to that in most Bodies, and not very much less in most, and I believe can do none (under the forementioned circumstances) any hurt, but much good to most, by securing them from the danger of this, as well as many other distempers.  
Besides Phlebolomy, I take moderate Purging to be requisite, in order to carry of viscid and other humours that, from the foresaid impressions made on the Blood as well as the Brain, are apt to be congested; especially in the Bodies of sedentary persons. This may be done usually Spring and fall; provided that it be neither attempted with too violent medicines, nor too long continued, nor too oft repeated (which ill custom yet many Hypochondriacal persons, I have met with, will not be dissuaded from) lest instead of taking a way the luxuriant humours, these medicines, by too much exagitating and disturbing the Blood, introduce the distemper they are given to prevent. But if the stomach be oppressed, 'tis requisite it should be discharged upwards before medicines of the contrary tendency be given; since catharticks, as they can only carry a way thence a small part of that clog that causes the symptom (their irritation not being sufficient in comparison with the emetics, to make it contract itself for a total discharge) so may likewise take a long with them part of that into the Blood; in regard they themselves must be carried into it by the way of the Chyle, to effect the separations of those substances, we find they occasion a discharge of, from it. And indeed the effects of vomiting are very extensive towards the preventing these as well as many other, especially nerval, distempers. For besides the freeing the stomach from any oppressing matter which 'tis very apt to congest, and which, whilst lying there perverts digestion, by either hindering the eruption of, or allaying, or else depraving the liquor designed to exude out of the glaudulous coat of it into the cavity, which I suppose to be the principal digestive ferment: so that digestion being, by the removal of this matter, rightly performed, from the depravation of which most diseases spring, the cause of them is thus cut off; I conceive the irritation, and concussion, made by an emetic upon the nerves not only belonging to the stomach, but (by the consent of the whole nervous systeme) all the Body over, and upon the Brain itself, must occasion them to contract themselves to the discharging of whatsoever fills, or is disagreeable to them.  
Evacuations by Urine may be likewise procured by those who are of a gross habit of Body, or whose Blood is of too close a texture or too viscous; and may be used by such familiarly (premising those forementioned) either by impregnating drinks for common use with diuretics, of which practical Authors have store, or by taking fixed, volatile, or acid salts (all which are diuretical in relation to some or other constitutions) or other more complex ones, as the particular constitution of each person requires, even with our common meats and drinks; they, if fitted to the several dyscrasies (for all are not proper for all indiscriminately; those who abound with acid humours needing alcalizate salts, either fixed or volatile to retund them, or others of an analogous' effect; as others whose Blood, by reason of its too highly exalted sulphureous parts, is apt to be overmuch exagitated, as also those in whom even the volatile salts are too brisk and acrimonious, require acids to mortify them) raising generally no commotion in our Blood, but diverting the course of it from the Brain which 'tis too apt to take. For partly by the congruity their particles have to the secretory passages in the Kidneys, in order to enter into and open them more than those in the other secretory parts; partly by the fusion they make of the Blood, and the reducing many parts of it to such bulks and figures as fit them to enter likewise; partly by their action upon the nerves and their liquor (which I suppose to be the determining ferment in all mixed secretions) on the account of their angles, which fit them to vellicate and incide, as also to accelerate the motion of any liquors they come to be mixed with; partly by absterging, from that inciding power, any obstructing matter, that may lie in the habit of the Brain, as well as any other parts, between the extremities (or term of denomination if they are but continued vessels) of the arteries and veins; they may very well, I conceive, both make the Blood more apt to circulate more universally, and also direct the course of it to the Kidneys, in regard some parts of it being continually, and more copiously than usual, thus taken off from it, the rest must take its course, from other parts where 'twas apt to stop, hither: it being known that it flows most thither, where it finds apertures fit to let it, either in specie, or any of its parts go forth.  
Those evacuations likewise by sweat may perhaps be sometimes attempted with due caution; but neither indiscriminately by all persons, not at all times; and require more than most others the judgement of a Physician to regulate them. For if medecines to procure it be given when the Blood is of a texture not open enough (which both frequently it is, especially near the beginnings of most distempers, and which all persons are not judges of) or when too heterogeneous substances abound in it, they dispose it many times more readily to fix upon the Brain and nerves, than to part with its noxious particles at the designed secretory parts; and a brisker motion being thence impressed on it, the confusion of its parts must be increased; and so if not an Apoplexy, yet other distempers, as certainly, though more slowly, deadly (at least very dangerous and hard to be removed) may be introduced. But this ill custom of forcing meats (whether by inward medicines or outward application) being so common nowadays; as I am satisfied that to this regulation are owing many contumacious distempers which by calming, instead of exagitating the Blood a little disturbed, would quickly have gone of, so 'tis fitting that those should be admonished of the ill consequences of such a method who, (I will believe) out of charity (which yet would be more fitly employed otherways) adventure upon it, especially near the beginning of feverish indispositions, before the morbific matter is digested, and fitted to secede; as well as the multitude of pretenders to Physic, who without a due knowledge of the grounds of Physic (which those that industriously study it, know are not easy to be attained) make this their sacred anchor when they know not what to do.  
Another sort of evacuations for prevention may be proposed, viz. By fontanelles. But though these look speciously, and many are fond of them, and indeed they may be possibly useful to such who have escaped out of one fit, as a constant drain, to divert some humours from the Brain, which, by too much relaxing, or otherwise indisposing it, might occasion returns; this part requiring thence, as I have deduced, a long time, and diligent regulation, to recover its native tone, and so may need all manner of diversions as well as other assistances: Yet to persons, free from other indispositions that require them, I should think them, if not in some degree prejudicial, by drawing away some part of what should be retained, at least superfluous, the humour evacuated at them bearing usually but a small proportion to the daily supplies brought into the blood, which therefore may become much depraved for all the assistance these can give; especially in regard the evacuation is not of a peccant humour in general, but made up of any sorts of particles that can get out of the apertures of the divided vessels, and much different from what is of nature's designation in parts fitly by her Organised upon the first construction. (For I cannot conceive it otherwise elective, than as those apertures, which on the score of the Incision, or Erosion of the Vessels must be large, can only discharge some such, sufficiently for the most part complex, substances from the blood as are of a bulk and figure commensurate to them or less, without any relation to them as disagreeable to the rest of the mass; and so from that largeness of the apertures there must be transmitted a much greater number of useful, than truly excrementitious, substances.) To say nothing of the disturbance which the pain must occasion in a Body otherwise sound. Whereas most of the useful evacuating administrations (except Phlebotomy, which produces its effect mainly by the quantity 'tis used in) make, or presuppose, a laxity, and separation of parts, in the substances from whence the evacuation is to be had, as well as effect it at emissaries fitly framed and disposed to let go such or such determinate humours.  
Secondly; As to the corroborating the Crasis of the blood: Though those who are in perfect health need it not, and medecines of that tendency may perhaps make it ferment too highly, and so perhaps occasionally introduce the distemper which the pretext of giving them is to prevent; yet to valetudinary persons, or those whose blood, upon emission, appears viscous, or is otherwise depraved, I suppose such administrations are very necessary. And to such I would (universals premised) propose a course of bitter medicines, both at Spring and Fall, if they are of cold and Phlegmatic constitutions; as I would advise others, whose blood is too apt on light occasions to be exagitated, the familiar use of appropriate calming medicines. But to all, Chalybeates (to be diversified, and given with different vehicles, according to the several constitutions of persons) may be of most extensive use; and have this to recommend them, that they need no strict regulation, nay their effect is depressed by confinement; stirring and changing the Air both actuating them, and exciting and fermenting the blood, as also strengthening the tone of the parts. Of these, the Chalybeat waters, as those of Tunbridge, Astrap, and (which, I believe, is second to none) Ilmington in your neighbourhood, and the like, drank in Summer (and perhaps at other seasons, but that custom has not authorized it here; though Henricus ab Heers, as great a judge of that as any man, in his Spadacrene, Prescribed them with as good success in the midst of Winter as at any time besides) for a month or longer, are, as the most familiar, and confirmed by the practice of the greatest Physicians of many ages, so perhaps the most efficacious of any preparation of Steel, as being taken up by the water running through the Minera whilst the metal is yet in solutis principiis, as the Chemists speak, and so most subtle and active; if so be the Brain happen not before to have been too much intenerated: in which case perhaps the water itself, Symbolising with the indisposition (especially the quantity considered) may predominate over the power of the Vitriol, dissolved in it, to constringe the before weakened part. And the diversion to be used at the Wells may not a little conduce to the effect of rectifying the blood, by exciting the Spirits.  
But as to the several Chalybeate preparations, give me leave so much to digress (if you will call it a digression) as to say, that I think, if the parts of our body and crasis of the blood are only to be strengthened, and no store of Acids abound; those of them that have been opened by Acids, and so reduced to a Vitriol, are most useful; since they may easily and immediately be distributed, without the trouble given to Nature (which is not always able to actuate a stubborn medicine that needs a strong key to unlock it) farther to prepare them to be fit to enter into the recesses of the body. But if Acids abound in us, the judicious Dr. sydenham's method of giving the braes limature, unaltered (for I believe his Extractum Absynthii can have little of the effect of an Acid upon it) must be the most prevalent of all; since both the intentions, viz. of absorbing Acids, and then strengthening the crasis of the blood, and the tone of the parts, are by it answered; the Acids in the Stomach proving perhaps as fit a menstruum for making a Vitriol, for those uses, as those in the Chemist's hands; whereas the intention of absorbing, if it have place, can hardly be satisfied, if the medicine have been before satiated. And indeed Acids being apt to be so predominant in us, especially in Hypochondriacal distempers, which are so very frequent (as not only very common eructations and vomitings of that kind, but the effect of Urinous Salts, testaceous medecines, the usual antiscorbutics which are generally found to abound with volatile Salts, and other obsorbers of Acids, evince; besides the rationale of such distempers which is speciously deducible from the predominancy of Acids) that great persons proposal of it in that, though gross, yet frequently very effectual, preparation seems to be the most universally solid: though, as I said, if Acids abound not, the others, I should think, would be the most effectual.  
The second general Indication, The Coroborating the Brain, may be answered in a great measure by the last mentioned administrations, viz. the use of Chalybeates; whose effect is generally owned to extend itself to all the consistent parts in the Body, as well as the blood; nay must more to those, than this: since their action upon this is but transient; but those may be presumed to arrest and detain them, though not all, yet as many as their Pores can conveniently receive. For not only their Vitriolate particles, but also the grosser ones, which remain after the abruption of those (as in Crocus Martis Astringens, which is made by the avolation of the Vitriol, upon a long and intense calcination) are confessedly styptical; and therefore being carried in circulation (as well as acting on the Nerves in the Stomach) to the remotest recesses in the Body and amongst them those in the Brain, may be presumed by their lancinations, as forcing them thereby to gentle contractions, to rectify their tone, when too lax, which I have supposed before to be a main condition toward producing the distemper under consideration: And this faculty they must most exert upon those parts whose indigencies are greatest; those whose tone is firm not being fitted to receive, or at least be affected by, them. So that when the Brain has been debilitated, they must exert that action principally there.  
But beside these, a frequent use of the generally owned Cephalicks, as Rosemary, Sage, Betony, Lily of the Valley, etc. may possibly much conduce to corroborate the Brain; and may, without trouble or offence, be used in the Form that Tea is; the general custom having denizoned such a use of drinks: and those whose apprehensions are greater, might besides have those Ingredients fermented with their usual drinks.  
But amongst all the drinks in common use (if you will not suspect the Character given by one, who loves it so well, as you know I do; but who withal have drank it near thirty years, not only innoxiously, but, I seriously affirm, many times to my great advantage, especially when indisposed either at my stomach or head) that of Coffee may perhaps contribute as much to a prevention of the distemper as any; and that on a double account. First by helping the stomach to digest, which it may effect, partly by reason of a gentle Stypticity the particles which make the Tincture have, from the torrefaction of the berries; partly from the actual heat 'tis usually drank with; both which (but more effectually when conjoined) conduce much to corroborate the tone of it; so that digestion being well performed here, and good Blood thence produced, much of the antecedent cause both of Apoplexies and other distempers must be by such administrations prevented: Secondly, by the action it performs, I conceive, on the Brain itself: for, by means of the moderate torrefaction, the aqueous parts of the berry are carried away, and the viscous are altered in their texture; whereby the sulplureous and saline (I dispute not whether preexistent, or made by the preparation, upon the alteration of texture) associating with the terrence, come to constitute little irregular masses, which are not immediately dissoluble (however those particles may be in a tendency to avolation too, by reason of their not very strict combination) but when diluted in the water, after the known manner of preparing the drink, may be presumed to be carried through the mass of Blood in circulation to the Brain; and there, entering into the pores of it, both keep them open for a free passing of the spirits; and withal (especially if daily but moderately, used) keep up the due tone of the Brain by the gentle vellication such particles may make upon it; by which last means it becomes, I conceive principally useful in the present instance. Therefore (for I will not appropriate it to all) it seems to me (agreeably to Dr. Willis's notion, Pharm. rat.) most proper for those who have too lax a constitution of the Brain, as whose intellects or memories generally are slow, and who are much given to sleeping, or to have a dull pain in their heads, especially upon free eating and drinking, or such as are apt to vertigoes from to humid a constitution, or to Catarrhs. But 'tis scarce proper (that you may see how little partial I am) for such as are of an overwatchful temper, of very keen apprehensions, with a thin habit of Body (though I have known some of that habit with whom it has very well agreed: and that observation of agreeableness ought, by prudent persons, to be consulted, not only in relation to this, but most other medecines and even meats, since experience shows that, from undiscoverable, or at least from our shallow insight into things undiscovered, causes, very probable administrations ought to be superseded, as well as the contrary used) and withal for those that are apt to convulsive symptoms upon light occasions (though, I conceive, where, besides the irritative matter that makes convulsions, there happens too great a laxity of the Brain, Coffee, by fortifying the one, may in great measure prevent the admission of the other.) All which to me show the nervosum genus to be of a texture, in such persons, considerably compact, and comparatively dry, with which these particles may too much correspond: and it may be observed that such persons many times contract an unsteadiness or numbness of their hands and other parts, as well as a general indisposedness, and uneasiness by its (even, as to others, moderate) use. And from these effects upon the inconsiderate use of it (as 'tis common to have any, though the best, remedies abused when grown popular) it has amongst many got the imputation of being a Paralytic drink, and disposing to Apoplexies; such never reflecting what multitudes of others, comparatively to the few it injuries, receive advantage by it.  
Perhaps too you will expect my opinion concerning my other favourite, Tobacco. Concerning which I must say that though I know many have an opinion of its being Narcotick, or otherwise injurious to the Brain, and consequently disposing to Apoplexies: yet (to say nothing of my having used it, and not sparingly, for many years, without finding any such effect of it) the very common custom of taking it for so many scores of years since it began to be in vogue, must have made such a quality, if it had it, evidently taken notice of; and consequently common prudence would have obliged people to have left it off long ago, as deleterious, if experience did not evidence the contrary: for there is no man but, if, laying aside prejudices, he will give himself the trouble to observe, may easily find, that very many live to great years, & in as great a state of health as those who take it not, that have long used it, even immoderately. It must indeed be owned that it is not agreeable to all constitutions: but the same may be said of almost any thing else, whether food or Physic. And I presume no wise man will conclude from a few instances of the disagreeableness of any thing to some men, when vast numbers of them on the contrary side may be brought to warrant its use, that it ought universally to be avoided, or branded with a note of infamy. My sense of it is, that in those persons with whom 'tis found to agree, 'tis a very good drainer of humours, and so may supply the place of Fontanels, or at least that fewer of these may be necessary to those who abound with moisture. For, by its irritating and occasionally (from the great afflux of the Saliva) enlarging the secretory ducts in the glaudules about the Mouth, as 'tis evident there must be a great discharge, so a great diversion from the Brain (tho' I own the greatest part of the matter comes not immediately from thence but out of the Blood) in which case 'tis advisable that the persons that take it should drink but moderately; lest otherwise they do themselves more hurt by the supply than they can receive benefit by the discharge of moisture from this or any other evacuations. But there seems another reason why Tobacco may be useful to those who are disposed to Apoplexies (under the supposition of its agreeableness) viz. that by reason of the vellication the smoke of it impresses on the nerves in the Mouth, it makes them contract themselves, and so by consecution the whole Brain comes to be analogously affected. So that if the Brain happen to be more lax than ordinary, and thereby disposed to receive an afflux of Blood or Serum, as I take it to be especially after a person has had and escaped one Fit, as well indeed as in many other cases of preceding nerval indispositions, I see nothing but it may prove a very useful administration, toward restoring the tone of it: and 'tis known to be very advantageous to many Hysterical persons; of which though perhaps other reasons may be assigned, as the altering the texture of the Fermentative particles, by the association of those of the smoke to them as they chance to be admitted, and so those of other figures and bulks may hence emerge; or else the determination of the nerves to other motions▪ by the action of this smoke impressed on the mammillary processes, or other nerves about the Mouth or parts adjacent; yet this seems to me none of the least probable, that by corroborating the tone of the Brain it prevents the admission of those too elastical or otherwise heterogeneous particles into the tubes of the nerves, which are the cause of the symptoms.  
Also the frequent use of Volatile Salts may conduce much to a prevention, under the limitations alleged for the use of Coffee; such as are spirits of Sal Armoniac, Hartshorn, Soot, etc. (which are but such Salts diluted) as being, I conceive so congenerous to those called Animal Spirits, that they must needs excite them in us when too torpid, or supply them when wanting; unless the constitution of the Nerves be too dry or apt to be irritated by them. And their effects have, in many instances of nerval distempers, found been so remarkable, that they are now adays become of very familiar use, though sometimes likewise abused.  
But there are two specious administrations, much cried up, and used by many, which deserve to be taken notice of, viz. Apoplectic Balsams (whose principal use is to be smelled to) composed of perfumes Aromaticks, and other ingredients, reputed Cephalicks, and Snush. Concerning the former of which, give me leave to say, I think them so far from being useful for prevention, that they most ordinarily prove very prejudicial. For by reason of their grateful smell and the great activity of their odorous particles (but without any troublesome irritation) some of them may easily enough be presumed to be admitted into the Brain at the extremities of the olfactory nerves with the Air in inspiration; and being once so, are so far from assisting it to contract itself, that, they much relax and expand it, and consequently dispose it to admit an afflux of blood, especially when before fitted (as I have said) to be congested in, or make its way forth of, its vessels in the Brain. And their influence seems to me to be very great likewise upon the fluid substances in the Brain, which have all some lentor; and therefore these admitted substances, by reason of their activity, may easily exagitate them; whereby the passages must come to be enlarged, and so become capable of an afflux or congestion. I own indeed that, in some cases of Headache, they may be, and have proved a very effectual remedy; as perhaps when the matter that causes it may be acrimonious; but not in the degree or kind to produce convulsive symptoms (all sorts of aculeated particles being not fit to produce one effect:) which the soft particles of these may, by their adhesion, so blunt or sheathe, that their lancination must therefore immediately be taken off. But as these cases are but rare; so also there ought to be a distinction made between the administration of medecines upon an emergency, and their common use when no cause requires it; which last the present caution refers too: for then there is reason to suspect they meeting with no hostile particles, may too much relax and open the pores of the Brain, and so give occasion to the suggested inconveniences.  
If the experiment of convulsive symptoms (which imply contractions) ordinarily excited by these medicines in those who are disposed to Hysterick fits, be urged against this notion, which supposes the distemper under consideration to proceed from a laxity; I answer, first, that it seems probable that these convulsive symptoms proceed from a kind of Explosion, according to the sense of Dr. Willis, which must first infer an Expansion of them, and then a contraction when the due requisites to it concur: for Secondly, the Aromatic particles, though of themselves very soft, and agreeably entering at the pores of the nerves, yet finding, after their admission, heterogeneous and fermentative substances in the Brains of some persons, may be very much inclined from their congress first to agitate, and then in return be agitated by them; from whence the Brain, being vellicated, is forced into contractions to expel them: upon which lucta, too, such corpuscles must, in probability be form, as may prove very vellicating on a second score, and so continue these fits, as being uncapable to be suddenly expelled. Whereas when they happen to be applied to persons not abounding with such fermentative particles, they may only relax the tone of the Brain, and so dispose to Apoplexies on the forementioned account.  
On the same score, I conceive Snush, especially made as 'tis usually, with Aromaticks and Perfumes, and so mild (either on the account of its ingredients, or from frequent use) as not to cause Sternutation, to be prejudicial, instead of being advantageous, to the health of those that immoderately use it, and more perhaps then the Apoplectic Balsams: because both the matter of it is more gross, and thence apt to lie longer about the extremity of the Olfactory nerves, and so continually to affect them; and also the custom of many is, as I have often observed, ever and anon to be supplying more, whereby the pores of those nerves are kept continually open. And I must suspect, that should any Pestilential Season invade (which God avert) such persons, as much accustom themselves to these powders, would, caeteris paribus, be in more danger of receiving infection than others: since from the symptoms delivered by Authors, the pestilence appears to seize the Brain particularly; and the sudden fate recorded of those that, without any preceding indisposition, have, whilst that raged, fallen down dead in the streets, seems not so easily accountable for any other occasion, than that the pestilential Miasmes are admitted at those nerves, since all other ways to the Brain, the source of sense and motion, and indeed of all the actions of life, is the most likely seat of this sudden prostration. 'Tis true, it may be urged, that many which use it receive no apparent injury: and indeed some are of so firm a constitution of the Brain, as well as of the whole Body that comparatively great occasions of sickness will have little or no influence on them, whereas others are affected by very small ones. But I think the objection may as well be urged (as on another score I a little before intimated) by those, who having long indulged themselves in immoderate drinking have yet lived to a great age, when 'tis obvious that many more much shorten their Lives by it. But though not Apoplexies, yet Vertigoes, and other distempers which show the Brain debilitated, may hence perhaps arise.  
Secondly, as to the Cure of an Apoplexy; It consists (according to my notion before alleged of the Cause) chiefly in copious Phlebotomy, since nothing else seems capable of dislodging (at least suddenly: and this distemper of all others requires a Sudden remedy) the morbific matter, For the distension, both of the Sanguiferous vessels, and habit of the parts, being by a good depletion taken off suddenly, the Fibres which constitute both must be presumed to contract themselves by their Tonick motion, but especially those in the habit; the Elastical pressure of the Ambient, as concurring ordinarily. So in this case especially when the resistance within is abated. So that when what is nearest the Heart runs into it with some impetuosity, the rest, both finding room enough in the Veins, and being urged on, not only by the arterial blood behind, rushing into the veins the faster when it has more room, but also by the Systaltick motion now the distension is taken off, must leave its former recesses, and be restored to circulation. Which action is quickly propagated to the Brain, and that put into Analogous contractions. But this may be presumed most effectually to happen whilst the Vessels are only distended before the blood hath made its way forth into the habit of the Brain; which if it once hath, at least in any considerable quantity, the distemper seems scarce at all remediable, either by this or any other administrations; both on the account of the forementioned difficulty, if not impossibility, of its getting out of those recesses into the veins again, and also the yeildingness of the Brain to the Pulsifick protrusion of the blood behind.  
This Phlebotomy, I conceive, aught to be administered to Thirty, Forty, Fifty, or Sixty, or perhaps more, ounces at a time (some persons requiring more to be taken away, some less, according as the congestion and obstruction happens to be greater or less, and the quantity of blood to abound in the Body) if the Pulse (which should be tried during the bleeding) fail not: Otherwise, considering the great quantity we have in our Bodies, 'twill not satisfy the indication. And by such an evacuation, viz. to at least Sixty ounces at once, D. Gibbons of Oxon, (a person whom you, as well as I, know to be, besides his great parts, and general Learning, of that sagacity, and judgement in Physic, that his example must much justify the practice) cured an Apoplexy there some time since, thought deplorable: as, if you question the relation from me, you may be satisfied both from himself, and his Chirurgeon, and also several others that were present. And were it proper for me I could allege Analogous instances of such profuse (if you will call them so) evacuations of that kind in my own observation, attempted with great advantage to my Patients. And if the first bleeding secure not the Patient, it ought after a few hours to be repeated, and so, if need be, several times: there being much more danger from the disease, than loss of blood, which has usually been observed to have been spent (as I a little before noted) upon wounds, or Spontaneous Haemorhages, in much greater quantity without loss of Life; and the consequent weakness has soon been corrected by a due regimen of diet, or perhaps some other assistances. Nay even Old Age ought not to supersede this remedy, however the assertion be like to be censured for very bold by many, who more consult their own fears, than the reason of the thing. For besides that such ancient persons, who are inclined to Apoplexies, generally abound enough with blood, theirs is more apt to grow viscous from their decay, in some degree, of spirits, and their inability to a sufficiently brisk action, requisite to spiritualise, and keep it in a due crasis: so that when apt to distend, or get out of its vessels, it ought to be taken away in good quantities, both in regard the decayed strength of the part affected is not, proportionally to what it formerly was, sufficient to manage it, and return it into its proper vessels, or its usual circulation in them; and also because, if it be in them once grown viscous, 'tis scarce possible it can be corrected for the forementioned reasons; and therefore (according to the sense of the deservedly famous Botallus) ought to be taken away that better, from the supervening nourishment, may be substituted in the room of it: the sanguifying power, though upon a considerable abatement of the quantity, being in the rest sufficient, even in the eldest persons, to transmute the appelling Chyle, which from its previous preparations (we feeding on nothing but vegetable, or animal, substances, which must be highly digested and exalted to be brought to either of those estates; and those farther exalted generally, either by Elixation, assation, or fermentation) wants little of the perfection of Blood, even before its admission into the mass of it; as, if prejudices were laid aside, might be collected from instances, which now and then occur, of old people, who by wounds or haemorhages lose great quantities of it, and yet recover, nay many times increase, the vigour they had before these accidents: and I see no reason why, what nature or chance authorise to be innoxious, may not be attempted by art, when great indications occur, which intimate how unsafe 'tis to permit them to go unsatisfyed. And to countenance this opinion, give me leave to subjoin (though 'twere not hard for me to bring many more instances of this kind) that 'tis near two years since a very worthy Lady, the Lady Yate of Harvington in Worcester-Shire, of the age then of 77 years, was taken Apoplectical, and though the imminent danger of it were taken off before Phlebotomy was administered; yet it left so great a vertigo, and so general a weakness on the Brain, and all the Body (her Ladyship, though before very vigorous, considering her age, and endued with a very great understanding and memory, as all that have the honour to converse with her must testify, being reduced to the condition not to turn herself in her bed, besides a great decay of the intellectual faculties) that to comply with my judgement, and the duty thence resulting to my patients who put their lives under my conduct, I caused (assoon as leave could be obtained) between twenty and thirty ounces of Blood to be taken away, with great, and immediate, success: and the like was done again, in the same quantity, within a week after, upon a fresh increase of the symptoms, without any debilitation from it; but on the contrary with remarkable advantage, both in relation to her recovery of memory and understanding, and also strength of Body. Since which time her Ladyship, using due medecines and regulation, has farther attained so great a degree of these powers, as at these years is much above the expectation of any that were witnesses of her indisposition.  
I conceive indeed (to endeavour to evince a little the utility of Phlebotomy in ancient people; if you will not call it an excursion) Old Age to consist more in the Induration of the Solid parts, than in the absumption, vappidness, depauperation, or any other depression of the spirits in the Fluids; or what we call the Humidum radical: for these fluids are daily repaired, and would be in as high a degree spirituous as ever (considering the previous exaltations just now mentioned) were the solid parts equally disposed to impress due motions on them, and the Strainers, and other passages, fitted as formerly for their transmission and Secretions. Whereas those once growing harder can neither undergo their due contractive motions, as they were wont, nor thence sufficiently effect a division of the particles of these, wherein Spiritualization consists: only the finer and more spirituous (if agreeable) the substances are that are brought to them by the Chyle, the more they must be a new intenerated, and so become more fit to perform their office toward the adapting these for the functions of life. And as to what concerns the celebrated notion of a Humidum radical, which begins with our life, and continues individually the same, tho' in quantity diminished, and allayed (which diminution must on the same account, before it arrives at its utmost periods, cause Old Age;) I can hardly think that, Considering the comparative tenderness of our Bodies, the motions both of our Blood and other fluids within us, and of the Atmosphere, that (in more than one sense) unfathomable menstruum for the dissolution of Bodies, without us, the daily supplies of aliments whose particles are sufficiently on the score of their texture agitable, and the openness of the pores every where; any particles that constituted them at first can continue for any number of years, but must be all, one after another, in no long time thrust forth as these causes come to act on them, to make way for fresh ones, that bring with them a sutableness to the parts, which they, on those accounts, must have lost. For I cannot apprehend any other difference (according to the slenderness of my capacity) between the Spiritus insiti, Influentes, Humidum nativum, if these be corporeal, as I know not 'twas ever doubted, and the Rest of the grosser substance that makes up the Body, than what depends upon the Figure, Magnitude, Contexture, and Relations thence resulting: so that the more fine and subtle any of these substances are, I conceive they are so much the more easily dissipable, and therefore far from being so durable as the supposition of the Humidum radical requires.  
When therefore on any occasion the Blood; in those who have this induration of the parts, becomes unapt to be duly moved as 'twas wont, it seems very requisite that it should be taken away in some such quantity, as to render the motion of the rest more placid (the distension of the vessels being thus taken off) so to make room for what is more fine, and apt enough to be quickly spiritualised, and to become a fitter matter for nutrition (and, if you please, supplies of the Humidum radical) whereby also that degree of rigidness of the parts, by the appulse of this softer Blood, may be corrected, and so, besides the satisfying many times a present and urgent indication, Life prolonged, if this administration were more frequently, but prudently, used, to a considerably longer date, than for the most part it has.  
But to return: If we make but a reflection on the quantity of blood which very able Physicians have concluded to be naturally in our Bodies, viz. from about 16 to 25 pounds according to the bulk and constitutions of persons; which, too, by full feeding, and want of due exercise, may possibly at some times be considerably increased; and withal how that many not only live under great fastings for many days, whether for want of appetite or constraint, which (Evacuations proceeding notwithstanding, at least that of Transpiration, which, according to the observations of the accurate Sanctorius, is much the greatest of them all) must necessarily diminish the quantity of blood much below the proportion that any Physician by bleeding dares (though for reasons not so proper for this place, and the brevity of a letter already swelled too much, the advantages thence resulting in many cases equal not those of a free Phlebotomy) and yet afterwards recover to as good a state of health as ever they enjoyed, we ought to lay aside those panic fears of a comparatively plentiful evacuation this way; especially when the distemper seems hardly superable without it: and a little delay and oversight in this point, as well as in war, puts the matter past retriving. I know large bleedings (nay even in Pleurisies, Peripneumonias, Anginas, etc.) are much dreaded by many, not only of the unconsidering vulgar, but even persons of all degrees, and education, and even by many Physicians of great name: And 'twere easy to cite great Authors, who have either expressed their fears of it, or so mince the matter, that their apprehensions are obvious enough: and he that frequently uses it cannot escape aspersions (expertus loquor) be the advantage to the patient ever so remarkable, and must expect, notwithstanding that, always to be dreaded for a Physician; but must at least be sure to be greatly censured, if, either through the greatness of the distemper, or the (very common unmanagableness of the Patient, either from his own inclination, or others suggestion, success attend it not. But certainly he must have a strict account to give who, taking charge of Lives, will, to their loss or, at least, hazard, be rather swayed by others, or his own, fear than his judgement, but a much stricter, if a prospect of Interest, by complying with people's inclinations (which I am afraid is too common amongst pretenders to Physic) tempt him to deflect from it. And therefore he ought not be concerned at these Bruta Fulmina, but follow the dictates of his reason and conscience. For my own part, though I am far from thinking Phlebotomy proper for the cure of all diseases, or even to be largely administered in most, but that a solid judgement (which I am sure the greatest number of the censurers of it have not) from substantial grounds in Physic, aught to determine when it is to be advised, and when not; yet I think it might be more frequently, and in many cases much more copiously used, than (at least in the place where I live) it is or will be permitted to be: And I should be obliged to him that should convince me of my mistake in this notion (having hitherto thought I had Reason, but I am sure I have had Experience, to confirm me in a good opinion of it) particularly in relation to Apoplexies, as having not been so happy, in my reading, to meet with that satisfaction; Or shall propose such other certain remedies, or methods of cure, as would supersede its use in this, or other cases, that I think require it. But I must subjoin, that I cannot but much wonder that Barbette a Physician of Considerable reputation, and whose Praxis is in the hands of all Physicians, should have those ill notions of Phlebotomy, as to reflect upon it, as the cause of the miscarriage of the Apoplectical patients, he instances in; when both 'tis probable, from what he says, there was but very little blood taken away, and also 'tis easy to be collected he never durst try the remedy in its due latitude; but, in compliance to his prejudices, would rather let them die under a (without this) unpromising method, than attempt a cure by it, against which (whatever he could) he does not urge any reason of moment.  
As to the place where Phlebotomy ought to be administered: though there being a Circulation of the blood, any part of the Body, where a Vein can be readily come at, may be proper enough; since the Vessels being considerably emptied any where, the remaining blood will, 'tis known, come from all others, especially that where 'tis too much congested, to fill them again, and so keep up the proportion every where (and the forementioned Systaltick motion must whem the Plethora is taken off, assist the brisker circulation through parts before distended:) Yet the jugular, if it can be met with, is the most proper Vein for this discharge, since it evacuates immediately only from the head; whereas those of the Limbs, do it but mediately, as requiring a good quantity to be taken away, before what lies in the Brain can come to be extruded, according to the known laws of Circulation. And this may recommend itself the more to the timorous Assistants; since so 'tis likely the relief will be as the more speedy, so with less expense of blood.  
But besides (but especially after) Phlebotomy, I conceive other remedies ought to be, with all speed, used, as Vesicatories, Cupping glasses, Sternutations or other Errhines, Apophlegmatismes, acrimonious Cataplasms to the feet and wrists, Volatile salts or Assa foetida, or the like, in odour, and any other Administrations in order to excite, and make the Brain contract itself, to expel the morbid matter, as well as to divert the course of it: as also that inwardly be given spirit of Sal-armoniack or other Volatile salts, Castor, and other brisk Nerval remedies, which may so irritate, as to cause a corroboration of its tone; that so the effused, or congested, matter may come to be extruded, and at last resumed by the veins. To this intent likewise, Vomitories, and Purgatives (of which, as of the rest, Authors have store, as for the due administration of them the presence and judgement of a Physician is necessary) ought, as occasion is, to be brought into use. And if the distemper begin once to yield to the efficacy of these remedies; As I before intimated, so I must again suggest, that corroborating ones should for a long time be insisted on, to restore the Brain and the Nerves to their pristine tone.  
After all give me leave to subjoin that you may collect a great Specimen of my deference to you from hence, that for the satisfaction (which yet I am afraid they'll think not given) of some of your Friends, as you suggest, to whom the Latin tongue is not so easy, I publish this (against the advice of some great ones of my own, and those great Judges) in our own Language, when most of the speculations had been (perhaps) as easily, but more fitly delivered in that; and withal, give me leave to say, several of them so much out of the way of those, that understand only the English tongue, that few such will, perhaps relish them. And indeed though nothing here brought, can be pretended at all instructive, either to yourself, or other great Physicians of this Age (than which none ever enjoyed numbers of them of greater, if equal, abilities) but must be looked on as very jejune, as being drawn up by one who is so very conscious of his own inabilities, that it may be construed arrogance to appear at all thus publicly; yet since I must so far descent from you as to believe, 'tis likely the Discourse may meet with not many Readers but those of the Faculty of Physic; who perhaps out of curiosity may give themselves that trouble; though but to censure the composer; it ought at least to have been written in the Language in which you are most accustomed to employ yourselves. But I must needs say the argument you urge, from the example of the very great Mr. boil, Dr. Henshaw, and several other great, as well Physicians, as Philosophers (not to urge that of former Ages) both of our own, and neighbouring Nations, who have thought fit to write in their own Language) particularly the very learned Dr. Tho. Burnet, who has been pleased to oblige his own Nation, by publishing his most curious Theory, and that much improved, in its own, after he had done it first in Latin) has enough in it to plead my excuse to those who advise the contrary.  
But indeed there may be one reason of moment, I conceive, alleged, why 'tis fitting something should be written in the language of each country concerning this, more than any other Disease; viz. because this, of all, requires the speediest relief: and Physicians not being always at hand, Charity obliges that all should have such remedies made known to them as may put a stop to the danger, till farther help can be had. And Phlebotomy being that great, and almost certain, (not to say only) one, when there is any hope of recovery; as 'tis fitting the generality of people should be convinced of it, as well as their danger without it (though indeed it may be suspected, so great are the prejudices most have, not very many will) and therefore, if any be seized, others should have immediate recourse to it for them, without staying for a Physician; so it may be some farther Apology for my adventuring to gratify you, since no Body else, that I know of, has in English written ex professo of it singly; at least with those convictions, which I have upon me, of the necessity of this Remedy.  
However I must herein own your friendship; that since you will have me write, you would have me do it with that advantage to my reputation, not to expose my weakness, by attempting it in the Learned Language; wherein you must be conscious, from former instances, how much I am deficient. If any of my notions, here delivered, suit not with yours, I expect, in return, your sense upon them; which, If convincing to my understanding, shall be gratefully acknowledged, and subscribed to, by,  
Sir, Your most Faithful Friend, and Servant WILLIAM COLE. Worcester, Aug. 20. 1688.   

ERRATA.  
PAg. 43. line 17. for Excrasie, ●●ad Exercise, p. 76. l. ●●. we may. p. 129. l. 10. r. may from. p. 142. l. 3. r. Sweats. p. 151. ult. r. absumption. p. 170. l. 4. after Brain, r. seems farther about: and I suppose 'twill be allowed that the Brain.  
FINIS.