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The Project Gutenberg eBook, A Mechanical Account of Poisons in Several Essays, by Richard Mead This eBook is for the use of anyone anywhere in the United States and most other parts of the world at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org. If you are not located in the United States, you'll have to check the laws of the country where you are located before using this ebook. Title: A Mechanical Account of Poisons in Several Essays Author: Richard Mead Release Date: October 3, 2016 [eBook #53202] Language: English Character set encoding: UTF-8 ***START OF THE PROJECT GUTENBERG EBOOK A MECHANICAL ACCOUNT OF POISONS IN SEVERAL ESSAYS*** E-text prepared by RichardW and the Online Distributed Proofreading Team (http://www.pgdp.net) from page images generously made available by Internet Archive (https://archive.org) Note: Images of the original pages are available through Internet Archive. See https://archive.org/details/mechanicalaccoun00mead A Mechanical Account of Poisons in Several Essays, by Richard Mead (Second Edition, 1708). A Mechanical Account OF P O I S O N S In Several E S S A Y S. BY RICHARD MEAD, M.D.F.R.S. And Physician to St. Thomas’s Hospital. The Second Edition, Revised, with Additions. LONDON: Printed by J. M. for RALPH SMITH at the Bible, under the Piazza’s, of the Royal Exchange, Cornhill. 1708. To T HE P RE FA C E give an exact and particular Account of the Nature and Manner of acting of Poisons, is no easie Matter; but to Discourse more intelligibly of Them than Authors have hitherto done, not very difficult. One may without much Pains shew their Effects to be owing to something more than the bare Qualities of Heat or Cold; and Discover the Footsteps of Mechanism in those surprizing Phænomena which are commonly ascribed to some Occult or Unknown Principle. But to Unravel the Springs of the several Motions upon which such Appearances do depend, and Trace up all the Symptoms to their First Causes, requires some Art as well as Labour; and that both upon the account of the Exquisite Fineness, and marvellous Composition, of the Animal Machine in which they are Transacted, and of the Minuteness of those Bodies which have the force to induce in it such Sudden and Violent Alterations. I have attempted somewhat this way in the following Essays; in which I do not promise Methodical, and Finish’d Treatises, but only some short Hints of Natural History, and Rude Strokes of Reasoning; which, if put together, and rightly Improved, may perhaps serve to furnish out a more tolerable SPECIMEN of the DOCTRINE of POISONS, than has yet been Published. The First Draught of this small Piece, I made some Years since, Entertaining my self at Leisure Hours, with Experiments on Vipers, and other Venomous Creatures; Examining now and then the Texture of Arsenic, Mercury Sublimate, and the like Malignant Substances; Turning over what Authors had said on the several Subjects, and making such Remarks as from Time to Time Occurr’d. There continued Enquiries made up at last, Three or Four short Discourses; which, when I began to Digest into Order, the Increase of Business contracted the Intervals of my spare Time; and the Diversion of such Studies quickly giving way to the Severity of more Necessary Labours, They were quite thrown by, Till Talking not long since with Dr. Areskine, concerning the Viper, I took Occasion to review my scattered Papers, and confirm my Reasonings by New Experiments. He very readily offered Me His Anatomical Observations; These I have put at the End of the First Essay; Which do not promise a Complete Dissection of the Animal, but chiefly shew the Make of those Parts which are concern’d in the Poison. My Design, in Thinking of These Matters, was, to Try how far I could carry Mechanical Considerations in Accounting for those Surprizing Changes, which Poisons make in an Animal Body; Concluding (as I think, fairly) that if so abstruse Phænomena as These did come under the known Laws of Motion, It might very well be taken for granted, that the more obvious Appearances in the same Fabrick are owing to such Causes as are within the Reach of Geometrical Reasoning; And that therefore as the first Step towards the Removal of a Disease is to know Its Origin, so he is likely to be the best Physician, who having the same assistance of Observations and Histories with Others, does best understand the Humane Oeconomy, the Texture of the Parts, Motions of the Fluids, and the Power which other Bodies have to make Alterations in any of These. Nor indeed ought any One to Doubt of This, who considers that the Animal Compages is not an irregular Mass, and disorderly Jumble of Atoms, but the Contrivance of Infinite Wisdom, and Master- piece of that Creating Power, who has been pleased to do all Things by Establish’d Laws and Rules, and that Harmony and Proportion should be the Beauty of all his Works. It were therefore heartily to be wish’d, that those Gentlemen who are so much afraid of Introducing Mathematical Studies, that is, Demonstration and Truth, into the Practice of Physick, were so far at least Instructed in the necessary Disciplines, as to be able to pass a true Judgment, what Progress and Advances may be made this way; They would not then perhaps Decry an Attempt of so much Moment to the Wellfare of Mankind, as vain and impossible, because it is difficult, and requires Application and Pains. It is very evident, that all other Methods of Improving Medicine have been found Ineffectual, by the Stand it has been at these two or three Thousand Years; and that since of late Mathematicians have set Themselves to the Study of it, Men do already begin to Talk so Intelligibly and Comprehensibly, even about abstruse Matters, that it may be hop’d in a short time, if Those who are Design’d for this Profession, are early, while their Minds and Bodies are Patient of Labour and Toil, Initiated in the Knowledge of Numbers and Geometry, that Mathematical Learning will be the Distinguishing Mark of a Physician from a Quack; and that He who wants this necessary Qualification, will be as Ridiculous as one without Greek or Latin. I have, as to what regards the Animal Oeconomy, Referr’d as much as I could to the Works of Bellini, which have brought great Light into the Dark Regions of Physick, and Taught Us to argue clearly and consistently, instead of Amusing our selves with Unintelligible Words or Precarious Hypotheses. The Dissertations of Dr. Pitcarne, who is the Honour of his Profession in Scotland, are a Convincing Proof of the Advantage of such a Mechanical Way of Reasoning; nor could Malice it self deny This, were not Ignorance in Confederacy with it, which will secure any One from being Benefitted by the most useful Demonstrations. Notwithstanding This, I have been forced now and then to make Digressions from my Subject, to clear some Doctrines necessary to be known which have not been Explained by others. For indeed the Data from which We argue in these Matters are by many too few. Dr. Cheyne, the Author of the New Theory of Fevers, has enumerated several Particulars in which the Theoretic Part of Medicine still wants Improvement. If these Deficiencies were made good, We might with more Ease Proceed in our Enquiries into Human Nature, and should soon Convince the World, that the most useful of Arts, if duly Cultivated, is more than meer Conjecture, or base Empiricism. As to the Authors I have made use of, who have Treated of Poisons, I have Quoted only those who Furnished me with Matter of Fact; For there are but few Originals; and very large Volumes on this Subject do many times contain little more than a Collection of Vulgar Errors. I had once Thought to have carried these Searches farther; in Particular, besides what is occasionally mention’d in the last Essay concerning Infection in acute Diseases, to have enquired into the Nature of Contagious and Hereditary Distempers. But the Humour of Scribling would not hold out; And some perhaps will say, ’Tis well enough it didn’t; For I am not Ignorant how Few I am like to Please; If it be hard to Think and Write Justly, ’tis harder yet to Bring Others to one’s own Taste; Nor shall I be at all Angry, if to Many I have afforded Matter of Satyr and Invective; Less Wit suffices for These than for the Discovery of Useful Truths. They who have no Smattering of Mathematical Knowledge, are incompetent Judges of what Service I have done towards the Improvement of the Theory, or Practice of Medicine, and Those who are acquainted with these Matters, will, it may be, think it something to Talk Intelligibly on such difficult and abstruse Points. I neither want Applause, nor fear Censure; and therefore be the Fate of These Papers what it will, as they were first Penn’d for my own Satisfaction, and Innocent Entertainment; so I am resolved They shall never Ingage me in the Trouble of Quarrels or Disputes. T HE C O N T E N T S. ESSAY I. Of the Viper. An Appendix containing Anatomical Observations, and an Ac​‐ count of some other Ve​no​mous An​i​mals. ESSAY II. Of the Tarantula and Mad Dog. ESSAY III. Of Poisonous Minerals and Plants. ESSAY IV. Of Opium. ESSAY V. Of Venomous Exhalations from the Earth, Poisonous Airs and Wa​ters. The E S S AY. I . O F T H E V I P E R . Viper has always been so Notorious for its Venom, that the most remote Antiquity made it an Emblem of what is Hurtful and Destructive. Nay, so terrible was the Nature of these Creatures, that they were very commonly thought to be sent as Executioners of Divine Vengeance upon Mankind for Enormous Crimes, which had escaped the Course of Common Justice. Thus Herodotus (1) and Ælian (2) do both take notice that Adders were sacred among the Ægyptians; that they affirmed of one sort of ’em particularly, that they were made to be Ministers of the Will of the Gods, by averting Evil from Good Men, and punishing the Bad. And Pausanias (3) observes of the Arabians, that they forbore to offer any Violence to the Vipers which were found near to the Balsam-Tree, as reputing ’em Holy. The Footsteps of which Superstition do still remain among these People to this very Day, for Veslingius (4) saw many of ’em take these Creatures into their Houses, feed ’em, and worship them as the Genii of the Place. The same odd Fancy obtains in the East-Indies, for the King of Calicut causes Cottages to be set up for Serpents to keep them from the Rain, and makes it Death to any that shall hurt one of ’em; thinking them to be Heavenly Spirits, because they can so suddenly Kill Men (5). A Remarkable Instance of such an Opinion as this we have in the History of St. Paul (6), whom the People of Malta when they saw the Viper leap upon his Hand, presently concluded to be a Murderer, and as readily made a God of him, when instead of having his Hand Inflamed, or falling down Dead, (one or other of which is usually the Effect of those Bites) he without any harm shook the Beast into the Fire. It being Obvious enough to imagine, that He must stand in a near Relation at least to the Gods themselves, who could thus Command the Messengers of their Vengeance, and Counterwork the Effects of such powerful Agents. And this, after the many Conjectures upon the Matter, seems to be the true Reason why Antiquity not only Represented the First Masters of Physick, Hermes, Æsculapius, Hippocrates, &c. in their Statues and Medals, with a Viper added to their Figure, but also Worshipped them under this Form, for Diseases in those Days, especially the most Violent, Plagues, Fevers, &c. were in like manner, as these Creatures, reputed the Commission’d Messengers of Divine Anger and Displeasure (7). They therefore who by their Art could Cure and Stop the Course of these, as they were supposed to do this by the particular Leave and Assistance of Heaven, so had Honours paid to Them accordingly, and this Representation was in the Nature of an Hieroglyphick Character; for as the Learned Spanhem observes, (8) the Viper was a Symbol or Emblem of Divine Power. Macrobius indeed gives us another account of this Custom, and that is from the Property which all Serpents have of casting their Exuviæ, or Upper-Skin, every Year, which makes ’em fit Emblems or Representations of Health; the Recovery of which from Sickness and Diseases may justly be looked upon as the beginning of a fresh Period of Life, and (as the throwing off the Senectus of these Creatures seems to be) the Renewing of Age (9). Whether one or the other of these Reasons be allow’d of, or both thought good, certain it is that such fond and superstitious Fancies concerning the Viper, together with the mistaken Opinion that few of its Parts were exempt from Poison, did not suffer the Ancients to make any Curious Enquiries into its Nature by Anatomy and Experiments, and this is the Cause of the many Errors they have delivered down to us in these Points, which by gradual Advances have since been rectified, and the inward Make, Properties, and Generation of this Animal, largely treated of; more especially M. Redi (10), Charas (11), and Dr. Tyson in his Dissection of the Rattle-Snake (12), which is a larger Species of a Viper, have taken Pains on this Subject, to whose Discoveries, what is yet wanting, we shall add at the End of this Essay. The Symptoms which follow upon the Bite of a Viper, when it fastens either one or both its greater Teeth in any Part of the Body, are an acute Pain in the Place Wounded, with a Swelling at first Red, but afterwards Livid, which by degrees spreads farther to the Neighbouring Parts with great Faintness, and a Quick, tho’ Low, and sometimes Interrupted Pulse, great Sickness at the Stomach, with Bilious, Convulsive Vomitings, Cold Sweats, and sometimes Pains about the Navel; and if the Cure be not speedy, Death it self, unless the Strength of Nature prove sufficient to overcome these Disorders; and tho’ it does, the Swelling still continues inflamed for some time; nay, in some Cases more considerably upon the abating of the other Symptoms, than at the beginning; and often from the small Wound runs a sanious Liquor, and little Pustules are raised about it; the colour of the whole Skin is changed Yellow, as if the Patient had the Jaundice. These Mischiefs, altho’ different Climates, Season of the Year more or less Hot, the greater or lesser Rage of the Viper, the Beast it self of a larger or smaller Size, and consequently able to communicate more or less Venom, and the like Circumstances, may variously heighten or abate ’em, yet do usually discover themselves much after the same manner in all; unless the Bite happen not to be accompanied with the Effusion of that Liquor, which is the main Instrument and Cause of this violent and shocking Disturbance. But before I proceed to enquire into the Nature and Manner of Acting of this Juice, it may be worth the while to take Notice, that this is not made on purpose to be deadly and destructive to Mankind ; but that the true Design of it is (tho’ Authors have not regarded it) to perform an Office and Service of so great Moment, to the Preservation of the Individual, that without it this Creature could not subsist. For Vipers live chiefly upon Lizzards, Frogs, Toads, Mice, Moles, and the like Animals, which they do not chew, but swallow down whole, and they lie in the Stomach; or if that be not big enough to receive them, partly in that, and partly in the Œsophagus, which is membranous and capable of great Distension, till by the Salival Juices of those Parts, together with the Help of the Fibres of the Stomach, and the Contraction of the Muscles of the Abdomen, they are gradually dissolved into a Fluid Substance, fit for the Nourishment of their Bodies, which is the Work of many Days; this is one Reason why these Creatures can live so long without taking any fresh Food, which I have known them to do Three or Four Months; as another is, that their Blood is a grosser and more viscid Fluid than that of most other Animals; so that there is but a very little expence of it by Transpiration, and consequently less need of Recruit; this not only Microscopes discover, but Reason teaches; because there is but very little Muscular Force in the Stomach to comminute the Food, and make a Chyle of fine Parts, and therefore the Blood must accordingly be of a Tough and Clammy Consistence. Besides, the Heart of a Viper has properly but one Ventricle, and the Circulation of the Blood is performed after the same Manner as it is in a Frog and Tortoise, in which not above one Third of it passes thro’ the Lungs; upon which Account its Comminution in them by the Air is proportionably lesser than in other Animals. Now such a manner of Feeding as this does necessarily require, that the Prey should upon the first Catching be immediately kill’d, otherwise it were by no means fit to be let into the Stomach; for we are not to think that the Force of this Part would be alone sufficient to destroy it, the Subtilty of a living Creature (besides the Consideration of the Weakness of the Fibres) being in a great Measure able to elude that, as indeed we do every Day find live Animals in the Ventricles of others; and therefore to do this is the proper Use both of the Teeth and their Poison; for which being designed and adapted, it is no wonder if the Viper, this same Way by which it destroys its Prey, proves sometimes mischievous to any other Creatures besides, when it happens to be enraged, or by any Provocation stirr’d up to bite. The Description of the Poisonous Fangs, their Make, Articulation and Motion, as also of the Glands that separate the Yellowish Liquor, and the Bags that contain it; I shall give, together with some Anatomical Observations, at the End of this Discourse. This Venomous Juice it self is of so inconsiderable a quantity, that it is no more than one good Drop that does the Execution; and for this reason Authors have contented themselves with Trials of the Bite upon several Animals, never Essaying to examine the Texture and Make of the Liquor it self; for which purpose I have oftentimes by holding a Viper advantageously, and inraging it till it struck out its Teeth, made it to bite upon somewhat solid, so as to void its Poison; which carefully putting upon a Glass Plate, I have with a Microscope, as nicely as I could, viewed its Parts and Composition. Upon the first Sight I could discover nothing but a Parcel of small Salts nimbly floating in the Liquor, but in a very short time the Appearance was changed, and these saline Particles were now shot out as it were into Crystals of an incredible Tenuity and Sharpness, with something like Knots here and there, from which they seemed to proceed, so that the whole Texture did in a manner represent a Spider’s Webb , tho’ infinitely Finer, and more Minute; and yet withal so rigid were these pellucid Spicula , or Darts, that they remained unaltered upon my Glass for several Months (13). I have made several Trials with this Juice in order to find out under what Tribe of Salts these Crystals are to be ranged; and not without some difficulty, by reason of the Minute Quantity of the Liquor, and the Hazard of Experiments of this Nature, have plainly seen that it does, as an Acid , turn the blue Tincture of Heliotropium to a Red Colour. I did not succeed so well in mixing it with Syrup of Violets, and yet it did really seem to induce in this a Reddish Hue; but I am very certain it did not at all change it to a Greenish Colour, as it would have done if any ways Alcalious. This may suffice in their own way of arguing, to convince those Gentlemen, who without the Assistance of any Experiments, meerly to serve an Hypothesis which they have too fondly taken up, have with great Assurance told the World, that the Viperine Venom is an Alcali, and consequently to be cured by Acid Remedies. But it is by far more easie to Spin out a false Notion into precarious Reasonings, than to make faithful Experiments, and fairly improve ’em by just and necessary Consequences. To proceed, this Discovery agrees very well with a Relation communicated by an Ingenious Person to Dr. Tyson , which does so much illustrate this Matter, that I shall transcribe it in his own Words, out of the before cited Philosophical Transactions; he says then, That being in the Indies, there came to him an Indian with several Sorts of Serpents, offering to shew him some Experiments about the Force of their Poison; having therefore first pulled out a large One, the Indian told him this would do no Harm; and making a Ligature on his Arm as in letting Blood, he exposed it naked to the Serpent, being first irritated to make him bite it; the Blood that came out of the Wound made by his Teeth, he gathered with his Finger, and laid it on his Thigh, till he had got near a Spoonful, after this he takes out another called Cobra de Capelo , which was lesser, and inlarges much upon the Greatness of his Poison; to shew an Instance of it, grasping it out about the Neck, he expresses some of the Liquor in the Bags of the Gums, about the Quantity of half a Grain, and this he puts to the coagulated Bleed on his Thigh, which immediately put it into a great Fermentation , and working like Barme, changed it into a Yellowish Liquor. This I say does well enough accord with what we have been advancing concerning the Nature of this Juice, for Mr. Boyle has long since proved by Experiments, that there is nothing of Acid in human Blood; and Dr. Pitcarn (14) has demonstrated, that the Acid Substances of Vegetables taken into the Stomach, are by the Action of this Part, the Lungs and Heart, when they come into the Blood-Vessels, turn’d to Alcalious; so that the Arterial Fluid must necessarily be considered as an Alcali; and therefore according to the known Principles of Chymistry, its mixture with such a Liquor as we have discovered the Viperine Sanies to be, will always exhibit some such appearance as this now related. But not to engage any farther in these sort of Controversies, we may perhaps from the foregoing Observations receive some Light in order to understand the Nature and Reason of all those Symptoms which attend the Bite of this Creature. For the pungent Salts of this Venom, when with Force thrown into the Wound, will not only as so many Stimuli, irritate and fret the sensile Membranes, whereupon there necessarily follows a greater Afflux than ordinary of the Animal Juices that way, (as is manifest from the Bellinian Doctrine, De Stimulis) so that the wounded Part must be Swelled, Inflamed, Livid, &c. but also these Spicula being mixt with the Blood, will so disjoin and disunite the Parts of it, that its Mixture must be quite alter’d; and from the various Cohæsion of its Globules will arise such different Degrees of Fluidity and Impulse towards the Parts, &c. from what this Liquor had before, that its very Nature will be changed, or in the common way of speaking, it will be truly and really Fermented . To understand aright how all this is done, it is necessary to hint somewhat concerning the Nature of Fluids in General, and those Alterations in them which we call Fermentations; for I shall retain this known Word, tho’ in the proper Sense in which ’tis commonly used, there can be no Fermenting of the Liquors in the Animal Body. And here I must refer to the Treatise of Bellini de Fermentis, who has with great Clearness shewn, that there is in all Fluids not only a simple Contact of their Parts, but also a nisus in Contactum, or Cohæsion , and this of a certain Degree or Force, and besides, of a particular Direction ; which is indeed, tho’ express’d in other words, the very same thing with the Attraction of the Particles one to another; This Mr. Newton has demonstrated to be the great Principle of Action in the Universe, has taught us the Laws of it in the greater Quantities and Collections of Matter; and he who rightly Studies his Philosophy will understand that the same obtains in the most Minute and Finest Corpuscles, which do unite into Bodies of different Solidity and Make, according to the Degree with which they do mutually attract each other, and to the Superficies, by which, when drawn, they do touch and adhere. To this if we add a Pression of the several Parts of the Fluid every way, and consider withal, that this Uniform Attraction of the Parts to one another must be variously changed by the different Attraction of Heterogeneous Bodies mixt with them, we have the great Principles of all Fluids, upon which their several Phænomena do depend. And hence it follows, that whatsoever Power is sufficient to make a Change in this Attraction, or Cohæsion of the Parts, makes an Alteration of the Nature of the Fluid; that is, as the Chymists express it, puts it into a Fermentation . And if any one shall think it necessary to enquire into the particular Manner of producing such an Effect, we may perhaps in so abstruse a Matter not improbably Conjecture thus, That our Blood consisting chiefly of Two Parts, a simple Lymph , and an infinite Number of small Globules, containing a very subtle and elastic Fluid, these acute Salts, when mingled with it, do prick those Globules, or Vesiculæ, and so let out their imprisoned active Substance, which expanding it self every way, must necessarily be the Instrument of this speedy Alteration and Change (15). From such an Hypothesis as this (and, it may be, not very easily from any other) we may account for many of the surprizing Phænomena in the Fermentations of Liquors; and as precarious as it seems, its Simplicity, and Plainness, and Agreement with the forementioned Doctrine, will, I believe, recommend it before any other to those who are not unacquainted with Geometrical Reasonings. But I wave these Considerations at present, and shall only add One Remark or Two with Relation to the purpose in Hand, and so proceed. In the first place then, we may from this Theory, learn, how it comes to pass that so small a Portion of Juice should infect so great a quantity of Liquor; for in order to do this, it is not necessary that the Venom should be at the very first mixt with all its Parts; but it is sufficient that it prick some of the Bladders, and the elastic Matter of these being let out, will be a nimble Vehicle to the acute Salts, and not only by its activity disperse them thro’ the Fluid, but restore to them their decreasing Force, and thus continue their Effects, till a great part of the Liquor undergoes at least, in some Degree, the like Alteration. And this will the more easily happen in the present Case, because the Force with which this Poison is thrown into the Blood, as appears from the Mechanism of the discharging Organs, is very great, and consequently its Effects will be proportionably violent, or the Mischief more large and diffused. The want of this may be one Reason why the Experiment of first making a Wound in the Flesh with any sharp Instrument, and then dropping in the Sanies, may not always succeed so well in killing Animals, as one would from the preceeding Doctrine be ready to expect. Tho’ if some amends be made for this Defect, by taking a greater quantity of the Juice, and carefully instilling it, It proves equally Fatal this way, as when immediately discharg’d from the Viper it self. Thus it might happen that those Trials of this kind, which were happily made by Sr Redi, might not however convince Mr Charas, in as much as there is oftentimes a great deal of difference in the Event of Experiments, when made with Purpose, and a Design that they should succeed, and when Timorously and Cautiously managed, lest they should unluckily overthrow a darling Hypothesis. The other Observation I shall draw from the foregoing Theory, is this, That it appears from hence what a vast variety there may be in the Fermentations even of one and the same Fluid; for these being no other than Changes made in the Cohæsion of the compounding Particles, are capable of as many Alterations as Motion in its Degrees and Directions can admit of, which are really Infinite. This I mention with regard to some of the following Essays, in which, if we ascribe many Symptoms seemingly very different, to a Ferment rais’d in the Blood, it may be consider’d, that the Nature of this Cause is such, as according to the several Properties of the Primum Agens, or Fermenting Power, to bear by far more Varieties than any one can be aware of. To return to the Viper; the Effects of such an Agitation of the Blood, as we have been describing, must not only be whatever are the Consequences of a disturbed Circulation , and irregular and interrupted Secretion of the Spirits, as low Pulse, Faintings, Sickness, Palpitation of the Heart, Convulsive Vomitings, Tremblings of the Body, &c. but also the Texture of this Fluid being thus broken, those Parts of it which are of the slowest Motion, and greatest Viscidity, will be easily separated from the others; such they are, which when united together do compound the Bile, and therefore these will tinge the Capillary Vessels, and fine Ducts in the Skin, with a Yellowish Colour; that is, will induce an Icterus, or Jaundice. For it is not only (if at all Primarily) from an Obstruction of the Biliary Canals that this Symptom does proceed, but also from any Cause whatsoever, which either destroys the Saline Part of the Bile, by the means of which its Oil is kept mixt with the Water of the Blood, or else increases the Oily and Sulphureous Part to that Degree, that tho’ it be duly impregnated with Salt, yet the Watery Part of the Blood, which can only take up a certain Proportion of it, being already Saturated , can receive no more; or lastly, does, by disuniting the compounding Particles of the Blood, alter that Intestine Motion and Agitation which is necessary to carry along thro’ the Vessels, together with the more volatile Parts, those which are more Clammy and Glutinous. For in all these Cases ’tis plain that the Bilious Corpuscles must be præcipitated upon those Parts of the Body where there is least Motion, that is, upon the extreme Superficies. And tho’ this Theory may perhaps appear extravagant, because new and uncommon, yet it will not, I believe, seem ill grounded or irrational to those who understand the Doctrine of the Mixture of Heterogene Fluids, and their Separation ; and who withal know, that the Vessels are rarely obstructed, unless it be from the fault of the Liquid they carry, and consequently that a Defect in the Bile it self must be (excepting some extraordinary Cases) antecedent to the Obstruction of the Biliary Ducts. In short, the different Cure of this Disease confirms these Notions; for an Icterus from the first Cause assign’d, which is generally owing to a sedentary Life, want of Exercise, &c. and attended with an extreme Costiveness and white Fæces, is cured by Volatile, Acrimonious, and Bitter Salts. From the Second produced oftentimes by drinking strong Liquors, Spirits, &c. and accompanied with a Diarrhœa , partly by Diluting and Temperating, partly by Stomachic and Strenghning Medicines. As the last Species of it (for the sake of which we have mention’d the other) is removed by such Antidotes as overcome and destroy the Venomous Ferment, corrupting the Blood, and breaking its Compages. But to have hinted these things may abundantly suffice for the present. We must however take Notice, That tho’ the main Alterations made by this Poison be in the Fluid of the Arteries, yet that That of the Nerves may hereby be considerably changed too; for This consisting, as well as the Blood of differing Parts, and being dispersed in small Tubes all over the Body, is not only very capable of various Degrees of Force, Impulse, &c. but Undulating continually towards the Brain, and being the chief Instrument of Motion and Action, may perhaps sometimes more immediately convey the Mischief to the sensile Membranes, and thus be the Cause of those violent Pains, Convulsions, Sickness, &c with which Those who are Bitten are presently seiz’d. Many are the Experiments I could relate to evince the Truth of this Reasoning concerning the Viperine Venom, which do entirely agree with those made by Sr Redi, whose Judgment and Sincerity in Observations of this Nature no Body ever called in Question, till Monsieur Charas having espous’d a Notion, that this Poison does not lie in the Yellow Liquor of the Gums, but in the enraged Spirits of the Viper, rais’d new Difficulties about the Success of some Trials made in France, endeavouring thereby to invalidate the Force and Authority of those made in Italy. I shall therefore, in order to put this Matter out of all doubt, mention Two or Three Experiments made by Dr. Areskine, when at Paris, that it may appear how defective those of Mr. Charas are, and that the Difference of the Climate does not (as some began to imagine (16)) make any considerable Alteration in the Effects of this Venom, or its manner of Killing. First then, having got a large Female Viper, he made it to Bite Six Pigeons, one after another; the First and Second that were bit, died within about half an Hour, one a little Time before the other; the third liv’d about two Hours; the Fourth seem’d to be very sick, but recovered; the Fifth and Sixth were no more hurt than if they had been prick’d with a Pin or Needle. Then he cut off the Head of a brisk Viper, and let it lie twenty four Hours, with the Fangs of which he wounded One Pigeon in the Breast, and another in the Thigh, which both expired as soon after, as if they had been biten by a living Viper. After this, having got a great many Vipers together, he made them bite upon a peice of Glass of a Cylindrical Figure, by this means preserving the Yellow Juice which they emitted, and slightly wounding two Pigeons, he first let the Bleeding be stopt, then put some of this Liquor into the Wounds, upon which both the Pigeons died about two Hours after. The same Ingenious Person tells me, that Monsieur du Verney made not only These, but also several other Experiments of the same Nature, in the Royal Acamy, with the like Success. These Proofs are so convincing and full, that no one, I think, can desire more; but they will receive yet a farther Confirmation from the Apparatus or Mechanism of the Organs, with admirable Nicety contrived for the Discharge of this Venom, of which more by and by. Nor is it any Objection against all This, that the Liquor is innocent and harmless in the Mouth or Stomach of any one, so as that it may be safely tasted or sucked out of the Wound, and swallowed; for, as we observ’d before, that many Acid Substances taken into the Stomach are by the Action of that Part turned to Alcalious, so there is no Question but these Saline Spicula are partly by the Muscular Force of the Fibres, partly by the Salival Juice, all broken and dissolved; or if any can pass into the Intestines, the Balsam of the Bile will be an Antidote for Them; the Reason of which will appear when we come to the Cure. In the mean time it may not be amiss to Remark, That even the Ancients seem to have known thus much concerning the Nature of this Poison; of this Galen gives us Testimony in severl Places; particularly in his Book de Temperamentis (17), where he takes notice, that nothing has the same Power upon the human Body outwardly as inwardly; Thus (says he) neither the Venom of the Viper, nor of the Asp nor frothy Spittle of the Mad Dog, are alike Mischievous when they fall upon the Skin, or enter into the Stomach, as when outwardly communicated by a Wound. The chief of the Latin Physicians (18), Celsus has elegantly express’d the Matter in few Words, when advising to Suck the Wound made by the Bite; he adds, Neq; Hercules Scientiam præcipuam habent hi qui Psilli nominantur, sed audaciam usu ipso confirmatam, nam Venenum Serpentis, ut quædam etiam Venatoria Venena, quibus Galli præcipuè utuntur, non gustu sed in vulnere nocent. And therefore brave Cato , when marching the Remains of Pompey’s Army thro’ Africa , very wisely told the Soldiers, almost choak’d with Thirst, yet afraid to drink of a Spring they came to, because full of Serpents (19), Noxia Serpentum est admisto sanguine Pestis, Morsu Virus habent, & Fatum Dente minantur, Pocula Morte carent―― In the like manner it was in those times also known, that the virulent Juice had the same bad Effects, when mixt with the Blood, by means of a common Wound, as when communicated by the Venomous Bite. This made Celsus (20) advise in sucking out the Poison, to take care there be no Ulcer in the Mouth; tho’ this Caution be rather slighted and ridiculed by Severinus (21), and others; who do hereby discover how little they understood of the Seat and Nature of this Poison. And Galen (22) mentioning the Story of Cleopatra , relates from other Authors, that she killed her self by pouring the Virus of an Asp into a Wound made in her Arm by her own Teeth . In short, it is upon this Foundation, that Pliny (23) assures us, the Scythians Poison’d their Arrows with the Sanies of Vipers mixt with human Blood; the way of doing it Aristotle (24) has at large related; and the Tartars are said to use the like Trick to this Day. After the same manner the Indians make use of the Venom of the Lizard, called Gecco ; this Creature they hang up by the Tail, and by Whipping exasperate till it discharge its Virus, in which they tinge their Darts; and a very slight Wound with these Weapons is speedy Death (25). It is worth the while in the next Place to consider the Cure of this Mischief, which without all doubt ought to be by such External Mannagement of the Wound as may immediately destroy the infused Venom. Mr. Boyle (26) experienced a hot Iron held as near the Place as the Patient could possibly endure it very effectual to this Purpose. But the same Method did not answer Expectation in the famous Case related by Monsieur Charas (27). An extraordinary Virtue against this and other venomous Bites is ascribed to the Snake-stones brought from the East-Indies, one of which is to be presently apply’d to the Part, and let stick till it drop off; these are said to be taken out of the Head of the Serpent called by the Portugueze, Cobra de Capelo; and to suck the Poison out of the Wound. Sr Redi (28) made Trials with several of them, but found no Service from any. Yet Baglivi (29) tells us of a terrible Bite of a Scorpion cured this way. Monsieur Charas (30) his Pigeons all died, tho’ these were immediately clapped on, and stuck close to the Wound: But Dr. Havers saw a good Effect of one upon a Dog, who tho’ severely bitten, suffered no Harm, nor any farther Mark of the Poison than a livid Circle round the Place. In plain Truth, as these celebrated Stones do not seem to be what it is pretended they are, but rather Factitious Bodies compounded, it may be, of Calcined Bones, and some Testaceous Matters mixt together; so by Reason of their spongy and porous Texture, they do very readily adhere to any moistened Part of the Flesh, and imbibe whatsoever humidity they meet with. This their Quality any one may experience by holding one of them to the Roof of his Mouth; and it is upon this Score, that when put into Water, Bubbles are raised by the Air in their Interstices, which some have too fondly thought to be the Effects of their throwing out the Venom they had sucked in. Their make being thus, some Part at least of the Poisonous Juice may easily be drawn out of the Wound by such an Application, and yet so much of it may sometimes happen to remain in the Flesh, as may make the Bite however to prove Mortal. And thus it fared with a Pigeon, to the Thigh of which, first bitten by a Viper, I applied one of the Stones; for tho’ it stuck fast to the Wound, and thus saved the Life for about four Hours; (whereas others usually died in about half an Hour) yet after this the Mortification of the Part prevailed to that Degree as to become fatal to the tender Creature. But our Viper-Catchers have a Remedy far beyond all these, in which They do place so great Confidence, as to be no more afraid of a Bite than of a common Puncture, immediately curing themselves by the Application of their Specifick .

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