ought to be in Motion p. 164 The Use of the Lungs in respect of the Body p. 169 To dilate the Ventricles of the Heart p. 174 How obstructing Respiration kills an Animal p. 178 Whether Air be mixed with the Mass of Blood p. 191 Whether Nitre be p. 192 And how p. 193 What Effects it hath upon the Mass of Humors in the Lungs p. 196 How Nitre depresses the Heat of the Blood p. 198 Pag. L. Read 41. 5. Occasion for Accension 53. 18. Motion for Notion 60. 2. Exploded 84. 8. Blood for Body OF THE HEAT OF THE BLOOD EVEN Philosophy in General is so Mysterious and so infinitely out of the reach of our short and weak Capacities that the best of Philosophers may truly be said to have but a slight and superficial Knowledg of it For if that small Part we know be compared with what we know not all our Knowledg is but as an invisible Speck those things to which it extends being inconsiderable if compared with that vast and endless Mass of the Universe But although that Part of the Universe which in some Measure lyes within the Cope of our Senses be small and inconsiderable when compared with the vast Extent of the whole Creation yet when we reflect on the vast Variety of Objects contained within those narrow Dimensions we find and must needs acknowledg it very considerable and superabundantly furnish'd with Matter for our Senses to work upon For the Extension of our Knowledg as to those Objects is bounded by Limits not very spatious notwithstanding the Diligence and Industry of Learned Men and the great Improvements made in most Parts of Knowledg The wisest Men and the most profound Philosophers must of necessity own that of those Things they know most their Knowledg is very imperfect We know but in Part and indeed so small a Part that it chiefly seems to inform us more sensibly of our Ignorance But so pleasant and desirable is Knowledg and we find so much uneasiness in Ignorance when once we have tasted of it that it 's impossible to abstain from a further Pursuit after it at least notwithstanding the vast disproportion betwixt our Knowledg and Ignorance which continually lyes in our way to discourage us And as we thirst after Knowledg with a desire to attain to a more adequate and compleat Apprehension of it so we most eagerly pursue those Parts of it which we hope to understand most clearly and which we expect to make a Progress in with the most considerable Advantage Since then the Microcosm which is as if it were a Type and Epitomy of the Macrocosm lyes much more within the narrow Cope of our Senses since we can dive and search into all and the inmost Recesses of it and come nearer to those Springs and Fountains upon which all the Effects we perceive in it depend we have much more solid and firm Foundations to proceed upon than in any other Parts of Philosophy whatsoever and may much more reasonably hope for Certainty and Truth besides the Pursuit of it must needs be not only more Pleasant but Advantagious And although in a Man's Body some Things are much more apparent clear than others yet the most obscure may easily be so far explained and understood as is necessary and subservient to shew the Use of them and to what Ends they were designed Amongst those that are accounted most obscure the Heat of the Blood is unfortunately one but the Reason why it is so is not that it is less apparent in it self but rather the Inadvertency of those that searched into it If possible such great Men as have writ concerning it may be guilty of so great a Fault which although otherwise no small one is much more excusable in those whose more weighty Concerns take 'em of a deeper Enquiry Since then so many learned Men and those to whom Physick is not least obliged for considerable Improvements have writ on this Subject I think it not only Justice but also Reasonable I should shew upon what Grounds and for what Reasons I have rejected their Opinions before I take leave to propose my own It would be needless to spend time in Informing my Reader that both Antient and Modern Writers have endeavoured to account for it and it would be Information to but a few since none that have made any considerable Progress in Physick can be ignorant of it I shall only as briefly as I can mention the Opinions of the Antients that it may better appear to the more unlearned wherein they are deficient and then I shall consider the most remarkable Opinions of the Moderns that less competent Judges and young Students in Physick may spend less time in convincing themselves how far they come short of explaining the Reason of the Heat of the Blood Amongst the Ancients who wanted those Improvements in Anatomy that have been made of late to direct them in their Judgments some fancied that it proceeded from a Calidum innatum or innate Heat which was fixed and rooted in all the Parts of a Man's Body before his Birth and that This continued Heat by communicating it self successively to the Nourishment of the Parts as soon as it was received by them Which indeed was so weak and superficial an Account of it that it rather served to please the Unlearned then to satisfie the Curious and more Inquisitive Others thought that there was a sort of Flame lodged in the Heart which kindled the Blood as it passed through it But Moderns having learnt by a further and a deeper Insight into Mens Bodies that the former of those was rather the Effect than the Cause and by frequent Dissections that the Heart was altogether incapable of containing such a Flame and also that that which they supposed to be the Pabulum of it to be clotted Blood they have with sufficient Reason rejected them both Wherefore passing by these I shall proceed to consider those Modern Opinions which are thought most worthy our Consideration The first that I shall take Notice of is the Opinion of the most Ingenious Dr. Willis who although in some things he hath had the Fortune to be mistaken with other Learned Men the best being not exempt yet for the most part hath made the greatest Improvements of any of his Predecessors in Theory This Learned Author in the eight Paragraph or thereabouts of his Exercitation concerning the Heat of the Blood takes Notice that there are three Modes or Sorts of Causes by which Liquids grow Hot. First à culido ad moto or by applying them to something that is Hot as when Water boyls over the Fire Secondly when Saline Corrosives mutually act upon one another or on sulphureous Bodies mixed with them by an intense and powerful Agitation Thirdly when a Liquor abounding with much Spirit or Sulphur takes Flame from some other Body And in the next Paragraph
he says that there are other ways of Calefaction as Fermentation Putrefaction and Attrition but the seare only observable in solid Bodies The Design of which is to prove that since the Blood hath not any other Body applied to communicate Heat to it and since it is not impregnated with Saline Corrosives but is sufficiently stocked with Sulphureous Particles and since Fermentation Putrefaction and Attrition are only the Causes of Heat in solid Bodies It must needs be preserved in a continual Heat by Accension of it's Sulphureous Pabulum But if we do but duly consider how Heat is promoted in all these several sorts of Substances it will presently appear that in Philosophy there is but one way by which all whether Liquid or Solid grow Hot and if so then it will follow that whether we say the Blood grows Hot by applying of a hot Thing to it or Saline Corrosives whether by Fermentation Accension or Attrition it will be equivalently the same To make it evident then that there is but one way by which all Bodies grow Hot and that to say that the Heat of it proceeds from the Application of other hot Bodies Saline Corrosives Accension Fermentation or Attrition is but to express the same thing several ways since they are all equivalently performed the same way we are to consider what is the Nature of hot Bodies and wherein their Power consists either to cause Heat themselves or to communicate that Power to others And because several remiss Degrees of Heat differ only in Proportion from Fire which is the most intense and because That is free from those Masks and Clouds which intervene it and our Senses when it is in more remiss Degrees the best way to understand the Reasons of Heat will be to consider wherein the essential Nature of Fire consists Amongst Philosophers although it is very dubious what it is that causes Fire to differ so much from all other Substances yet it is by the Consent of most Moderns and evident from Flame it self and the manner that it destroys other Bodies by that it is made up of rarified Matter whose Particles are in a swift and powerful intestine Agitation and of a peculiar Figure and Size And if Fire be nothing else but Matter rarified and in a swift Motion and from that swift and intense Motion of Matter affecting our Organs of Sence we perceive Heat we must needs conclude that whatever rarifies Matter and puts it's Parts into a brisk Motion is the cause of Heat And although according to the Diversity of Subjects that Heat is dispersed through it hath different Appearances to our Senses and in most it 's Light which when it exists seperately is always joyned with it 't is obscured by the Interposition and Mixture of other Matter yet if Heat depends Essentially upon the Effects that rarified Matter in Motion hath upon our Senses it is undeniably true that Heat is caused only one way Remotely and Proximately with respect to Matter in Motion and the Effect it then hath upon us viz. By puting the Parts of Matter into a brisk Motion to affect our Senses with Violence enough to cause such a Sensation But before I proceed to a further Proof of what I have asserted viz. That there is but one Way in Philosophy by which all Things grow hot it being a Controversy whether Heat be actually in the Body that causes it or whether Matter in Motion only produceth such an Effect as the Sense of Heat upon our Sensory although it is not requisite I should here Publish my Opinion of it yet it is necessary I should explain what I mean when I say that Heat is only produced one Way or that Heat is caused by putting the Parts of Matter into a swift Motion or that Heat depends on the Effects which rarified Matter hath upon our Senses when it is in Motion But if I were here to declare my Opinion of this Point which is so differently held by various Philosophers I should say that as far as I can conceive of it Heat is not actually in the Body that causes it to be perceived by our Senses but potentially in as much as that Body hath a Power to cause such a Sensation And although a great many may wonder that Fire which causes Heat should not be hot it self yet there is as much Reason to believe that it is not as that a Sword which will cause Pain is not Pain it self For those who think that Fire which causes Heat is Heat it self take the Cause for the Effect and affirm it to be so Besides Heat being only a Sensation and it being impossible there should be a Sensation where there is no Sense it is impossible there should be Heat where there is only Fire and no Sense for it to work upon For Heat is not a Mode of Matter rarified and in Motion but an Effect of Matter so modified But say they it is impossible for us to think so truly if we are not directed in our Thoughts by Reason we may irrationally think that Matter in Motion which only causes Heat is Heat but if our Reason proceeds upon those Mediums which our Senses furnish us with and certainly we can on no other we shall easily be induced to believe that the Cause is not the Effect there being a great deal of Reason for us to believe so though none to the contrary When then I say that Heat is only produced one Way I mean that there is but one Way to modify Bodies so as to make them capable of causing Heat when they affect our Sensory And when I say that Heat is caused by putting the Parts of Matter into Motion I mean that a Power of producing Heat is caused so And when I say that Heat depends on the Effect that rarified Matter hath upon our Senses I mean it is caused by those affecting our Senses And because always when I have occasion to mention the Cause of Heat it would be too much Circumlocution to say the Power of causing Heat is produced so or otherwise I shall use the Word Heat sometimes to signify that Motion of rarified Matter which is sufficient to cause Heat and shall call that Motion Heat in respect of the Effects which it causes But to proceed to a further and more evident Proof That Heat or a Power to produce it is only caused one Way we are to consider how the Motion of Particles is carryed on in all those which Dr. Willis calls different Ways of causing Heat viz. per admotum Calidi Saline Corrosives Accension and even Fermentation and Putrefaction And first when Water is put over the Fire and heated per admotum Calidi the fine Particles of Fire penetrating the Vessel are imbibed into the Water and being fettered up and kept from flying away by the Parts of the Liquor put them also into a quick Motion from whence proceeds a sensible Heat In
Animal Spirits are too high and volatile or too much in Quantity they raise this Fermentation so high that the Blood is presently put into a Preter-natural Heat from whence proceeds that Preter-natural Heat in Fevers And the way that Physitians either do or can take in such Cases is either to take down the Animal Spirits by withdrawing Part of their Pabulum and by Acids given internally to harden the Texture of the Blood and make it less subject to grow too Hot by Fermentation or otherwise by cooling and fixing those predominant Spirits and evacuating other accessory Causes by proper Excretories and Emuctories of the Body Lastly That the more any rarified Sulphureous Body is expanded betwixt the more gross and solid Parts of Matter those gross ones are put into a stronger Motion is evident from a Musket charged with Shot which with a small quantity of expanded Matter will scarce be moved but by a greater quantity of exploded Matter are put into so swift a Motion that they fly forcibly a considerable way Having thus far proved what I proposed to be reasonable and likely and nothing but what is consonant to the Practice of most Rational Physitians I proceed to shew that the sharper the Particles of the Blood are they corrode and grind the Spirits into small and minute Particles with a great deal more Violence and by that means cause them to expand more vigorously and by putting them into a strong Motion cause a higher Degree of Heat This is sufficiently proved by the Preter-natural Effects that Scorbutick Salts cause in some People for when the Mass of Blood is impregnated with Acid Acrid Humors these meeting with the Spirits cause Preter natural flushing Heats which appear in several Parts of the Body and sometimes in the whole which are so violent that those that are affected with them complain that they feel themselves as Hot as if they were in a Stew or a Bagnio That this Preter-natural Heat proceeds from Corrosive Salt Humours fermenting with the Spirits is very manifest since these Symptoms are only curred by such Medicines as correct the Acidity and Acrimony of the Blood viz. When it most partakes of Acrimony by sweet diaphoretick Decoctions or some sort of Acids which dull and take off their corroding Edges or when they are more Acid by volatile Salts that carry them off by Sweat or Urine or by Acid Absorbers which by correcting the Acidities of the Pancreatick Juice leave the Ferment of the Liver more predominant and the bitter Choler being by that means bred a great deal more plentifully digests and carries off those crude Humors which by the aforesaid means being made thin enough to go off by Urin and insensible Transpiration are dispersed and carry'd off those ways and the Mass of Blood being cleansed of those sharp Humors is reduced to a healthful State If then by considering the Nature of those Medicines that correct vitious Humors we may learn to know what is the Nature of those Humors we must conclude that whatever is corrected by Medicines directly contrary to Acrimony the nature of that Humor is Acrid and when by the Use of volatile Salts the distempered Humors of our Bodies are attenuated and disposed to Evacuation and at the same time we know that volatile Salts by volatizing and preparing the superfluous fixed Acid Acrid Humors of the Mass of Blood dispose them to be carried off we have all the Reason imaginable to conclude that when we find those Medicines carry off such Symptoms that they are caused by such Humors And that these flushing Heats in the Scurvey proceed from Acrid Acid Humors is plain because all Salt Meat that abounds with Acids and all sharp Acrid Bear that hath an Acrid Fluid Salt predominant in it as also Vinegar and such like make those Symptoms more violent If then both from the Method of Cure and the Cause it self augmented by such Sorts of Juices we gather they proceed from sharp Acrid Acid Humors we may be certain that those Symptoms are caused by such Humors grinding and corroding the Animal Spirits and that by putting them into a Preter-natural Motion they are the Causes of such Sensations And that those Sensations only proceed from thence we may easily conceive for since as long as those Humors circulate with the Mass of Blood and forcibly meet with the Animal Spirits they can only affect them by moving amongst them they must needs put them into a more swift Motion and an unusual Expansion by corroding and grinding them more powerfully betwixt their Particles which is evident from the cause of those flushing Heats I just now mentioned and from the Reason I have before given of Heat But that the sharper the Mass of Blood is the more the Animal Spirits are ground and expanded betwixt the Particles of it is evident from Reason it self for it being proved before that the Heat of the Blood proceeds from a swift intestin Motion of the Particles of the Blood and Spirits caused by Attrition nothing is more Reasonable than that the more solid the Mass of Blood is the stronger the Attrition is and consequently the Motion of Particles which upon our sensory cause heat must be more violent and as in striking of a Flint with a peice of Steel the more firm and hard the Steel is the more powerfully it loosneth the Texture of the Flint and strongly expanding it's Sulphureous Particles puts them into that Motion which constitutes Flame so by Parity of Reason we may expect that the Particles of Blood will cause the Sulphureous volatile Parts of the Spirits to expand more powerfully the more solid and compact they are And that the Texture and Constitution of Saline Humors is more Solid and their Parts more Corroding than of a sweet Balsamick Liquor I think none can deny who compares Vinegar and Spirit of Vitriol with Tincture of Sulphur and although in Fevers where the Blood abounds with too much exalted Sulphur Spirit of Vitriol and other Acids cool the Blood by fixing the Spirits and Coagulating the Sulphur yet when the Blood is impregnated with Scorbutick Salts Acidity joyning with Acrimony causes Heat by corroding the Spirits when they want a Mixture of crude Sulphur to dull their Edges of which it would be no difficulty to convince those that are considerably troubled with scorbutic Symptoms But furthermore I shall prove that the Mass of Blood the more it abounds with volatile Salts and Sulphurs is more easily put into a violent Heat and that it's Particles being more easily put into Motion readily joyn with the Animal Spirits and encrease theirs and that on the contrary the more dull and phlegmatic any Body is the less apt are it's Particles to be put in Motion And as it is commonly taken notice of in all Bodies so it is not less observable in the Mass of Blood for we always find that the least quantity of any volatile Liquor
Title does not at all diversify the Action But if any one would rather signify the Heat of the Blood by any of these different Words I shall be equally pleas'd with them or any of them provided they all meet in the Matter signified by them and do not deny that which seems to be true That the Heat proceeds from a swift intestin Motion of it's Particles Which Motion is the Reason why it affects our Sensory so as to cause a Sensation of Heat But as the Reason why it affects our Sensory so is not sufficiently satisfactory to explain what is the Cause and how it comes by that Power of causing such a Sensation In making an Enquiry into the Cause of that I shall beg leave to make Use of that Word which I think to be most expressive viz. Fermentation For since in every mechanical Action there is an Agent and a Patient and the Agent operates upon the Patient by moving powerfully against the Parts of it And in that Motion the Parts of the one strike against and rub upon the other so far it may be called Attrition And if by the force of the Agent the Motion and consequently Attrition be more violent and the consequence of that Attrition be a Production of a Power to cause a Sensation of Heat so far it may be called Fermentation If then in causing the Heat of the Blood there be such a Motion and Attrition and the consequence of it be Heat we may properly say the Blood grows hot by Attrition and Fermentation But because to signify the Heat of the Blood by Attrition and Fermentation would be needless I would signify all that Action by Fermentation And when I say the Blood grows hot by Fermentation I would be understood to mean and signify both that Attrition of Parts which is the Cause of Fermentation and also Fermentation which is the consequence of Attrition yet if any one would rather say it grows hot by Accension they have my assent provided they mean thereby not so high a degree of Heat as is usually signified by that Word but since it sounds rather too harsh and implies too high a degree of Attrition and Fermentation than that which is commonly in the Blood I more willingly make choice of the former viz. Fermentation And since I have said thus much of the Use of Words applyed to signify the Heat of the Blood I shall here take Notice of what was by way of Discourse told me by one to whom I communicated in some Measure my Notion concerning the Heat of the Blood which was this He said he thought he could prove that it was done by Mixture and Pressure and that he could explain the Heat of the Blood by that Notion I shall here conceal the Authors Name because he hath not made it public upon this account though upon some others to very little purpose and because he told me he intended to publish it I shall for his satisfaction and also the satisfaction of those to whom he hath communicated it say that as I have shewn that in mechanical Actions there is a Motion and by that Motion there must be implyed a Mixture to any one that doth but understand the Circulation of the Humors in a Man's Body and it will consequently follow that where there is a Mixture and a Motion of Humors there must needs be also an Attrition of Parts so moved which Attrition implies a Pressure For there can be no Attrition without a Pressure tho' Pressure does not imply Attrition This is all he told me and consequently all that I can Answer but for as much as I cou'd gather from the remaining Part of his Discourse the most Essential Part of his Notion but from what he said it appearing not what Pressure he meant that is a Pressure of what whether of the Particles of Blood with one another or not and it being plain that he did not believe that Animal Spirits circulated through the Nerves I not only concluded that his Pressure was only of the Particles of Blood because there are none other except Serum to mix with it but also that what he had to say for it was rather about the Use of Words then any thing else and therefore I have shew'd him how far his Words are significant in my Hypothesis But Words whereby we signifie the Heat of the Blood being nothing at all to the Cause of it and to dispute whether it may be called Accension or Fermentation not at all informing what are the Principal or Accessory Causes of it I shall proceed to shew how it is begun and carryed on and by what That is what Humors are Active and what Passive in producing Heat or a Power to Heat and how they are so and after what manner as also where they chiefly operate And that it may appear we are to consider that the material and corruptible Part of a Man in which the immaterial and immortal is lodged is made up of Solid and Liquid Parts the Solid Parts are all those Vessels that make the Body a curious contrived Vascular Engin which are filled with and actuated by Liquids and in which they all circulate And as those Vessels carry different sorts of Liquids so they are called by different Names Veins Arteries Nerves c. Through the Arteries and Veins the Mass of Blood continually circulates and Animal Spirits through the Nerves The Veins and Arteries being as if it were both rooted and springing from the Heart are branched up and down the Body both through the External as well as Internal Parts except those that the Vena Porta supplyes and the Nerves taking their Original from the Brain and spinal Marrow are dispersed through the whole and meeting with the capillary Terminations of the Veins and Arteries they being interwoven one with another terminate all together and as I Metaphorically expressed it in my Treatise of Muscular Motion all terminate in small Glands in the Cavities of which both through the substance of the Muscles as well as the Internal Parts the Arteries lay down Blood and the Nerves either mediately or immediately Animal Spirits and having there also proved that a subtile Liquor made and prepared in these Glands by Formentation was according to the different degrees of Spirits sent there by our Appetite not only subtilized but thrust out by a succession of Matter into the Fibers and circulating through them distends 'em and by that means contracts the Muscles and there also having shewn that the Fermentation was caused by a mutual Conflict of the Blood and Spirits I shall now in this Treatise endeavour to explain from that mutual Conflict the Heat of the Blood And because some as yet doubt whether Animal Spirits circulate through the Nerves or not and others though they are willing and find it necessary to grant that Spirits do really run through them yet profess that they cannot be demonstrated
A TREATISE Concerning the HEAT OF THE BLOOD And also of the USE OF THE LUNGS By RICHARD BOULTON of Brazen-Nose College in OXFORD LONDON Printed for A. and J. Churchill at the Black Swan in Pater-Noster-Row 1698. IMPRIMATUR JO. MEARE Vice-Can Oxon. Jan. 24. 1697. HUNC Librum cui Titulus A Treatise of the Heat of the Blood c. dignum Censemus quî Imprimatur Thomas Millington PRAESES Samuel Collins Edward Hulse Richard Morton Charles Goodall CENSORS Martij 5. 1697 8. TO THE Reverend Dr. JO. MEARE PRINCIPAL OF Brazen-Nose College AND VICE-CHANCELLOR OF THE University of Oxford SIR IT is not any great Opinion I have of my present Performance though there are some who would perswade me that it is not altogether despicable that makes me presume to prefix your Name before it Indeed amongst Men of Sense and Learning Truth for the most Part brings it's own Recommendation along with it and finds that Candid and ready Reception which it deserves But the Generality of Mankind will not relish any thing that bears not in the Front some great and eminent Name And for this Reason it is that I have made bold to make this Dedication Your real Worth which hath deservedly placed you in two Eminent Stations to both which you do more Honour than you receive from them And the Encouragement and Favour you shew to all Persons of Industry Vertue and good Learning under your Government soon determined me in the Choice of such a Patron though my small Share of each of the latter could merit neither of the former And here according to the usual Mode of Dedications I might easily enlarge upon so fair a Character But as it is your peculiar Delight to oblige do good with all the ease and sweetness imaginable so with as little Noise and Ostentation possible And I should sooner hope for your Pardon for this Presumption and the Faults of my Book than for such an Attempt upon your Modesty I shall therefore only add that you would be pleased to accept this as a Testimony of my Duty and Gratitude and that I shall always remain Reverend SIR Your Ever Obedient and Obliged Servant R. BOULTON To the very LEARNED AND JUDICIOUS Dr. R. ANGELL Resident in the CITY of CHESTER Learned Sir SIXTEEN Years Education in a University and a great many more improved in succesful and judicious Practice hath sufficiently qualified You for a Judge and Patron when I consider the former and withal my own Weakness I confess I have less Reason to desire the latter But sinoe it usually happens that those that are least subject to Faults are commonly candid Criticks and most ready to forgive others I am bolder to beg your Patronage yet not for it's Faults since that is below your Judgment but whatever Truth is contained in it which will scarce be deny'd by One that is so much an Encourager of Learning But perhaps I ought to make an Apology to You as well as the World for deviating from the Opinions of some Learned Men especiatly of that never too much Honoured Dr. Willis who was One of the Greatest Physitians of his and preceding Ages And truly all that I can say for my self is That as it would be below the Character of so Great a Man to write any Thing upon any other Consideration than an Improvement of Knowledg and Truth so undoubtedly he would not desire any Thing he writ should be believed except it seemed so That then which I hope will be an Apology for such an Attempt is That I have considered his Opinion with no other Design than an Endeavour after Truth and have offered nothing against his Opinion but plain and unprejudiced Reasons and though I have given Reason enough to prove he was mistaken in this Point yet I must ever have the greatest Veneration and Esteem for all such Men of unparallelled Worth and Learning and so candidly Ingenuous But whether this little BOOK may pretend to any Reason for what it offers or not I am more encouraged to ask Your Patronage it being approved by Men of noted Learning and eminently Judicious the President and Censors of the College of Physitians of which Number that your Self is not a Member no other Reason can be given but that Your own Choice of a more retired Life hath fixed you in that CITY where you are now resident to the Satisfaction and Good of those that commit themselves to your Care But Learned Sir That I may not press too much upon your Patience That Patronage which you were pleased to Give my Last when I was a Stranger to You both encourages me to hope for it now You have been pleased to take me into Your Favour and also that You 'll Pardon me for taking this Liberty since it is only designed to testify my Gratitude for those Favours You have already been pleased to Confer on Your very Humble and Obliged Servant R. BOULTON THE CONTENTS THE Introduction Page 1 Our Knowledg is very short ibid. And Imperfect p. 3 The Pursuit of Knowledg very desirable p. 4 Where most easily attained p. 5 The Heat of the Blood not obscure in respect of it's Cause p. 6 The Opinion of the Antients very Superficial p. 9 Dr. Willis's Opinion answered p. 11 But one Way by which Bodies grow hot p. 13 Fire is rarified Matter in Motion p. 16 Heat not actually in the Body that causes it p. 19 Heat only a Sensation p. 20 Heat only produced one Way proved further in Answer to Dr. Willis p. 23 An Objection answered p. 27 His comparison of the Blood 's Accension with Flame answered p. 28 Several Degrees of Heat without Flame p. 29 Nitre makes no Part of the Flame p. 32 How Nitre promotes Flame p. 33 Why a Candle in a Glass-Globe is extinguished by extracting Air. p. 36 Whether Nitre promotes the Heat of the Blood p. 39 Liquids fetter up Heat without Nitre p. 41 Blood may grow hot without a Sulphureous Pabulum p. 42 His Comparison of the Recrements of Flame and Blood answered p. 43 A Digression why Flame usually ascends p. 50 Why it sometimes descends p. 60 Diemerbroek's Opinion answered p. 62 Dr. Henshaw's Opinion answered p. 65 Of the true Reason of the Heat of the Blood p. 67 Animal Spirits Demonstrated p. 80 That they are in Motion through the Nerves p. 89 The Nature of them p. 91 The Reason of the Heat of the Blood explained p. 94 That Reason of it's Heat prov'd p. 100 By Attrition p. 103 How the Animal Spirits rarify the Blood p. 111 Why the Heat varies p. 112 How Sp. of C. C. raises the Pulse p. 116 The Reason of flushing Heats p. 120 How far the Blood and Spirits are Active and Passive p. 131 How the Heat of the Blood is continued p. 132 Some Objections answered p. 134 Why it's Heat declines p. 139 Of the Use of the Lungs p. 159 In Respect of the Soul p. 162 Why they
sulphureous oyly Matter is farther manifest by exposing the Brains of any Animal to the Air because they presently grow rancid and fetid It appearing then that the Animal Spirits are an oyly mucilaginous Substance abounding with the most volatile Salts and Sulphurs of the Blood and that they are in a continual Circulation from the Brain and spinal Marrow through the Branches of the Nerves and that being forcibly laid down in the Glands there meet with the Arterial Blood I shall next endeavour to shew how the Heat of the Blood is carried on and continued which I conceive to be after this Manner These oyly Salino-Sulphureous Spirits being violently driven through the Nerves meet with the Arterial Blood in the Glandules and these two Liquors being forcibly driven one against another the Particles of them are intimately mixed together by which means the Animal Spirits are as if it were ground and rubbed betwixt the fixed and more solid Particles of the Blood whereby they are minutely dissolv'd and being put into a swift intestin Motion they endavour powerfully to expand themselves and to fly away but being held in and reverberated by those grosser Particles their Motion is by that means inverted and that Force which if they had but Liberty would be lost in a further Expansion being inverted and driven forcibly upon the other Particles they mutually increase and promote one anothers Motion by which Motion the Blood when it affects our Sensory causes us to perceive Heat In carrying on of which it is to be observ'd that the Animal Spirits being thus accidentally expanded and put into Motion by the grosser Parts of the Blood and being thus held in and struck back by them does not only by that Means fly back and increase each others Motion but also hurry the grosser Particles of the Blood along with them and so increase their Motion and by striking against them and knoking them together break them as if it were into smaller Parts and consequently ratify and expand Them also It is further to be observed that as these Spirits are more or less in quantity so the gross Parts of the Blood grinding them together and putting them in Motion they more powerfully or less vigorously expand and moving accordingly digest and rarify the Mass of Blood to a higher or lower Degree and consequently put the Parts of it into a stronger or weaker Motion We may further take Notice also that the sharper the Particles of the Blood are so they corrode and grind the Spirits into Parts with greater Violence and consequently sharpen their Motion Again when the Mass of Blood is very full of and plentifully abounds with volatile Salts Sulphur the Particles of it are with less difficulty put into Motion by the Spirits and joyning with them encrease their Motion and on the contrary when the Mass of Blood is more dull and phlegmatic it neither so powerfully grinds the Animal Spirits nor is so easily put into Motion it self Furthermore The Animal Spirits do not only according to their different Quantities differently exagitate the Mass of Blood but also according to their different Degrees of Activity whence the more volatile and stronger the Spirits are the more conspicuous are their Effects Lastly we may take Notice that neither the Animal Spirits nor the Mass of Blood are altogether Active or Passive in producing these Effects but mutually both of them and by Turns Having premised this short Account of the Heat of the Blood without any manner of Proof to the end that we might have a more clear and entire View how it was caused without the Interruptions it would have made to prove every Paragraph as I proposed it I shall now proceed to a Proof of what I have proposed collectively for the Material Formal and Efficient Causes of it And First That the Animal Spirits and Arterial Blood are both forcibly laid down in the Glandules I have given sufficient Reasons to evince in my Treatise of Muscular Motion and have given further Proof of it here To prove then that the Heat of the Blood does proceed from that Fermentation it being necessary to explain the mechanical Motion of the Parts of those Liquors that work mutually one upon another I shall in the next Place shew that the Heat of the Blood is caused by such a mechanical Motion of Parts as I have before mentioned That the Animal Spirits then are forcibly driven against the Arterial Blood is so self evident that it needs no Proof and if so it must needs follow that the Particles of the one will be intimately mixed with the other and it is undeniably True that the Animal Spirits will by that means be ground and rubbed betwixt the Particles of the Blood which are in Motion and amongst which they are mixed and the Animal Spirits being of an oyly Salino-Sulphureous Nature will consequently be expanded and rarified and put by that means into a swifter degree of Motion is evident whether we consider the Effects that solid or liquid Substances have on one another when in Motion for Amber by a violent Attrition of it's Parts against a woollen Cloath feels hot the Sulphureous fat Effluviums being by that Attrition encreased and caused to fly out in greater Quantities It is evident also by striking of a piece of Flint against Steel that the sulphureous Particles of the Flint being as if it were disyok'd from the Embraces of the more firm and solid Particles of the Stone and being rubbed and ground betwixt them are put into a violent Motion which causes them so much to rarify and expand that whenever they affect our Sensory they cause that Sensation we call Heat which is accordingly violent as their degrees of Motion are more or less intense and so Amber by a mild Attrition is moderately warm and by a violenter more sensible Again It is observable in the turning of any large and weighty Wheel where the extraordinary Weight makes such a forcible Pressure of those Parts that lie about the Axle-tree that by strong and frequent Attritions of the Parts together the crude Sulphur which is fettered up in the Substance of the Wood is by degrees loosned and dissolved and being put into Motion is rarified and expanded which being still ground betwixt the solider Parts of the Wood it's Parts are yet put into so strong a Motion that they break and dissolve that solid Substance and by creating a Flame consume and burn it In like manner the Particles of Fire being applyed to Gunpowder by dissolving and grinding of it's Parts in Pieces and putting them into a violent Motion cause them to expand and explode But not only solid Bodies cause Heat by grinding of volatile sulphureous Particles betwixt them and so by putting them into Motion but also the Patticles of Liquids by grinding one upon another put themselves into so violent a Motion as not only to cause Heat but
sometimes so high a degree of it as actual Flame as when Spirit of Wine and Oyl of Turpentine are mixed together And that Heat proceeds from an Attrition of sulphureous Particles and their violent Motion I have not only brought Instances enough to make it appear but have sufficiently proved it before in my Answer to Dr. Willis's Opinion And now since not only Solid but also Liquid Bodies grow hot by an Attrition of their more volatile and sulphureous Particles betwixt the more gross ones and since there appears from what I have before said but one way by which all Bodies grow hot we must needs conclude that the volatile salino-sulphureous Particles of the Spirits grow hot by being ground betwixt the grosser Particles of Arterial Blood and that those by putting the whole Mass into a more violent Agitation cause the Heat of the Blood But some will perhaps say that in all those Phaenomena I have mentioned these grosser Parts of Matter which grind upon the sulphureous Particles are put into Motion by something else But they do not perceive how the grosser Parts of the Blood are put into Motion first To which I answer that the Particles of the Mass of Blood are put into Motion by that force which is always inseparably joyn'd with Circulation so that in a Man's Body as there is a continual Circulation of Humours so there is of Causes for the Fermentation in the musculous Glands is raised by the Mass of Blood grinding the Animal Spirits betwixt the Parts of it in which Fermentation a subtile Liquor is prepared which being forced into the Fibres of the Heart cause it to contract which Contraction forces the Blood and consequently the Nervous Juice through their distinct Vessels and so causes them again to meet and ferment a second time in the Glandules and as Circulation is preserved and carried on by the subtile Liquor which is continually prepared in this Fermentation so the Particles of the Blood are mixed with the Spirits and preserved in Motion by Circulation Having thus shew'd that the Heat of the Blood may as probably proceed from Attrition as Heat in any other Bodies since Heat is nothing else in respect of that which causes the Sensation than a quick intestin Motion of Parts and since those can be put into Motion no other way but by Attrition I should in the next Place prove that the Particles of refined and rarified Matter always expand and endeavour to fly away but being reverberated by the Opposition of those gross ones with which they swim their Motion is inverted and by that means much increased But it is so evidently True that it needs not for we always observe that where any two Bodies meet together and strike against one another that which is less yields to that which is most solid and makes the strongest Opposition this is manifest in Flame it self as also in the Expansion of Gunpowder for if a Gun be shot against a Wall the Flame of the expanded Gun-powder striking against it presently flyes back again and by mixing with that which immediately follows it encreaseth the force of it and for this Reason a Gun which is charged with a greater weight of Shot more forcibly recoils the Powder not finding free Liberty to expand but flying backward with a greater Force It is also further evident from the Reason which I have given why Nitre is beneficial-in continuing Flame and making it more vigorous The gross Parts of the Blood having thus put the Animal Spirits into a swift Motion and by inverting them in their Motion having caused them to encrease one anothers Motion the Spirits at last set upon the Mass of Blood and by breaking and dissolving the Particles of it rarifie them and cause them to expand also so the Rays of the Sun being in a swift Motion and gathered into a Point by a burning Glass grow more vigorous so as to dissolve and burn even solid Bodies and after the like manner Flame by the force of it subtilizeth and attenuates the Sulphureous Parts of it's Fuel neither does it only rarifie and expand the Sulphureous Matter of it's Fuel but also carries violently the Ashes of the calcined Matter along with it where it may be observed that as the Particles of Animal Spirits are not in so strong a Motion as those of Fire so the Particles of the Blood are moved with a more easie force then Ashes which are far more Solid But for a further Proof that the Mass of Blood grows hot in a Natural state by the Methods and Ways which I have endeavoured to explain I shall in the next place prove that the Animal Spirits being put into Motion according to their different Quantities differently expand themselves and exagitate the Mass of Blood and put it's Parts in a more violent or weaker Motion and consequently encrease or diminish the Heat of it And this is easily manifest if we do but observe that young healthful People whose Nerves as well as the Fountains from whence they spring are full of and abound with Spirits are always of a more brisk and vigorous Heat then People of a declining Age whose Nerves are less plentifully stocked with them But it is not only observable in People of different Ages but also in different Constitutions that as the Pabulum of the Animal Spirits is more plentiful and yields a more constant and large Supply so the Heat of the Blood is more powerful and intense as in cold and Phlegmatick Constitutions where the Mass of Blood abounds with dull Phlegmatick Humours or Acid and Austere Juices of too close and compact Texture and a large Supply of Spirits is denyed the Blood is not of so hot a Temper as in Cholerick Constitutions whence it evidently appears that the Heat of the Blood depends on the Vigour of the Animal Spirits for if when the Vessels are filled with Spirits and plentifully supply the Glands that Fermentation is raised higher and by that means the Heat of the Blood is accordingly encreased it is a most certain Conclusion that the Heat of the Blood depends upon the Effects that the Animal Spirits have in that Fermentation Which is further confirmed by the common and constant Practice of all Physitians for when the Natural Heat as some call it is languid and weak and almost extinguished they give such Medicines as increase the Heat of the Blood by renuing the Vigour of the Spirits whence to People that are almost a dying their Spirits being dulled or exhausted nothing is more usual then to give them Spirits of Harts-horn or of Armonick-salt or some other Saline or Sulphureous Spirits which presently joyning with those in the Nerves encrease the Fermentation in the Glands and by that means put the Mass of Blood into a more swift Exagitation and by raising the Fermentation not only renue Circulation but the Heat of the Blood On the contrary when the
except by hindring the fierce volatile Parts which ought to be dissipated from flying away through the Pores of the Skin which being increased thereby to too great a Quantity exagitate the Mass of Blood too much From hence it breifly yet plainly appears that the Nitre of the Air alters the Colour of the Blood and also serves to temper the Heat of it I shall now consider what Effects it hath upon the serous Lympha and if we may but compare it to Milk which differs only from Chyle by being less impregnated with Oyl it will be manifest that it precipitates the Watry Parts of the Serum which joyning with the fixed Salts of the Blood dispose them to be separated and carryed off by the Urinary Passages This is so strongly proved both by Non-Naturals and Medicine that to deny it would be to contradict Reason and plead Ignorance of those Things it is almost impossible for us not to take notice of for if we sit by a Fire in a close warm Room and drink a good Quantity of Beer which is not very strong it presently if we go into the cold Air runs off by Urin besides nothing in Medicine is a more known and common Diuretick than Sal. Prunel which is purified Nitre concentered and condensed and it is no less observable in an Experimental Observation of the Famous Dr. Lower's who in his Book de Corde takes notice that as much Serum is precipitated in a short time after we rise from Bed as in the whole night when we are less affected with the ambient Air. How Beneficial Nitre is in Precipitating the Serum of the Blood and what Advantages the Animal Oeconomy receives thereby I shall not now enquire yet how inconsiderable a Part of it's Office soever it may seem yet if it be duly weighed it will appear very useful From what I have said concerning the Alterations made on the Blood and it 's Serum I should now proceed to consider how they influence each other but since as much as is sufficient for our present Purpose may be gathered from what hath gone before it being plain that the cool Serum will help to temper the Heat of the Blood and vice versa I shall wave a further Notice of it here and should rather shew That The Lungs perform many more and considerable Offices in respect of each Part But to explain them would not only be to treat of the Lungs but the whole Body and the Use of all the Parts which being not my present Design I shall omit giving an imperfect Account of them because they are so interwoven mutually with one another that they cannot truly be understood without an Account of the whole FINIS Our Knowledg in Philosophy is limited to a small Part of the Creation Which is furnished with Objects too copious for our Senses Of which at the best we have but an imperfect Knowledg The Pursuit of Knowledg very desirable Especially of that which is most Advantagious There is more Reason to expect Truth and Certainty in the Microcosm than the Macrocosm Where it is easily attained The Heat of the Blood not obscure in respect of it's Cause Both Antients and Moderns have differed as to the Cause of it The Opinions of the Antients very Superficial and Insatisfactory Dr. Willis ' s Opinion considered Who asserts that there are three ways by which Liquids grow hot And that the Blood grows Hot by Accension To which it is answered that there is but one way in Philosophy by which all things grow hot Several degrees of Heat differ only in Degrees of a peculiar Power to cause Heat And Fire which is the highest is rarified Matter in a swift Motion which Masked in different Subjects affects not our Sight Heat is not actually in the Body that causes it but potentially because that Body hath a power to cause such a Sensation Heat is only a Sensation which is actually where there is Sense to perceive it That Heat is only produced one way further proved Viz. by putting the Parts of Matter into Motion A seeming Objection answered His Comparison of the Bloods Accension with Flame considered There are several degrees of Heat produced without visible Flame Nitre makes up no part of the Flame The Nitrous parts of the Air promote Flame by keeping i'ts Matter from dispersing too soon Wherefore Fire burns better in the Winter than in the Summer Why a Candle in a Glass Globe is extinguished by extracting the Air. His Comparison of extinguished Flame compared with the Death of an Animal considered Nitre does not promote the Heat of the Blood but rather depresses For in Liquids the volatile Parts are sufficiently opposed by the Parts of the Blood and kept from flying away Blood may grow hot without a Sulphureous Pabulum His Comparison of the Recrements of Flame and of Blood considered Which appears widely inconsistent First because that Juice that sweats through the Coats of the Trachea and the Skin is not Recrementitious And the Fuliginous Effluviums of Fire are Recrements Secondly because the former if not carried of encrease it But Smoak extinguishes Fire Smoak is not altogether an Effluvium of Flame Smoak thus compounded A Digression in which is given the Reason why Flame Ascends rather then Descends Which is because it hath less Opposition in it's Motion that way Because the Air the nearer to the Center makes stronger Opposition than that above Which is proved by these Experiments It is also proved by the Expansion of Gunpowder The Motion of Flame downwards is a natural Motion in Philosophy Diemerbroek's Opinion examined Dr. Henshaw ' s Opinion considered Antient and Modern Writers have rather disputed about the Vse of Words than much difference observable in their Opinions The Reason why Heat affects our Sensory does not shew how it comes by that Power The Blood grows hot by Attrition the Consequence of which is Fermentation Attrition and the consequence of it both to be signified by the Word Fermentation How far the Heat of the Blood proceeds from Pressure and Mixture To dispute about Words is not material in an Enquity after the causes of Things The whole Body is made up of Vessels and Humors contained in them By what means the Spirits and Blood are mixed in order â—o a Fermentation Animal Spirits demonstrated In the substance of the Brain Viz. that Mucilaginous oily Moisture which we call Brains An Objection Answered That it is the most spirituous Part of the Blood and consequently Animal Spirits proved That oyly Substance is capable of performing all those Actions which we can suppose the Animal Spirits do Another Objection answered That these Spirits are in a constant Motion proved The Nature of the Animal Spirits considered The Reason of the Heat of the Blood explained How it's Heat is promoted The Heat of the Blood varies according to the different Quantities of them It varies also according to the sharpness of those Humors that put the Animal Spirits
into Motion The volatile Salts and Sulphurs in the Mass of Blood make it more apt to be fermented Which is more or less promoted according to the different Degrees of the Activity of the Spirits Neither the Animal Spirits nor Arterial Blood are wholy Active or Passive That the Heat of the Blood proceeds from Fermentation proved That Heat proceeds from Attrition further proved Not only solid Bodies but also Liquids grow hot by an Attrition of their Particles The Particles of 〈◊〉 of these Humours are first put into Motion by Circulation That the Particles of refined and rarified Matter are by an Inversion of their Motion put into a higher degree of it proved How the Animal Spirits rarifie the Blood That the Animal Spirits according to their different quantities differently exagitate the Mass of Blood prov'd By the observation of People of different Ages As also by different Constitutions And the Practical Part of Physick How Spirit of Harts-horn raises the Pulse That the Spirits according to their different Degrees of Activity variously exagitate the Mass of Blood The sharper the Particles of Blood are the more they corrode the Spirits and put them into Motion The Keason of flushing heats in the Scurvy Proved by comparing the Nature of the Medicines that oppose it and correct it That as the Blood as more or less Volatile it's Parts are put more or less easily into Motion proved And that it is differently promoted according to teir different Degrees of Activity of the Spirits How far the Blood and Spirits are Active or Passive How the Heat of the Blood is continued Some Objections considered and answered The first Objection answered viz. whether the Heat of the Blood be chiefly caused in the Extremities of the Vessels The Reason why the Heat of the Blood in time decays And that Reason proved How Fermentation is carried on in a dying Body and the Reason why it ceaseth when it is quite dead Another Argument to prove that the Heat of the Blood depends on and is caused by Attrition Fermentation Circulation mutually depend on one another The second Objection answered viz. That Fermentation may be performed in so short a time as the Circulation of the Blood admits The Blood is more powerfully fermented in the substance of the Heart than in any proportionable Part of the Body besides Fermentation is not only promoted in the Muscular Parts but also in the internal Bowels Three things requisite to continue the Heat of the Blood The Vse of the Lungs in Respect of the Soul Is to express all it's Conceptions and Reasoning Why the Lungs ought to be in a continual Motion is because It carries off that Superfluous Moisture that supplies them And that their voluntary Motion might less Preternaturally affect our Bodies What Effects it causes when too thick and also why thick foggy Air is troublesom to some People The Vse of the Lungs in respect of the Body Seems to be to perform the Office of another Heart By helping the Blood to force violently enough into the Cavities to distend them against the next Contraction How stopping the Breath of an Animal kills it Why by permitting it to breath again the Circulation of the Blood is renued How the Motion of the Heart is promoted in an Infant unborn The Office of the Lungs is partly voluntary partly involuntary What Effects the Air hath upon the Mass of Blood In respect of it's Colour Nitre depresses the Heat of the Blood What effects Nitre hath upon the Serum of the Blood