B H * $1 k - ,n -c * .wo* CYK j)S8 Columbia intijeCttptfltogark LIBRARY DISSERTATION ON THE PATHOLOGY OF THE HUMAN FLUIDS Digitized by the Internet Archive in 2010 with funding from Open Knowledge Commons http://www.archive.org/details/inauguraldissertOOdyck /X~ e* t***^. INAUGURAL DISSERTATION THE PATHOL OG Y OF THE HUMAN FLUIDS BY JACOB DYCKMAN, A. B. MEMBER OF THE MEDICAL AND SURGICAL SOCIETY OF THE UNIVERSITY OF NEW-YORK. Nee vitE solum sanguis autor est ; sed pro ejus vario discrimine, sanitatis etiam, snorborumque causae contingunt, Harvey. NEW-YORK: PRINTED FOR THE AUTHOR BY VAN WINKLE AND WILEY S Corner of Wall and New-streets. 1814 - AN INAUGURAL DISSERTATION ON THE PATHOLOGY OF THE HUMAN FLUIDS. SUBMITTED TO THE PUBLIC EXAMINATION OF THE j^/ — TRUSTEES OP THE COLLEGE OF PHYSICIANS AND SURGEONS OF THE UNIVERSITY OF THE STATE OF NEW-YORK, SAMUEL BARD, M. D. PRESIDENT, FOR THE Degree of Doctor of Medicine, On the 4th day of May, 1813. 70 e J TO DAVID HOSACK, M. D. F» L. S. LONDON ; Frofessor of the Theory and Practice of Physic and Clinical Medicine in the University of the State of New- York; Vice President of the Literary and Phi- losophical Society of New York; Fellow of the American Philosophical Society, and of the College of Physicians at Philadelphia; Member of the Literary and Philosophical Society of Preston; Honorary Member of the Royal Medical and Physical Societies of Edinburgh ; Corresponding Member of the Medical So- ciety of London, and of the Massachusetts Historical Society, S{c. Sir, To you I dedicate the following Dissertation. With much pleasure I embrace the present opportunity of acknowledging the obligations, which have arisen from a long and faithful course of instruction, imparted to me in your private medical school ; and most cheerfully do I thus make public those feelings of gratitude and personal regard which I have ever cherished since the relationship of pre- ceptor and pupil has existed between us. But, independent of these considerations, I know no one to whom with so much propriety these pages can be inscribed as to you. They are written in support of those fundamental principles which have been inculcated by the most eminent philo- Vlll sophers who have adorned the science of medicine, and which you, Sir, in your professorial lectures in the University, have illustrated with distinguished ability and success. Convinced, as I am, that these principles are founded in truth, and will lead in their consequence to important results in practice, I have endeavoured to adduce such additional proofs in their support as some small share of reading and observation have enabled me to offer. Should you do me the honour to approve this little essay, it will aiford me the most ample and satisfactory compensation for all my labours. With sentiments of the highest respect and esteem, I remain, Sir, Your friend and humble servant, JACOB DYCKMAN TO JOHN W. FRANCIS, M. D. Professor of Materia Medica in the University of Vie State of New-York ; Member of the Society for the Promotion of Useful Arts in the State of New- York, and of the New- York Historical Society; Corresponding Member of the Massachu- setts Historical Society ; Fellow of the Literary and Philosophical Society of New-York, fyc. Sir, I have prefixed your name to this performance, in commemoration of the friendship which has, for many years, existed between us, and as a testimony of the respect which I entertain for your professional standing, and of that esteem I cherish for the uniform integrity and purity of your moral character. Permit me here to express the wish, that your success in promoting the best interests of that liberal and en- lightened profession of which you are a member, may be commensurate with your talents and unremitted exer- tions ; and that the career so auspiciously commenced may remain unchecked by misfortune or reverse. In perfect sincerity, and with sentiments of the truest per- sonal regard, I subscribe myself Your friend, J. DYCKMAN. 2 PREFACE, The object of the following Dissertation is to exhi- bit a concise and systematic Pathology of the Human Fluids, or a view of their various morbid affections, with their differences, causes, and effects. The present inquiry relates more especially to the blood, or vital fluid, which is not only universally distributed throughout the body, but is the source from which all the other humours are derived. When the blood, therefore, becomes viti- ated, the secretions will necessarily partake of the affec- tion. All the disorders of the fluids, considered in themselves, have a reference either to their quantity or their quality. The subject matter of these pages has, accordingly, been arranged under two general divisions : the first of which embraces the morbid qualities of the fluids. These, again, may be comprised under three heads ; morbid fluidity, acrimony, and putrescency. The second relates to the morbid quantity of the fluids; under which head are considered the doctrines of Plethora. Xli PREFACE. Iu perusing the following pages, it will be seen, that the author has made constant reference to the writings which he has consulted. His motive in so doing was not only to give credit to the intellectual labours of others, but also to present the original authorities upon which any facts and opinions are supported, and to direct the reader to any further illustration which they may afford. It may here be proper to remark, that the present Dis- sertation was originally submitted, in manuscript, to the examination of the Trustees of the College of Physicians and Surgeons, in May, 1813, for the purpose of receiving the honours of the medical doctorate in the University of New-York. Believing the doctrines which he then at- tempted to maintain, to be founded on well-known physio- logical and pathological principles, and eminently calcu- lated to advance the practical interests of the profession, the author was afterwards induced to enter more fully into an illustration and defence of the tenets he had espoused. It would be unnecessary here to offer the various rea- sons that have induced the author to adopt the opinions attempted to be supported in the following pages. His reasons are, with more propriety, unfolded in the course of the work. When he first entered upon the consideration of this inquiry, he entertained no particular sentiments concerning the result. He owes his convic- tion of the truth and practical importance of the prin- PREFACE. Xlli ciples he now supports, to a patient investigation of the subject, and, he believes, to an impartial and unpreju- diced examination of facts, and of the observations and opinions of the most approved writers. Of the numerous topics of pathological investigation, few are more deserving attention than the doctrine of the fluids ; and from the manner in which the inquiry has been conducted, none, perhaps, has afforded more abundant room for animadversion. Hence, whether the solids or fluids are primarily affected, and how far these latter are ever the subject of disease, are questions which have been discussed in all the bitterness of controversy. Discus- sion, though in an eminent degree calculated to lead to the discovery and development of truth, loses much of its importance in this respect, when influenced by preju- dice, or by passion. " Science disdains the spirit of party, and philosophy herself weeps at the madness of secta- rians."* The author must again repeat, that he cannot but be- lieve that the doctrines attempted to be supported in the present performance, as they are founded upon a general, and not a partial view of the human fabric, will lead to consequences the most auspicious to humanity. Empires and science are subject alike to revolution, and as the for- * Dr. John W. Francis. Xiv PREFACE. mer, after being the victim of usurpation, not unfrequently again revert to legitimate dominion, so is it incident to the latter to revive those well grounded truths which may have been exploded by the fashionable theories, or the prevailing philosophy, of the day. It may here, too, be observed, such has been the force of authority since tho appearance of the systematic writings of Cdllen, and still more lately, those of Brown, Darwin, and their disciples, that the teachers in the most celebrated schools of medicine have been wholly regardless of the fluids as a constituent and essential part of the animal economy. May the author be permitted to add, that the honour of restoring this pa- thological principle, as founded upon the most prominent facts which the science affords, and the most striking re- sults which animal chemistry presents, has been reserved for this country, and for the present teacher of the Theory and Practice of Physic in the University of New-York. THE AUTHOR. New-York, March 4, 1814. CONTENTS, PAGE Preface, H Introduction, . 17 ON THE MORBID QUALITIES OF THE FLUIDS. Natural History of the Blood, „ 36 Morbid Fluidity of the Blood, ..... 68 Morbid Acrimonies of the Blood, .... 93 Dissolved and Putrescent State of the Blood, . . 13S Action of Specific Morbid Poisons, . . . . 184 ON THE MORBID QUANTITY OF THE FLUIDS. Plethora, ......... 200 Diseases of Plethora, . . " " ■ . . . . 225 DISSERTATION ON HE PATHOLOGY OP THE HUMAN FLUIDS., 1JVTR OJD UCTION. To explore the nature and causes of disease; to trace their operation upon the animal ma- chine ; to determine those morbific dispositions of body which must concur with the remote or possible causes before any one general symptom of disease can take place; to ascertain the changes or conditions in the state of the corpo- real frame which are essential to, and invariably productive of, the different species of morbid, affections, is one of the most important, and, at the same time, one of the most difficult under- takings in the whole science of medicine^ 3 1# PATHOLOGY OF THE Many are the ingenious theories and hypothe- ses, many the plausible systems that have been formed on this subject, and which have been successively published from the earliest periods of physic down to the present time. Of these several systems, each has had its votaries, who have for a time supported its credit, and given to its doctrines a gay and flourishing appear- ance ; but they have at length yielded to others more novel, or more captivating, or, perhaps, better fitted to the state of medicine, and to the prevailing philosophy of the age. Such has uniformly been the fate of nearly all the various doctrines of medicine that have as yet been offered to the world; principally from their having been the offspring of conjecture, without the support of facts and observations, the only grounds and principles of all true and rational philosophy. But this solid foundation appears to be w r anting in most of the several systems of physic hitherto invented ; of conse- quence, time betrays their weakness, and they fail of themselves to ruin. The philosophy of the ancients, indeed, was so extremely limited with regard to our internal economy, or the HUMAN FLUIDS. 19 laws by which our animated system is governed, that they had not sufficient data for establish- ing any thing of a general pathology explanatory of the various morbid conditions of the human frame. And the moderns, notwithstanding their superior advantages, and the favourable turn to our medical philosophy, have not made such advances as might have been expected. We are still greatly in the dark with regard to the in- ternal economy, over many of the operations of w T hich nature appears to have drawn an im- penetrable veil. The whole material world has been, not im- properly, divided into solids and fluids, as being the only essential states of matter we are able to observe. In compliance with the mode of expression usual among medical writers, the corporeal part of man may be said to be com- posed of both these conditions of matter, being nothing else but a fine contexture of solids and fluids, which are tilted by the laws of nature for different purposes, and by their various motions are productive of all the phenomena of animal 20 PATHOLOGY OF THE life.* And in correspondence with the views which physicians of different ages of the world have taken of the animal body, and of the influence which these two component parts were supposed to exert upon the organized living system, the seat and cause of disease have, at different periods, been almost exclusive- ly referred either to the solids or to the fluids. But, as an ingenious authorf has observed, there are fashions in physic as well as in every thing else, and it is to be regretted that in our transition from one theory to another, we run too much into extremes. For here it falls out, as in most other disputations, we err in carrying things too far. The humoral pathology, as it is called, under various modifications, prevailed universally in the schools of physic for a great length of time. Diseases were supposed to have * Corpus humanum constat e partibus solidis etfluidis, quarum mutua actione, functiones vivi hominis (quatenus corporeee sint) peraguntur. Gregory, Conspectus Medicinw, ^ 69. i Walker, An Inquiry into the Small Pox, p. 59. HUMAN FLUIDS. 21 their seat chiefly, if not entirely, in the animal fluids or humours; and to their changes or dis- ordered conditions were principally attributed all morbid phenomena. This doctrine, or opinion, notwithstanding it gave a very impro- per and fallacious idea of many diseases, was so generally received, and so warmly espoused, that although others were occasionally pro- posed, they were, by the generality of physi- cians, considered only as innovations, and were, in general, but of short duration. Of late, however, the opposite doctrine ap- pears to have been generally received, and it has now become fashionable to refer all morbid phenomena to the different affections or condi- tions of the solids, without any regard to the influence of the living and circulating humours. The respective writings of Willis* and Bag- Livif seem to have given the first hint, that a consideration of the different affections or con- ditions of the living solids, would, in general, * Pathologia Cerebri et Nervorum. f De fibra motrici et morbosa. 22 PATHOLOGY OF THE afford the most probable grounds of disease, and a more rational and satisfactory explana- tion of many morbid phenomena, than that of the derangements or disordered conditions of the animal fluids. The celebrated Hoffman,^ however, was the first who put physicians in the proper train of investigation, reduced this doctrine to any tolerably clear and simple form, and satisfactorily pointed out any extensive application of it in the explanation of diseases, or in unfolding the various occurrences in the morbid conditions of the animal body. But it is in the w 7 ritings of the learned and ingenious CuLLENf that a far more bold and general ap- peal is made to the agency of the living solids., or moving powers of the body, and their various affections, as constituting the essence of much the greater number of diseases. And, lastly, in the systematic works of Brown J and Dar- win,$ all consideration of the changes or condi- * Medicin. Rational. System, torn. 3. sect. i. cap. 4. f First Lines. X Elementa Medicina?. ^> Zoonomia, or the Laws of Organic Life. 1 HUMAN FLUIDS. 23 lions of the humours, as the origin of disease, is wholly rejected, and the phenomena of life, whether in a state of health or disease, are ex- clusively referred to the various action of the moving fibres, and to the agency of the nervous energy, or sensorial power, resident in the living solids. From a due consideration of the nature, func- tions, and composition of the living human body, to us it appears that these two opposite doc- trines, namely, that of the fluids and that of the solids, have both been carried too far ; and while one party have supported one opinion, and the other the very reverse, the probability is, that no disease of the constitution can take place without involving every part of our system, af< fecting the condition of the solids as well as that of the fluids. For such is the universal sym- pathy, and such the continual intercourse inces- santly kept up between these component parts of our body, that in health they mutually assist and support each other, and are fitted by the Jaws of nature for the different purposes of the animal economy ; in like manner, in the morbid 24 PATHOLOGY OF THE state they sympathize together, and reciprocally communicate their affections. By the human body we are to understand, what it really is, a whole, in which the various parts have different and various properties, which compel them to act in conformity to these same properties, and which keep them in perpetual action and reaction on each other. Its various instruments and powers are but parts of one stupendous whole, and so intimately con- nected, and so mutually influencing the actions and conditions of each other, as to produce but one continued and perpetual circle of motions, some of which are influenced by others, and could never be completed without all their parts or instruments being duly arranged, and in their proper places. For example, the blood, which is the primogenial part of the animal embryo,* is the first cause that excites the heart into ac- tion,! and by its perpetual stimulus or impression, * Harvey, De Generatione Animalium. f Certumque est, visiculam dictam, ut et cordis auriculam postea, (unde pulsatio primum incipit) a distendente sanguine, ad constrictionis motum irritari. Ibid. Exercit. 51. HUMAN FLUIDS. 25 forever after determines and keeps up the mo- tions of this organ. 1 * And again, the heart it- self borrows its motory power from the nervous energy, which latter presupposes the circulation of the blood, and its constant impression upon the brain and spinal marrow. And so of all the other principal parts of our system. Hence the beauty and perfection of the animal circle! The living and moving solids, by their energies and action, propel the blood and humours, and preserve them in a renovated and healthy state, whilst these again, by stimulating the vessels which contain them, keep up their due and ne- cessary motions, and at the same time are fraught with what is necessary to replace the various expenditures of the system, whether of sub- stance, vigour, or vitality. Hence the truth of what is so beautifully observed by Hippo- * Qui hos experimentorum nostrorum eventus pensitaverit, is quidem non dubitabit nobiscum pronunciare, causam, quae cor in motum ciet, omnino sanguinem venosum esse: nam enata ea causa cor movetur, subtracta quiescit, diminuta motus cordis languet, aucta motus intenditur. Haller, Elem. Physiol. Corp, Hum. torn. i. p. 495. 4 26 PATHOLOGY OF THE crates, that " every thing in the human body is so disposed in manner of a circle, that you will find the end where you would look for the beginning, and the beginning where one might expect the end."* But, notwithstanding all the several powers and instruments of the body are necessary to the energy and uniform operations of the whole, yet certain parts thereof seem to hold a primary, and others a subordinate importance. Sensation and the circulation of the blood are the last signs of life ; and life itself, according to a celebrated French physiologist,! is produced by an impression of the arterial blood made upon the brain and medulla spinalis, or a princi- ple resulting from that impression. The ner- vous and vascular systems may, therefore, be esteemed the prime essentials of life, and the immediate cause of the animal motions; and, of * EjCto) S~ox,iit dgyjn y.iv ovv ovfif/.iet tivett tov "X si/gs6w. He Locis in Homine. ■}■ Le Gallois. HUMAN FLUIDS. 27 consequence, the consideration of these will always form the leading doctrines of true and rational pathology. From what has been said in the preceding pages, it appears that the animal body is a machine, delicate in its texture, consisting of solids and fluids, which, by their various pro- perties and mode of action, are productive of all that peculiar assemblage of motion which constitutes life; and that health itself consists in the regular and equable motions of these com- ponent parts, together with proper conditions thereof; and that diseases are their aberrations. From this general, though imperfect, view of the animal economy, it is easy to apprehend that the animal motions may be disordered, and diseases brought on by a great variety of causes: for whatever too much increases or diminishes the nervous or vital energy ; what- ever too much excites or depresses the actions of the moving fibres; whatever renders the fibres too dry, elastic, and tense, or too moist, flaccid, and weak; whatever over and 28 PATHOLOGY OF THE above increases or diminishes the quantity of circulating humours; whatever renders the blood too dense, thick, and viscid, or too thin, limpid, and serous; whatever loads and im- pregnates this fluid with too large a proportion of active, acrid, putrescent particles, or with too many sluggish, poor, and watery corpuscles; whatever creates in the humours a tendency towards an alkaline, or putrescent disposi- tion; whatever inordinately promotes or re- tards any of the secretions or excretions ; and, lastly, whatever increases or diminishes the force or velocity of the circulation, or augments or rebates the vital heat and energy of the body, beyond a certain degree, will affect or disturb the animal motions, and thus become the pri- mary and immediate ^cause of some disease or other. Seeing, then, the various changes in the habit whence disorders may proceed, it would seem surprising that diseases are not more fre- quent, or that the animal body should be able to hold out to extreme old age. But we are to recollect " that nature assumes some latitude in HUMAN FLUIDS. 29 her operation? without injury to the body,"* and therefore, as Galen| has well remarked, what is called health, is neither absolute nor indivisi- ble, but admits of considerable latitude ; by vir- tue of which the solitary alienation of any one part, or small deviations from the natural stand- ard of health, seldom affect the integrity of the functions ; so that disease only breaks out at last when the evil has become more considerable^ and been more widely diffused.^ To the pro- duction of disease, therefore, as physicians justly affirm, there is required a particular combination of causes^ no single one, however powerful, being sufficient for this purpose, without the concurrence of others: and yet that which alone * Gardiner, Observations on the Animal Economy, p. 17„ f Hon enim absoluta ipsa est, nee indivisibilis simul, quae est et dicitur sanitas, verum etiam quae ab hac deficit, modo adhuc usibus nostris non sit inepta. Galen, De Sanitate tuenda. $ Inest etiam in sanitate robur aliquod, quo se adversus vitia singularia tuetur, nee a solitaria cujusvis partis alienatione func- tionum suarum tenorem mox perturbari sinit : ut adeo plerura- que morbus turn demum erumpat, cum latius se diffudit malum* Gaubii Pathologia, ^ 123. ^ Blane, Diseases of Seamen. 30 PATHOLOGY OF THE produces no visible effect, as Celsus observes* often proves extremely efficacious in conjunc- tion with others ; so that we in general adjudge that to be the cause of a disease which appa- rently most contributes to its production.* As health consists in a proper harmony and regularity of the animal motions; so disease, on the contrary, is this harmony destroyed, and evidently consists in the production of a new series, a new order of motions and things. To the regulated and necessary actions which con- spire to produce life and health, succeed those determinate actions that concur to produce dis- ease and dissolution. But all the animal mo- tions are the result of the joint influence and co- operation of the different solids and fluids of the body ; and therefore it is in the changes or dis- ordered conditions of either the one or the other, or of both these, that we are to look for * Nihil omnino ob unam causam fieri, sed id pro causa appre- hendi, quod contulisse plurimum videtur. Potest autem id, dum solum est, non movere, quod junctum aliis masime movet hi Pmfat. lib. i. p. 16. Ed. 1730. HUMAN FLUIDS, 31 the causes of disease. The various affections of the living and inert solids, it is true, will be found to be the cause of disease much more fre- quently than the various state and changes of the several animal fluids ; but this surely is no good reason for rejecting altogether the agency of the latter, or for denying either the possibility of a fault in the humours, or, that they are capa- ble of affecting, by their different condition, the motions or state of the living or inert solids. The blood being the true stimulus to the action of the heart and arteries, it is easy to understand that this fluid will be differently qualified for this purpose, according to the different state of its sensible or chemical properties. Thus, ceteris paribus, a dense, rich blood, will be capable of impressing and receiving the force of the heart and blood vessels more fully, and, consequently, of producing a more general excitement through- out the system, and a higher degree of the vital heat and motions, than a weak, impoverished, or serous blood. It is upon this principle that the learned Haller observes, "Calor cum densi- tate sanguinis increscit, et cum aquosa ejus te- smitate ita minuitur, ut aquosus cruor, etiam ve- 32 PATHOLOGY OF THE hemerter motus, calorem non parem generet, aquae exemplo, quse celerrimo motu levissime intepescit, et feminarum teneriorum, quas neque hysterica? convulsiones, neque febres ad eura gradum calefaciunt, qui in sano agricola nasci- tur.* But it is deemed unnecessary longer to dwell upon the importance of attending to the different states of the blood, and the impressions which they are capable of making upon the ge- neral system. Suffice it to say, that this hu- mour is the primitive principle of all animal substances, the common origin of all the animal solids and fluids; and when it is well consti- tuted, and performs its proper office, conveys life, motion, vigour, nourishment, in a word, health, to every part of the organized machine : so, on the contrary, the mass of blood being vitiated, or disorderly moved, becomes a source of much aggravation to the system, and the cause of many morbid effects. That the blood and other humours of the body are capa- ble of admitting morbid or preternatural quali- ties, is a fact demonstrated by daily experience, * Haller, Elem. Physiol, torn. 2. p. 150. HUMAN FLUIDS, 33 and the uniform observations of physicians of every age and country. The colour, tex- ture, consistence, and other sensible qualities of the blood, are liable to various altera- tions. Sometimes the humours appear to un- dergo decomposition in the body, as in vitro. In the scurvy, in putrid, malignant, pestilential fevers, &c. we observe all the phenomena of a degeneration and complete disunion of the dif- ferent principles that compose the blood, the texture of which in some instances appears to be nearly destroyed. In such cases, it seems as if the vital principle abandoned the government of the corporeal frame, and left the solids and fluids to the destructive action of external agents ; in consequence of which they tend to putrefaction, and become decomposed, as they usually do when separated from the body, or when the principle of life or animality is ex- tinguished. To ascertain these several morbid affections of the blood, with their various causes, signs, and effects, is the object of the following Dissertation. But in conformity with the gene- rally received axiom, Rectum est sui et obliqui, before entering upon the consideration of the 34 PATHOLOGY, &C. pathology or morbid state of this fluid, it will be necessary to offer a few observations on its natural history, and its appearances when in a sound condition ; by comparing with which its qualities and accidents when diseased, it will not be difficult to refer the several vitiations to their proper heads or classes* ON THE MORBID QUALITIES THE FLUIDS. The several vitiations or morbid qualities of the circulating fluids, which we are now to con- sider, will be comprised under one or the other of the following heads; namely, morbid fluidity, acrimony, and putrescency. But before we at- tempt to establish conclusions from the various state of the blood when drawn from diseased persons, we must recollect the appearances which this fluid exhibits as taken from sound persons; and, therefore, previously to entering upon the consideration of its diseases, it may be proper to premise a few observations on its natu- ral and physiological history. 36 PATHOLOGY OF THE Natural History of the Blood. The human blood, in its natural and healthy state, is a fluid possessed of a considerable degree of density and consistence,* has a vis- cid and tenacious feel,f a smell somewhat uri- nous, and peculiarly animal,J and is to the taste sweetish or slightly saline,^ from its containing a small quantity of sea-salt, which is sometimes discernible by the microscope,|| and therefore exists in a free and uncombined state; whence it would appear to be an accidental rather than an essential or constituent part of the blood. But notwithstanding this fluid is somew T hat saltish, yet in its healthy state, uninjured by putrefaction, or too violent a degree of heat, it is neither * "Van Swieten, Comment, in Boerh. Aphor. 5} 1174. f Macbride, Theory and Practice of Physic, p. 7. % Johnson, Animal Chemistry, vol. i. p. 24. ^ Hunter, Treatise on the Blood, Inflam. &c. p. 14. || Haller, First Lines, chap. 5. Boerhaave, Institut. Med, ^ 224. n. 5. HUMAN FLUIDS. 37 alkaline nor acid,* but perfectly bland and temperate,f and without the least sensible acrimony; for if dropped into the eye it gives no pain.J Blood is not so fluid as water, but necessarily possesses a sort of plastic lentor and tenacity. Its specific gravity, according to Mr. Boyle,$ is equal to 1040; but from the more recent expe- riments of the accurate Jurin,|| it is estimated at about 1053. The gravity, as well as the consistence of this fluid, may vary very sensibly in different persons, according to age, sex, con- stitution, season of the year, and a diversity of other circumstances. The colour, texture, and consistence of recent blood is variously affected by different re- agents. Its fluidity is increased by alkalis both * Schwenke, Hasmatologia, p. 135. Boerhaave, Ele* menta Chemise, torn. 2. proc. 114. f Hoffman, torn. 2. p. 369. Gaubius, Patholog. ^ 290. &c. X Van Swieten, Commentar. ^ 82. 99. 423. &c. ^ Nat. Hist, of the Blood, Works, vol.iv. p. 167. fol. ed. 1744. SI Philos. Trans, No. 361. Jones's Abridgment, vol. v. 38 PATHOLOGY OF THE fixed and volatile, by which it is preserved from coagulation. Neutral salts, such as sal Glau- beri, common salt, &c. render it in like manner more fluid, and retard its coagulation; whilst alum coagulates it immediately. It is likewise coagulated or rendered more thick by the vi- triols of zinc, iron, and copper, by concentrated spirit of wine, by the mineral acids, and by most of their combinations wiih earthy and metallic bodies.* But the vegetable acids in general produce no coagulation.f Acetum, according to Boer- haaveJ and Schwknke,$ rather dissolves or attenuates the blood, and hence it is recom- mended as a deobstruent by the former. * Vide Haller, Elem. Physiol, torn. 2. ; Johnson, Animal Chemistry, vol. i. ; Hewson, Experimental Inquiries ; Huxham, on Fevers ; Chaptal, Chemistry, part v. ; Boyle, Natural History of the Blood ; Boerhaave, Elem. Chem. torn. 2. proc 127. f Haller, in loc. cit. % Elem. Chem. torn. 2. proc. 50. <} Hsematologia, vel Sanguinis Historia, HUMAN FLUIDS. 39 It would be unnecessary longer to dwell upon the effects of reagents upon the blood ; for we must not conclude that their effects upon this fluid, whilst in the body, and under the control of the vital principle, or the action of the heart and vessels, would, in all instances, be the same as out of it. Beside, most substances which are thrown into the stomach, are so changed by the action of this viscus, as to have altogether lost their original qualities before they can gain ad- mission into the circulation. Others, again, are less altered thereby ; and some appear to pass into the circulation without any change of property, where they manifest their qualities, and produce effects upon the circulating fluids, not dissimilar to what they would when out of the body. Of this latter kind appear to be many alkaline and saline materials, which are altogether indigestible. Sea-salt, accumulated in the habit in a certain quantity, has long been considered one immediate cause of scurvy;* and, indeed, the records of medicine are not * Vide Culien, First Lines ; — also Lind on the Scurvy- 40 PATHOLOGY OF THE wanting in facts to show that the texture of the blood may be destroyed, and the whole mass brought into a dissolved and putrescent state, by the abuse of this material.* Similar effects have followed the long and abusive use of the lixivial or alkaline salts.f Human blood is easily putrescent, and that most readily in a temperature between 100 and 110 of Fahrenheit :t which includes the general range of febrile heat. Putrefaction is a means of entirely destroying the texture and cohesion of the blood, and resolving this mild and plastic fluid into a thin, acrid, and fetid sanies.^ It soon contracts a disagreeable fetor, which increases so rapidly as to become, in a few days, nearly insupportable ; the crassamentum, in the mean time, loses its firmness, and begins to change the serum to a darkish red colour, and it finally * Percival, Essays, Medical and Experimental, vol. ii. p. 118. f Haller, torn. 2. p. 90. Huxhasi, on Fevers, p. 48, 49. SOS. i Alexander, Experimental Inquiry, chap. ii. ^ Haller, torn. 2. p. 89. See also Browne Langrish, Modern Theory and Practice of Physic, p. S5&. HUMAN FLUIDS. 41 becomes so dissolved as to leave only a very few threads or feces behind ; and in this state it has a strong smell of volatile alkali, and effervesces with acids.* Putrid blood cannot by any art be inspissated, or made to coagulate.f To what extent the putrefaction of this fluid may pro- ceed in the living body, may perhaps be difficult to determine ; but there is evidently a tendency or an approximation to this state, in mail}' malignant disorders where the cohesion of the blood is dissolved, and it is rendered incapable of coagulation.^ So far with regard to the general appearances and properties of blood considered as a whole; but physiologists, to enable them the better to understand the nature of this fluid, and to ascer- tain the various ingredients which enter into its composition, have had recourse to the aid of chemistry; though it must be acknowledged. * Vide Pringle, Diseases of the Army, Append. ; John- son, Animal Chem. vol. i. p. 26. ; Haller, First Lines, ^ 139. ; Boerhaave, Elem. Chem. torn. ii. &c. f Halle r, loc. cit. | Huxham, on the Dissolved and Putrid State of the Blood. 42 PATHOLOGY OP THE that chemical analysis exhibits not the true prin- ciples of the blood, nor even such as are pro- duced in a state of perfect simplicity ; however, it is of some importance in enabling us to speak more intelligibly concerning various changes and combinations that take place in the ani- mal fluids. Blood is by the force of fire resoluble into four species or kinds of matter; namely, aque- ous, terrene, saline, and oily or inflammable.* But fire acts upon this fluid with a strange diversity, according to the degree in which it is applied: below 100 down to 50 it attenuates and putrefies it. From 100 up to 276 it inspis- sates it; and above this degree again, it atte- nuates it, and renders it volatile, sharp, and alkaline, f By a more detailed and elaborate process, human blood is found to contain the following ingredients ; viz. water, fibrin, albumen, gelatin^ * Vide Botle, Nat. Hist, of the Human Blood, vol. iv. ; Haller, First Lines, chap. 5. \ Boerhaaye, Elena. Chem. torn. ii. prec. 119. HUMAN FLUIDS. 43. hydro-sulphuret of ammonia, soda, sub-phos- phate of iron, muriate of soda, phosphate of soda, phosphate of lime ; besides a small portion of benzoic acid, which has been detected by Proust.* Hales found that blood likewise con- tained an aerial Jluid.f The blood, by this analysis, is shown to be a very heterogeneous aggregate, and to contain various fluids or substances, some more ponder- ous and tenacious than others, some aqueous, some alkaline, others oily or inflammable ; but most of them impart to the sanguineous mass a putrid or alkalescent tendency. So long, how- ever, as these several ingredients duly allay or neutralize each other, they are altogether inof- fensive to the body. But if, in consequence of putrefaction, of too violent a degree of heat and motion, or other causes, the crasis of the blood be destroyed, or its texture so opened as to dis- solve the bond of union among the insensible particles, the different salts and oils of the blood * Thomson, System of Chemistry, vol. y. p. 602, t Hales, Statical Essays, 44 PATHOLOGY OP THE are then allowed to recede from their natural combinations, and to run into others, which, being opposite to the mild and emollient nature of healthy blood, still farther dissolve the crasis of this fluid, and increase the disturbance of the motions of the living solids. For the blood in its natural state is bland, although in some dis- eases it is rendered highly acrimonious, and almost putrid; as, for example, in scurvy, where it corrodes its containing vessels, and runs off in profuse hemorrhages from different parts of the body : such, too, is the malignity or corrosive- ness of the humours in this complaint, as in some instances to have forced open the scars of wounds, which had been many years healed; the calli of fractured bones, which had been completely formed for a long while, have been entirely dissolved; the cartilages of the sternum separated from their junction with the ribs; and the epiphyses from the body of the bones.* * Vide Lord Anson's Voyage Round the World, by the Rev. Mr. Walter ; Lind, on Scurvy ; Rouppe^ De Morbis Navigantium ; Mead, Discourse on the Scurvy ; Account of Poupart's Dissections, in Philos. Trans, Abridg. vol. v. HUMAN FLUIDS. 45 We are next to take a brief view of the nature and properties of the proximate compo- nent parts of the blood, as they usually appear from spontaneous separation or decomposition. Blood, as it flows from the vessels of a healthy person, appears to be an homogeneous fluid, of a uniform red colour and consistence ; but left to itself it soon loses its fluidity, and separates into different parts. In the first place it emits spontaneously a subtle aqueous vapour, or halitus, of a smell something urinous, fatuous, or peculiarly animal.* Water impregnated with this vapour in a short time contracts a putrid odour ;f whence it would appear to be a part of the blood highly annualized or loaded with septic particles. In health it is mild and bland, but acquires an acrimony from disease.J As this aroma escapes, the blood which remains, * Dumas, Principes de Physiologie, torn. ii. p. 33. f Johnson, Animal Chem. vol. i. p. 56. J Vapor, ex sanguine exhalans, est mitis, blandus, neque nares, jieque oculos afficiens, in statu tamen prsternaturali plane eodem modo, ut sudor morbificus et vapor ex ulcere manans atque evaporans, acer nares atque oculos ferit. Schwenke, Hcemato- log. p. 90. 46 PATHOLOGY OF THE in the mean time, settles into a tremulous coagu- lated mass,* which is of different degrees of firmness in different subjects.f In a few hours more or less, according to different circum- stances, this coagulated mass, if kept in a tem- perature between 32 and 96 of Fahrenheit, % separates into two distinct parts ; the one a light greenish yellow, or almost colourless fluid, called serum or lymph, in the midst of which floats the other, a red solid body, denominated crassamen- tum, coagulum, or clot. The cause of this spon- taneous decomposition of the blood, when out of the vessels, has not hitherto been ascertained. According to the experiments of Hewson,§ Hunter,|| and others,H it is not essentially con- nected with the influence either of air, heat, cold, or even of motion or rest. The coagu- lation takes place equally in the open air, in vacuo, and in close vessels, whether the blood * Gaubius, Patholog. ^ 336. f Macbride, Theory and Practice of Physic, p. 7, X ScHWENKE, IOC. tit. ^ Experimental Inquiries. j| Treatise on the Blood, Inflam. &c. ? Vide Johnson, Animal Chem. vol. i. HUMAN FLUIDS. 47 be suffered to cool, or be constantly preserved at the temperature at which it is when it issues from the body ; nor is it prevented by agitation, by repose, or by dilution with water. The proportion between the serum and cras- samentum of the blood, appears to vary much in different persons, and even in the same person in different circumstances. In health, the most common proportion, according to the experi- ments and observations of Mr. Boyle,* is equal quantities of each. Browne Languish! esti- mates the crassamentum at rather more than one half of the whole mass of blood. But these proportions are by no means constant ; in many- cases the crassamentum much exceeds, and at other times falls greatly short, of the quantity of serum. From a comparison of the observa- tions and conclusions of most of those who have written with accuracy upon this subject, the limits of the ratios of these two substances to each other appear to be 1 : 1 and 1 : 4 or 5.$ * Nat. Hist, of the Blood, vol. iv. p. 172. 200. f Modern Theory and Practice, p. 73, 74. t Haller, Elem. Physiol, torn. ii. p. 47. 48 PATHOLOGY OP THE Owing to this great diversity in the proportion of these two component parts of the blood to each other, the gravity, consistence, and other sensible qualities of this fluid, and of conse- quence the impressions which it is capable of making upon the general system, and its influ- ence upon the motions of the living solids, must be extremely various. The serum, when separated from the crassa- mentum, is apparently homogeneous, spontane- ously fluid, easily soluble in any quantity of cold water, 1 * and has the smell, taste, and feel of the blood, but its consistence is not so great, f Its specific gravity, according to Jdrin, is 10304 It is the lightest^ part of the blood, possessing less gravity than either the coagulable lymph, or red globules, which together compose the crassamentum. When chemically examined, the serum is dis- covered to be a compound fluid, consisting of a * Gaubius, Patholog. ^ 338. f Thomson, System of Chem. vol. v. p. 597. % Philos. Trans. No. 361. ^ Hunter, Treatise on the Blood, &c. HUMAN FLUIDS. 40 mucilaginous substance dissolved in a water thai holds in solution a small portion of neutral salts. It contains albumen, gelatin, hydro-sul- phuret of ammonia, soda, muriate of soda, phosphate of soda, and phosphate of lime.* In its recent and healthy state, this fluid is perfectly bland, and gives no evidence of a free or disengaged alkali; but it is rendered thin and acrid by putrefaction, and also acquires an alkalescency, as is manifest from its effervescing with acids.f Serum easily putrefies, but not so readily as the crassamentum,J and when once rendered putrid, it cannot, by any art, be inspis- sated $ although in the recent state it is easily coagulable by acids, by oxides, and by alcohol.jj As Harvey first discovered,^ it also coagulates * Thomson, System of Chem. vol. v. p. 598. f Boerhaave, Elem. Chem. torn. ii. proc. 114, 115. % Pringle, Diseases of the Army, Append. ^ Haller, Elem. Physiol, torn. ii. p. 182. || Dumas, Principes de Physiologie, torn. ii. p. 37. If De Generat Anim. 7 50 PATHOLOGY OF THE by heat ; but the temperature required for this purpose has, by different writers, been variously estimated at 148,* 150,f 156,J and 160,$ of Fah- renheit. By this coagulation, the serum is con- verted into a whitish scissile insoluble mass, not unlike the boiled white of an egg, and is also separable into two parts :|| the one a fixed, solid, and somewhat tenacious substance, possessing all the properties of coagulated albumen ;T[ the other, which is not coagulable by these means, a thin, aqueous, and almost colourless fluid, has been termed the serosity, and consists principally of gelatin.** The albumen, or mucilaginous part of the serum, after being coagulated by heat, is inca- pable of solution in the serosity, except by putrefaction, or by the addition of some chemical agent, and then it loses its original property of coagulability by heat.ff But if exposed * ScHWENKE. f GaUSIUS. % CuELEN. ^ HeWSON, || Gaubius, Patholog. ^ 338. 11 Thomson, System of Chem. vol. v. ** Johnson, Animal Chem. vol. i. ft Hews on, Experimental Inquiries, p. 136. HUMAN FLUIDS. 51 to a temperature less than that required for its coagulation, the serum will be gradually inspissated, and at length converted into a solid mass, which can be easily dissolved in water; by the addition of a due proportion of which, it may again be converted into serum, which appears to possess the same properties that it did before, particularly in being coagula- ble by heat.* The increased density or specific gravity of this fluid, which is said to take place in fever,f is to be attributed to a similar inspis- sation, the consequence of great heat or febrile excitement, which greatly dissipates the aque- ous and more fluxile parts of the serum ; whilst the more gross, viscid, and ponderous, that are unable to pass the constricted pores, being alone retained in the circulation, run into a closer cohesion, which necessarily augments the lentor and consistence of the whole mass of serum, and renders it less fit for diluting the other parts of the blood. Hence the necessity of * Hewson, Experimental Inquiries, p. 137. f Bryajs Robinson, Hauler's Elem. Physiol, torn. ii. p. 123. 52 FATH0L0OY OF THE plentiful dilution in all ardent continual fevers, in which the serous part of the blood, as Browne Langrish has demonstrated from a great num- ber of experiments, is always much reduced below the proportion which it ought to bear to the crassamentum.* The crassamentum, or cruor, as it is sometimes called from retaining the red colour which distin- guishes the blood, is spontaneously solid, and possesses considerable density and consistence. Its specific gravity, according to Jurin, amounts to about 1128.f This substance, it is well known, consists of two distinct parts, namely, red particles and coagulable lymph, which ap- pear to be partially separated by a spontaneous action, but may be entirely so, by washing the crassamentum in water. The coagulable lymph, or as it is by some called the gluten, and by others, with more propriety, termed the Jlbrous matter of the blood, is a sub- stance spontaneously solid, having the greatest * Modern Theory and Practice. f Philos. Trans. No. S61. HUMAN FLUIDS. 53 tendency to become concrete of all the circu- lating fluids; and when once coagulated, it is insoluble in water and alcohol, but is readily dissolved by the acids, and even by vinegar.* It is this fibrous matter which imparts to the sanguineous mass its plastic lentor and tenacity, gives solidity and firmness to the crassamentum, and is the true cause of the spontaneous coagu- lation of the blood ; for when deprived of this matter, it is incapable of concretion, a circum- stance not unknown to the ancients.f The specific gravity of the coagulable lymph is greater than that of the serum, but less than that of the red globules. J It putrefies with considerable facility $ and possesses all the pro- perties of Jibrin.\\ This fibrous part of the blood, when thoroughly freed from the red globules or colouring matter, is perfectly tasteless, and of a white colour, exhibiting a membranous texture, * Johnson, Animal Chem. vol. 1. f Vide Aristotle, De Hist. Anim. Lib. iii. Cap. 19. % Hunter, Treatise on the Blood, fcc. ^ Pringle, Diseases of the Army, Append. || Thomson, System of Chem, vol. v. p. 599, 54 PATHOLOGY OF THE consisting of extensible and elastic filaments much of the nature and resemblance of muscu- lar fibre,* which has caused a celebrated physi- cian to assert, " caro nihil aliud est quam sanguis concretus."f It is, in reality, more highly animalized than the serum, and, according to modern physiologists, constitutes the elementary principle or substance of the muscles.J It ap- pears to be prepared by the very act of circula- tion to concur in the growth, nourishment, and augmentation of the parts of the human body. Like the red globules, it would seem to be con- nected with strength. Its quantity is increas- ed in inflammatory complaints,^ but is dimi- nished from debility, from dropsies, and also in putrid fevers, in which it appears to participate in the affection so evidently induced on the mus- cular organs.|| Like the serum, it is readily * Richerand, Elements of Physiology ; Gaubius, Pathol. ^340. f Zaccheus, Quest. Med. Legal, p. 239. X Dumas, Principes de Physiologie, torn. ii. p. S6. ^ Browne Langrish, Modern Theory and Practice. t) Richerand, Elements of Physiology, p. 177, 178, &e.. HUMAN FLUIDS. 55 coagulable by heat, which, according to the ob- servations of Hewson,* takes place between one hundred and fourteen and one hundred and twenty and a half of Fahrenheit ; a temperature but a few degrees removed above that of an acute inflammatory fever. In inflammatory diseases, the coagulable lymph is partly separated in the blood, and covers the crassamentum in form of a white or yellowish tough crust, commonly called the huffy coat, or inflammatory size. This remarkable appearance, so frequently met with in acute disorders, ap- pears, among all the products of the blood, to have been one of those which has principally fixed the attention of physicians. Various opi- nions have prevailed with respect to its nature, origin, and composition. But the perfect ana- logy which it bears to the fibrous matter can leave no doubt as to its nature. Formerly, when inflammations were supposed to take their rise from lentor and obstruction, the buffy coat was deemed a certain proof that the * Experimental Inquiries, p. 82. 56 PATHOLOGY OF THE blood was in a state of too great viscidity, which both rendered its circulation through the vessels proportionably more difficult, and increased its disposition to coagulability. But an ingenious modern physiologist* accounts for the formation of the buff on principles diametrically opposite, alleging that notwithstanding the apparent visci- dity of the blood, after it is drawn and suffered to cool, yet while circulating through the vessels, or immediately on escaping from the body, it is in reality more fluid than in the ordinary state pre- vious to a true inflammation, the action of which consists in an increased fluidity and a lessened coagulability of the sanguineous mass, and parti- cularly of the coagulable lymph; for "when the arteries are acting strongly, whether the whole habit be strong or not, the coagulable lymph is more fluid, and longer in coagulating; of consequence it lets the red particles, which are the heaviest part of the blood, fall down toward the bottom before it coagulates : and upon the spontaneous separation of the crassa- * Hews on, Experimental Inquiries, HUMAN FLUIDS. 57 mentum is divided into two parts; the upper, consisting of the coagulum of the coagulable lymph alone, (which in this case is termed the buff,) the under, consisting partly of this, and partly of the red globules.* According, how- ever, to the observations of De Haenj and others, the phlogistic crust is not always present in a true inflammation, and it exists sometimes where there is not the smallest sign of inflammatory action. ShebbeareJ remarks that he has often observed this siziness attend the blood of persons in full health and vigour, where not the least symptom of disease had taken place, or was consequent of this appearance. This morbid aspect of the blood, then, is not of that formi- dable nature, or of that destructive consequence to health, which many have apprehended; neither is it a certain sign of inflammation, much less can its occurrence alone, on all occasions, indi- cate or determine the repeated use of the lancet ; * Fordyce, Elements of the Practice of Physic, f Ratio Medendi, p. 36, 37, Sic. $ Practice of Physic, vol. ii. p. 39. 8 5g FATHOLOGY OF THE for not to mention pregnancy, in which the ap- pearance is almost constant,* there are other circumstances under which such evacuation would be improper notwithstanding the presence of the buff: nor is it the only call for venesec- tion; there are several morbid conditions of blood indicative of an equal or perhaps higher grade of disease, and of a more vehement call for the use of the lancet. This buff has been observed in the last stage of yellow feveiyf- and De HaenJ lias seen it as late as the twelfth day of a putrid or petechial fever. These facts clearly show that it would be improper to determine from the presence of the size alone, when venesection should be repeated ; and yet have there been not a few who have erroneously inclined to draw such a conclusion. It yet remains to consider the red particles, or sanguineous globules, as they are sometimes called, which are ascertained to be distinct bodies pos- * DeHaen, Ratio Medendi,p. 39. f Hosack, MS. Notes on the Theory and Practice of Phy- sic. % Ratio Medendi, p. 342. HUMAN FLUIDS. 59 sessing form and colour; but such is their extreme tenuity, that it is only through the medium of the microscope that they can be seen and ex- amined ; by the aid of which instrument they were first discovered in the year 1673 by the celebrated Leeuwenhoeck.* The doctrine* taught by the learned Boerhaave, that the blood was a fluid consisting of globules of differ- ent magnitudes, decreasing in regular series* and which he appears to have embraced on the authority of Leeuwenhoeck, who imagined that he observed, with the aid of his glasses, that six serous globules, which, when separate, were of a yellow colour, combined together to form one red globule, is now pretty generally exploded. These globular bodies are highly soluble in pure water, but in the serum of the blood they are wholly insoluble, being merely diffused or suspended in this fluid, and not chemically dis- solved ; and it is by means of this vehicle, too^ that they are rendered movable through the * Halx.ee, Elem. Physiol, torn. ii. p. 51. 60 PATHOLOGY OF THE vessels ; for, of themselves, they appear incapa- ble of constituting a fluxile mass. The colour, which they impart to the blood, varies in inten- sity according to the different state of weakness or strength, of disease or health, and is of a lighter or darker shade as derived from arteries or veins. In health and vigour, the blood is generally of a bright and lively red ; but is more pale in dropsies, and in subjects of weak or enfeebled constitutions ; and, in general, in pro- portion to the depth of its tint will be its densi- ty, consistence, saltness, and odour. 5 * In judging of the state or qualities of the blood, therefore, Celsds very properly recommends an attention to its colour as well as to its other habitudes.f Physiologists have not, perhaps, as yet, clearly ascertained the several uses to which the glo- bules are subservient in the economy ; they ap- * Richerand, Elements of Physiology. f E vena cum sanguis erumpit, colorem ejus habitumque oportet attendere. Nam si is crassus et niger est, vitiosus est ; ideoque utiliter effunditur : si rubet et pellucet, integer est ; eaque niissio sanguinis adeo non prodest, ut etiam noceat, pro- tinusque is supprimendus est. Celsus, lib. iL cap. 10. HUMAN FLUIDS. 61 pear, however, to be connected with strength, and to be necessary to the due excitement of the heart and arteries. We have already shown,* that the blood is the natural stimulus, the pre- sence of which determines the contractions of the heart ; and though it may be supposed that all the parts of the blood contribute to this end, yet doth it appear probable that this property is more especially inherent in the sanguineous globules, which, from being the most dense and ponderous part of the blood, are necessarily more eminently calculated for impressing and receiving the force of the heart, and also for keeping up its vibrations, as well as those of the arteries.f Hence it is easy to understand why the generation of heat should be said to be the principal use of the globular part of the blood ; and that its quantity should be found propor- * See p. £4, 25. f Nempe eadem semper vi cordis posita, momentum san- guinis cum ejus densitate crescit. Creditum est, etiam cor melius a densiori sanguine stimulari, cum procul dubio fibne cordis interna? profundius a ponderosiori sanguine emoveantur, et canis dispereat, quando ab impulsa aqua sanguis nunc valde diluitur. Haller, Ehm. Physiol, torn, i\. p. 149. 62 PATHOLOGY OF THE donate to the natural temperature of the blood.* An exuberance of globules, therefore, by too much increasing the density and gravity of the blood, causes a higher action of all the vital motions, an augmentation of heat, and what is a necessary consequence of these, a phlogistic diathesis of body, or a strong predisposition to inflammatory complaints, or all diseases of in- creased circulation and temperature. It is in blood of this character, too, that the semina of contagious diseases find a more powerful pabu- lum, f Agreeable to the laws of dynamics, the glo- bules in receiving the common impulse from the heart, on account of their greater density, neces- sarily acquire a greater impetus, and are thus rendered efficacious, not only in propelling or setting in motion the inferior order of humours, but moreover by their vibrations and concus- sions they are almost as essential for digesting and farther attenuating the humours as the elas- tic fibres and vessels themselves ; so that when, * Hallek, First Lines, ^ 152. f Vide Walkef. on the Small Pox. HUMAN FLUIDS* 63 in consequence of frequent bleedings, hemor- rhages, or other causes, the blood is too much exhausted of its globules, and degenerates from its red and dense nature into an impoverished or serous state, the requisite digestion of the chyle in the blood will no longer be completed ; the heart and blood vessels, from a want of due stimulation, have their motions impaired, the necessary generation of animal heat is prevent- ed, and all the vital powers suffer a correspond- ing declension.* The stability or permanence and strength of the body, therefore, depend upon a due propor- tion of the sanguineous globules; and health itself, which supposes a proper degree of den- sity and consistence in the circulating fluid, can neither subsist without the thicker parts of the blood, or what is usually called the crassamen- turn, and a diminution of its quantity causes a stagnation in all the smaller vessels, with univer- sal paleness, coldness, and debility : nor can the functions of life and health be maintained with- * Boerhaave, Instit. Med. ; Haller, First Lines, 64 PATHOLOGY OF THE out the serum or fluids of the inferior orders, since the crassamentum, deprived of its aqueous portion, concretes and obstructs the straits of the vessels, impedes the cutaneous perspiration, and produces too great heat and excitement.* We have now given a short and general analysis of the blood. We have seen that the sanguineous mass, or that portion of our fluids, which fills and flows in the red vessels, and is the reservoir or common source from which all the other humours seem to be derived, is, every- where, a heterogeneous aggregate, consisting chiefly and especially of four distinct parts : to wit, albumen, serosity, coagulable lymph, and red globules, in one or the other of which are con- tained all the ingredients naturally belonging to the blood. When separately examined, these several parts are found, in most of their qualities and accidents, to be very distinct; some being more dense, ponderous, and cohesive, or more easily putrescent than others ; some of a nature approaching to solidity, and others more tenuous * Haller, First Lines, ^ 154, HUMAN FLUIDS. 65 and fluxile ; but when intimately intermixed or combined in the form of blood, these several parts mutually temper, or qualify each other, and constitute an entirely new and apparently homogeneous mass, of a uniform density, con- sistence, and fluidity throughout; which qualities of the aggregate, however, must vary with the different proportions of the proximate ingredients which constitute it as a whole. Nor, indeed, would it appear competent to the integrity of the functions, that these parts should be united in any proportions indifferently. The blood, to possess a perfectly healthy texture and consist- ence, adapted to all the purposes for which it is designed, would seem to require a certain mutual proportion; any considerable deviations from which must so affect the powers and qualities of the mass, as to render it less fit for the well being of the economy.* " Nor are the proportions of the elements, which we have hitherto mentioned, * Verosimile est dari certam aliquam trium sanguinis partium proportionem mutuam, quag sanitati perfects maxirae conveniat. Gaubius, Patholog. *j 353. 9 QQ PATHOLOGY OF THE constant : for an active life, manhood, and lever, increase the cruor, redness, coagulability, cohe- sion of the parts, firmness of the coagulated serum, weight, and alkaline principles. The serum, and the mucus it contains, are increased by the contrary causes ; a less mature age, inac- tive life, and a watery and vegetable diet ; by all which, the crassamentum of the blood is les- sened, and its watery part increased. Old age again augments the cruor, and diminishes the gelatinous part."* We have seen, too, that in combination with the insensible particles of the blood, are sul- phureous, oleaginous, and different saline mate- rials both fixed and volatile, which, in a proper quantity, appear essential toward maintaining a natural and healthy eras is ; and so long as they hold their natural combinations, they are devest- ed of all noxious qualities : but when, from any cause, these acrid substances are too copiously evolved, exalted, and rendered volatile, they must necessarily become sharp, acrid, and corro- * Haller, First Lines, q 150, HUMAN FLUIDS. 67 sive, and thereby, more or less, introduce a noxious acrimonious quality, which will be ca- pable of still further vitiating the crasis of the blood, of irritating the solids, and weakening and destroying the vital powers. The occur- rence of a spontaneous and noxious acrimony, however, is not very common, which, indeed, is ascribable to the constant and easy egress from the system, by the urinary passages and pores of the skin ; through which media, the degenerating and degenerated parts of the blood are elimi- nated, or thrown out from the circulation. From all that has been said, then, upon the nature of the blood ; from a due considera- tion of its heterogeneity, the various parts of which it is compounded, and their various qualities or accidents, the diversity of their composition and properties, and the differ- ence of the causes by which they are severally influenced, it is easy to understand that the sen- sible and chemical qualities of this fluid may 5 under different circumstances, be variously af- fected. For though mankind might, in the strict- est sense of the word, be said to be of one blood. 6H PATHOLOGY OF THE yet different climates, seasons, modes of living, air, exercise, indolence, luxury, intemperance, different aliments, want of common necessaries, or the continued use of such as are of a vitiated quality, the intervention of disease, and a variety of other causes, cannot fail, sooner or later, to affect the constitution, or to influence and diver- sify the nature, powers, and sensible qualities of this one animal fluid. Having given a general view of the nature of the blood, of the effects which chemical agents have upon it, of its spontaneous separation into its proximate component parts, and of their various properties, it will be proper, in the next place, to trace the outlines of its vitiations, taking them in the order before mentioned. Morbid Fluidity of the Blood. Fluidity is that property of bodies, by which their parts, being very fine and small, are so dis- posed by motion and figure, as readily to yield HUMAN FLUIDS. 69 to any force impressed, and to be easily moved among one another in all manner of directions. In this respect, fluidity stands opposed to solidity, whose essential character is stability and firm- ness. All fluids differ from solids, but they differ only in the cohesion of matter, which the former in some measure possess, although small in degree ; for cohesion entirely destro} 7 ed takes away the idea of a fluid as well as of a solid ; so, on the contrary, when it is increased, it changes a fluid into a solid. The blood is called a fluid, be- cause, while circulating through the vessels, and under the control of the vital principle, it is always found in a fluxile state ; a property essential to its offices or functions; for, without this form, it would be incapable of a circulatory motion, or of being propelled through the flexile tubes, distributed to all parts of the living engine, and again returned to the heart. It could not be divided into different portions, as the vessels branch off, nor could it pass through the straits of the vessels, and admit of the various separa- tion of its parts that are intended for the aug- mentation and repair of the whole body; nei- 70 PATHOLOGY OF THE ther could it be adapted for furnishing the differ- ent secretions and excretions. The most simple affection of the blood, there- fore, is that which has for its foundation a change in the state of the natural cohesion, or fluidity. A knowledge of the conditions upon which the fluidity of the blood depends, will point out the nature of its vitiations. The force of cohesion, when natural, is not the same among all the parts of the blood ; each has its own degree by which it is fitted for the uses required ; and this cohesion being increased or diminished, fluidity will be proportionably so. The blood, when examined by the senses, as we have before shown, is found to be composed of different matters, in part fluid, another part being solid. The crassamentum, which by itself is spontaneously solid, owes its fluidity to an interfluent vehicle, by which its parts are dilu- ted, separated, and adapted for a circulatory motion through the vessels. The varied propor- tion of the one to the other of these parts, therefore, will constitute different degrees of fluidity in the mass of blood 5 and vary the con- HUMAN FLUIDS. 71 sistence. Nor is the proportion between the quantities of serum and crassamentum so fixed as might, perhaps, be apprehended. Haller observes, " In massa sanguinea media pars, et ultra, cruoris est : in robore valido serum min- uitur ad tertiam partem ; in febre ad quartam et quintam reducitur ; in morbis a debilitate incre- scit."^ The gravity, consistence, and fluidity of the blood, therefore, will be equally various. A redundancy of serum, which also increases the proportion of water in the blood, by too much diluting and attenuating the crassamentum, is productive of an aqueous tenuity of the whole mass of circulating fluids, and of the diseases occasioned by serous congestions, or by a want of due motion and heat. An exuberance of crassamentum, on the con- trary, or in other words, a paucity of serum, by admitting a nearer approximation, and more close and obstinate attraction between the gross and viscid parts of the blood, so as to favour their union into larger and more dense particles^ * Primse Linese Physiologic, ^ 138. 72 PATHOLOGY OF THE is productive of a preternatural spissitude and viscidity of the whole sanguineous mass, or at least of such a glutinous adhesiveness of its parts, as impedes or prevents its free and equa- ble circulation through the different orders of vessels. The fluidity of the blood, then, may be faulty, or preternaturally affected in two ways, either by an excess or defect of fluidity ; the former vitiation is denominated tenuity and resolution; the latter spissitude and viscidity. Tenuity of the humours, which indicates an excess of fluidity, is of different kinds. The first and most simple species may be called the aqueous, which is caused by a redundance of serum, or water, in the humours, by which inter- fluent medium, the other constituent parts of the blood are too much separated, and the globular part being diffused into too small particles, too loosely cohering, are attenuated, and the whole mass of humours becomes preternaturally thin and fluxile.* * Gaubius, Patholog. ^ 237. HUMAN FLUIDS. 73 This state of the humours arises from the ex- ternal and internal abuse of watery things ; a scanty, or a little nutritious diet; depraved concoction in the stomach, lungs, and other viscera; torpor and debility of the heart and blood vessels ; a sedentary, inactive life, espe- cially in a moist atmosphere; suppression of the usual watery excrements by the pores of the skin, and by the urinary passages, either from cold, or from some vice in the organs them- selves ; too copious and frequent evacuations of blood, which unbends the force of the heart and vessels, produces a languid circulation, diminu- tion of vital heat, and a consequent retention of the usual watery excretions.* The consequences of this thin and impove* rished state of the blood, are want of due ex- citement in the heart and arteries ; torpor of all the functions; defective heat and nourishment; and the solids themselves, by being, as it were* perpetually macerated in watery humours, lose * Vide Gregort, Conspectus Medicinse, ^ 520. ; Gaubius, loc. cit. 10 74 PATHOLOGY OP THE iheir natural elasticity, and become weak and flaccid ; whence a languid circulation, coldness, universal paleness, debility, cachexy, serous congestions, hydropical effusions, Src. Some physicians have maintained, that our fluids could not possibly offend by too great a tenuity ; since thin juices pass with least impe- diment through the capillary vessels ; whence, it was supposed, " that this condition of the hu- mours must be productive of the openest and readiest circulation of them." Such person* do not appear to have rightly considered the healthy nature of our fluids ; for the blood of a strong and healthy subject, as we have before remarked, is a fluid of considerable density and thickness, by which, when withdrawn from the vessels, it is disposed immediately to run into a solid cohesive mass; whereas, the blood, in weak and valetudinary subjects, has not such firmness of texture ; but is much thinner, and less easily disposed to a solid cohesion. From a consideration of this one single fact, they might have easily perceived, that the occurrence of a too thin state of the humours would render a HUMAN 1'LUIDS. 75 strong and healthy person in the condition of one who is weak and valetudinary. Moreover, since the red part of the blood, (which by the largeness of its globules is confined within the larger arteries and veins, and hinders them from collapsing,) in receiving the common impulse from the heart, by reason of the greater density of its parts, necessarily acquires a greater im- petus or motion, which it communicates to the other humours, and assists in propelling them through the inferior order of vessels ; and as the heart itself is more duly excited by the ponder- ous globules ; therefore, when the blood becomes too thin and watery, or is deprived of its due proportion of globules, the action of the heart and arteries is impaired, the motion of the blood weakened, and the heat of the body proportion- ably lessened. Whence the watery liquors will not be easily exhaled from the body, but remain therein, and distend the vessels so as to give rise to serous congestions, or to be effused into the different cavities of the body, and thus pro- duce a cachexy or dropsy. It is evident, there- fore, that the animal humours may offend by a 76 PATHOLOGY OF THE too watery state, or by becoming preternaturally tenuous.* The other species of morbid tenuity, which is indicative of a dissolved state of the blood, arises from want of a due pressure of the hu- mours by the vital and elastic force of the vessels and viscera ; or it is of a compound nature, having an acrimony joined with the humours, by the attenuating power of which the globules and coagulable lymph are dissolved and broken down, and the crasis of the whole mass of blood so much injured as to prevent the mutual and necessary coherence of its parts.f Hewson has demonstrated, by some ingenious experiments, that the coagulable lymph of the blood may be so much attenuated as to dilute even the serum itself.J This dissolution of the animal fluids takes place from an acrimony varying greatly in its nature, either from the native oils and salts, resident in the body, being too much in quantity, or too largely evolved * Vide Van Swieten, Commentar. ^ 1174, &tc. f Vide Gaubius, Patholog. ^ 288. ; Van Swieten, he. cit. i Experimental Inquiries, Exp. xviii. p. 49. HUMAN FLUIDS. 77 or corrupted ; or from some extraneous accession from meat, drink, medicines, poisons, miasmata, contagions.* A resolution of the red particles, and an at- tenuation of the coagulable lymph, says a late celebrated physician, are effects which fre- quently occur in the system, though in different degrees. It is a temperament natural to some families ; and, when it is hereditary, may be greatly increased by external causes ; and even these causes of themselves are sufficient to induce the habit: such as a course of close, sultry weather ; a continued application of warm humid air to the body; animal steams, where many persons are crowded together in small ill- ventilated apartments; putrid exhalations; the air of an hospital, where putrid ulcers, dysente- ries, &c. prevail.f This dissolved state of the blood is equiva- lent to what is denominated, by many eminent authors, the putrid diathesis; and forms a habit * Gaubius, loc. tit. f Walker, An Inquiry into the Small Pox, p. 120, 121. 78 PATHOLOGY OF THE of body extremely obnoxious to low, nervous, putrid fevers, and to the operation of contagious virus. The general indications of this morbid tem- perament are, paleness of complexion, soft and relaxed fibres, aversion to motion, fatigue from the smallest exertions : persons of this constitu- tion, too, are, on many occasions, liable to faint.* Another vitiation of fluidity, to wit, a preter- natural spissitude, or too great a viscidity, or thickness in the consistence of the blood, is a constitution or crasis directly opposite to tenuity, and supposes a deficiency of fluidity, which is no less various, and must be explained in order, according to its differences. If the thickness, or cohesion of the humours, arises from an excess of animal motion, or from a too violent circula- tion and great strength of vessels, it is then called an inflammatory spissitude, or more pro- perly a phlogistic disposition of the humours : but when, from a defect of the animal motions, or from too languid a circulation, and weakness Walker, An Inquiry into the Small Pox, p. 122. HUMAN FLUIDS. 79 of the vessels and viscera ; from a loss of the fluids ; or from feeding too plentifully upon such substances and kinds of aliments, as are of a glutinous and tenacious quality, or in themselves apt to run into such cohesions as cannot be easily separated by the vital powers, it has been then denominated a glutinous or viscid lentor ; which is productive of that white swelling, or turgescence of body, that the ancient physicians have called the leucophlegmacy, (^uKop^^aT/*,) or white phlegm.* In the latter vitiation, the blood is so far de^e- nerated as to lose both its natural redness and density, to grow lighter, become more lax, and acquire almost a mucous nature. In this state of the blood, the coagulable lymph is not suffi- ciently participant of an animal nature ; the red globules are too few in number, and those too loosely compacted; and the serum is more viscid or ropy than ordinary. In a word, the whole sanguineous mass becomes too gross, * Vide Van Swietejv, Commentar. ^ 69 to 76. fy 1174, gO PATHOLOGY OF THE viscous, and inactive : and when, in this morbid state, the circulating fluid has been imprudently withdrawn from the vessels, a very little red con- crete blood is found swimming in a large quan- tity of viscid glutinous serum.* The phlogistic constitution of the blood, on the contrary, indicates a deficiency of serum, or rather a superabundance of crassamentum, which necessarily increases the density, firmness, and consistency of the whole mass of blood. The red globules are in too great quantity, and too closely compacted or condensed ; the coagulable lymph is more highly animalized, and the serum more dense than ordinary ; and thus the whole mass of blood, being rendered too dense and ponderous, is, in virtue thereof, proportionably more exciting to the heart and arteries, and, of consequence, is productive of a too active and vigorous circulation. This morbid quality is, sometimes, very evident to the senses, where the blood that is taken from some persons has very * Van Swieten, Commentar. ^ 72. HUMAN FLUIDS. 81 little serum separated from the coagulum, though it has stood a sufficient time for such separation : thus it commonly is in acute inflammatory or ardent fevers, and likewise in the beginning of some eruptive fevers.* It also appears, from the experiments of Browne Languish,! that the blood is more thick, dense, and tenacious, or at least that the crassamentum abounds more, and the serum less in quotidians than in tertians, and in tertians than in quartans ; and in all these the red globules bear a greater proportion than is consistent with health ; but in quotidians, ceteris paribus, the blood comes nearest to an inflam- matory state. Now, when the sanguineous glo- bules are in great number and very dense, and the vessels themselves strong and elastic, a greater momentum of motion must be produced in the circulating fluids, and, of consequence, much heat, which both dissipates the more subtle and watery parts of the blood, and incrassates * Vide Lobb, Practice of Physic, vol. i. lect. 3. ; Browne Languish, Modern Theory and Practice, f Ut antea, chap. v. 11 82 PATHOLOGY OF THE the remainder, so that it becomes more firm and cohesive, and less fit to circulate through the minima vascula, or extreme capillary vessels. The red particles and coagulable lymph have been justly considered, by physiologists, as the most active or inflammatory parts of the blood ; and this quality they appear to derive princi- pally from their greater density or weight, by which the action of the heart and arteries is more duly excited ; and of consequence there is produced a greater impetus of the circulating fluids, with a proportionate augmentation of temperature ; for whatever be the cause of the natural or vital heat, nothing is more plain, than that its increase and decrease are always, ceteris paribus, as the different velocities or projectile force of the blood. We may observe, that all persons readily have their temperature increased by labour, or exercise, which augments the mo- tions of the blood; but persons in health, who have a due quantity of red particles in their blood, are sooner heated by exercise, than those who are infirm, and have a poor blood, or few sanguineous globules. And, indeed, in proper- HUMAN FLUIDS. 83 tion to the crassamentum in the blood, is the de- gree of heat in all animals. The experiments of Shebbeare demonstrate, that all animals, whose degree of heat is superior to the human, have a larger proportion of crassamentum in their blood, than mankind in health.* Is it not pro- bable, therefore, that different proportions of red globules in the blood of persons in health may have some share in producing a difference of temperament ? The signs of an inflammatory diathesis of the blood, are great strength of the fibres, a strong, firm pulse, much heat, and redness that is parti- cularly observable in those places where the tender vessels are not covered with true skin ; as in the lips, the gums, the tongue, the inside of the mouth, the nares, the corners of the eyes, the adnata, the inside of the eyelids, fyc. But when the glutinous or viscid lentor predominates in the humours, there is paleness in all these parts; a weak and languid circulation, w 7 ith coldness, sluggishness, and a laxity or doughy • * Shebeearf, Practice of Physic, vol. i. p. 248. 84 PATHOLOGY OF THE softness and intumescence of the whole body. Hence, in the beginning of a leucophlegtnatic habit, persons, observing themselves grow more full and bloated, are deceived by this specious appearance, and are often pleased to think they are perfectly well, and growing fat. In general, persons of vigorous, robust con- stitutions, of strong, rigid fibres, who take much exercise, and a full diet, are peculiarly subject to a rich, dense, inflammatory blood, which ne- cessarily increases the phlogistic diathesis of body, and renders it constantly liable to acute ardent fevers, and inflammations ; on the acces- sion of which there will be produced the most violent symptoms, which will quickly prove fatal except when prevented by timely bleeding, cool- ing, diluting, emollient drinks and medicines. The other condition of the circulating fluid, on the contrary, is common to persons of a relaxed habit of body, or those in whom the solids have lost their due force and elasticity ; for whenever this happens, the parts of the blood, being less agitated, cannot but thereby the more at- tract one another, and in this case cohere in too HUMAN FLUIDS. 85 viscous a manner; nor can the action of the ves- sels divide the juices so minutely as is required for their circulating through the very small pas- sages of the minima vascula or capillary vessels. From the viscid or slimy lentor, therefore, ob- structing the small vessels, and preventing the due motion of the humours through them, there necessarily follows an imperfect or disordered state of all the concoctions, circulations, secre- tions, excretions, and all the vital, natural, and animal motions,* Hence, universal indigestion, weakness, coldness, paleness, cacoehymy, leuco- phlegmatic and dropsical disorders, glandular obstructions, and fevers of the low and slow nervous kind. In this state, too, the blood having lost its most vital principles, and at the same time being too slowly moved, at length, for want of due motion and circulation, falls into a spon- taneous corruption, productive, at last, of such a degree of acrimony or putrescency, as not only to corrode and destroy the contexture of the Boerhaave, Aphor. de cognosc. et curand. Morbis, 72, 86 PATHOLOGY OF THE more delicate solids, but sometimes to end in fevers of a dangerous, putrid, malignant na- ture.* It will appear from what has already been said, that these two different states of the fluids may not improperly, to a certain degree, be con- sidered as constitutional, for they naturally fol- low the respective state of the solids ; so that a strong, rich, inflammatory blood always attends a strong, elastic set of vessels ; and a gross, viscous, or weak blood, a relaxed habit of body, or a weak state of the vessels and viscera ; but where either considerably deviates from the standard of nature, it becomes a real vitiation, and, as such, is to be duly regarded in the treatment of any concurring disease. As the several states or conditions of blood, which have now been described, may arise from various causes, and be also complicated with dif- ferent habits of body, it is obvious that, as it re- spects their curative indication, nothing in gene- ral can be here determined ; but we must care- * Vide Huxham, Essay on Fevers. HUMAN FLUIDS. 87 fully endeavour to ascertain the nature of the morbid quality in the humours, and also the cause from which it proceeds, a right apprehen- sion of which frequently leads to the proper correction.* For example, if the humours are too thin and aqueous, from an abuse of watery things, the cure will be effected by a dry regi- men and diet, and by giving strength to the over- relaxed vessels; but if they are dissolved by acrimony, or some contagious miasmata, the indication is to correct and weaken the same by plenty of watery and emollient drinks. Again, where there is an inflammatory disposition of the blood, the vessels are to be relaxed, that they may the less compress their contained humours; but when a viscid lentor and thickness prevail, the strength of the vessels is to be increased, that they may the more duly actuate the con- tained humours, and work them up to a healthy texture and consistence.! * Et causae quoque estimatio sa^pe morbum solvit. Ceisus* In Prmfat, lib. i. p. 16. i Van Swietei*, Commentar. ^ 1174. §3 PATHOLOGY OF THE Physicians have described another vitiation of fluidity, in which the blood is supposed to lose its natural mildness and fluxility, and to grow preternaturally thick, black, and viscid ; so as to be less fit for its different motions, and the uses of life. It consists, therefore, in both a morbid spissitude and viscidity. Now the ancients, as may be learned in Aret^us,^ actually observed such a degeneration of the blood in melancholic persons; which is, likewise, confirmed by the observations of modern physicians.f The causes of this morbid quality of the blood and humours, may be every thing that expels the watery and more moveable parts of our juices, and has a tendency to fix the rest : of conse- quence, it has for its matter the thick oil and earth, or the more gross and more tenacious parts of the blood united and compacted together.^ Now if the entire mass of blood be in any way exhausted of its succulent, and more moveable * De Curat Morb. Diutura. lib. i. cap. 5. f Vide Hoffman, Medicin. Rational. System, torn. iv. p. 201 ; Mead, Medical Works, p. 372. 424. X Boerhaave, Aphor. 1093. 1095. HUMAN FLUIDS. 89 parts, it necessarily follows, that the thick and less fluxile will then be left in closer cohesion ; whereupon, the common circulating mass, despoiled of its limpid vehicle, assumes a more tenacious and immovable disposition, by which its circulation through the smaller vessels will be rendered more difficult ; while, at the same time, the said blood itself will be less mild than natu- ral, or, at least, more apt to degenerate into an acrid state, in consequence of any given quan- tity thereof containing proportionably a greater stock of animal salts and oils. The refinement of modern investigators has added to the consideration of the animal fluids a new source of disease, supposed to be connect- ed with those changes which depend on the composition of our fluids ; that is, their relation with different proportions of oxygen, nitrogen, carbon, and hydrogen. But as this subject has not yet received, from the pathologist, a share of public attention, it may, in this place, be passed over without any further notice. This finishes morbid fluidity, or the considera- tion of those simple affections of the blood de- 12 90 PATHOLOGY OF THE pending upon some change or difference in the state of its natural cohesion and consistence: which change, it has been shown, may arise either from some variation in the proportion of the discordant parts of which the blood consists, or from some default in the texture of this fluid. Now, as the state of the fluids, in the body, appears in general to depend chiefly and espe- cially on that of the solids, it will, no doubt, by some, be urged, that to the consideration of the former we have attached more importance than they in reality merit ; it being seldom that we can fairly and immediately deduce morbid symp- toms from the state of the fluids alone. In reply to this, it will suffice to observe, that in describ- ing the various morbid constitutions of the animal fluids, and their effects upon the body, we have represented them such as they may generally be supposed to be in their full extent, and when influ- enced by circumstances favourable to their ope- ration : not that the same effects may not proceed from other causes, or in general be traced with more certainty to other circumstances of the con- HUMAN FLUIDS. 91 stitution more fundamental, and more powerful in determining its condition. It was on a former occasion remarked, that such is the limits of health, that every deviation from the sound state is not disease ; though probably each may be supposed to form a predisposition to disease Thus with the blood itself: every deviation from the natural standard does not necessarily become an immediate cause of disease; but still, each may render the animal body more ob- noxious to the influence of morbific causes in general; and by concurring with the solids themselves, on many occasions produce disor- ders in the constitution, which would not other- wise have taken place. It is certain, ceteris paribus, that a poor, watery blood will produce effects upon the constitution different from those arising from an inflammatory blood, or such as abounds too much in red particles. This latter, on account of its greater density and weight, will more duly excite the heart and arteries, pro- duce a higher degree of the vital heat and mo- tions, and in this manner predispose the body to ardent and inflammatory fevers, or all diseases 92 PATHOLOGY OF THE of increased circulation and heat : whereas, blood of the former character, from containing too small a quantity of red particles, or being less dense and ponderous than natural, will be less exciting to the heart, and of consequence be attended with a lower state of the vital heat and motions. The solids themselves, too, from being perpetually loaded with these watery hu- mours, will lose much of their natural cohesion and elasticity, and become weak and flaccid. To conclude : although the consideration of the state of the solids, or rather the conside- ration of the motions and moving powers of the animal system ought, doubtless, to form the leading inquiry in distinguishing the different states of the body both in health and sickness ; yet it must also be acknowledged, that the state and various condition of the animal fluids have some share in this respect ; and, of consequence, are not to be entirely neglected by the patho- logist. HUMAN FLUIDS. 93 Morbid Acrimonies of the Blood, When we consider the fluids as they are in the human body when sound, says a learned writer,* it is evident, that they are not fitted by fluidity alone for answering the ends required ; but that other properties are requisite, and these are either common to all, or proper to single ones, by which they both differ from other liquors not of the human body, and from one another. The most common characteristic quality of our healthy circulating fluids is the mild or bland ; directly opposite to which, is the vitiation of acrimony, as it is called, which appears to have been much too frequently and too rashly accused as the cause of many diseases. Nature has been solicitously careful to guard against the admis- sion of such a pernicious quality in our humours ; for she has not only taken various precautions to prevent acrid materials from reaching the com- Gaubius, Patholog. ^ 289, S4 PATHOLOGY OF THE mon mass of blood, but further, even after having entered the circulation, they are fre- quently rendered inert by being largely diluted with a considerable portion of the circulating fluids, and probably sheathed by the mucilagin- ous, or albuminous portion of the blood ; or else by stimulating the secretory and excretory or- gans to a larger secretion, they are eliminated, before they have time to hurt, together with the saline, putrescent, and other degenerated and degenerating parts that are continually passing off by the several excretions. There are, however, some evidences of the operation of a morbid acrimony. The subject must there- fore be inquired into. The term acrimony, as applied to the human body, includes all those noxious and morbific matters, which, being mixed with the blood, either destroy its healthy crasis, stimulate the living solids, or corrode the inert.* Pathologists have divided acrids into mechan- ical and chemical, but in this place it will be ne- * Macbride, Theory and Practice of Physic, p. 85. HUMAN FLUIDS. 95 cessary to consider, particularly, the latter only ; since it alone, as Gaubius remarks, may so in- fect the fluids as to constitute a part of them. The sources of a morbid acrimony are either internal, and derived from the spontaneous de- generation of the humours themselves ; or exter- nal, and situated in the perpetual intercourse which the living human body holds with various external things ; and thus the air, meat, drink 9 condiments, medicines, poisons, miasmata, and contagions, may introduce different acrimonies into the fluids in different ways, which being there evolved and corrupted by heat and mo- tion, or excited into action by the vital power* induce itchings, pains, erosions, various kinds of eruptions, with irregularities in the animal motions, spasms, and many other perturbations of the functions. It is one of the laws of acri- mony to act, or become more injurious to the body, in proportion as it is moved. Hence scor- butic persons are rendered most sensible of their pains upon motion or exercise of any kind^ 96 PATHOLOGY OF THE which accords with the well-known axiom, acria nulla aguntj si non movedntur.* The principle sources of acrimony next merit consideration. The various kinds of food or alimentary sub- stances, which have been accused of introducing an acrimony into the prima vice, and afterwards into the fluids, do, no doubt, many of them pro- duce such an effect; but there are also, proba- bly, many others which have little influence in this respect. An acid in the stomach produced from a vegetable diet, or the continued use of acids and acescent things, which cannot be sub- dued by the powers of the body, certainly injures the digestion, and produces, in consequence, debility ; but it perhaps rarely, if ever, enters so largely into the circulation as to taint the mass of blood. There is no trace of an acid in this humour, nor even in the secreted fluids, if we except the ureal and arthritic concretions, and of these, the latter only can be obscurely traced to a vegetable, or acescent aliment. An * De Gqrter, Tract de Perspir.cap.yii. ^ 5. HUMAN FLUIDS. 97 acid, indeed, is foreign to the body ; for no ani- mal humour, properly so called, ever appears to become acid of itself. Should an acid acrimony, therefore, ever actually be discovered to take place in the blood, its origin would seem to be owing to the aliments not being sufficiently changed by the vital powers. An alkalescent diet is not frequent. The aliments derived from the animal kingdom, how- ever, approach much nearer to this character than those from the vegetable. Animal substances are almost all of an alka- lescent, or, perhaps, rather a putrescent nature. They greatly abound in salts and subtle oils. An excess of animal food, therefore, by convey- ing into the system, large quantities of saline and other active particles, is thought to inflame the juices, produce an alkaline disposition of the blood, and strongly incline it to putrefaction.* * A person that lives on nothing but mere water, and flesh or fish, without any thing either acid or acescent, soon contracts a very great rankness in all his humours ; he grows feverish, and at length his blood runs into a state of putrefaction. Httxhatvi, Dissertation on the Ulcerous Sore-Throat, p. 304. 13 1)8 PATHOLOGY OF THE The experiments of Dr. Young show the influ- ence of animal food in giving an alkalescency to the animal fluids, and also the necessity of a due proportion of vegetable aliment, or aces- cents, to correct this tendency in the humours. These experiments inform us, that by feeding a bitch on animal food alone, she " afforded a milk acescent and spontaneously coagulating, like that of ruminating animals ; whereas the same bitch, for a little time fed entirely with animal food, afforded a milk manifestly alkaline, and not spontaneously coagulating."* Such animals as feed upon other animals are well known to have their juices easily disposed to become alka- line ;f their flesh is rank and unsavoury .J AH those creatures which live upon prey have con- stantly a strong and fetid breathy Now a putrescency, or as Dr. Cullen ex- presses it, " an alkalescency, is the peculiar ten- * Vide Cullen, Mat. Med. vol. i. f Boerhaave, Aphor. 97. % Vide Hunter, Animal Economy. 5> Van Swieten, Commentar. HUMAN FLUIDS. 9$ dency of the animal economy ;"* which will be more easily understood from a consideration of the nature and generation of what are called the animal salts ; into which is converted a consi- derable portion of almost every thing ingested.f Even the strongest vegetable acids are by the vital powers converted into a neutral, or a sort of ammoniacal salts, which, in proportion to the time they are exposed to the action of the vessels, and the heat of the body, are rendered more and more subtle, approach nearer and nearer to an alkaline nature, and would at length become actually alkaline, were they not diluted, washed off, and corrected by acescent drink and diet.J If the aliment, then, be chiefly of the alkalescent kind, as most animal substances appear to be, it will conspire with the action of the body, and of consequence greatly increase this natural tendency of the fluids. Experience, indeed, shows that no person is able long to support a * Materia Medica, vol. i. p. 218. f Gregory, Conspectus Medicinse, ^ 529. \ Huxham, ut supra. 100 PATHOLOGY OF THE diet of flesh and fish alone, unless corrected by a proper proportion of vegetables, or of acids and acescent things. A confinement to animal food, with abstinence from recent vegetables, is generally admitted to be among the principal causes of scurvy. Upon the first establishment of the New- York State Prison, about 1797, before a regular system of internal management with regard to the diet of the house was adopted, an alarming scorbutic disorder made its appearance among the greater part of the prisoners in that institution. They had been confined for some time to a diet almost exclusively of animal pro- visions ; and without adverting to the source of the complaint with which they became affected, a variety of means was employed for its removal, but, as might have been anticipated, without effect. At the suggestion of Dr. Hosack, who shortly after this period was appointed the phy- sician to the establishment, the liberal use of recent vegetables was enjoined as indispensably necessary in order to check the progress of the disease,and for the purpose of restoring the health of the prisoners. The learned and experienced HUMAN FLUIDS. 101 Dr. Ferriar* found that many of his diabetic patients were rendered scorbutic, by a strict ad- herence to the exclusive use of animal food. Instances of a similar kind have fallen under the notice of Dr. HosACK.f The scurvy, it is well known, is much more frequent, and, indeed, almost epidemic, in cold and northern climates, where, from a scarcity of vegetables, the inhabit- ants are obliged to live principally upon flesh and fish. The diet of the Icelanders, which consists almost exclusively of animal matter, is universally productive of a train of obsti- nate cutaneous and scorbutic affections, which have been lately noticed by Dr. Holland.J The learned Dr. Lind$ has, on this subject, furnished us with a very remarkable story from Sinop^us.II " There are whole nations in Tar- tary who live altogether on milk and flesh. These people are never seized with the small * Medical Histories and Reflections, vol. iv. f MS. Notes on the Theory and Practice of Physic, \ Vide Eclectic Repertory of Philadelphia, vol. iii, ^ On Scurvy, p. 300. !| Parerga Medica, p. 311. 102 PATHOLOGY OF THE pox ; but, on the other hand, are subject to vio- lent scurvies, which at times sweep off as great numbers as the small pox does of other na- tions." A mixture of vegetable substances with our food, therefore, seems requisite towards the ge- neration of good chyle, and to correct the con- tinual alkaline and putrescent tendency of the animal fluids. The proportion of these, how- ever, will depend greatly on circumstances. The inhabitants of very cold countries, as Green- land, Lapland, and Hudson's Bay, can sustain a diet of flesh and fish, with much less impunity than those who reside within the tropics, or in hot countries, where the septic tendency of body is much greater; of consequence they are obliged to be much more abstemious of animal food, and live more on vegetable and antiseptic materials. All animal diet is more apt to excite and heat the body than vegetable ; and the reason is ob- vious : The salts of animals are chiefly volatile and alkalescent; but those of most vegetables are of a fixed nature and acescent ; and on this HUMAN FLUIDS. 103 account, when received into the blood, remain inactive and quiescent without much exciting the system: whereas the former, which are naturally active and somewhat volatile, and are rendered still more so by the heat of the body, not only excite a greater agitation in the fluids, but likewise irritate the solids, and stimulate the several series of vessels into quicker and more forcible vibrations. An excess of animal food, therefore, without a due proportion of vegeta- bles and acescent things, must needs prove un- suitable or incongruous to the constitution, and not only lead to scurvies and various kinds of eruptions, but also predispose the body to ardent inflammatory diseases, and to putrid, ma- lignant, and pestilential disorders, &c. With respect to acrid matters introduced into the body from without, many of them have long been suspected of being prejudicial to health. Acria ingesta, says Be G outer, si tarn rigida sint, ut vi vitee superari nequeant, venena nobis sunt : quae vero deficile subiguntur longas pertinacissimasque segritudines et dolores inferre solent: mitiora vero quandoque maxime appe- 104 PATHOLOGY OP THE tuntur, exhibentia, grata stimulantia. Talia sunt innumerabilia inusu humano, utacida, salina, aro- matica, alcalica, &c. quae omnia, si non nimis ve- hementia sunt, in corporibus robustis facile vin- cuntur; sed in debilibus diu ssepe latere possunt, maxime si simul eorum causam morbificam fove- ant : quas vero huic causa3 contraria sunt, medi- camenti titulo adhiberi possunt.* The body, however, is in some measure pro- tected against the admission of any thing of a heterogeneous nature, by the power of sensation, which, being readily excited into action by the irritation of any acrimony impressed, so con- stricts the mouths or orifices of the lacteals as to exclude many offending matters, except when so diluted and blunted as to become mild.f But this power is by no means absolute ; nor dothe lacteals possess that peculiar appetency, or discriminating faculty, for which some have contended: on the contrary, there are innumerable evidences that foreign matters can be conveyed into the blood * De Gorter, Tract, de Perspir. cap. vii. $5 11. f Gaubius, Patholog. ^ 297. HUMAN FLUIDS. 105 in their active state.* " A great many substances may enter the lacteals along with the chyle, even solids reduced to a fine powder."f Solutions of indigo and blue-stone are readily absorbed by the lacteals of a dog.J The lacteals and lymphatics, says Mr. Cruiksha]\ v k, take up the most irritating and stimulating substances.^ Pathologists have insisted much on the inju- ries resulting from an immoderate use of the aromatics. But the circumstances of their opera- tion are not, perhaps, clearly determined. We have reason, however, to suspect their noxious influence in those affections of the bladder, which, in advanced life, are connected with a tender- ness or preternatural sensibility of its neck, or perhaps some affection of the prostate gland. Common salt is generally supposed to be the most innocent of the whole class of acrids, and * Vide Smith, Inaug. Dissert, on Absorption, in Caldwell's Collection of Theses, vol. 1. Philadelphia. f Fordyce on Digestion. | Vide Dr. Musgrave's Experiments, in Philos. Trans. Abridg;, vol. v. ^ Anatomy of the Absorbing Vessels, p. 123. 14 106 PATHOLOGY OF THE indeed would seem to be a necessary stimulus to the process of digestion. But even this agreea- ble condiment, if too much accumulated in the habit, and particularly of such as are of a tender constitution, is capable of producing the most pernicious effects, as will clearly appear from the following remarkable case recorded by the late Dr. Peroival. " A young lady aged sixteen, tall, thin, and of a delicate constitution, though in tolerable good health, was advised to use sea water, on account of a strumous swelling and inflammation of her upper lip. She drank a pint of it every morning for ten days successively, which did not pass off freely by the usual evacuations. At the end of this period, she was suddenly seized with a large discharge of the catamenia ; was perpetually spit- ting blood from the gums, and had innumerable petechial spots on different parts of her body. Her pulse was quick, though full, her face pale and somewhat bloated; her flesh somewhat ten- der; she was often faint, but soon recovered her spirits. The flux from the uterus at length abated, but that from the gums increased to such HUMAN FLUIDS. 107 a degree, that her apothecary took a little blood from her arm. From the orifice blood continu- ally oozed for several days. At last an hemorrhage from the nose came on, attended with frequent faintings, in which she at length expired, choak- ed, as it were, with her own blood. Before she died her right arm was mortified from the elbow to the wrist. And it is further to be remarked, that though blood let from her some weeks be- fore she began the use of the sea water was suf- ficiently dense, yet that drawn in her last sick- ness was putrid and dissolved gore."* Physicians have frequently had occasion to complain of the bad effects of the alkaline salts both fixed and volatile, and, indeed, there are man} 7 indubitable and well-attested facts of their having produced in the human body putrid symptoms of various kinds.f Such effects have been particularly observed to follow the too free use of Mrs. Stephens's famous alkaline medicine. Haller observes of this medicine, * Percival, Essays, Medical and Experimental, vol. ii. f Vide Huxham, Essay on Fevers, &c. 108 PATHOLOGY OF THE that by long use it renders the blood alkaline and acrid, and brings on scorbutic and hectic symptoms.* As these salts are found to resist the putrefactionf of dead animal matter, it might appear a little surprising that they should be capable of producing putrid effects in the ani- mated machine; but the difficulty will in a great measure vanish when we consider, that they not only promote the dissolution, and, con- sequently, the putrefaction of the blood ; but further by their stimulating properties they cre- ate an excess of heat and motion, which accord- ing to Haller,J are among the principal causes of putridity in the animal economy. An acrimony is likewise generated when the body, in a sound state, is not duly supplied with the necessary nourishment ; and that the sooner in proportion as the vital power is stronger. * Sed in vivente etiam homine lixivi sales, qui Stephaniano medicamento efficaciam praestant, longo usu sanguinem alcali- num, acrem, scorbuticum, hecticumque reddiderunt ; ut etiam vesicas de cute elevaverit. Haller, Elem. Physiol, torn. ii. p. 90. f Pringle, Diseases of the Army, Append. \ Vide Elem. Physiol, torn. ii. p. 80. HUMAN FLUIDS. 109 The animal humours, in consequence of con- tinual heat and motion, naturally and constantly tend to a state of acrimony and putrefaction. One of the principal means employed by nature to obviate this dangerous tendency is the regular and daily supply which the system re- ceives of fresh and nutritious aliment. For the office of the chyle is not only to afford nutriment to the different parts of the body, but also to temperate, dilute, and correct the blood itself. When, therefore, the blood is for some time deprived of the necessary refreshment of this demulcent liquor, it naturally grows more acrid and putrescent ; to such a degree at least, as will be sufficient to render the whole mass, in a few days, unfit for any of the functions of life. In a person who has suffered hunger for a long time the blood and humours are attenuated and rendered more acrimonious, by which they incline to putrefaction ; and hence, all the secre- tions are rendered acrid and putrescent : what is expired from the lungs becomes so very fetid and disagreeable that the person is scarcely able 110 PATHOLOGY OF THE to endure his own breath.* Those who die of famine have their blood and all the humours first rendered highly acrimonious,! which not only corrodes the delicate vessels, and sometimes induces hemorrhages and effusions of blood in different parts of the body, but so injures or al- most destroys the tender fabric of the brain and cerebellum, as to produce intolerable pains, spasms, convulsions, acute fevers, attended with raging fury, and at length death itself. J * Ulis qui inediam patiuntur, et quorum sanguis novo affluente chylo non reficitur, sanguis per se interno calore dissolvitur et putrescit, hincque omnia, ex eo sanguine secreta, foetent et acria sunt, halitus olet, saliva labia et linguam rodit, sudor ingratus est, bilis et cffitera secreta irritant, et ipsas partes solidas, in quibus hospitantur, destruunt; nisi enim opportune novo affluente latice chyloso restaurentur, totum corruit. Schwenke, Hazma- lolog.Tp. 131. •j- The blood of those who die of famine becomes highly acri- monious, which begets fever, phrensy, and such a degree of putrefaction, as is utterly destructive of the vital principles. Huxham, id antea. | Ostendimus, etiam modico a jejunio fetere animam, etiam in purissimo feminse corpore. Sic lac continuo rancescit, et urin* intoleranda fit acrimonia. Sed diutius si inedia protracta merit, ab erosis ut videtur nervis, dolores non tolerandi nascim- HUMAN FLUIDS. 11 1 The use of hard and indigestible aliments, or such as are too tough for the individual constitu- tion, and insuperable to the powers of the body, will, in like manner, favour the generation of acrimony ; for it is easy to understand that the chyle, which is drawn from food of this character, will not only be less fit for nourishing the body, but also deficient in those qualities which are requisite to dilute and correct the acrimonious and putrescent animal humours. Hence, crudities and spontaneous corruptions from a want of proper chyle and nourishment. But moreover, this crude chyle not being either duly elaborated or expelled the body, must ne- cessarily of itself, by the heat of the blood, by repeated circulations, and continuing long there, become acrid and putrescent, together with the other juices of the body. It is to this source tur, et vasa rumpuntur, ut hasmorrhagijc narium superveniant, et sanguis in ventriculum avicularum effusus visus sit, inque intes- tina. Celeriter etiam mens emovetur, et merositas primo ctque. mentis pene alienatio, et epilepsia, inde demum, delirium, deinde plenus furor superveniat, mortemque fere prxcedat. Haller, Elem. Physiol, torn. vi. p. 167. 112 PATHOLOGY OF THE that the learned and practical Dr. Lind, in his excellent book on Scurvy, has principally attri- buted the production of this disease, so far as a sea diet is concerned in it. The scurvy, how- ever, is not peculiar to seamen or navigators. There are instances of its appearance in be- sieged towns. It occurs in low, damp situations, under the use of unalimentary food, or where the diet has been deficient in quantity, or of a low quality. Hence it is sometimes observed in the train of famine : such was the case in Paris, and other parts of France, in the year, 1 699.* In two recorded instances this complaint occur- red, in the most inveterate degree, in two old women who had subsisted, for more than three months, on nothing but bread and an infusion of tea, without any other ingredient whatever in their diet.f It is probably in this way, too, that bad and unwholsome food, ill ripened fruits of the earth, &c. do not unfrequently produce malig- nant and pestilential diseases : for the juices, " Blane, Diseases of Seamen, p. 191. i Milman, Inquiry into the Scurvy and Putrid Fevers, p. 25i HUMAN FLUIDS, 113 with which such supply the Mood, being cor- rupted, must necessarily form a fluid unfit both for nutrition and the animal secretions. Hence it is, that famine is not unfrequently suc- ceeded by pestilence, agreeably to the proverb, A0//U0C /WET* Mf/.lv. The blandness of our fluids is likewise de- stroyed both by an excess of motion, and by a want of motion in them; and thus the same effect will be produced, by two directly oppo- site causes. But nothing, perhaps, more favours the gene- ration of acrimony in the body, than the irre- gularities of those operations by which secre- tion and excretion are effected. The continual exercise of the animal functions produces, in the human body, an acrimony which is dissolved in the serosity of the blood, and is usually covered by bland nutriment continually supplied until carried off by the fluids denominated, for this reason, evcrementitious. If, however, the secre- tion or excretion of these noxious materials be prevented by any cause, so that they be retained in the animal economy, an acrimonious state of 15 114 PATHOLOGY OF THE the fluids necessarily follows. What this acri- mony is, we do not perhaps clearly and exactly know. It appears, however, to be partly of a saline, or, rather an alkalescent nature, and very probably contains some considerable admixture of septic particles. The generation of this acrimony in the fluids is much facilitated by an increase of heat and motion. Hence it goes on much more rapidly in fevers : and the changes then wrought upon the humours are rendered more conspicuous. It is certain, that the urine is always rendered more strong, fetid, and acrimonious, in propor- tion to the violence or rapidity of the circula- tion. In weak persons unaccustomed to exer- cise, it is limpid, pale, without smell, and not very salt to the taste ; but in a strong person, whose body is exercised by labour or motion, it is more red and fetid, and very saline. " If, there- fore, the motion of the blood through the vessels be increased, it will make the salts of the blood to become more acrid and volatile ; the oils also, will grow thinner, and be less mild ; these, again, will form a fresh stimulus to increase the circu- HUMAN FLUIDS. 115 lation, from the increase whereof they deduced their origin, -and the effect of a disease will increase the disease itself."* An acute and ardent fever is capable in a few days of so changing the texture of the blood, and corrupting the state of the humours, as to strongly incline them to a putrid and alkaline disposition. The blood, indeed, can never be so far corrupted as actually to become alkaline, whilst circulating in the vessels of the living body ; for death itself would first be produced by the destruction occasioned to the very small vessels, and the delicate contexture of the cere- brum and cerebellum. It may be questioned whether even the urine itself, which is the true lixivium of the blood, has ever been found to become actually alkaline, even in the most ar- dent, or most putrid fever; except, perhaps, where it has been a very considerable time in the bladder before discharged. Still, however, the blood and humours may become so far alkales- cent, that is, tend so strongly to an alkaline state, * Van Swieten, Coramentar. ^100. iJ6 PATHOLOGY OF THE as to render them unfit for the purposes of life and health. This tendency to an alkaline con- dition ought not to be confounded with that which is really alkaline. Nature has instituted two principal evacua- tions by which the blood is freed from these noxious and excrementitious parts. These are wine, and insensible perspiration both cutaneous and pulmonary. The urine is a sort 'of aqueous lixivium, or the ablution of all the oils and salts of the blood, that were rendered too acrid to be retain- ed with impunity in the circulation. It is of all our liquors the most easily putrescent,* and consists of a water containing salts and oils approaching to a state of putrefaction.f The urinary passages, therefore, are destined to carry off and cleanse the blood from those noxious, acrimonious, and putrescent matters which, if retained by any cause, would be productive of the most dangerous or fatal effects. The acri- mony thus induced, being increased by the heat y * Richerand, Elements of Physiology, p. 94. f Boerhaate, Elem. Chera. torn, ii. proc. 100. &^c. HUMAN FLUIDS. 217 of the body and the action of the vital parts every moment, would soon become intolerable to the more delicate vessel?, and dissolving to the humours, by a urinous and most pernicious quality. It soon shows itself in its effects on the tender vessels of the brain and cerebel- lum; for which reason those who die of a sup- pression of urine, have all the functions of the brain first disordered : they usually become comatose, delirious, are sometimes convulsed before death, but more generally go off quietly in a fatal sleep,* " A sufficient attention," says an eminent physiologist of the present day, "has not hitherto been given to the symptoms of a urinous fever, or affection occasioned by a too long retention of this liquid in the cavity of the bladder. I have frequently had occa- sion to observe, that no disease gave better marked signs of what physicians call putridity. The urinous and ammoniacal odour exhaled from the whole body in sickness, the yellow, greasy moisture covering the skin, the great * Van Swietejs, Commentar. 118 PATHOLOGY OF THE thirst, the dryness and redness of the tongue and throat, the frequency and irritation of the pulse, joined to the flaccidity of the cellular membrane; all indicate that the animal sub- stance is menaced with speedy and prompt decomposition."* The urine is likewise a humour interesting to the physician on many other accounts. The characters exhibited by this fluid are sometimes of considerable importance in distinguishing the nature and various states of any disorder. To those, too, who know how to form a judgment upon its properties and appearances, it is not unfrequently of assistance in deducing satisfac- tory indications of practice. A proper know- ledge of the nature of the principles which it carries off in certain circumstances, affords much information respecting the disposition of the constitution and the predominant principles ia the fluids of the human body. But the most considerable, perhaps, of all the evacuations from the human body, is the matter * Richerand, Elements of Physiology, p. 95. HUMAN FLUIDS. 119 of perspiration; the constant and equable dis- charge of which appears scarcely less necessary to life and health, than that of the urine itself. Its importance, too, rests not merely on its free- ing the blood from noxious or excrementitions matters; but it is further useful in maintaining a due equilibrium between the solids and fluids of the system ; in preserving the skin in a proper state of softness and pliability ; and, lastly, in being one of the great and principal means em- ployed by nature to diminish the effects of in- creased excitement, by carrying off the super- fluous animal heat, and thereby moderating the temperature of the body, and preventing the individual from receiving a degree of heat supe- rior to what is fixed by nature. It is owing principally to this latter circum- stance that animals can for some time endure without injury a temperature much higher than could have been supposed. The experiments of Tillet, of Fordyce and his associates, and of others, are well known.* By these experi- * Fide Rees' Cyclopxdia, art. Heat; also, Phil. Trans. 120 PATHOLOGY OF THE ments we learn, that persons have for a con- siderable time remained in an atmosphere heated to a temperature exceeding the boiling point of water. Nature has in this respect most amply displayed that system of general liberty, which she appears to have been so desirous of establishing in every thing relating to the animal machine. If the causes by which man is affected are various, his resources are equally multiplied: his temperature is adapted both for motion and repose ; he lives equally in all temperatures and in all climates. When in a cold medium his perspiration is diminished, and there is of consequence a less expenditure of animal heat ; the density of the air, too, be- ing greater, it has a more considerable contact with the blood in the lungs; whence more air is decomposed, and the evolution of caloric proportionably increased, which repairs the ex- penditures occasioned by external cold. On the contrary, when he finds himself in a hot cli- mate, where the air is more rare, and has of consequence less contact with the blood in the lungs, less of it is decomposed;, less caloric is HUMAN FLUIDS. }2l disengaged, and from the establishment of a more abundant perspiration, a proportionably greater quantity of heat is carried off by the continual evaporation from the surface. Hence it is, that the natural temperature of the living human body is nearly the same in all climates and at all seasons of the year. But to return ; That a moist vapour is continually exhaling from the surface of the body, is evident from a variety of circumstances. When from any cause the quantity of this perspired vapour is so much increased as to appear on the surface con- densed into a liquid or sensible form, it is then denominated sweat. But when it passes off in an invisible state, it is generally called insensible, or sometimes Sanctorian perspiration, in honour of Sanctorius. It would seem, however, to have been well known to Hippocrates, who, in a few words, observes, that the whole body both exhales and inhales '. " *Wv«6,v &&} sjwvoov Saov to a-*^*."* Many experiments have been made for the purpose of ascertaining the quantity of matter * Hippocrates, De Morb. Vulg. lib. vj. sect. vi. 16 122 PATHOLOGY OP THE perspired by the human body. The first who made any estimate of this considerable dis- charge was the celebrated Sanctorius,* who continued his observations for no less than thirty years. A similar set of experiments was after- wards made by Dodart,! in France, by Keil 3 J in England, by the learned De Gorter,& in Holland, by Robinson|| and Rye,U in Ireland, fcnd by Lining,** in South Carolina. On this 'subject, too, we have the still more recent and interesting experiments of CRUiKSHANK,ff Home,JJ Abernethy,^ and others. The quantity of matter perspired appears to differ very considerably according to circum- * Medicina Statica. f Haller, Elem. Physiol, torn. v. X Medicina Statica Britannica. ^ Tract, de Perspir. Insensib. || Treatise of the Animal Economy. 1F Med. Stat. Hybern. in Rogers on Epidemics? ** Philosophic- al Transactions. ft On Insensible Perspiration. IjX Medical Facts and Experiments. ^ Surgical and Physiological Essays, HUMAN FLUIDS. 123 stances. In the climate of Italy, Sanctorius ascertained it to be equal to five eighths of all the meat and drink taken into the body. It is unquestionably one of the most copious of the natural evacuations ; " and though it is some- times in greater or lesser quantity, as influenced by various causes, yet it can never be partially suppressed long, much less can it be entirely obstructed, without the greatest detriment to health. For should its defect for a short time be supplied by some more copious and increased evacuation, as it sometimes is by that of the urine; yet, towards perfect health, the inte- grity of all the animal functions, more espe- cially the natural evacuations, are requisite: there being somewhat thrown out of the body by each, which cannot so conveniently pass another way ;"f and, as Sanctorius very justly remarks of any other evacuation substituted for this, " ilia tollit copiam, sed relinquit malam * Si cibus et potus unius diei sit ponderis octo librarum, transpiratio insensibilis ascendere solet adquinquelibras cirtiter. Aphor. 6. f Lind, on Scurvy, p. 275. 124 PATHOLOGY OP THE qualitatem ;"* it diminishes the quantity, but leaves behind it the ill quality. The matter of perspiration is of two kinds., the aeriform and the aqueous. The former, which is small in quantity compared with the latter, consists of two different gases, to wit, the carbonic and the azotic.f The principles of the aqueous perspiration are, perhaps, nearly allied to those of the urine, only the former usually abounds more in a sort of oleaginous matter, from being thrown off from the blood after it has undergone a longer and much more elaborate ac- tion of the vessels, and when its principles are more thoroughly incorporated. But whatever may be the chemical analysis of the perspirable matter, it is evidently destined For excretion. As the health of the human bod v if greatly depends upon the due and regular separa- tion and expulsion of excrementitious matters, so the constant and equable discharge of the per- spirable materials must be of the first import- * Aphor. 19. 4 ACERNETHT, loC. tit. HUMAN FLUIDS. 125 ance, as it regards the healthy state of the body -„ for being a production of the last and most elaborate scene of animal digestion, the blood is hereby freed of what is consequently the most subtle and putrescent of the animal fluids. And it is certain that the perspirable humours, when retained long in the body, are capable of acquiring the most noxious qualities, and even putrefaction itself;* becoming highly acrimo- nious, which is increased every moment by the action of the vital parts. Hence arise various morbid affections, according to the habit of body, the constitution of the individual, and the influ- ence and determination of other causes. Of the noxious qualities of the matter of per- spiration, there can scarcely be more strong and positive proofs than those afforded by the expe- riments of Dr. Alexander. By these it is ren- dered evident that both the pulmonaryf and cutaneous% exhalations of the human body, even * Sanctorius, Aphor. 43. 46. 149. 176. Sfc. T Alexander, Experimental Essays, p. 53. | Ibid. Experimental Inquiry, cap. iii. 126 PATHOLOGY OF THE in the most healthful, are constantly replete with septic particles. It is owing principally and especially to this circumstance, that the air is frequently rendered so poisonous and corrupt in jails and all other confined and ill ventilated apartments, where a multitude of persons are closely shut up together, and constantly and repeatedly breathing the same air; whereby the whole atmosphere of the place soon becomes an accumulation of highly septic miasmata, which being rendered more active and virulent by heat and stagnation, at length assume a putrefactive contagion capable of producing the most malignant disorders. Hence it is, that air, often expired and replete with animal steams or exhalations, is, of all others, the strongest predisposing cause of putre- faction. The malignant and highly infectious nature of the air of close and crowded jails has long been known. " The most pernicious infec- tion, next the plague, (says Lord Bacos,) is the smell of the jail, when the prisoners have been long, and close, and nastily kept; whereof we have had in our time experience twice or thrice, HUMAN FLUIDS. 127 when both the judges that sat upon the jail, and numbers of those who attended the business, or were present, sickened upon it and died. Therefore it were good wisdom that in such cases the jail were aired before they be brought forth."* But it were superfluous longer to dwell upon the nature, effects, and importance of perspira- tion. It is intimately connected with health. Its influence in modifying the character of disease has long been known, and particularly demonstrated by those who have most success- fully directed their attention to the nature and cure of febrile, and of malignant and pestilen- tial diseases. Of all the various methods had recourse to in the treatment of the yellow fever, which has at different times prevailed in the United States, what may be denominated the * Bacon, Works, vol. ii. p. 49. Lond. ed. 1803. Vide also Blane, Diseases of Seamen ; Lind, Papers on Infection and Contagion ; Chisholm, Essay on the Malignant Pestilential Fever; Ibid. Letter to Hatgarth; Sir John Pringle, Dis- eases of the Army ; Ferriar, Medical Histories and Reflec- tions ; Hatgarth, on the Small Pox, &c. 128 PATHOLOGY OF THE sudorific plan appears to have been by far the most successful. Its decidedly beneficial effects were amply evinced in the long and extensive practice of the venerable Dr. John Bard, and of Dr. Samuel Bard, during the repeated visi- tations of that epidemic in the city of New- York, since 1743.* Its advantages over the mercurial plan of treatment were fully tested in the practice of Dr. HosACK.f A similar remark may be made concerning the importance of the sudorific method of cure in the typhoid peripneumonia, which, within these few years past, has so extensively prevailed in the eastern and middle states. " The prac- tice which has been by far the most generally * MS. Notes on Hosack's Lectures on Theory and Prac- tice of Physic and Clinical Medicine. f See also Dr. John Mitchill's Account of the Yellow Fever of Virginia ; Hosack and Francis' American Medical and Philosophical Register ; Facts and Observations, and Addi- tional Facts and Observations of the College of Physicians of Philadelphia ; Hosack, on the Yellow Fever of New- York, in Currie's Sketch of the Yellow Fever of Philadelphia; Currie, on Synochus Icteroides ; and other writers jn Mitchill and Miiler's Medical Repository, &c. HUMAN FLUIDS. 129 pursued, and considered of primary importance," observes the committee of the Massachusetts Medical Society, in their elaborate and interests ing Report, " is to produce early and long con- tinued sweating."* "By this evacuation we $iot only counteract the general vitiated state of the fluids, but we at the same time diminish, and in some cases, totally remove the local irritation which affects the lungs and other organs involved in this disease."f The observations of Dr. Williamson, made during the prevalence of the same disorder in North Carolina, lead to the same conclusions.:}: Thus far of the nature, causes, and effects of acrimony in general. To enter into a conside- * Vide Report of the Mass. Med. Society, in their Medical Papers, vol. ii. part ii. f Hosack, on the Peripneumonia Typhodes, in the Amer. Med. and Philos. Register, vol. iii. p. 452. \ Observations on the Malignant Pleurisy, in Amer. Med. and Philos. Register, vol. iii. p. 453 ; see also New- York Medical Repository ; New-England Journal of Medicine and Surgery ; Low, on the Epidemic Pneumonia, and other papers in {he Amer. Med. and, Philos. Register. 17 130 PATHOLOGY OF THE ration of the different kinds of acrimony that have been noticed in the schools, or to attempt to investigate their peculiar nature or specific quality, is deemed unnecessary. Nor, indeed, does it much signify as to the effect produced, what the acrimony is; acrimonious substances differing principally in a greater or less degree, and a more or less durable action.* They all appear to act as stimuli in irritating the solids and in exciting the action of the heart and arteries ; while at the same time they tend to destroy the healthy crasis of the blood and humours. But according to the different nature of each, peculiar medicines must be employed to correct and oppose the particular kind of acrimony. In general it will also be necessary to have re- course to a judicious employment of diapho- retic remedies; and to dilute and carry off the acrid materials, by the plentiful use of diluent, watery, and mucilaginous drinks and medicines ;f * Van Swieten, Commentar. f HoffbjaNj Medicin. Rational System, torn. iv. part. r„ cap. I, HUMAN FLUIDS, 131 with which it will, for the most part, be proper to mix acids, both vegetable and mineral, espe- cially where there is much excitement, where heat is to be moderated, a tendency to putrefac- tion prevented, or where the acrimony is of the alkalescent or putrescent kind. For it appears, that acids are both highly refrigerant and anti- septic ; and whether in these circumstances they produce their beneficial effects by diminishing sensibility and irritability ; or by correcting and changing the alkalescent salts ; or by condensing the humours and fibres; or in all these ways, is of little consequence.* It would also be foreign to our purpose to particularize the various degrees and sorts of acrimony or other morbid qualities which may be produced in the blood and humours by the introduction of various miasmata, or specific con- tagions. It may be observed, however, that each species of contagious particles produces a distemper of its own kind. Thus, the variolous effluvia produce the small pox, the morhillous * Burserius, Institutions of the Practice of Medicine, vol. 132 PATHOLOGY OF TH& Hie measles, the pestilential the plague, and so of other diseases propagated by specific contagions. But the extreme subtlety of contagious miasmata is such as to elude the examination of the senses ; of consequence we are unable to ascertain their peculiar nature or qualities, and must rest con- tented with being able to trace their operation and effects upon the living human body. One circumstance, however, connected with the ope- ration of contagions, and which particularly characterizes their action, is that wonderful fa- culty which they possess of transmuting many parts of the sound humours of the human body into a similitude with themselves ; and thereby diffusing through the blood a morbid quality of the same species and denomination with the disease from which they originally proceeded, But of this more will be said hereafter. How these subtle and invisible miasmata* when received into the body, are able so to injure the texture of the solids and fluids, and excite such wonderful commotions in the sys- tem, it is impossible to say. But that such effects may proceed from acrid poisons, plainly HUMAN FLUIDS. 133 appears from what happens to those bit by the haemorrhois, a Lybian serpent, the effects of which are so beautifully described by Lucan : Impressit dentes Haemorrhois aspera Tullo, Magnanimo juveni, miratorique Catonis. Utque solet pariter totis se effundere signis Corycii pressura croci, sic omnia membra Emis&re simul rutilatum sanguine virus. Sanguis erant lacrimse : quaecumque foramina novit Humor, ab his largus manat cruor: ora redundant, Et patulse nares : sudor rubet : omnia plenis Membra flaunt venis : totum est pro vulnere corpus.* * Pharsalize, lib. ix. v. 8ff#, Dissolved and Putrescent State of the Blood. Beside the several morbid conditions of blood which have already been noticed, there is another of a still more dangerous and compli- cated nature, and in which this humour more immediately tends to dissolution and putrefaction. 134 PATHOLOGY OF THE Such evidently appears to be the case in some scorbutics, and likewise in putrid, . malignant, and pestilential fevers. What degree of resolution in the blood is necessary to denominate this fluid putrescent, or putrid, or to what extent a putrescency of it may actually take place while circulating in the vessels of the living human body, is difficult to determine ; but such a degree of corruption, or putrefaction, as is by some authors spoken of, is certainly incompatible with life. As soon as the principle of animality or life abandons the body, it becomes immediately and totally influenced by physical laws, to which all inanimate and inorganized bodies are subject. It now performs a retrograde process, and be- comes decomposed. This decomposition, which is called putrefaction, totally destroys the natu- ral texture or consistence of the animal sub' stance, and produces an entire resolution of its component principles. The capacity of change in bodies is in a direct ratio with the multiplicity of their ele» mentsj so that the preservation or existence of HUMAN FLUIDS. 135 an organized being after death is protracted so much the longer in proportion as its con- stituent principles are less numerous and vola- tile.* It is for this reason that the fluid and softer parts of our body putrefy more readily than the solids or firmer parts. Putrefaction, indeed, never takes place in those animal sub- stances which contain only two or three ingre- dients, such as oils, resins, fyc. but they must always be more complicated in their texture or composition.f But however complicated the animal sub- stance, it does not putrefy without the presence of a certain degree of heat and moisture, which are the two great and essential requisites to putrefaction. Both of these requisites exist in the living system, and the former, too, according to the valuable experiments of Dr. Alexander, about that degree which is best calculated to promote the putrefaction of dead animal mat- ter. This process also advances with greater * Richkrand, Elements of Physiology, p. 462. } Thomson, System of Chemistry, vol. v. p. 770, 13(3 PATHOLOGY OF THJ5 rapidity in the open air ; " but exposure to air is not necessary, though it modifies the decom- position."* In this respect also, the human body is in that situation in which putrefaction would most readily take place ; for there is not only a constant application of the ambient air to the surface of the body, but it also enters deeply within by respiration ; and we are perpetually swallowing the same with our food and drinks ; so that it is not improbable that a portion of air may be intermixed or combined with our fluids, and even incorporated with the solids themselves. It is fully ascertained, that a small quantity of air may be gradually and slowly conveyed into the veins of an animal without producing death.f The celebrated Huxham, indeed, thinks it probable, that elastic air is sometimes even generated in the blood vessels, in putrid fevers. The learned Dr. Pringle was induced to believe, that several symptoms in the true scurvy might be owing to the action of air, within the vessels, * Thomson, ut supra. j Vide Pringle, Diseases of the Army, Append, p. Ixxxix. HUMAN FLUIDS. 187 either wholly detached from the blood and other humours, or but loosely connected, or imper- fectly incorporated with them. Since, then, the living body is constantly under all the necessary and most powerful cir- cumstances of putrefaction, and nevertheless the whole body of a living person has never been found absolutely putrid ; it necessarily fol- lows, that there is in life itself, independent of every other circumstance, a preservative power, which by its influence effectually resists putre- faction, and keeps the animated machine from total decomposition. It has been alleged, that the great and prin- cipal means by which the human body is pre- served untainted by putridity, is the constant elimination of putrescent matters from the sys- tem by the various excretions, and the daily succession of fresh materials from without, w r hich repair the expenditures and degeneracies occasioned by the actions of life.* This doubt- * Caro animata cur vivit et non putrescit ut morlua ? quia qnotidie renovatur. Sanctorius, Aphor. 80. 18 138 PATHOLOGY OF THE less has very considerable influence in this respect; but it is nevertheless of subordinate importance compared with the astonishing anti- septic powers of the vital principle. For it is well known, that a person may live under every situation most proper for putrefaction, without any sensible evacuation from the body, or with- out any thing being taken in for twenty-four hours ; and yet no general and absolute putridity shall take place. If, however, the same person had from some accident been suddenly deprived of life, and the dead body been retained for the same time in a temperature of 98 of Fahrenheit, a violent degree of putrefaction would have taken place. In order to establish general putrefaction in the body, it must be absolutely deprived of life. The living principle, whatever it may be, forms the most powerful antiseptic. It is this prin- ciple which, being universally diffused through- out the whole body, incessantly acts upon both the solids and fluids, and so long as it remains unimpaired effectually preserves the animal sub- stance from dissolution. It modifies., without HUMAN FLUIDS. 139 ceasing, the impressions of external agents ; and impedes the degenerations depending upon the actions of life, or upon the constitution itself. In proportion, therefore, as the vital power is either weakened or destroyed, the tendency to putridity in, the body will become more strong. Hence it is, that the strongest putrid symptoms generally appear so soon in all fevers, which are attended with early and universal debility, or with great and sudden depression of strength. The celebrated Beccher, in speaking of the causes which produce putrefaction in living bo- dies, elegantly observes : — " Causa putrefactionis primaria defectus spiritus balsamini est.* The blood in the aggregate possesses pre- servative properties, which it derives from the living principle it contains in common with the solids. The doctrine of vitality in this fluid, as we may learn from sacred history, has been entertained from the remotest antiquity ,f The * Beccher, Physica Subterranea, lib. i. i Vide Leviticus, chap. xviL 14D PATHOLOGY OF THE same opinion was entertained by Aristotle,*" and by many other ancient philosophers. This idea is also clearly expressed by Virgil : Ille rapit calidum fustra de vuluere telum : Una eademque via saDguisque animusque sequuntur.f The great Harvey, in his celebrated work on animal generation, expresses, in the most decided manner, his belief, not only that the blood is itself possessed of vitality, but that it is the im- mediate source of being and life to the rest of the system. Among other innumerable obser- vations to the same effect, he has the following. Clare constat, sanguinem esse partem genitalem, fontem vitse, primum vivens et ultim© moriens, sedemque anirnse primariam ; in quo (tanquam in fonte) calor primd, et praecipue abundat, vigetque ; et a quo reliquse omnes totius corpo- ris partes calore influeirte foventur, et vitam obtinent.J The first, however, who brought * De Hist. Anim. lib. iii. cap. 19. f Virgil, iEnid, lib. x. v. 486. t HaryeYj De Generat. Anim. Exerc.li. HUMAN FLUIDS. 141 this subject to the test of experiment, was Mr. John Hunter. His interesting and well direct- ed inquiries and observations ; and still more recently those of the able and ingenious Dr. Caldwell* of Philadelphia, have most satisfac- torily established this physiological fact. Since, then, the blood evidently appears to possess vital powers in common with the solids themselves, and since life and putrefaction are two ideas absolutely contradictory and incom- patible with each other ; it necessarily follows, that an absolute and universal putrefaction of this fluid can never take place during life. Of a quality of this active nature, inevitable death would be the immediate consequence. The term putrid, then, which conveys the idea of actual decomposition and death, is improperly applied to express any morbid condition of the vital fluid, which occurs during its circulation through the vessels. When, therefore, in particular diseases, the animal fluids undergo certain changes, tending * Experimental Inquiry on the Vitality of the Blood. 142 PATHOLOGY OF THE more or less to a state of putrefaction, this ten- dency to putridity ought not to be confounded with putridity itself. Such an incipient state of putrefaction in the humours will be more accu- rately expressed by the term putrescent, or pu- trescency, not as signifying a state of actual putridity, but a near approximation to such condition; that is, when the humours have so far degenerated that they would undergo de- composition and putrefaction with far greater ease, and more facility, than when in a sound and healthy condition. It is the opinion of some of our most dis- tinguished physiologists, that even the most healthful bodies have naturally and constantly some tendency to a state of putrefaction, which appears especially in the evolution and genera- tion of those saline and putrescent matters which are carried off by the natural excretions. If such be the case in health, it must obviously be much more so in certain diseases ; and that, per- haps, to such a degree as eventually at times to overcome the vital principle itself. Now, the seat of this affection appears to be more espe- HUMAN FLUIDS. 143 cially in the blood and other fluids. It is with the view of averting the evil that would neces- sarily ensue to the system at large, were the death and putrefaction of the blood permitted, that there are particular organs which are espe- cially destined to supply it with a daily influx of fresh materials, and preserve the whole in a reno- vated and living condition. It is obvious that all aliment, previously to its being able to nourish or transfer any restorative influence to the mus- cular or more solid parts, must, in the first place, make its way into the vital fluid. When deprived for any considerable time of this necessary re- freshment from cooling and nutritious aliment the blood and all the humours, as was before ob- served, become more acrid and putrescent. An animal that is starved to death does not appear to perish from inanition, or from an insufficient quantity of blood and other humours; but rather from a corrupt and putrescent state of them : in proof of which the use of water alone will keep it much longer from starving. But as water is entirely destitute of those mucilaginous principles, which are at present esteemed the 144 PATHOLOGY OF THE nutritive part of our food, it can scarcely be supposed that it produces this effect by affording any nourishment. It must therefore do it by diluting the fluids, or carrying off the noxious matters, and in this manner preserving them from this putrescent state. Dr. Lind* remarks, that he has always observed that the most rigorous of the Romish clergy, who are in the habit of frequent fasting, are greatly scorbutic, and re- markable for a fetid and most offensive breath, " Can we ascribe this sudden effect of fasting to a disease originating in the solids? Is it not more consonant to the laws of the economy, that the blood being deprived of regular sup- plies of mild and nutritious chyle, must be first affected by this loss, and that the solids suffer in a secondary way only."f But whether the putrefactive tendency be more strong in the solids or in the fluids, we may justly suppose that a quality of the active nature of putrefaction would quickly communicate its pernicious taint to eve- ry part of the corporeal frame. * On Scurvy, p. 328. •J Walker, on Small Pox. p, 108, HUMAN ELUIDS. 145 With respect to the peculiar or actual condi- tion of the blood in those diseases usually deno- minated putrid or malignant; though it can hardly be supposed, that a true and perfect putre- faction of this fluid, corrupting the whole mass, totally destroying its mixture, and resolving its component parts, can for the shortest time exist in the living body, it being repugnant to, and entirely incompatible with life ; yet an approxi- mation or rapid tendency to this state, or rather, what Professor Hosack, in his lectures on the theory and practice of physic, very aptly and judiciously denominates an incipient putrefaction, is compatible with life, though not with health, and evidently takes place in such diseases. This putrescency, or incipient putrefaction of the fluids in certain disorders, is evident, in the first place, from the appearances of the blood itself, when drawn from the vessels. The in- genious Dr. Milman, in his inquiry into the source whence the symptoms of the scurvy and of putrid fevers arise, very properly de- scribes the effects of putridity on the blood. a If putridity,'* says he, " actually took place 19 146 PATHOLOGY OF THE in the vital fluid, its effects would be, to break down the texture of its parts, as it does that of every body ; it must render it incapable of coa- gulation."* Now, this is a condition of the vital fluid very similar to what physicians have noticed in certain diseases, particularly in putrid, malignant, and pestilential fevers ;f in some scorbutics;}: and in the putrid,^ or pete- chial feverll of small pox; in all of which the crasis of this fluid is much injured and dissolved. The consistence is very different from the ordi- nary appearance of healthy blood, its texture * Milman, Inquiry, p. 55. f In rnorbis putridis dissolutio cruoris quoque advertitur, prcesertim pestis specie, in quibus non coagulatur sanguis, sed gangrsenosus et putridus reperitur ; quod etiam in eo sanguine observatur, qui post protractam inediam putridus et alcalinus factus est. Schwenke, Hozmatolog. p. 129. % Vide Huxham, Essay on Fevers ; Ibid. De Aere et Morb. Epidem. 55 Walker, on Small Pox, p. 109. Sec. || Nam in tanta pestilentia (scil. variolas,) sanguinis crasis dissolvitur penitus, et maxime putrescunt humores : imo cruor emissus, putris instar saniei, diffluit; nee ut solito, in frigore coagulatur. Huxham, De Aere et Morb. Epidem. vol. i. p. 105. HUMAN FLUI&S. 147 being so much weakened, or broken down, that either the coagulum is very loose, or it does not coagulate at all, or show any disposition to sepa- rate into crassamentum and serum as usual, but the whole remains quite fluid and dissolved. Huxham* assures us, that blood of this charac- ter always putrefies very soon. That acute and accurate observer, the late Dr. Fordyce, has noted the appearances of the blood through almost all the different stages of a putrid fever. In the beginning, says he, when the putrefaction has not gone to any great length, if blood should happen to have been taken from the arm, the coagulum is loose and easily broken, the serum being hardly of a browner colour than common ; but it becomes much more so when the putrefaction is fur- ther advanced. In a still further degree it is red:f in this case, continues he, on examin- ing the red particles with a microscope, many of * Essay on Fevers, p. 42. t See also Huxham, De Aere et Morb. Epidem. ; and like- wise his Essay on Fevers. i48 PATHOLOGY OF THE them are found diminished in size, and not regu- lar spheres, or oblate spheroids ; some have the appearance of being broken in two, and look like half moons. If the putrefaction goes on still further, there is hardly any distinction be- tween serum and coagulum.* " Blood being drawn in the beginning of putrid diseases," says Dr. Shebbeare, " the crassamentum, though very rubicund, scarce adheres together ; in the process of the disorder it becomes still of a looser texture, and more putrid hue, till in some very desperate cases, it is not better than a sanies or putrid ichor."f Beside these several morbid appearances, some justly celebrated physicians, and more particularly Vander M*Ej$ Fernelius,6 Mor- * Fordyce, Third Dissertation on Fever, part i. p. 92. f Shebbeare, Practice of Physic, vol. ii. p. 169. $ De Morbis Bredanis, p. 14, as quoted by Van Swieteiv. ^ Sanguis qui per febres putridas detrahitur, sspe animadver- titur non solum fcetidus et graveolens, sed et putridus adeo ut nee sibi cohserere nee concrescere queat, omnibus scilicet ejus lib ris putre dine consumptis. Ferseuus, De Febribus, cap. v, p. 246. HUMAN FLUIDS. 149 ton,* Sir John Pringle/J- and others, have even mentioned the absolute fetor, or offensive smell of the blood recently drawn. The putrescent state of the fluids is further evinced by A loathing of animal food, nausea, vomiting, thirst, and a desire of acids. By hemorrhages from various parts, without symptoms of increased impetus. By certain spots or marks called petechia?., maculae, and vibices, which are generally sup- posed to be owing to the effusions of dissolved blood below the skin or cuticle.! * Denique notatu dignissimum est, quod mihi nuperrime videre contigit, sanguis feminai eujusdam, febre maligna labo- rantis, per phlebotomiam detractus adeo fcetebat, ut ex ejus tetro odore tarn chirurgus quam adstantes in animi plane deli- efuium inciderint. Morton, Pyretolog. p. 2G. f On Jail or Hospital Fever, p. 837. X Hse macula oriri videntur ab infractis, aut dissolutis, san- guinis globulis, arteriolas serosas intrantibus ; dumque ibi hserent, petechias formant, aut vibices. Pestiferje semper sunt, quod cruorem putridum esse, aut niaxime solutun., denotant: imo- adeo sxpe dissolvitur sanguis, ut profusse subsequantuv hemor- rhagic. Quod quidem scovbuticis quoque accidit crebro, ciltr* 150 PATHOLOGY OF THE By the fetor of the breath, urine, and per- spiration, together with the cadaverous smell of the whole body. By the peculiar kind of acrid or biting heat that is commonly experienced on touching the skin of persons labouring under putrid malig- nant fevers. The heat at first seems inconside- rable, but on continuing the hand a longer time upon the skin, a disagreeable, pungent, or sting- ing sensation is felt in the fingers, which even remains some few minutes after they are removed from the sick. This fact has been particularly noticed by Sir John Pringle,* and, as he can- didly observes, by Galen long before him. The same, however, had also been distinctly remark- ed by FERNELIUS.f ne vel minima febris signa adsint, etsi totus fere corporis habitus innumeris violaceis maculis inficitur; qui tamen mox. ac ne quidem tale quid somniantes, funesto sjepe sanguinis fluxu corripiuntur : iste tamen cruor nunquam, more solito, concrescit. Huxham, De Atrt et Morb. Epidem. vol. i. p. 116. * Pringle, on Jail or Hospital Fever, p. £92. f Calor in febre putrida non mitis ac blandus, sed acer, mordax ft qui tangentis sensum acriter feriat, non ipso invasionis initio, HUMAN 1'LUIDS. 151 Lastly, by the surprisingly great and speedy corruption that generally takes place in bodies dying of putrid, malignant, and pestilential diseases.* To what has been already said upon the na- ture and effects of putrescency, it may not be improper to subjoin the following observations of Dr. Gregory : Q,uandoque autem massa sanguinis putrescit multum, non modo acris fit, sed solvitur quoque, segre cogitur, et tenue et rarum crassamentum ostendit : quin et ipsse particular rubrae dilabuntur et franguntur. San- guis vero sic solutus et acer, turn propter salem evolutum, turn propter gluten suum rancidum et putridum, vasa sua stimulat, eroditque, et ex iis elabitur; et maculas primo rubras, postea livescentes Tel nigrescentes, tumores, ulcera vix sanabilia nisi tempestive putredini occurratur, sed vel in augmento, vel in statu, idque maxime si diutius corpori manus insideat. Fernelius, De Febribus, cap. vii. p. 249. * Huxham, De Aere et Morb. Epidem. ; Ibid. Essay on Fevers ; Hosack, MS. Notes on the Theory and Practice of Physic and Clinical Medicine. 152 PATHOLOGY OF THE sanguinis profluvia ab omni corporis parte vix compescenda, et foetorem insignem et intolera- bilem halitus et omnium excretionum facit; et laxitatem solid arum partium, summamque debi- litatem, (quia gencri nervoso veneno est,) et mortem tandem, talis corruptio inducit* The subsequent quotation from the learned Baron Haller, supersedes the necessity of any further remarks on this part of the subject; Q,ua3 motus musculorum, eadem febris facit, qusecunque ejus origo fuerit : dum sanguinis motum vehementius augeat. Putrescunt in febre humores, et in variolis, et in petechiali genere, flavaque ilia insularum antillarum peste, sanguis fcetidus per os et nares erumpit. In variolis confluentibus penetrabilem foetorem seepe ex- pertus, nullis aceti in planas patinas expositi contrariis vaporibus satis emendare potui. Ip- sum inde lac ebutyratum, et citri succus putrescit. Fcetent ante mortem, qui febre paludosa pu- trida laborant. Foetorem combustarum sole- arum similem, adeoque alcalinum, in malignis, * Gregory, Conspectus Medicine. ^ 5S4. HUMAN FLUIDS. 153 sudoremque enormiter olentem Segerus obser- vavit. Funestus cadaveris odor in hominibus peste laborantibus percipitur, qualem ab aegro ipso perceptum memini in bibliopola propriae mortis certa praesagia dedisse : is autem in peste ordor inficit, lateque malum propagat. Mira virulentia humorum in hominibus est, qui peste pereunt, et sanguis ipse fcetet, et vapor destillati de pestilente bubone puris quasi fulminis ictu male curiosum medicum prostravit. Corpora hominum peste extinctorum, aut paludosa febre, continuo putrescunt.* The causes of putrescency in the animal fluids, which come next in order for considera- tion, being in almost every respect the same with those of acrimony, which have been already sufficiently dwelt upon, it would be unnecessary again to enumerate them in this place. A few observations, however, upon some of the princi- pal ones may not be improper. Neither the whole, nor any part of the living human body, notwithstanding it has some of the * Haider, Elem. Physiol, torn. ii. p. 85- 20 154 PATHOLOGY OF THE most powerful causes of putrefaction interwoven with its very existence, ever runs into this state during life, except previously inclined thereto by the operation of some powerful cause or causes, though these may not always be disco- verable. On the contrary, when life is extinct, almost the whole animal substance invariably and spontaneously putrefies, unless prevented by the influence of forcible agents. But as it respects matter and construction, the animate and inani- mate body are exactly the same. That the for- mer, therefore, is less inclined to putridity than the latter, must be owing to something which it enjoys during life, but is deprived of when dead. Now as to life itself, we are totally ignorant of its nature or essence. We know not in what it consists, nor even the powers of which it is pos- sessed. Respecting its action or mode of pro- ducing its various effects, no satisfactory expla- nation has yet been given. Instead, therefore, of indulging in ideal conjectures concerning things which we do not understand, let us rather Tendeavour to seek some other cause why the animal body is so seldom attacked by putrefac- HUMAN FLUIDS. ]55 tion during life ; and perhaps this eause, if it can be discovered, may Ihrow some light upon the reasons why the body sometimes does suffer by it. It was on a former occasion remarked, that one of the principal means employed by nature in obviating or retarding the tendency of ani- mals towards a putrid state, is the regular and constant supply which the blood daily receives of fresh and antiseptic materials, taken in by way of food. But a second, and perhaps still more powerful cause, is motion.* There may be, and unquestionably are, many other subordi- nate causes which co-operate with these two, but as their power is probably much more limit- ed, we shall pass them over without any particu- lar notice, and at present only consider the effects of irregularities of the animal motions, which, we believe, will of themselves be found fully adequate to the production of putrescency, * Quamdiu asquabili motu per vasa circumducuntur humores s nulla nascitur in corpore putredo, omne illud, quod inciperet dispo- ni ad putredinem, solitis corporis viis e'liminatur, Vajv S vvietejv, Commentar, 156 PATHOLOGY OF THE without the existence of putrid miasmata, or any other external power. That motion is one of the great and principal agents by which bodies or substances of various kinds are preserved from a state of putrescency, is a truth confirmed by daily observation ; and the reason of its being so strong and universal an antiseptic will perhaps more fully appear by a little attention to the phenomena that accom- pany bodies while putrefying. A great variety of repeated experiments and observations have demonstrated it to be an inva- riable law of nature, that an intestine, or as it is more usually styled, a fermentative motion must necessarily precede a state of putrefaction in dead animal and vegetable substances. But in order that this fermentative motion may more readily take place, it is necessary that the parts of the body upon which it is to operate, be in a state of repose among themselves ; for if they be put in motion by any external cause, or im- pelled by any vis a tergo, in the manner of the circulating fluids of the animal body, they will be much less susceptible of motion from any HUMAN FLUIDS. 157 oilier cause, which, previously to its being able to operate upon them, must first overcome the motions impressed upon them #6 extra,or destroy the force by which they are already urged. Hence the greater purity of running water, and that of the sea when agitated by the winds, in comparison of the same when stagnating. The ocean is in a state of perpetual flux and reflux; and by this motion is it preserved fresh. It is only in marshes and some stagnating lakes that water is ever found putrid, according to the common expression ; for water of itself appears to be a non-putrescible substance, and it is only by being impregnated or mixed with other cor- ruptible matter that it actually becomes putrid. Since then it appears that a state of rest is favourable to putrefaction, and a state of motion unfavourable to it; and since it is certain that independent of the loco-motive faculty of a living body, all its various pads are in perpetual motion among themselves, we may very justly conclude, that motion is one of the causes of the preservation of the animal body from putrefac- tion during life, and the loss of this vital motion 158 PATHOLOGY OF THE one of the causes of its destruction or corrup- tion after death. The blood is constantly per- forming the rounds of the circulation, which, when properly regulated, evidently possesses a power of preventing its putrefaction ;* yet this motion appears to be endowed with such a power only, in consequence of its enabling the vital fluid to throw off such matter as would corrupt it, if retained too long in the vessels ; and also by counteracting the fermentative motion, which is found to be absolutely necessary towards pro- ducing putrefaction in dead animal matter.f * On this subject, showing that the circulatory motion of the- blood impedes its putrefaction, the reader may consult Haller's Elementa Physiologic, torn. ii. lib. vi. sect. iii. ^ ix. et xiv. ; and also Dr. Alexander's Experimental Inquiry, to which able and interesting work, the author is particularly indebted for many ob- servations. f Si accuratius rationem exquisiveris, qua motus putredinem avertat, duplicem inveniemus. Nam progressivus motus intes- tino resistit, neque adeo sinit fermentationem obtinere, neque fere putredinem. Deinde vitalis motus sanguinis, organorumque sani hominis, huraores putrescibiles continuo expedit et abigit, et quae ad urinosam acrimoniam accedunt, ea per cutaneam per- apirationem, per urinam, cumque alvi fiecrbus expurgat et ejicit Haller, Elem. Physiol, torn. ii. p. S08. HUMAN FLUIDS. 159 The blood and other juices will easily putrefy, either in the whole or any part of the body, by being entirely deprived of their accustomed motions.* If, for example, by a tight ligature or other means, the vital or circulatory motion of the blood be stopped in a leg or an arm, a mortification soon follows. The same thing frequently happens when from an internal ob- struction, the influent juices are denied admis- sion into any member or part of the body ; but in both these cases the most obvious cause is the loss of motion. In short, the tendency of the animal fluids to corruption or putrefaction will, ceteris paribus, be greater or less according to the degrees of motion impressed upon them by the heart and their contractile vessels. We have hitherto insisted upon the power of motion and antiseptic food, in retarding or counteracting the putrescency of the animal fluids ; but the motion all along alluded to is that called vital or involuntary, which must not be con- * Nam in toto humano corpore, et in singulo artu, continue liiimdres putrescant, quando motus suppresSus est. Halxer. 160 PATHOLOGY OF ttlE founded with the intestine or fermentative ; the former tending to the preservation, and the lat- ter to the destruction of the animal body. But although the vital motions, when properly regu- lated, assist in preserving the humours from pu- trefaction, yet when they run to either extreme., they actually produce a contrary effect ; that is ? putrescency will be brought on by the circula- tion being rendered too slow,* or too rapid,f and thus the same effect will be produced by two directly opposite causes.J The circulation being too much retarded, the blood will be less able to throw off such excre- * Sublato motu progressive* sanguinis subita putredo nasci- tur. Haller, Elem. Physiol, torn. ii. p. 308. f Longe autem citius in putredinem abeunt humores anima- lium, si valide moveantur, si valido cursu, vel alio labore, quis corpus exercuerit. Quam olidus sudor, quam acris et fcetida redditur urina, dum febris acuta lactantem prehendit raulierem ? Nisi plurimum potet, intra paucas horas lac fiet tenue, subfla- vescens, salsum, odoris suburinosi. Van Swieten, Commen- tar. ^ 80. J Motus nulltis, et motus nimius liquidorum nostrorum, pro- ducunt putredinem ; sicque bine, Diseases of Seamen, HUMAN FLUIDS. 169 But although we, who inhabit the colder and better ventilated parts of the world, have little reason to dread a putrid contagion being gene- rally diffused through the atmosphere, so as to contaminate any considerable region of it; yet are we assured that it has often infected indivi- duals who have either come into actual contact with it, or unintentionally approached too near it, when in a confined and highly concentrated state. Neither are we to infer that all parts of the world are equally exempted from the influ- ence of this effluvium. In many hot climates, where an uninterrupted calm almost perpetu- ally reigns, the exhalations arising from animal putrefaction may accumulate in prodigious quan- tities, and remain undisturbed in the atmosphere till it is heightened by the heat of the sun into the most malignant qualities; and gradually contaminating surrounding objects, it is propa- gated from one to another, till it spreads to a considerable distance, tainting every thing in its way, and loading the atmosphere itself with the semina of disease and death. The propagation of such an infectious atmosphere is beautifully 22 170 PATHOLOGY OF THE described in a passage of Lucretius, De Rerum Natura, which has, on a similar occasion, been quoted by Dr. Hosack : Proinde, ubi se coelum, quod nobis forte venenum, Conmovet, atque aer inimicus serpere coepit ; Ut nebula ac nubes, paullatim repit, et omne, Qua graditur, conturbat, et inmutare coactat. Fit quoque, ut in nostrorum quom venit dinique coelum., Conrumpat, reddatque sui simile, atque alienum. Luc. lib vi. v. 11 17, But when the heaven, of poisonous power to us. First moves remote, its hostile effluence creeps Slow, like a mist or vapour ; all around Transforming as it passes, till, at length, Reach'd our own region, it the total scene Taints, and assimilates, and loads with death. Good. But after all it may be much questioned whether mere putrefaction, or the effluvium of putrid and decomposed animal and vegetable matter, is not very distinct from the gaseous and subtle matter constituting a specific contagion ; more especially when we consider that the lat- HUMAN FLUIDS. 171 ter always produces the same peculiar and spe- cific affection ; whereas the diseases proceeding from the former source have been generally observed to assume great diversity of character. Dr. Chisholm, whose works will stand as lasting monuments of learning and medical science, is, after much inquiry and reflection, as he tells us, fully convinced, that the product of animal pu- trefaction never acquires a pestilential influence ; i. e. that it is, under any circumstances, wholly inadequate to the production of pestilence, or the true plague, for which it has been so gene- rally censured.* This distinguished philoso- pher is of opinion, that the effluvia from dead animal bodies, passing through the natural pro- cess of putrefaction, when applied in a concen- trated state to the bodies of living animals, may act as poison, producing in the living animal frame, fever, perhaps, but incommunicable, or incapable of propagation by contagion.f * Chisholm, on Contagion, in the Edinburgh Medical and Surgical Journal. 1810. f Ibid, toe, cit.^ 372 PATHOLOGY OF THIS But although the diseases produced by animal putrefaction never arise to the malignity of a true plague, the evidences are too numerous and too strongly supported to doubt that it has often produced putrid, or fatal distempers in particu- lar bodies exposed to its action, and sometimes perhaps even putrid epidemics, particularly in hot, or tropical countries.* Tt seems also to be an established position, that in proportion to the foulness of a place, or rather to the quantity of putrid vapours float- ing in its atmosphere, it will be more or less subject to pestilential fevers, or to receive and multiply the leaven of a true plague introduced into it either by merchandize or other means. Contagious and pestilential fevers appear to be always rendered more malignant in a foul than a pure atmosphere. The facility, too, with which they are communicated through the medium of a vitiated atmosphere, and the rapidity with which they are propagated would seem to war- rant the idea, that the air surrounding the sick * Vide Forestus, Mead, Pringle, Lind, Biane, be. HUMAN FLUIDS. 17$ becomes assimilated to the nature and character of the specific virus emanating from their bodies,, by which means the poison is both multiplied and more widely diffused, so as greatly to increase the chance of communication to other persons. The malignity and increased mortality attending the plague of Athens,* and the pestilential fever of Rome,f u c. 289, would appear to have been owing principally to the great filth occa- sioned, not only by other circumstances, but more particularly by the great crowds of people^ and by the large number of cattle of every description brought in for shelter from the coun- try. This circumstance, attending the propa- gation of fevers communicable by a specific contagion, has been most ably and clearly illus- trated by Dr. Hosack, in his letters to Dr. Chisholm, on the subject of contagion. Speak- ing of the laws which govern the communication and propagation of plague, yellow fever, malig- nant dysentery, and the various forms of typhus, * Vide Thuctdides, lib. ii. ; Diod. Sictlus, lib. xiL cap. 14, f Livy, Hist. Rom. lib. iii. cap. P. 174 PATHOLOGY OF THE Dr. Hosack remarks, that " these diseases are only in general communicable through the me- dium of an impure atmosphere : in a pure air, in large and well ventilated apartments, when the dress of the patient is frequently changed, all excrementitious discharges immediately re- moved, and attention paid to cleanliness in ge- neral, these diseases are not communicated, or very rarely so, from one to another. But in an impure air, rendered so by the decomposition of animal and vegetable substances, as takes place in low marshy countries, or by concentrated hu- man effluvia, as in camps, jails, hospitals, or on ship-board, they are rendered not only extreme- ly malignant and mortal in themselves, but be- come communicable to others who approach the sick, or breathe the same atmosphere, which has become assimilated to the poison introduced, in so much, that the same specific disease is commu- nicated, whether it be the plague, yellow fever 9 typhus, or dysentery"* * Vide Amer. Med. and Philos. Register, vol. ii. ; and also the Edinburgh Medical and Surgical Journal. 1809. HUMAN FLUIDS. 175 Particular states of the atmosphere also fa- vour the production of putrid diseases. This invisible fluid, it is well known, is constantly and indispensably necessary to animal life; and as we are perpetually in contact with, or surround- ed by the same, and likewise swallowing it mixed with our aliments, as well as inhaling it every moment of life into the lungs, it is plain that the air itself, and of consequence any contagion or impurities inherent therein, may easily enter the body in considerable quantities, so as to pe- netrate every part of it. For this, as well as for other reasons, it has always been customary to consider a pure and wholesome air as one of the greatest sources of health, and its various changes, or impurities, one of the most frequent causes of disease.* Agreeable to which, whenever putrid diseases have become epidemic, and no visible i* Toleri eTg £,v &vnra!i Ctf/ACLTl jw.i^Bivrog, oftoiot nan 01 7rv£not ywovp&t. Hippocrates, De Fla- tibus. HUMAN FLUIDS. 177 did not hesitate to declare, that although he had carefully attended to the manifest qualities of the air, he had made no progress in discovering the causes of epidemical diseases; having re* marked, that in different years, which perfectly agreed as to the manifest temperature of the air, the prevailing diseases were very different, and vice versa : so that he was led to conclude that they depended upon some secret or invisible quality in the air, which we have not yet, and perhaps never shall be able to obtain the smallest knowledge of.* But notwithstanding that we * Quamvis autem diversas diversorum annorum habitudines s quoad manifestas aeris qualitates, maxima qua potui diligentia notaverim, ut vel exinde causas tantas epidemicorum vicissitudi- nis expiscarer, ne tamen ne hilum quidem hactenus promoveri sentio ; quippe qui animadverto annos quoad manifestam aeris temperiem sibi plane consentientes, dispari admodum morbo- rum agmine infestari, et vice versa. Ita enim se res habet Vari