Chapter VI: Part 6

The fact of accelerated, or retarded putrefaction, therefore, cannot be received with any confidence as a collateral indication of poisoning. _Dr. Carson_, however, in the trial of _Charles Angus_, adduced the circumstance of its absence, as a negative proof that the deceased had not been poisoned; and in the celebrated Scotch trial of _Patrick Ogilvy_, and _Catharine Nairne_,[197] the same fact was forcibly urged in their defence.

_Gaspard à Reies_,[198] and other writers, have maintained that the discovery of _living_ worms in the intestines of a person, suspected to have died from poison, ought to be received as a direct refutation of the charge. We are, however, not disposed to concur in such an opinion. With respect to the value of the indication supposed to be afforded by the circumstance of froth issuing from the mouth of the corpse, soon after death, _Mr. Hunter_ has given a very satisfactory opinion, and to which we must refer the reader, see _Appendix_, p. 273.

Q. IV. _How far the absence of poison, or the inability of the chemist to detect it, in the body, or in the fluids ejected from it, is to be received as a negative to an accusation of poisoning?_

We have already stated, that of all the proofs which can be adduced by the physician, in support of a charge of murder by poison, no one can be put in competition with that which arises from the discovery of the poisonous substance itself, in the stomach, or in the contents of the matter ejected by vomiting or purging. The law expects, therefore, that the professional witness should be prepared to state, that every experiment, calculated to detect the presence of poison, has been scrupulously and faithfully performed; and we may take this occasion to observe, that the circumstance of advanced putrefaction can rarely, in the present state of our chemical knowledge, be admitted as a satisfactory plea for not having proceeded to an anatomical inspection, as preliminary to chemical inquiry; and, as to the danger of such dissections, _Dr. Gordon Smith_ has very truly observed, “that much is placed to this account which belongs merely to disgust.” Had an examination of the body taken place in the case of _Ogilvy_ and _Nairne_, how many doubts would have been cleared away; indeed, this omission afforded the prisoners a strong ground of defence; they complained that the informer had intentionally prevented the dissection of the body, being conscious that the suspicions he had raised, and the project he had formed for their ruin, would, by such a measure, have been totally removed and defeated. To this it was answered, that when the informer (a younger brother of the deceased) arrived, he did insist on the body being opened and examined, as soon as a physician of eminence could be present, which the prisoners did not then oppose; but that when the physician arrived on the ensuing day, he declared the body to be in such a putrid state, that no certain conclusions could be drawn from outward appearances, nor even from a dissection of the body, which, besides, could not be performed with safety to the surgeon and attendants, and that he therefore thought proper to decline the investigation. Fortunately for the ends of justice, the circumstantial evidence of guilt was too strong to be affected by this culpable defect in the medical testimony, although it has been often asserted that the prisoners should have received the benefit of the omission by an acquittal. See _Donellan’s_ case in the _Appendix_, p. 243.

With respect to the mode of conducting a chemical analysis upon these occasions, we have reserved our directions, until we shall enter on the discussion of poisons individually. We have, however, in this place some remarks of a general nature to offer, to which we are desirous of drawing the attention of those, who, without much experience, may be called upon to conduct such investigations. In the first place, we are desirous of convincing him, that the processes which he must institute, for the detection of a mineral body, are by no means so elaborate and embarrassing, as a superficial view of the subject may lead him to conclude. During the progress of the present work the author has repeatedly felt the truth of the opinion which he is now expressing; for, like _Becher_, he has laid down his pen, and taken up his tests, and, by the most simple modes of manipulation, has satisfied his own mind of the extreme delicacy of the different processes which are recommended for the detection of a poisonous mineral; in short, it is very difficult to convince those whose chemical knowledge is wholly theoretical, with how little trouble, and with how much pleasure and profit, such experiments may be conducted. If such then be the perfect state at which our analytical knowledge has arrived, the reader may perhaps conclude, that _in every case of mineral poisoning the deleterious substance should be found, and that the inability of the chemist to detect its presence, should go far to negative the charge_. Such an inference, however, is neither correct, nor philosophical, for the poison may have been absorbed, or eliminated, during life, it may have undergone chemical changes, or it may have entered into combinations, by which its characters are masked, or wholly changed. To _Dr. Bostock_ the judicial physician is under many obligations, but there is no discovery for which he is more deeply indebted to him, than for that which has resulted from his satisfactory experiments, in elucidation of the present question. He has shewn, in the instance of _Corrosive Sublimate_,[199] that an animal may be suddenly killed by receiving a metallic poison into the stomach, and yet that the most delicate chemical re-agents may not be able to detect any portion of such poison, after death, in the contents of that viscus. _Dr. Henry_, in a letter to _Dr. Duncan_,[200] communicates the case of _Hannah Tomlinson_, aged twenty, who died, under the care of _Dr. Holme_, on the sixth day after a dose of _Corrosive Sublimate_. In this case, although an ounce of the mercurial salt had been swallowed, and the fluid ejected from the stomach was examined, only twelve hours afterwards, by _Drs. Henry_ and _Roget_, yet not the slightest trace of the poison could be detected! More recently we have received from the pen of _Mr. Alexander Murray_,[201] surgeon of Alford, some highly interesting cases of poisoning by Arsenic, and which are so illustrative of the present question, as well as several others that have fallen under consideration, that no apology can be necessary for introducing some account of them in this place. A family of the name of _Mitchell_, and which consisted of _William_, a robust man, aged 45, _James_, æt: 52, _Mary_, æt: 50, and _Helen_, æt: 48, breakfasted together on Sunday morning, (August 19, 1821) on porridge, consisting of milk, salt, and meal. _William_ partook largely, but _James_, who perceived “a sickening taste,” took less than common, while the sisters had their usual quantity. _William_ was seized with sickness shortly afterwards, about 10 _a. m._, on his way to church, and then with thirst and headache; and, on his return home, between three and four in the afternoon, he was seized with vomiting, which recurred often during the next four or five days, especially on his attempting to quench his thirst. In the early part of the week, he was heard to complain of pain in his stomach, eyes, throat, breast, and arms; he was observed to void his urine frequently; and about this time, he pointed out to one of his sisters a hollow[202] between his breast and belly, into which according to her expression, “she could have laid her arm.”

His illness had scarcely at any time confined him to bed. On the evening of Friday, the 24th of August, he rode six miles, for the purpose of consulting _Mr. Murray_, the surgeon, and reporter of the cases; on Wednesday the 22d he had taken a dose of Epsom salts which operated, and at the time _Mr. Murray_ first saw him he complained of the following symptoms:—pain and heat in the region of the stomach and lower part of the chest; occasional uneasiness in the abdomen, and sometimes ineffectual efforts to go to stool; thirst; difficulty of breathing; heat and uneasiness of throat, with hoarseness; soreness of eyes, which had the common appearance of inflammation; shifting pains in his extremities, particularly the arms, which had not their usual strength; great restlessness; anxious expression of countenance; pulse frequent, 100-110, not strong.

A blister was applied over the stomach and lower part of the chest, and he took an opiate at bed time. On the following day, (Saturday 25th) _Mr. Murray_ visited him at his own house, and found him nearly as before, except that his countenance more strongly exhibited a disturbed and anxious expression, and the redness of the eyes, and the hoarseness were increased. _Mr. Murray_ also observed small roundish white accuminated prominences, on the palate and uvula, apparently as if the membrane covering the palate bones and _velum pendulum_, was detached at the parts by a whitish liquid. This day he took an ounce of castor oil, which operated in the afternoon, his illness was not observed to change during the evening, and he retired at about eight o’clock to rest. At a little past two in the morning, he rose in search of water to drink, and on returning to bed he was heard to utter a deep groan; after which he lay motionless and quiet, and very soon was found to have expired. The surgeon who saw the body, about 10 _a. m._, states that “_many bluish spots were observed on the inferior extremities_.” _James_, _Mary_, and _Helen Mitchell_ were attacked the same forenoon with their brother _William_, and with nearly similar symptoms; they were all, however, fortunate enough to recover, although a considerable period elapsed before their usual strength returned, and in all of them a numbness of the arms, or legs, occurred, together with a loss of muscular power.

The body of _William Mitchell_ was, owing to particular circumstances, not opened until the 29th of August, (3 days 8 hours after death) when the following appearances presented themselves. “The face had a natural, composed appearance; and the rigidity of the body did not appear to be different from what is common. The right ear, and corresponding side of the face, as well as the scalp, exhibited a deep clay-blue colour. On the chest and belly, several spots and streaks, some green, others blue, were observed; and the back, upon which the body lay, was from head to foot of a livid colour; while several roundish spots, of a still deeper hue, gave to the shoulders and neck a mottled appearance. The penis was much swollen and red. The scrotum also was enlarged, and of a dark blue colour.

Upon opening the abdomen, the smell was not unusually offensive, and its contents did not appear to have undergone alteration after death, but several ounces of a highly-coloured liquid were found in the cavity. The surface of the jejunum and ilium presented many purple spots, some of which were several inches in circumference. The peritoneal surface of the stomach, in a tract which extended from the cardia, and occupied, for some distance downwards, the whole circumference of that viscus, except the small curvature, was of a clear, dark red colour; and through this space dark lines, apparently veins, were observed to ramify. This appearance, perhaps, from 20 to 30 square inches in extent, was strongly marked in contrast with the natural state of the inferior extremity and small curvature. The substance connecting the stomach to the spleen, was, as well as a small part of the transverse colon, of a red colour. The spleen was gorged with blood; the liver healthy. The duodenum, from a small distance below the pylorus, almost to its inferior extremity, and round nearly the whole intestine, was of a very dark purple colour. Upon opening the stomach, the internal surface of that part where the outward appearance, already described, existed, was found of a bright red colour, and over this lighter dots were thickly scattered[203], making such an appearance as might be produced by a red colour being dashed from a painter’s pencil, upon a somewhat darker _ground_.

The internal coats of the duodenum were very dark coloured, with a slightly reddish hue, pulpy, thickened, and easily separated from the peritoneal covering, while in one roundish spot, of the size of a crown piece, the villous and muscular coats were entirely wanting. Red patches were observed on the inner surface of the jejunum and ilium, the shape, size, and situation of which were the same as those of the appearances already noted as occurring on the outside of these intestines. The stomach and duodenum contained about a quart of a brown, semi-opaque, thickish liquid; the jejunum and ilium were empty, and coated with a yellow viscid matter. The lungs and heart were quite healthy; but in the cavity of the thorax were ten ounces of a reddish turbid liquid, and about half that quantity in the pericardium. The pharynx was of an unusually red colour. The whole of the brain was healthy, and of firm consistence.”

_Mr. Murray_ concludes by stating that no part of the salt and milk used on the sunday morning, was to be found after he visited the family, and that although the remainder of the meal, and also the contents of _William Mitchell’s_ stomach and duodenum were examined by _Drs. Henderson_ and _Fraser_, of Aberdeen, as well as by _Mr. Craigie_, surgeon, who assisted in the dissection, and _Mr. Alexander Murray_, yet, “_no poisonous ingredient was detected in these substances_.”

The pathological and anatomical facts were, however, in themselves, so striking and satisfactory, that not the slightest doubt can exist as to the cause of the sufferings and death of the deceased; while, as _Mr. Murray_ very justly states, the high probability, arising from the separate symptoms of each individual, is strengthened almost to certainty, by the simultaneous occurrence of these in a whole family of four persons; while no similar disease, indeed no epidemic of any kind, prevailed at that time.

We have only to add that the brother-in-law of this family was, in October, 1821, tried before the Judiciary Court at Aberdeen, for administering poison to his four relations; when the testimony given by the medical witnesses induced the judge and jury to consider the abstract act of poisoning proved. The accused afterwards confessed his guilt, and that he perpetrated the crime by means of _Arsenic_, put among the salt on the sunday morning on which the family were taken ill.

The public, and the profession, are greatly indebted to _Mr. Alexander Murray_ for the details of this instructive case; and the patient attention and judgment with which he conducted the investigation, deserve the highest commendation, and afford an example which we sincerely hope future practitioners will endeavour to follow.

Q. V. _What degree of information can be derived from administering the contents of the stomach of a person supposed to have been poisoned, to dogs, or other animals?_

It has from time immemorial been generally believed, that no proof of poisoning is more satisfactory than that which is furnished by the effects produced upon dogs, by their swallowing the contents of the stomach of persons who are supposed to have died from poison. Writers on Forensic medicine have, however, adduced several objections to the validity of such a test; some of which are undoubtedly worthy of consideration, while others are the deductions of a theory which receives no support from experience. In the first place it has been stated, that substances poisonous to man, will not always occasion deleterious effects upon animals[204]; this, to a certain extent, is undoubtedly true; some of the _Ruminantia_ appear to be less sensible to the operation of narcotic plants, than carnivorous animals. _Aloes_ are injurious to dogs and foxes. Oxen are said to eat the _Philandria Palustris_, which is pernicious to horses; but we are very much inclined to believe that a poison sufficiently powerful to destroy the life of a man, would if administered in the same state of concentration, destroy that also of an inferior animal. It is in smaller doses only that the difference in the action of such bodies upon various animals becomes evident and appreciable. This opinion is confirmed by numerous experiments. _Mr. John Hunter_, in his evidence[205] on the trial of _Donellan_, in answer to the question, whether any certain conclusion can be drawn respecting the poisonous operation of a substance upon man, from its effects upon an animal of the brute creation, replied, “_As far as my experience goes, which is not a very confined one, because I have poisoned some thousands of animals, they are very nearly the same; opium, for instance, will poison a dog similar to a man; arsenic will have very near the same effect upon a dog, as it would have, I take it for granted, upon a man; I know something of the effects of them, and I believe their operations will be nearly similar._” If any farther confirmation of this opinion were required, how extensively and satisfactorily has it been afforded by the late experiments of _M. Orfila_.[206] _Mr. Hunter_ also, on the memorable trial above mentioned, explained a source of fallacy which attends such experiments upon animals; he is asked “whether there are not many things which kill animals almost instantaneously, that will have no detrimental or noxious effect upon a human subject, such, for instance, as spirits?” He replies that a great deal depends upon the manner of conducting the experiment, and that by forcing an animal to drink, the liquor often passes into the lungs. See _Appendix_, _p._ 272. _Orfila_, in his valuable work on poisons, instituted a series of experiments upon this subject, with the intention of determining the value of an experiment so generally accredited; from which he is led to conclude, 1st. That the practitioner should never attempt by force to make an animal swallow the suspected substance, nor should he put it into his food; for by such a proceeding he would not only run the hazard of losing the greatest part of it, because the animal would reject it, but the food with which it is combined might exert upon it some chemical action, or so envelope it as to protect the coats of the stomach from its contact; besides which it would, says he, happen, at least six times in ten, that a part of it would flow through the larynx into the lungs, and the animal will die of Asphyxia. 2d. The best method that can be employed, consists in detaching the œsophagus, perforating it with a small hole, introducing into it a glass funnel, and pouring the liquid into the stomach; that being done, the œsophagus is to be tied below the opening. It would, observes _M. Orfila_, be imprudent to prefer to this method, the use of an elastic gum tube adapted to a syringe, for many bite the tube, pierce it with holes, and the fluid then flows out of the mouth; besides which, syringes of tin might decompose certain poisonous fluids. The obvious objection to such a mode of administration is anticipated by this laborious experimenter with much ingenuity. It may be asserted, says he, that the animal perished from the operation of tying the œsophagus, and not from the action of the poison thus introduced into the stomach, but such an objection has no foundation in truth, for either the suspected substance is in quantity sufficient to destroy the animal, or it is not; in the first case death will take place during the first forty-eight hours, and will be preceded by symptoms more or less severe, a phenomenon never observed in the simple ligature of the œsophagus; in the second case, the experiment will not be more conclusive, than if the œsophagus had not been tied: and the author asserts, that the operation of tying the œsophagus would not, of itself, produce during the first forty-eight hours any other symptom than a slight dejection, and that consequently all other morbid phenomena that may be observed, upon such trials, ought to be attributed to the poisonous substance. To all this we reply, that we believe, in the hands of _Orfila_ who has made a thousand experiments, that such results may be satisfactory, but we feel no hesitation in declaring, that we should not place the smallest reliance upon such an experiment when conducted by a person unaccustomed to the operations of experimental physiology. If there be no other mode of employing an animal as a test for poison, but by tying his œsophagus, we must, in a judicial point of view, reject it altogether.

But there still remains another source of fallacy connected with these experiments, to which considerable importance has been attached. It has been said that the acrid humours ejected from the stomach of a person labouring under a _spontaneous_ disease, may kill an animal. _Morgagni_[207] relates a very remarkable instance, in illustration of this fact. A child having died of a fever was opened, when a quantity of green bile was found in the stomach, which changed the colour of the scalpel to violet; having dipped the point of the knife into this bile, two pigeons were wounded with it, and they soon died in convulsions. The bile was then mixed with some bread, and given to a cock, which also died in the same manner. From this general view of the subject before us, the forensic physician will be enabled to appreciate its just value, and to apply the indications it may furnish, in each particular case, without the risk of error. In some instances such experiments may prove nothing, in others they may afford only equivocal results, but which may add something to the general weight of circumstantial evidence; while others, again, may furnish proofs so unquestionable, as to leave no doubt upon the subject; such was the case in the instance of _Michael Whiting_[208], who was convicted of administering corrosive sublimate to his brothers-in-law, when it appeared in evidence that a portion of the poisoned dumpling was given to a sow, who in consequence became sick, and remained ill for several days.

We have now disposed of the several questions connected with the subject of poisoning, which must be regarded, in their forensic relations, as being of the highest importance. In considering the subjects, generally, there must necessarily remain doubts, many of which will be considerably diminished, or entirely removed, upon their application to particular cases; still, however, the nature of medical evidence upon such occasions must be frequently regarded as only sustaining high probabilities, and the professional witness may exclaim with _Hoffman_[209] “_Ardua sane provincia ei imponitur cui determinandæ ejusmodi quæstiones exhibentur._”

ON THE CLASSIFICATION OF POISONS.

Poisonous substances have been very differently arranged by different authors, each appearing to have adopted a classification best suited to promote the particular views and objects of his own pursuit; thus, the botanist and chemist, engaged in the examination of the physical characters by which poisons may be individually distinguished and identified, have very judiciously erected their system upon the basis of natural history. The pathologist, whose leading object is the investigation of the morbid effects which follow the administration of these agents, with equal propriety and justice prefers a classification deduced from a generalization of the symptoms they are found to occasion; while the physiologist, who seeks to ascertain through what organs, and by what mechanism they destroy life, may be reasonably expected to arrange the different poisons under divisions corresponding with the results of so interesting an inquiry.

To meet the comprehensive views of the forensic toxicologist, an arrangement would seem to be required, that should at once embrace the several objects which we have just enumerated; for the data from which the proof of poisoning is to be inferred, are, as we have often stated, highly complicated in their relations. No such classification, however, can be accomplished, and we are therefore compelled to select one which may approach the nearest to our imaginary fabric. That which was proposed by _Fodéré_,[210] and adopted, with some trivial alteration in the order of succession of the classes, by _Orfila_, in his celebrated system of toxicology, although it has many defects and some errors, nevertheless merits the preference of the forensic physician; its basis is strictly pathological, and yet it distributes the different poisons, with some few and unimportant exceptions, in an order corresponding with that of their natural history.

The first two classes, for instance, present us with substances of a mineral origin; the third and fourth, with those which are principally of a vegetable nature; and the sixth, with objects chiefly belonging to the animal kingdom. The importance of acknowledging a division, which has a reference to the three great kingdoms of Nature, is perhaps greater than the reader may anticipate; for in enumerating the various experiments to be instituted for the detection of poisons, we are, by such an arrangement, enabled to bring together a connected series of processes, nearly allied to, intimately connected with, and in some respects, mutually dependant upon each other.

The following is the arrangement of _Fodéré_ as modified by _Orfila_: viz. Cl. I, _Corrosive_, or _Escharotic poisons_. Cl. II, _Astringent poisons_. Cl. III, _Acrid_ or _Rubefacient poisons_. Cl. IV, _Narcotic_ or _Stupefying poisons_. Cl. V, _Narcotico-Acrid poisons_. And Cl. VI, _Septic_ or _Putrefying poisons_.

Class I. CORROSIVE or ESCHAROTIC POISONS. Such as corrode and burn the textures to which they are applied. When internally administered they give origin to the following symptoms: violent pain accompanied with a sense of heat and burning in the stomach, and throughout the whole extent of the alimentary canal; frequent vomitings, often sanguineous, and alternating with bloody diarrhœa, with or without tenesmus; the pulse hard, small, frequent, and at length imperceptible; an icy coldness of the body; cold sweats; a great anxiety and oppression at the præcordia; and hiccup. Sometimes the heat of the skin is intense, the thirst inextinguishable, and the unhappy patient is tormented with Dysuria and Ischuria, violent cramps in the extremities, and horrid convulsions, which are relieved only by death. Such are the general symptoms by which this species of poisoning is characterised; the rapidity with which the symptoms terminate their course, will depend upon the violence of the dose, and the particular species of poison which has produced them; there are, moreover, other symptoms which will be more conveniently described, when we come to speak of the effects of corrosive poisons individually. In this class are ranked the following substances. METALS. I. Arsenic—1. _Arsenious Acid_, or white oxide of Arsenic. 2. _Arsenites_, or combinations of that acid with _salifiable bases_. 3. _Arsenic Acid._ 4. _Arseniates_, or combination of the preceding acid with the bases. 5. _Sulphurets of Arsenic_, or _Orpiment_ and _Realgar_. II. Mercury—1. _Corrosive Sublimate of Mercury_, or _Oxy-muriate of Mercury_. 2. _Red Oxide of Mercury._ 3. _Red Precipitate_, or _Nitric Oxide of Mercury_. 4. Other preparations of Mercury. III. Antimony—1. _Tartarized Antimony_, or _Tartar Emetic_. 2. _Oxide_ _of Antimony._ 3. _Antimonial Wine._ 4. _Muriate of Antimony_, or _Butter of Antimony_. IV. Copper—1. _Blue Vitriol_, or _Sulphate of Copper_. 2. _Verdegris._ 3. _Oxide of Copper._ 4. Other preparations of Copper. V. Tin—1. _Muriate of Tin._ VI. Zinc—1. _Sulphate of Zinc_, or _White Vitriol_. 2. _Oxide of Zinc._ VII. Silver—1. _Nitrate of Silver_, or _Lunar Caustic_. The Concentrated Acids—1. _Sulphuric._ 2. _Muriatic._ 3. _Nitric._ 4. _Phosphoric_, &c. Hot Liquids—1. _Boiling water._ 2. _Melted Lead._ The Caustic Alkalies—1. _Potass._ 2. _Soda._ 3. _Ammonia._ The Caustic Alkaline Earths—1. _Lime._ 2. _Baryta._ 3. _Muriate_, and _Carbonate of Baryta_. Cantharides. Phosphorus.

Class II. ASTRINGENT POISONS. They occasion a remarkable and unrelenting constriction of the great intestines, especially the colon, so as to resist the operation of the most powerful cathartic remedies. Violent cholics ensue, and partial paralysis; in the end if the dose be sufficiently large, or if small doses have been frequently repeated, they will excite inflammation of the alimentary canal, but it is not succeeded by that disorganization which generally characterises the operation of poisons, belonging to the preceding division. We rank under the present class only the preparations of Lead, viz. 1, _Acetate of Lead_, or _Sugar of Lead_; 2, _Oxides of Lead_; _Red Lead_; _Litharge_; 3, Various Saturnine impregnations.

Class III. ACRID, or RUBEFACIENT POISONS. These poisons are known by their producing an acrid taste, more or less pungent and bitter; a burning heat, and considerable dryness in the mouth and fauces; and a constriction, more or less painful, in the throat. Acute pains are, after a short interval, experienced in the stomach and bowels, which are quickly followed by copious vomiting and purging, and which continue, with the most painful efforts, long after the alimentary canal has been completely evacuated. A few hours after, phenomena are observed which indicate a lesion of the nervous system, such as vertigo, dilated pupils, dejection, insensibility, laborious respiration, and death. The lesions of texture, occasioned by the action of _Acrid_ poisons, have the greatest analogy to those produced by _Corrosive_ poisons; in fact, says _M. Orfila_, “we do not hesitate to declare, that there exists a perfect identity between the alterations of the digestive canal produced by the poisons of these two classes, when introduced into the stomach.” The substances included under this class belong, for the most part, to the vegetable kingdom, such as _Scammony_, _Camboge_, _Black_ and _White Hellebore_, _Bryony_, _Euphorbium_, Seeds of the _Ricinus_, _Iatropa Curcas_ (Indian nut), _Croton Tiglium_, _Squill_, _Aconite_, &c. &c.

Class IV. NARCOTIC, or STUPEFYING POISONS. Such as occasion stupor, drowsiness, paralysis, or apoplexy, and convulsions. They do not produce any change in the structure of parts to which they are applied. _M. Orfila_ has satisfactorily ascertained that no alteration can be discovered, on dissection, in the digestive canal of persons who have swallowed any one of the poisonous substances of this class.

Class V. NARCOTICO-ACRID POISONS. This division, as its name implies, is intended to receive such substances as produce the united effects of those belonging to the two preceding classes, acting for instance at the same time, as narcotics and rubefacients. Amongst the articles of this class the following may be enumerated, _Belladonna_, _Stramonium_, _Tobacco_, _Foxglove_, _Hemlock_, _Nux Vomica_, _Camphor_, _Cocculus Indicus_, certain _Mushrooms_, _Alcohol_, &c. &c.

Class VI. SEPTIC and PUTREFYING POISONS. By this term are included those poisons which, according to _Orfila_, “occasion a general debility, dissolution of the humours, and syncope, but which do not, in general, alter the intellectual faculties.” The articles of this class belong almost entirely to the animal kingdom, with the exception perhaps of a few gaseous compounds, and the _Spurred Rye_, or _Ergot_, viz. _venomous animals_; _animals whose fluids have been depraved by antecedent disease_; _the poison of fishes_; _substances in a state of putridity_; _Spurred Rye_, or _Ergot_.

Such is the classification which, for reasons already stated, it is our intention to adopt on the present occasion. We shall, however, in an additional chapter, under the title of “_Aërial Poisons_,” treat of those substances which are exclusively capable of acting upon the body through the medium of the atmosphere, or which require to be in a state of vapour, or gas, to ensure their operation.

With regard to the classification of _Fodéré_ and _Orfila_, we must here observe that we follow it only conventionally, and that, while we acknowledge it as being very convenient for the consideration of poisons, in reference to their forensic relations, yet we must not be considered as insensible to its many defects and fallacies. In the first place, it has little or no reference to the enlarged views of the modern physiologist, respecting the “_modus operandi_” of poisons; nor indeed is its construction susceptible of such modifications and improvements, as can ever render its degree of perfection progressive with the advancement of science. In the next place, the classes are in many particulars ill-defined, and indistinctly, if not erroneously, divided. How questionable, for instance, are the boundaries which separate _Corrosive_ from _Acrid_ poisons? even the respective species of each class are, in many instances, less allied to each other than the great divisions to which they are subordinate. As an exemplification of this fact we have only to compare the physiological actions of _Arsenic_ and _Corrosive Sublimate_; the former of these substances occasions death by being absorbed, and thus acting as a vital agent, the latter, by its local action as a caustic on the textures with which it comes in contact. In the same manner, if we examine the individual actions of the different species composing the class of “_Acrid_” poisons, we shall find the same want of uniformity; thus the _Spurge-flax_, and the _Jatropa Curcas_ act by occasioning a local inflammation, while the _Hellebore_, being rapidly absorbed, exerts a fatal action on the nervous system, and produces only a very slight inflammation. The class of Narcotic poisons is more absolute in its definition, and more uniform in its physiological affinities, and therefore less objectionable, than the divisions to which we have just alluded; but the propriety of the term “_Narcotico-Acrid_” may be very reasonably questioned;[211] even _Orfila_ expresses his doubts upon the subject, “because the narcotic or sedative effects only follow the previous excitement.” Some of the poisons, under this last mentioned class, are rapidly absorbed, and act, through the medium of the circulation, on the nervous system, without producing any local inflammation; whilst others, again, merely act upon the extremities of the nerves, with which they come in contact, and without being absorbed, occasion death by a species of sympathetic action.

These few objections, and many more might be adduced, are sufficient to demonstrate the imperfection of the classification under consideration, and which would render it wholly unavailable to the pathologist who must adopt his treatment according to the physiological action of each poison. The author has accordingly, in his “Pharmacologia”[212] ventured to propose an arrangement, in conformity with such views; and the following sketch of it may perhaps form a useful introduction to the general observations which it will be hereafter necessary to offer upon the “_modus operandi_” of poisons.

A CLASSIFICATION OF THE DIFFERENT MODES BY WHICH POISONS PRODUCE THEIR
EFFECTS.

† This mark denotes that the substance, against which it is placed, may also act by being absorbed.

‡ Signifies that the article has also a local action.

I. BY ACTING THROUGH THE MEDIUM OF THE NERVES, WITHOUT BEING ABSORBED,
AND WITHOUT EXCITING ANY LOCAL INFLAMMATION.

a. _By which the functions of the nervous system are destroyed._

Acrid.

Aconite.
Jatropa Curcas.

Narcotico-Acrid.

Alcohol.
Oil of Tobacco.

Narcotic.

Essential Oil of Almonds.†
Camphor.†
Opium†?

b. _By rendering the heart insensible to the stimulus of the blood._

Infusion of Tobacco.
_Upas Antiar._

II. BY ENTERING THE CIRCULATION, AND ACTING THROUGH THAT MEDIUM WITH
DIFFERENT DEGREES OF FORCE, ON THE HEART, BRAIN, AND ALIMENTARY
CANAL.

Corrosive.

Arsenic.
Emetic Tartar.
Muriate of Baryta.

Acrid.

Hellebore.
Savine.
Meadow Saffron.
Squill.

Narcotic.

Opium.‡
Lettuce.
Henbane.
Prussic acid.

Narcotico-Acrid.

Deadly Nightshade.‡
Hemlock.
Camphor.‡
Cocculus Indicus.

III. BY A LOCAL ACTION ON THE MUCOUS MEMBRANE OF THE STOMACH, EXCITING
A HIGH DEGREE OF INFLAMMATION.

Corrosive.

Corrosive Sublimate.†
Verdegris.
Muriate and
Oxide of Tin.
Sulphate of Zinc.
Nitrate of Silver.
Acids.
Alkalies.
Cantharides.†

Acrid.

Bryony.
Elaterium.†
Colocynth.†
Camboge.
Euphorbium.
Hedge Hyssop.
Croton Tiglium.
Ranunculi.

The preceding classification of poisons will not only furnish the practitioner with a general theorem for the administration of antidotes, but it will suggest the different modes and forms of administration of which each particular substance is susceptible; it will shew, that certain poisons may occasion death without coming into contact with any part of the alimentary canal, and that others will produce little or no effect, however extensively they may be applied to an external surface. The first class comprehends such poisons as operate, through the medium of the nerves, upon the organs immediately subservient to life; in the application of such agents it is obvious that they cannot require to be introduced into the stomach, they may convey their destructive influence by an application to any part duly supplied with nerves, and whose extremities are exposed to their action; although at the same time, it may be observed that, in general, poisons of this kind act most powerfully when internally administered, owing to the extensive sympathetic relations of this central organ over every function of the living body. The second class consists of poisons that are incapable of producing any effect, except through the medium of the circulation; whence we shall be enabled to explain and appreciate the various circumstances which may accelerate or retard their operation. Poisons of this class may be applied externally to abraded parts, or even to surfaces covered with cuticle, provided their absorption be promoted by friction; and it may be here observed, that the function of absorption is not performed with the same force in every tissue; as a general proposition it may be said to be energetic in proportion to the number of lymphatics and veins, although the late experiments of _M. Majendie_ have shewn how greatly it is influenced by the state of the circulation.[213] If these poisons be administered internally, they find their way into the circulating current either through the branches of the thoracic duct, or those of the _venæ portarum_; when, as if by a species of election, each substance very frequently expends its venom upon some one particular system of organs. Many of the substances arranged under this second division, have moreover a local effect upon the structure with which they first come in contact; it is thus with _Colocynth_, and some other bodies; while on the contrary, several of those poisons which are distinguished for their _local action_, are subsequently absorbed, and are thus as it were enabled to ensure their work of destruction by a double mode of operation. We shall receive ample evidence of this truth, as we proceed in the history of particular poisons. The third class comprises such agents as inflict their vengeance upon the mucous membrane of the stomach, by actual contact, and destroy, by exciting local inflammation.

_MINERAL POISONS._

Under this head is included the greater proportion of those substances which are employed as the instruments of crime; for they are generally of easy access, require but little preparation, and are so destructive in small doses, and, at the same time, so little disgusting in flavour, as to furnish the assassin with the sure and secret means of destruction. Fortunately, however, for the ends of justice, such agents are pre-eminently the objects of successful analysis. In treating of the history of the individual substances derived from this kingdom, we shall consider, 1st. their _external characters_, such as form, colour, odour, taste, specific gravity; 2d. their _chemical composition, and habitudes_; 3d. _the tests by which their presence may be recognised_; _4th. the symptoms which they occasion_; _5th. their physiological action_; _6th. their different modes and forms of application_; _7th. the lesions of structure they occasion_; _8th. the phenomena presented on dissection_.

Cl. 1. CORROSIVE POISONS.

ARSENIC.

The greek word Αρσενικον was employed by _Dioscorides_, and other writers of that period, to denote a particular mineral of a reddish colour, which _Aristotle_ had already described by the name of σανδαρακη,[214] and his disciple _Theophrastus_, by that of αρρενικον. It was employed by the ancients both as a pigment and as a medicine, and appears to have been a compound of Sulphur, and a peculiar metal, to which the name of _Arsenic_ is now exclusively applied. At what period this metal was first discovered seems very doubtful; and although a process for obtaining it is described in the Pharmacopœia of _Schroeder_, published in 1649, yet its peculiar nature was examined, for the first time by _Brandt_, in 1733.

The metal, Arsenic, is distinguished by the following properties, viz.

It has a bluish-grey colour, not unlike that of steel, and a considerable lustre; its texture is grained, and sometimes scaly; its hardness not very considerable, but its fragility is so great that it falls to pieces under a moderate blow of the hammer, and admits of being easily reduced to a very fine powder; according to _Bergman_ its specific gravity is 8·31. When cold, it emits no sensible odour, but if heated, it yields a strong _alliaceous_, or garlic-like smell, which is to be considered as the most characteristic of its properties. Its point of fusion is unknown, for it is the most volatile of all the metals, and sublimes, before it melts, at the temperature of 540° Fah., and if the process be conducted slowly in close vessels, the metallic sublimate will assume a _tetrahedral_[215] form of crystallization; if the air be admitted, and the temperature still farther raised, it will burn with an obscure bluish flame.

Arsenic is extremely susceptible of oxidation, and, by mere exposure to the air, shortly loses its metallic lustre; and yet it may be kept under the surface of _cold_ water, for any length of time without exhibiting the signs of oxidation, or solution; a covering of this fluid, or of alcohol, is therefore considered as affording the best means of preserving the metal in a state of integrity.

Arsenic is capable of combining with two proportions of oxygen, and of forming two definite compounds, which we shall hereafter consider under the title of _Arsenious_ and _Arsenic_ acids. The substance described by some authors as the _black oxide_ of this metal would seem to be an indefinite mixture of the metal itself, and the arsenious acid.

Arsenic does not appear to possess any deleterious properties, but it is almost impossible to reduce the metal to powder, so as to adapt it for exhibition without its becoming oxidized. _M. Renault_ therefore, in order to decide the question, had recourse to its alloys; and he found that _Mispickel_ (an alloy of Arsenic and Iron), when given to the extent even of two drachms, scarcely produced any effect; a result which very satisfactorily accords with the conclusion drawn by _Bayen_, in his work on Tin, and which proves that the arsenic contained in that metal, need not excite the least alarm, since it exists in a metallic state. We have upon another occasion[216] observed, that the vapours characterised by an alliaceous odour are probably less noxious than the arsenical fumes which are inodorous; and that the little injury experienced by workmen who solder silver filligree with an arsenical alloy, may probably depend upon the deoxidized state of its fumes.

ARSENIOUS ACID, or WHITE OXIDE OF ARSENIC.

This is justly considered as the most fatal of all mineral poisons, and is the one more frequently selected than any other, as the instrument of assassination and suicide; while its numerous applications in medicine and the arts, by making it an article of general and indiscriminate sale, have rendered it an accidental as well as criminal source of suffering and death.

It is seldom prepared by the chemist, since it exists in a native state, and is moreover procured abundantly and economically, during the extraction of the other metals from their ores.[217] In the commercial world the substance is still known by the name of _White Arsenic_; and continues to be expressed in popular language, by the simple term _Arsenic_.

It generally occurs in the form of white compact masses, opaque on their exterior surface; transparent, and presenting a vitrified aspect in the interior. Its taste is acrid and corrosive, but not to a degree corresponding with its virulence. _Specific gravity_ 3·7. When reduced to powder it bears a strong resemblance to refined sugar, for which it has sometimes been fatally mistaken, and with which it has been often mingled for criminal purposes. At the temperature of 383° _Fah._ it is volatilized, and is capable of crystallizing in tetrahedrons with truncated angles, or rather in octohedrons; by a strong heat, in close vessels, it is vitrified and becomes pellucid, and acquires the specific gravity 5·000[218]; but when exposed to the air, it shortly returns to its former appearance. _In the state of vapour it is quite inodorous_, although the contrary is positively asserted in several chemical works of high authority, and it is stated to be characterised by a smell like that of garlic; the fact is, that the _alliaceous or garlic-like smell is wholly confined to metallic arsenic in a state of vapour_; and whenever the arsenious acid seems to yield such an odour, we may very confidently conclude that its decomposition has taken place, and that it has been reduced to its _metallic_ state. Such a reduction will generally happen when it is projected upon ignited charcoal, or when heated in contact with those metallic bodies which readily unite with oxygen, such as _Antimony_, _Zinc_, &c. It is stated by _Orfila_ and other writers, that if it be projected upon heated copper the alliaceous odour is evolved. This assertion is undoubtedly true, but the fact requires to be explained with more precision, or we may fall into an important error respecting it. The author has shewn by several experiments, already published in his _Pharmacologia_,[219] that the phenomenon takes place only when the copper is in a state of ignition, at which temperature its affinity for oxygen enables it to reduce the arsenious acid, and consequently to develope the metallic odour. We have ascertained by repeated experiments that if a few grains of arsenious acid be heated on a plate of copper, by means of a spirit lamp or the blow-pipe, no odour is perceptible; for, in this case, the whole of the acid will be dissipated before the copper can acquire a temperature sufficiently exalted to deoxidize, and reduce it. If the arsenious acid be heated on a plate of zinc, the smell will not be evolved until the latter metal is in the state of fusion. If, instead of the foregoing surfaces, we employ in our experiments those of gold, silver, or platina, no alliaceous smell whatever is produced, at any temperature, provided every source of fallacy be carefully avoided; but it deserves particular notice, that the author has found the flame of the spirit lamp to be in itself, capable of decomposing the arsenious acid, in consequence, it is presumed, of the operation of its hydrogen;[220] a fact which is very likely to betray the experimenter, as in the first instance it did the author, into a belief that the arsenious acid does actually yield the odour in question.

The term Arsenious _acid_ was first bestowed upon this substance by _Fourcroy_, since it was found to possess many of the essential habitudes of an acid; as for instance, that of combining with the pure alkalies to saturation. It dissolves in water; but, according to _Klaproth_, although it requires for its solution 400 parts of that fluid, at the temperature of 60° _Fah._ it requires not more than 13, at 212°; and it moreover appears that if 100 parts of water be boiled on the arsenious acid, and suffered to cool, it will retain 3 grains in solution, and deposit the remainder in crystals. This fact shews the great importance of employing boiling water in every chemical examination of substances supposed to contain arsenic. It proves also that a fatal dose of the poisonous mineral may be very easily administered in any watery vehicle, a fact which was denied on the trial of _Ogilvy_ and _Nairne_[221] by _Dr. James Scott_, who deposed that “Arsenic would not dissolve in warm water, but almost instantly subside to the bottom of the vessel,” although, at the same time, he acknowledged that “if it were put into tea with milk and sugar, and stirred about, it _might_ be suspended long enough to kill those who should drink the potion.” It is soluble in alcohol, and in fixed oils, the former taking up two per cent. By the addition of an alkali, an _arsenite_ of great solubility will result, and a solution of extreme virulence may be thus effected. With _lime-water_ arsenious acid produces a white precipitate of _arsenite of lime_, but which is soluble in an excess of the acid. With _magnesia_ it also forms a very soluble, and extremely active, _arsenite_.

_Symptoms of Poisoning by the Arsenious Acid._

_Hahnemann_, in his work on Arsenic, proposes a classification of its effects founded on their relative duration and violence, and which it is our intention to adopt on the present occasion, without any other alteration than that of reversing the order of the classes.

Poisoning by Arsenic may accordingly be considered as admitting of three degrees of intensity, viz. 1st. Where the case, although attended with dangerous symptoms, does not terminate fatally. 2d. Where death does not follow until after a lapse of twenty-four hours. 3d. Where death takes place within twenty-four hours after the exhibition of the poison.

1. _Symptoms of the first and lowest degree._ In the slighter cases in which the operation of arsenic is recorded as producing poisonous effects, the symptoms were, uneasiness of the præcordia; cholics; thickness, redness, and stiffness of the palpebræ; soreness of the gums; ptyalism; itching over the surface of the body, sometimes attended with a slight eruption; restlessness; cough; head-ache; strangury, and _ardor urinæ_. Where the dose of poison has been somewhat greater, although still inadequate to the destruction of life, violent vomiting is commonly the first symptom, preceded in some instances with a sense of heat and dryness in the fauces; in such cases where the vomiting has very shortly succeeded the ingestion of the Arsenic, and the stomach has at the same time been filled with food, the patient may owe his escape to the poison being discharged before it had time to act. _Morgagni_ relates a case of poisoning at an Italian feast, where the dessert was intentionally sprinkled with Arsenic instead of flour; those who had previously eaten but little speedily perished, but those who had eaten heartily were saved by vomiting. Although in this degree of poisoning the life of the patient may be spared, yet a variety of _consecutive_ symptoms may continue to harrass him for a longer or shorter period, such as indigestion, debility, partial paralysis, and epilepsy. The history[222] of the cases of _Mr. Turner_ and his family, of Chancery lane, for the poisoning of whom _Eliza Fenning_ was executed, will afford a striking illustration of this fact. The hair of the head has also been observed, in some cases, to fall off. _Dr. Male_ is also of opinion that the long protracted and injudicious use of this mineral, as a medicine, will induce exostosis and caries of the bones.

2. _Symptoms of the second degree._ In this case where the patient lives two or three days, or perhaps longer, as in the case of _William Mitchell_ above described (p. 190), the earliest symptoms are heat and thirst, or vomiting, and inexpressible uneasiness and anxiety, the former of which is less frequently observed than the two latter; purging, or sometimes a repeated but ineffectual desire to go to stool; wandering pains; quick, but feeble pulse; head-ache; distended and painful abdomen; priapism; towards the close of the scene the patient often becomes more tranquil and is inclined to sleep, although, in some instances, the pains, attended with convulsions, continue to the latest moments. In general, death takes place suddenly. In cases where the effects of the poison are not immediately fatal, we must necessarily expect the occurrence of many phenomena, indicative of the re-action of the system, and which will be better illustrated by a reference to the history of individual cases, such for instance, as those of _William Mitchell_, (p. 190) and _Mr. Blandy_, (_Appendix_) than by any general description which can be given in this place. It is also worthy remark that in such cases, from the length of time, there will necessarily occur a greater opportunity for the co-operation of other contingent causes, whether they be connected with previously existing diseases, or the action of remedies; and the intelligent practitioner will not neglect to appreciate their influence in modifying the character of each particular case. There are besides symptoms highly characteristic when they do arise, but which are of comparatively rare occurrence, such as the ulcerated condition of the fundament, as in the case of _Mr. Blandy_, and the inflamed eyes and state of the mucous membranes, in that of _William Mitchell_.