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.
3. Symptoms of the third and highest degree. Soon after a large dose of Arsenic has been swallowed, an austere taste, and a sense of heat and constriction of the pharynx and œsophagus are perceived; in a short period excruciating pains in the stomach and bowels, accompanied with vomiting of the most violent character, the matter voided being generally of a brown colour, and not unfrequently mixed with blood; with these symptoms are conjoined an inexpressible anxiety about the præcordia, and frequent faintings; the stomach at the same time acquires such a high degree of irritability, as to reject the mildest fluids. The alvine discharges now become frequent and painful, and consist of dark and extremely fœtid matter, frequently mixed with blood. The thirst is unquenchable, and the heat of the surface becomes extreme. The pulse is small, frequent, and irregular; palpitations of the heart, violent cramps in the legs, sometimes a painful strangury and bloody micturition ensue. The powers of life begin to fail, respiration becomes laborious, cold sweats break out, hiccup occurs, the countenance assumes a singular character of anxiety and distress, a livid circle appears around the eyes, the pulse is imperceptible, the body swells and sometimes becomes covered with a species of miliary eruption, or with dark purple spots. In some cases convulsions ensue, but delirium, or loss of reason, is very rarely the consequence of this species of poisoning, and the unfortunate sufferer is conscious until a few moments before the termination of his existence. Such are the general symptoms, but it is rare to see them all united in the same case; sometimes the greater part of them are absent. M. Chaussier reports the case of a robust middle aged man, who swallowed a quantity of arsenious acid in large lumps, and died without discovering any other symptom than slight syncope; other cases are related where only vomiting and purging[[223]] have been observed, and the symptoms have been mistaken for those of cholera spontanea.
The practitioner is therefore not to withhold his belief in a case of poisoning, on account of the absence of several of those symptoms which are enumerated in systematic works on Toxicology.
It is only by the study of individual cases, that he can learn to appreciate the just value of those pathognomonic combinations which afford the least exceptionable evidence upon such occasions.
The different modes of Poisoning by Arsenious Acid.
It has been proved by numerous experiments that the life of an animal may be destroyed with equal certainty by arsenious acid, whether it be internally administered, or externally applied to abraded surfaces, sores, or bleeding wounds; and it has been, moreover, shewn, that in either instance the symptoms will be analogous, except in the latter case they will often be more rapid in their course.
Lionardo di Capoa relates the case of a child killed by the violent vomiting and purging arising from a slight wound made in the head by a comb, wet with oil in which arsenic had been infused for the purpose of killing vermin; and we have numerous instances on record, where the application of arsenical cerates and ointments has been followed by violent and dangerous symptoms. We also learn from the different historians of the Plague of London, that the arsenical amulets which were worn, as preservatives, on that occasion, were sometimes attended with deleterious consequences; Crato[[224]] observed an ulcer of the breast produced by them. Verzascha, violent pains and syncope. Diemerbroeck,[[225]] and Dr. Hodges,[[226]] death itself. Amongst the foreign authors who have related cases of poisoning by the external application of arsenic we may mention Desgranges,[[227]] who records the history of a chambermaid, poisoned by having rubbed her head with an arsenical ointment for the purpose of destroying vermin; and Roux,[[228]] who confessed to have killed a girl of eighteen by an application of the “Pâte Arsenicale” to a cancerous breast. M. Renault has also given us the results of his experiments upon Arsenic when applied externally to dogs; when the skin was sound, it excited a pustular eruption without inflammation; but, when the skin was broken, more serious effects followed, both general and local, and in some cases death.[[229]]. In an experiment performed by Mr. Hunter, and Mr. Home, in which arsenic was applied to a wound in a dog, the animal died in twenty-four hours, and the stomach was found to be considerably inflamed. Mr. Brodie repeated the experiment several times, always with the precaution of tying a bandage, to prevent the animal licking the wound; the results were uniform; the stomach was, in every case, not only more violently, but more rapidly, inflamed, than when the poison had been internally administered, and it even preceded any inflammatory appearance of the wound. In the Journal de Medecine, the following case is related of a woman who was killed by her husband having insinuated powdered arsenic into the vagina,[[230]] at the moment of enjoying the conjugal rites. “A woman at Leneux, departement de l’Ourthe, aged forty, having died after a short illness, attended with considerable tumefaction of the genital parts, uterine hemorrhage, vomiting, and purging, the body was inspected by order of the mayor, when the surgeons reported that they found the vulva in a state of gangrene, the abdomen much distended with air, and the intestines inflamed and gangrenous. The culprit was arrested, convicted, and executed.” In the Acts of the Society of Copenhagen, a similar crime stands recorded, and which was also committed by a peasant; in this latter case, although some small pieces of arsenic were found within the vagina, yet some doubts arose respecting the possibility of such a species of poisoning, and the magistrates accordingly consulted the College of Medicine of Copenhagen, who decided the question in the affirmative, having first instituted a series of experiments upon horses.
Death may also be produced by the introduction of arsenic into the rectum; it is said that Sir Thomas Overbury, after the failure of the various poisons[[231]] that were administered to him, was at last despatched by an arsenical glyster.
With respect to the quantity of arsenic required for the production of such effects it is difficult to offer a decided opinion, as its operation must in every case be liable to contingency; but a very few grains are in general amply sufficient.
Physiological action of Arsenious Acid.
It had long been supposed that arsenic occasioned death by inflaming the stomach; but Mr. Brodie[[232]] has very satisfactorily proved, that its influence arises from its being absorbed, and that it must be regarded as a vital rather than as a chemical agent, and as having a constitutional, not a local mode of operation.
In the first place, he has in many instances found the inflammation of the stomach so slight,[[233]] that on a superficial examination it might have been easily overlooked; and in most of his experiments with arsenic, death took place in too short a period to be considered as the mere effect of inflammation. In the next place we have already shewn that in whatever manner the poison is applied, whether externally to a wound, or internally, to the alimentary canal, the same inflammatory appearance will be visible in the stomach; a fact which can only be explained by admitting that the poison is absorbed, and that it acts upon these organs through the medium of the circulation; it acts at the same time upon the brain, and heart, but with different degrees of force in different cases; so that it is sometimes difficult to ascertain which of these organs is the first to fail in its functions. According then to these experiments and observations, inflammation of the alimentary canal is not to be considered as the general cause of death in poisoning by arsenic; and yet cases will occur, where the local affection may prove fatal, the animal having survived the effects produced on the organs more immediately subservient to life, as the brain and heart. Mr. Henry Earle communicated to Mr. Brodie a case highly illustrative of this fact, which occurred in St. Bartholomew’s hospital; a woman had taken arsenic, and having recovered from the alarming symptoms which first occurred, died at the end of four or five days, when upon dissection, there appeared extensive ulcerations of the stomach and bowels. This then was evidently a case of “Consecutive” poisoning.
The dissertation of Dr. Jaeger, to which we have before alluded, contains the result of a very extensive series of experiments, in illustration of the physiological action of the arsenic. He diligently examined its effects upon all classes of organized beings, as well of the vegetable as of the animal kingdoms. The general conclusions which he has drawn from his experiments on vegetables are, that arsenic is in most cases a rapidly destructive poison to them, with the exception perhaps of a few of the simplest forms of existence;[[234]] and that their death was induced by means of the gradual absorption and distribution of the poison by the vessels and cellular membrane, so that the parts died in succession, as the particles of the poison reached them. Dr. Jaegar also found that arsenic was a quick and destructive poison to animals, and that death was preceded, in every instance, from the infusory animalcula up to man, by inordinate motions; and that the secretion was most remarkably increased from the mucous membranes. His experiments also proved that arsenic exerted the most powerful effects, when it was injected into the veins, or applied to a bleeding wound; next, when it was introduced into the stomach; but less so, when injected into the large intestines, which have fewer absorbing vessels.[[235]]
Organic Lesions, discovered on Dissection.
The examination of the bodies of persons poisoned by arsenic, must not be expected to furnish constant and uniform results, since they will be found to vary very considerably in different cases. As we have already considered the value of accelerated and retarded putrefaction, as an indication of poisoning, we shall at once proceed to the description of the morbid phenomena which are presented by the internal organs on dissection. The stomach and intestines are the parts in which we may expect to find the most decided marks of the ravages from arsenic. The former viscus will be found more or less inflamed; in some instances, the dusky redness will appear in patches, interspersed with points and streaks of a brighter hue; the villous coat of the stomach will be almost always softened, and, as if macerated, can be easily rubbed off in pieces with the fingers from the coats beneath; actual ulceration and sloughing are, according to the observations of Mr. Brodie, never found unless where death is late in taking place, in which case extensive ulceration of all the coats, amounting to actual perforation, may be expected to happen. This statement agrees with the observation of Ruysch, who says that where there had been sufficient time, he found the stomach ulcerated in those who had died from the effects of arsenic, but that if death supervened earlier, he only discovered bloody points, distant from each other, throughout the viscus. On the subject of sloughs upon such occasions, our enlightened author remarks, that anatomists have often been betrayed into a fallacy respecting their true nature; on opening the stomach of a dog which had taken a large quantity of arsenic, Mr. Brodie observed a dark brown spot about an inch in diameter, having all the appearance of a slough; on a closer examination, however, it appeared that this spot was no other than a very thin layer of coagulated blood, of a dark colour, and adhering very firmly to the surface of the mucous membrane, and having a few particles of arsenic entangled in it. He states that he has at several times observed a similar appearance but occupying a less extent of surface; and he informs us that, in the Hunterian museum, there is a human stomach, which was preserved for the sake of exhibiting what was considered a slough, produced by the action of arsenic; but that, on examining the preparation carefully, the dark coloured spot was discovered to be simply a layer of coagulated blood, similar to that before described. Dr. Baillie and Dr. Yelloly have found the stomach thickened in several parts, as if by coaguable lymph, and in one case the thickening of the coats was the only alteration of structure observable; and M. Renault relates a case, where the arsenic was taken in large pieces, which produced no other effect than slight syncope on the approach of death; and that, upon opening the body, the arsenic was found in the state it was swallowed, but there was neither inflammation nor erosion of the stomach. Where the arsenic has been swallowed in substance, it will be generally found attached to the membrane of the stomach by a peculiar glairy fluid; if the poison should have been administered in solution, the same organic lesions will be discovered, but the presence of the arsenic in the stomach can scarcely be expected, although the contents of the viscus, as well as all the matter ejected from the body before death, must be carefully examined by a chemical process to be hereafter described. The duodenum, like the stomach, generally affords evidence of the same inflamed and disorganized condition; and the whole track of the intestinal canal will be found more or less affected, according to the quantity of arsenic that has been administered, the period of time which has elapsed before death, and other circumstances which have been already enumerated as capable of modifying the action of this destructive substance. It however deserves notice that in many cases the rectum appears to be more affected than the other intestines; Dr. Male[[236]] states, that he has frequently found it abraded and ulcerated, and even more inflamed than the stomach itself; Mr. Brodie likewise observed, in his physiological experiments upon this substance, that the inflammation produced by it was greatest in the stomach and the rectum. Dr. Baillie has recorded several instances where a mortification of the rectum followed as an effect of this poison; and in the case of Mr. Blandy, detailed in the Appendix, p. 237, Dr. Addington stated, that the extremity of the rectum was extremely painful, and surrounded by excoriations and ulcers.
Mr. Brodie has stated, in the paper to which we have so often alluded, that the organic lesions occasioned by arsenic are confined to the stomach and intestines, and that he never found any appearance of inflammation in the pharynx or œsophagus. This statement, however, is at variance with a great weight of authority; we have ourselves witnessed cases in which dissection has demonstrated extensive inflammation in these parts; indeed it would appear, that this poison acts more particularly on the mucous membranes; and it is reasonable therefore to conclude, that those with which it comes in actual contact will not escape its virulence. The serous membranes which receive less blood, and more lymphatics, are necessarily less affected by it.
In the case of William Mitchell, as related at page [188], the patient complained of soreness of the eyes, heat and uneasiness in the mouth and throat; and the surgeon observed the membrane on the palate and uvula to be detached; so in that, again, of Mr. Blandy, Dr. Addington found on inspection that “his tongue was swelled, and his throat inflamed and excoriated; his lips, especially the upper one, dry and rough, and having angry pimples on them; the inside of his nostrils in the same condition, and his eyes a little blood shot.” (Append. l. c.). In the celebrated Scotch case of Oglivy and Nairne (see page [184]) Peter Meik, surgeon of Alyth, deposed, that, upon inspecting the body four or five days afterwards, he found “the tongue swelled beyond its natural size, and cleaving to the roof of the mouth, which he had never observed after a natural death.” Many more instances might be adduced to shew that the fauces, pharynx, and œsophagus are very frequently inflamed and excoriated by the ingestion of arsenic. Mortification of the pudenda[[237]] has been said to be an effect peculiar to the action of arsenic; certain it is that in males, priapism is sometimes a symptom of this poison, and the penis is found swollen and red after death, as was observed in the case of William Mitchell (p. [190]). The scrotum was also enlarged and of a dark colour. We have been long aware that persons exposed to the fumes of arsenic, or accustomed to handle any of its preparations, have been liable to a peculiar affection of these parts, but we have generally explained the fact by supposing that the poison had in such cases, been locally applied to them. The author has been lately informed by his friend Mr. Parkes, that several persons in his establishment were thus attacked, during the time they were engaged in preparing an arsenical solution, as a dye for the calico printers; and we have stated on another occasion,[[238]] that the smelters and workmen engaged in the copper works, and tin burning houses of Cornwall, are occasionally affected with a cancerous disease in the scrotum, somewhat similar to that which infests chimney sweepers. It is also singular that Stahl, in describing the putrescent tendency in the bodies of those who die from this poison, mentions in particular the gangrenous appearances of the parts of generation. The other organs of the body do not exhibit any particular appearances, which ought to be regarded as characteristic of death by arsenic; we must necessarily expect to find the traces of morbid action, especially where life has been unusually protracted; and the serous effusions found in the body of William Mitchell, are to be referred to such a cause.
Mr. Brodie has stated that, in animals killed by arsenic, the blood is usually found fluid in the heart and vessels after death; this agrees with the observation of Ruysch, who says that he never found the blood coagulated in the human body, after death occasioned by this poison; as well as with that of Dr. Jaeger, who describes the cavities of the heart, especially of the right side, to be, upon these occasions, turgid with blood, but that coagula are very seldom found in them.
A question, of a very considerable importance in a forensic point of view, has arisen with respect to the means, by which we may distinguish whether arsenic, found in the body, had been introduced into the digestive canal during life, or after death. In general, this fact is placed beyond suspicion by the testimony of those to whose care the body had been confided, previous to dissection. But cases have occurred where a poisonous substance has been introduced into the rectum of a dead body, with the diabolical intention of accusing an innocent person of having been the perpetrator of the poisoning. We are not aware of any English case of this kind, but M. Orfila states that in the proceedings of the Criminal Court of Stockholm such a case stands recorded. Fortunately there would not be much difficulty in detecting the crime; for were the arsenic applied to the rectum after death, the change of structure would not extend beyond the part in actual contact with it, but would be distinctly separated from the rest of the intestine by a well defined line of demarcation, which can never happen where the arsenic has acted during life; for, in this latter case, the transition from the diseased to the healthy structure will be gradual, and the limits of each imperceptible.
Before we conclude our observations upon the organic lesions occasioned by arsenic, we may caution the anatomist not to confound the red or violet colour which characterises inflammation, with that which has been occasionally found to arise from the ingestion of certain coloured drinks. The following case related by Foderé, and cited by Orfila, may serve to illustrate this subject. “A private person of Châlons sur-Marne, who was in a state of convalescence from a disease under which he had laboured, took a slight purgative, and died very shortly afterwards. He was believed to have been poisoned through some error in the medicine, and in order to be assured of this, the body was opened. The œsophagus and stomach were found to be red, and in certain places livid, as if in a state of gangrene. These appearances at first induced a belief that the deceased had died from poison; but M. Varnier, a physician of Châlons, concluded from the appearances, that death was the consequence of the disease, and that the apparent convalescence was only an insidious respite. It became therefore necessary to give some account of the state of the œsophagus and stomach; and having learnt that the deceased was in the habit of using a strong infusion of red poppies, the idea immediately struck him that the extraordinary colour of these organs might possibly depend on this infusion. In order to determine the validity of this explanation, he caused a dog to swallow, several times, a similar infusion; when upon opening its body, he discovered that the corresponding parts of this animal had assumed the same colour as had been observed in the stomach of the deceased above-mentioned, and, moreover, that this violet red colour was so firmly fixed that it resisted the action of repeated washings.” Tincture of Cardamoms will also be liable to occasion a coloured appearance in the stomach, as described in Mr. Stanley’s case of the death of a woman by a dose of opium.[[239]]
Of the Chemical Processes, by which the presence of Arsenious Acid may be detected.
This poison may either be submitted to the judicial physician for examination, in its solid form, or in that of solution; and in this latter state it may be mixed with various alimentary substances, whose presence will necessarily embarrass the inexperienced operator, and multiply the apparent difficulties of his task. It becomes our duty, therefore, upon this occasion, to enter very fully and minutely into the history of the various processes, which have been proposed for the solution of the important problem under consideration; to appreciate the relative value of each, and to point out the sources of fallacy and failure, to which they are severally exposed.
Such a review of the subject would, moreover, appear to be essentially necessary at the present period, since the evidence, lately delivered on an extraordinary trial,[[240]] has, to a certain extent, very unjustly shaken the public confidence in the tests of chemistry. We shall therefore proceed to consider the processes which are calculated to lead to the detection of Arsenic, in relation to the different circumstances under which it may be presented for investigation, viz. 1, In a solid form; 2, In the simple state of solution; and 3, In the state of combination with various alimentary substances.
1. The Arsenic is in a solid form. This is the most simple case which can occur, and the experiments by which its presence is to be demonstrated, will constitute the basis of the inquiry, which we shall be hereafter called upon to institute, for the detection of the same substance under other circumstances of mixture and combination.
The order of succession to be observed in the different experiments which we are about to describe, must, in a great measure, be regulated by the quantity of the material to be submitted to examination. Should it be small, it will be prudent to reserve the process of metallization, by which a considerable loss must necessarily arise, until we have submitted it to the various re-agents which are calculated to afford indications of its nature. If, on the contrary, the quantity of the substance exceed two or three grains, it will be adviseable to proceed in its examination by the following processes, reserving a portion for future analysis.
A. By its reduction to a metallic state. Mix a portion of the suspected substance in powder, with three times its weight of black flux[[241]]; put the mixture into a thin glass tube, about eight inches in length, and a quarter of an inch in diameter, and which is hermetically sealed[[242]] at one end. Should any of the powder adhere to the sides of the tube it must be carefully brushed off with a feather, so that the inner surface of its upper part may be perfectly clean and dry. The closed end of the tube, by way of security, may be thinly coated with a mixture of pipe-clay and sand[[243]]; but this operation is not absolutely necessary. The open extremity of the tube is to be loosely plugged with a piece of paper. The coated end must now be submitted to the action of heat, by placing it in a chaffing dish of red hot coals, for ten minutes, or a quarter of an hour; when, if our supposition respecting the nature of the substance has been correct, metallic arsenic will sublime, and be found lining the upper part of the tube with a brilliant metallic crust. The glass tube, when cold, may be separated from its sealed end by the action of a file, which will enable us to collect and examine the metallic sublimate. If a portion of this brilliant matter be laid on heated iron, it will indicate its nature by exhaling in dense fumes, having a powerful smell of garlic. Another portion should be reserved for future experiments.
This method of detecting the presence of Arsenious acid has been considered the most decisive, and indeed the only unexceptionable one, but of this we shall speak hereafter; at present we have only to observe, that it is very far from being a minute test, for Dr. Bostock[[244]] confesses that where less than three-fourths of a grain were used, he could not say that the metallic crust was clearly perceptible; and Dr. Black[[245]] appears to have considered that one grain was the smallest quantity which could be distinctly recognised by such a process.
Chemists were formerly[[246]] in the habit of at once projecting any substance, supposed to be Arsenic, on some burning body, in order to develope the alliaceous odour; we have accidentally stumbled upon an instance of this kind, in the fourth volume of the London Medical and Physical Journal, which may serve as an illustration; it is a case communicated by F. Thackeray, Esq. of a child poisoned by arsenic, in which the author says, “the inner surface of the stomach was very red, and was studded throughout with a white powder, which when exposed to the flame of a candle, yielded fumes, and a garlic odour was emitted, proving it was arsenic; of which there can be no doubt, as the girl afterwards confessed that she had given arsenic to the infant.”
After the facts we have offered with respect to the alliaceous odour of arsenical fumes, it is only necessary to state, in this place, that such a test, when conducted in the manner just related, must be considered as extremely equivocal.
Another method of identifying “White Arsenic,” by metallization, is to form at the moment of its reduction, an alloy with copper, which may be easily effected in the following manner: Mix the suspected powder with black flux, as in the former experiment, and place the mixture between two polished plates of copper; bind them tightly together by iron wire, and expose them to a low red heat; if the included substance contain arsenic, a silvery white stain will be left on the surface of the copper, which is an alloy of the two metals. In this, as in the former experiment, the presence of an alkali in the flux is essential, since it forms immediately an arsenite of potass, and thereby fixes the arsenious acid, and prevents it from being volatilized before the temperature is sufficiently high to enable the charcoal to decompose it; we therefore differ with Dr. Bostock, when he states that powdered charcoal may be substituted for the black flux.
The property of whitening copper is regarded as a very satisfactory test of the presence of arsenic; but Dr. Bostock has pointed out some circumstances attending it, which we shall here enumerate for the instruction and satisfaction of the less experienced operator. “It may be necessary,” says he, “in the first place, to describe the phenomena that take place when copper is heated according to the process that is described above, but without the addition of the arsenic. Two copper disks, of nearly an inch and a half in diameter, scoured bright with sand, had one grain of powdered charcoal, made into a paste with oil, placed between them; they were bound together with an iron wire, and then kept red hot for ten minutes. When they were withdrawn from the fire, the metal was found to have lost its former appearance, and to have acquired the dull white colour of lead or zinc; the insides of the disks were found to present the same whitish appearance, except on the spot where the charcoal was placed, a small part of which still remained unconsumed. As the disks cooled the whitish matter which covered them began to separate, and fly off with some force, in the form of small scales, leaving a clean surface of the proper copper colour. The charcoal was rubbed off, and the surface below it was found smooth and polished; it had acquired a light colour, resembling that of brass; and, near the centre, there was a small spot, which approached to a steel grey. This appearance still continued, after it had been rubbed with fine sand. The above description,” concludes Dr. Bostock, “will probably impress the Society[[247]] with the same idea, that, I confess, it gave to myself, that if I had performed this experiment upon a substance, which had been suspected to contain arsenic, and I had not been aware of the appearance that I was to meet with, I should have conceived that I had detected its presence. Upon repeating the process, in precisely a similar manner, except that one grain of arsenic was added to the charcoal, the oxidation of the copper took place as before, and a small part of the charcoal remained unconsumed; but upon rubbing it, the white stain was perfectly visible. However, when these disks were compared with those in which the former experiment had been made, the difference between them seemed more in degree than in kind; so that I should not choose to decide upon the presence of arsenic, as indicated by this test, unless the result were more obvious than we can ever expect to find it, where the quantity of arsenic is so small. It may be proper to observe, that copper, whitened in this manner by arsenic, is very subject to tarnish; in three days I could with difficulty distinguish which of the disks had been employed in these two experiments.”
In connection with the different modes of identifying arsenic by metallization, we may relate a test lately proposed by Mr. A. Thomson, which, as a collateral proof, merits some attention. “Into any solution, in which arsenic may be suspected, stir a moderate quantity of charcoal powder; allow it to settle; then pour off the clear supernatant liquor, or filter the mixture; and when the powder which remains on the filter is dry, sprinkle some of it on a red hot poker; if the solution contain arsenic, the odour of garlic will be rendered sensible. This effect becomes more obvious if a few grains of dry sub-carbonate of potass be added to the dried charcoal powder.”[[248]]
If, instead of Black flux, or charcoal, the arsenious acid be heated in a glass tube with quick-lime, a sudden ignition will take place, when one part of the white arsenic will be metallized, and the other farther acidified, so as to produce an arseniate of lime; in this case, therefore, a certain portion of the arsenious acid is robbed of its oxygen to complete the acidification of the rest.
The habitudes of arsenious acid with the nitrates, as first observed by Kunkel, deserve also some attention. If they be heated together, the former will be oxygenated at the expense of the nitric acid, nitrous acid vapour will be disengaged, and an arseniate of potass remain. The forensic chemist may avail himself of these facts, and obtain a very useful test, which may be applied in the following manner.[[249]] Take a grain or two of the suspected powder, and mix it with double the quantity of Nitrate of Potass; introduce this mixture in a small glass tube, and apply the flame of a spirit lamp under the powder; when, if it contain arsenic, the nitrate will be decomposed, nitric oxide and nitrous acid be evolved in a gaseous form, and an arseniate of potass remain.
The acid vapour may be easily recognised by its colour and smell, or by placing a piece of moistened litmus paper within the tube. The arseniate may be identified by the brick-red precipitate, produced in its solution, by Nitrate of Silver. So small is the quantity of arsenic required for this latter mode of trial, that Mr. Smithson, in a late paper, observes “that a drop of a solution of arsenious acid in water, which at the height of 54·5 Fah. contains not more than 1/80th of the acid, put to nitrate of potass in a platina spoon, and fused, affords a considerable quantity of arseniate of silver. Hence when no solid particle of oxide of arsenic can be obtained, the presence of it may be established by infusing in water the matters which contain it.”[[250]]
B. By the application of certain re-agents, or tests, to its solutions.
a. Fused Nitrate of Silver, or Lunar Caustic. For this test we are indebted to Mr. Hume, who first suggested its application in the Philosophical Magazine for May 1809, (vol. xxxiii). His method of using it is as follows: into a clean Florence flask introduce two or three grains of the suspected substance, in the state of powder, to which add about eight ounces of rain or distilled water, and heat the solution until it begins to boil; then while it boils frequently shake the flask, and add to the hot solution a grain or two of sub-carbonate of potass, agitating the whole to make the mixture uniform. Pour into a wine glass about two table spoonsful of the solution, and touch the surface of the fluid with a stick of lunar caustic. If arsenic be present, a beautiful yellow precipitate will instantly proceed from the point of contact, and settle towards the bottom of the glass as a flocculent and copious precipitate. By this test the 60th part of a grain may be satisfactorily recognised in two ounces of water. The presence of some alkali is essential to the success of the experiment, since arsenious acid is incapable, by the operation of simple affinity, to decompose the nitrate of silver.[[251]] The validity of this test has been questioned on several distinct grounds, and which the author has endeavoured to answer in another work[[252]]; such, however, is the importance of the question in its judicial consequences, that we shall re-consider it on the present occasion.
Objection 1. The alkaline Phosphates are found to produce precipitates with silver, analogous in colour and appearance to the arsenite of silver. This constituted one of the principal points in the evidence for the defence, on the trial of Donnall for the murder of Mrs. Downing (see Appendix, p. 299), and it must be admitted as a valid objection, if the experiment be performed in the manner just stated; but there are other reagents which will immediately distinguish these bodies, as we shall presently have occasion to state, under the history of the Ammoniuret of silver, as a test for arsenic. The author has also shewn that there is a mode of so modifying the application of the present test, that no error or doubt can arise in the use of it, from the presence of any phosphoric salt. This method consists in conducting the trial on writing paper, instead of in glasses; thus—drop the suspected fluid on a piece of white paper, making with it a broad line; along this line a stick of lunar caustic is to be slowly drawn several times successively, when a streak is produced of a colour resembling that known by the name of Indian Yellow; and this is equally produced by the presence of arsenic, and that of an alkaline phosphate, but the one from the former is rough, curdy, and flocculent, as if effected by a crayon, that from the latter is homogeneous and uniform, resembling a water-colour laid smoothly on with a brush; but a more important and distinctive peculiarity soon succeeds, for, in less than two minutes the phosphoric yellow fades into a sad green, and becomes gradually darker, and ultimately quite black; while, on the other hand, the arsenical yellow remains permanent, or nearly so, for some time, when it becomes brown. In performing this experiment the sun-shine should be avoided, or the transitions of colour will take place too rapidly. It would be also prudent for the inexperienced operator to perform a similar experiment on a fluid known to contain arsenic, and on another with a phosphoric salt, as a standard of comparison.
In this way the nitrate of silver, without the intervention of any other test, is capable of removing every ambiguity, and of furnishing a distinguishing mark between the chemical action of arsenic and that of the phosphates. Mr. Hume[[253]] states that he has repeated this modification of his experiment with entire satisfaction; and that, in a late unfortunate case of poisoning, he derived considerable information by its application. One of the great advantages of this test is the very small quantity that is required for examination, and which will therefore never prevent our pursuing the subject through the other channels of investigation.
Objection 2. The muriates produce precipitates with silver, so copious and flocculent, as to overcome every indication which the presence of arsenic would otherwise afford.
From the general use of common salt, the chemist must be prepared to meet with a muriate in almost every examination after arsenic, besides which this latter substance is occasionally adulterated with the muriate of baryta and by sulphate of lime. Dr. Marcet proposes to obviate the difficulties which the presence of a muriate must occasion, by adding to the fluid to be examined dilute nitric acid, and then cautiously applying the nitrate of silver until all precipitation ceases; in this way the muriatic acid will be entirely removed, while the arsenic, if present, will be retained in solution, and may be afterwards rendered evident by the affusion of ammonia, which will instantly produce the yellow precipitate in its characteristic form. It must, however, be confessed, that this mode appears complicated, and, moreover, requires some chemical address for its accomplishment; it should be also known that the yellow precipitate thus produced is not always permanent, for it is soluble in an excess of ammonia. Under these circumstances, it is surely preferable to precipitate at once from the fluid under examination, all the substances which nitrate of silver can affect, and then to expose the mixed and ambiguous precipitate, so obtained, to a low heat, in a glass tube, when the arsenious acid will be separated by sublimation. In this way the presence of muriates and even phosphates, may, in certain cases, be serviceable, especially if the quantity of arsenic be very minute; for, by increasing the bulk of the precipitate, we shall decrease the difficulty of its examination.
Objection 3. Chromate of potass produces with nitrate of silver a yellow precipitate, which, when placed side by side with one produced by arsenious acid, cannot be distinguished by colour or appearance from it. This fact has lately been announced by Dr. Porter, of the University of South Carolina (Silliman’s Journal, iii. 355); but as the presence of Chromate of Potass can never be suspected in any research after arsenic, in cases of forensic interest, it is unnecessary to enter into any details respecting it.
We have stated above, that in consequence of the inability of arsenious acid to decompose nitrate of silver by simple elective attraction, the presence of some alkali becomes indispensable in the examination; and for this purpose Dr. Marcet suggested the superior advantages which would attend the application of ammonia, in all those cases where the arsenic had not been previously combined with a fixed alkali; since the former does not, when added singly, decompose nitrate of silver; a circumstance which, in using the fixed alkalies, is very liable to occasion fallacy. This led Mr. Hume to improve his original plan, by forming at once a compound,[[254]] which he calls the Ammoniaco-nitrate of silver, but which may with more propriety be designated, as an ammoniuret of that metal.
b. The Ammoniuret of Silver. This is an improvement of considerable value; for, while it obviates the necessity of ascertaining the exact proportion[[255]] of alkali required in each experiment, it possesses the desirable property of not in the least disturbing the solution of phosphate of soda.
c. Sulphate of Copper. This test of arsenic is the one discovered by Scheele; when added to the arsenite of potass a beautiful green precipitate (constituting a pigment known by the name of Scheele’s green) is produced; “so decidedly,” says Dr. Bostock, “does this phenomenon indicate the presence of arsenic, that I thought it desirable to ascertain, as exactly as possible, what were the best proportions in which the ingredients should be employed, and in what way they should be mixed, so as to exhibit the effect in the most obvious manner. After a number of trials, in which the substances were employed in various quantities, and under different circumstances, I am disposed to recommend that the proportions of the arsenic, the potass, and the sulphate of copper, should be to each other as the numbers one, three, and five, respectively; for instance, if one grain of arsenic and three grains of potass, be dissolved in two drachms of water; and, in another equal quantity of water, five grains of sulphate be dissolved, we have two solutions, which are transparent, and nearly colourless; but upon mixing them together, the whole is converted into the most beautiful grass-green, from which a copious precipitate of the same hue slowly subsides, leaving the supernatant fluid nearly without colour. If the same materials are employed, in the same manner, but without the arsenic, a delicate sky-blue is formed, which is so decidedly different from the former colour as not to admit of the possibility of error.” In this experiment then, as well as in that with the nitrate of silver, it is necessary that the arsenious acid should be combined with an alkaline base; and for the same reason, in order to bring the double elective attractions into play; Mr. Hume has accordingly availed himself of the property of ammonia, to form an ammoniuret of copper, which is to be made according to the formula already given for the preparation of the silver test.
d. Ammoniuret of Copper. In using this test care must be taken that it be not too highly concentrated, for in that state it will not produce precipitation.
Notwithstanding the confidence with which Dr. Bostock has supported the pretensions of the Sulphate of Copper, as an infallible test for arsenic, its validity has been lately called in question, and it has been stated that a decoction of onions has the property of imparting to the copper precipitate, produced by a fixed alkali, a green colour and appearance completely analogous to that which is occasioned by the presence of arsenic. This opinion was boldly advanced, and supported, on the trial of Donnall, before alluded to, and of which we have given a very ample report in the Appendix. Since this event an opportunity occurred which enabled the author to examine this alleged fact, by a fair and appropriate series of experiments,[[256]] the result of which has satisfactorily proved that the opinion was grounded on an optical fallacy, arising from the blue precipitate assuming a green colour, in consequence of having been viewed through a yellow medium.[[257]] The phosphoric salts may also, under similar circumstances, be mistaken for arsenic; for the intense blue colour of the phosphate of copper will, when viewed through a yellow medium, necessarily appear green. Such instances of optical fallacy are by no means uncommon in the history of chemical reagents; thus corrosive sublimate has been said to possess alkaline characters, in consequence of appearing to turn the syrup of violets green, whereas this apparent change is to be solely attributed to the optical combination of the yellow hue of the sublimate with the blue colour of the violet.
Whenever therefore such a source of fallacy can be suspected, the operator would do well to repeat his experiment on white paper, in the manner we have already pointed out, when treating of the silver test; and let it be remembered that the results, when obtained in glasses, should always be examined by day light, and viewed by reflected, and not by transmitted light. Dr. Bostock observes, that a weak solution of the sulphate of copper, without any addition, when held between the eye and the window, frequently presents a greenish tinge. It should be also known that the usual reaction of the ammoniuret of copper, upon a diluted solution of arsenic, is prevented by the presence of tannin; strong tea may therefore render the test inefficient.
e. Sulphuretted hydrogen. This is a very delicate test for arsenic, producing with its solution a beautiful golden coloured liquor, which, after a short time, lets fall a precipitate, and which will take place sooner if a small quantity of acetic acid be added. By this re-agent so small a quantity as 1/100000 may be detected in solution. The test, however, is not, says Dr. Bostock, sufficiently discriminative to be depended upon alone; since tartarized antimony and some other bodies, will produce phenomena that may be mistaken for the effects of arsenic. It has, however, the merit of not being affected by tannin, and may therefore be conveniently employed for precipitating arsenious acid, when dissolved in tea.
f. Lime water produces with the solution of arsenic a beautiful white precipitate of arsenite of lime, which easily dissolves in an excess of arsenious acid.
The precipitates occasioned by the foregoing reagents, should be carefully collected, and treated with black flux, in a glass tube, for the purpose of obtaining the metallic sublimate, as above described.
We cannot quit this part of our subject without directing the reader’s attention to the chemical evidence given by Dr. Addington, on the trial of Mary Blandy (see Appendix, p. 241) to prove that arsenic was contained in a powder with which she was supposed to have poisoned her father. To those in the least acquainted with the habitudes of arsenious acid, it must be evident, that no one of the appearances described by Dr. Addington indicates the presence of arsenic;[[258]] and his evidence is only to be reconciled upon the supposition that, instead of the arsenic itself, he, in this case, detected the foreign substances with which it had been adulterated; thus it has been before stated that white arsenic, as sold by the druggists, is often adulterated with sulphate of lime; and the decomposition of this substance by the sub-carbonate of ammonia (“Spirit of sal-ammoniac”) or by the sub-carbonate of potass (“Lixivium of tartar”) would occasion the precipitation of a white substance, as stated in the evidence; it is however difficult to account for the “considerable precipitation of a lightish coloured substance” by muriatic acid (spirit of salt) by the presence of any impurity likely to be contained in the arsenic, or in the water employed for its solution. If any lime were present, it would probably give “white glittering crystals” of sulphate of lime, by the addition of sulphuric acid (spirits of vitriol). The only plausible evidence of the presence of arsenic in the suspected powder is “the alliaceous smell and white flowers” which Dr. Addington describes as occurring when it was thrown on red hot iron; it must however be confessed, that from the fallacy of the other experiments, it is even impossible to place any confidence in those last mentioned.
Arsenic does not blacken a knife by which it is cut, as stated on the trial of Eliza Fenning; nor does it, when mixed with dough, prevent its rising.[[259]]
We have now concluded our history of the different tests which have been proposed for the detection of arsenic. Much has been said and written upon the relative degree of confidence to which they are respectively entitled, and it has been asserted on several occasions, that nothing short of the reproduction of the metal ought to be received by the tribunals of justice, as an unequivocal proof of the presence of arsenious acid. (See Dr. Neale’s Evidence on the trial of Donnall. Appendix, p. 297.) In taking an impartial review of all the evidence which the investigation of this subject can furnish, it must appear to the most fastidious, that the Silver and Copper tests, above described, are capable, under proper management and precaution, of furnishing striking and infallible indications; and that in most cases they will be equally conclusive, and in some even more satisfactory in their results, than the metallic reproduction upon which so much stress has been laid; and for this obvious reason, that unless the quantity of metal be considerable, its metallic splendour and appearance is often very ambiguous and questionable. The author is personally acquainted with a case, where the medical person, by no means deficient in chemical address, actually ascribed the presence of arsenic to that which was no other than a film of finely divided charcoal: in this state of doubt the last resource was to ascertain whether it yielded, or not, upon being volatilized, an alliaceous odour. Surely an unprejudiced judge would prefer the evidence of sight, as furnished by the tests, to that of smell, as afforded in the experiment to which we allude; especially after the various fallacies, which we have shewn in the course of the present enquiry, to have occurred with regard to this latter sense. But the question at issue may be easily disposed of to the satisfaction of all parties; for let it be remembered, that the application of chemical reagents on solutions suspected to contain arsenic, so far from throwing any obstacle in the way of the metallic reproduction of that substance, are the very steps which should be adopted as preparatory to the “experimentum crucis.” It is only necessary to collect the precipitates, and to decompose them in the manner already described; and this confirmation of our results should never be neglected, for it is the bounden duty of the forensic chemist, who is called upon to decide so important a question as the presence of a corrosive poison, to prosecute by the fullest enquiry every point which admits of the least doubt; he should also remember that in a criminal case, where the life of a human being depends upon his testimony, he has not only to satisfy his own conscience, but that he is bound, as far as he is able, to convince the public mind of the accuracy and truth of his researches.
2. The Arsenious Acid is mixed with various alimentary and other substances.
The detection of the presence of arsenic, amidst a complicated mass of alimentary matter, has long been a problem of interest and difficulty. In the directions which have been already offered for the discovery of arsenic in solution, we have in some measure anticipated several of the resources, of which we are now to avail ourselves. It has been seen how greatly coloured fluids are capable of obscuring, and changing, and even altogether preventing, the arsenical indications. M. Orfila, with an assiduity and accuracy which so eminently characterise all his toxicological labours, has accordingly investigated the peculiar appearances assumed by the arsenical precipitates in different media, such as bile, tea, coffee, wine, broth, jelly, &c. Since the publication of the great work[[260]] in which these phenomena are recorded, its author has proposed a new method[[261]] of removing its difficulties and embarrassments, occasioned by the colouring matter of the above media; which consists in a previous application of Chlorine, so as to change the colour to a shade, that will not offer any optical impediment to the characteristic indications of the tests in question. We are ready to admit that such a mode of proceeding may, on certain occasions, assist the accomplished chemist in his analysis; but in the hands of a person less accustomed to chemical manipulation, we hesitate not to declare that it is subject to fatal fallacies; whereas, by collecting the precipitate, and submitting it to the process of sublimation we shall at once obtain the arsenious acid in a pure form, and be enabled to test it, in distilled water without the chance of error. Why then should we attempt to pursue our game through the windings of a labyrinth, when a direct road lies before us by which we may drive it into the open plain?
We accordingly recommend the juridical chemist, who suspects the presence of arsenious acid in broth, coffee, or any coloured liquid, to add a solution of ammoniuret of silver, and thus to precipitate indiscriminately all the bodies which it may be capable of so affecting. The precipitate may then be collected, and submitted to heat in a glass tube, as before directed.
But the Arsenious acid may perchance be so mixed with various foreign matter as to render its separation by filtration difficult; in such a case, after having boiled it in distilled water, in order to procure all the soluble matter from it, the residual mass may be evaporated to dryness, care being taken that the heat applied for such a purpose never exceeds 250° Fah. or we shall lose the arsenic, should any be present, by volatilization. The residue thus obtained may then be submitted to a higher temperature in a subliming vessel, in order to procure the arsenious acid in its pure state. This process applies particularly to the examination of the matter vomited, or the feculent evacuations passed, by the patient. Should the arsenious acid have, in the first instance, been dissolved in oil, Dr. Ure proposes to boil the solution in distilled water, and to separate the oil afterwards by the capillary action of wick threads. If the arsenious acid be mixed with resinous bodies, Oil of Turpentine may be employed as their solvent, which will leave the arsenic untouched. Dr. Black directed the application of alcohol for this purpose, but this is obviously improper, since arsenious acid is soluble in that fluid.
If the physician be called upon to investigate the contents of the alimentary canal after death, and the arsenious acid cannot be discovered amongst the suspected matter, the stomach itself must be cut into small pieces, and in compliance with the directions of Orfila, boiled in ten or twelve times their weight of distilled water, which should be renewed as fast as a portion of it flies off in vapour; this liquor should be cooled and decanted, in order to put a few drops of it into the solutions of the different re-agents which we have before described. If the precipitates should indicate the presence of arsenic, we may proceed according to the directions we have already laid down; if, on the other hand, the fluid offers no indication of poison, the mass exhausted by water should be treated, according to the process suggested by Rose, by boiling it for some time in a solution of potass, by which means the stomach will be partly decomposed and dissolved, and the arsenious acid, with which it might have been combined, saturated by the alkali. In this state the liquor is to be filtered, again boiled, and nitric acid added, little by little, until it passes from a dark to a clear yellow colour. The object of the acid in this stage of the process being to decompose and destroy the animal matter. The excess of acid should be saturated with potass, when an Arsenite of Potass will be formed, if there really existed any arsenious acid in the stomach. This M. Orfila recommends us to precipitate by the Hydro-sulphuret of Ammonia, and a few drops of nitric acid; (Rose prefers lime water for the same purpose); a yellow sulphuret of Arsenic will be the result, from which the whole of the metal may be obtained, by drying it upon a filter, mixing it with an equal bulk of potass, and melting it in a small glass tube.
This complicated mode of proceeding will rarely be found necessary; but it should not be neglected, where the presence of arsenic cannot be otherwise detected in the alimentary canal of those who are suspected to have died from its ingestion, especially in the examination of a body where, from the length of time it may have been under ground, there is reason to suppose that the acid exists in a state of intimate combination with the animal matter. And we may take this opportunity to observe, that advanced putrefaction, however disagreeable it may render such researches, will not, in the case of arsenic, defeat their success; let the forensic physician, then, remember, that the length of time which may have elapsed since the death of the body, ought never to be urged as a plea for not having proceeded in its dissection. The task may be personally disagreeable, but it will be less painful than the reflections which must attend a breach of duty; upon such an occasion we would address the anatomist in the quaint but expressive words of Teichmeyer[[262]], “Præstat enim manus quam conscientiam cruentare et contaminare.”
Arsenic Acid, and its Salts.
It has been stated, that the Metal Arsenic is susceptible of two degrees of oxidizement, the result of its first degree being Arsenious acid, and that of its second Arsenic acid. This latter compound, of which we are now to treat, may be obtained by the repeated distillation of white arsenic with nitric acid. In a solid state it is white, not crystallizable; of a sour, and at the same time, metallic taste; its specific gravity is 3·391; when exposed to the action of heat in a close vessel, it does not become volatile, but melts and vitrifies; thrown on burning coals, it swells, parts with its water, and becomes opaque; if the process of deoxidation be continued, it will, at length, rise in vapours, like those of arsenious acid, and which, like them, will yield an alliaceous odour, or not, according to the circumstances already explained. The Arsenic acid dissolves very readily in water, and is even indeed deliquescent. With alkalies, earths, and oxides, it constitutes a class of salts, called “Arseniates,” all of which, as well as the pure acid, are extremely active poisons; fortunately, however, they are not much employed[[263]] in this country, and are not likely to become the instruments of crime. These salts, like those of the arsenious acid, are obedient to the different re-agents which were enumerated under the consideration of this latter substance, but with different results; thus the silver test, instead of producing the yellow indication, occasions an equally characteristic precipitate of a red, or brick colour. The ammoniuret, and acetate of copper, furnish a bluish-white precipitate. The arsenic acid, in a solid form, or the arseniate, mixed with black flux, will, like white arsenic, furnish a metallic sublimate, when heated in a glass tube.
The Sulphurets of Arsenic.
There are two Sulphurets of Arsenic: the yellow variety known in commerce under the name of Orpiment, and the red sulphuret, termed Realgar. The bodies, as they occur native, do not appear to be endowed with the virulent powers which distinguish the other compounds of arsenic. M. Renault[[264]] gave as much as two drachms of the native orpiment to dogs of different sizes, from which they experienced no inconvenience. Hoffman[[265]] also offers his testimony of the inertness of this substance. The same observations apply to the Realgar. It is not a little singular that while these native sulphurets of arsenic should be so harmless, those which are produced by artificial fusions, are extremely virulent in very small doses. M. Renault supposed that this remarkable difference of effect was owing to the arsenic being oxidized in the latter compound, and in its metallic state in the former. This explanation, however, is not considered as satisfactory by M. Orfila, who states that it does not embrace all the varieties of the case, for that the sulphuret, which is artificially obtained by pouring the arsenious acid into a solution of sulphuretted hydrogen, is as inert as the native compounds; besides which, chemical analysis has proved that there is no oxygen in any of these sulphurets, and that they only differ from one another, by a greater or less proportion of their two ingredients. This apparent anomaly induced M. Orfila to institute a series of experiments for its investigation, but the results which he has obtained are too unsatisfactory to enable him to decide the question.
The presence of an Arsenical Sulphuret is to be sought for by calcination with caustic potass, in a small glass tube. The sulphuret is decomposed in a few seconds, yielding its sulphur to the potass, while its metallic element is volatilized with the usual phenomena.
Mercury.
Mercury, or Quicksilver[[266]], was known in the earliest ages. Its external characters are too familiar to require any particular description in this place. Its specific gravity is 13·568.[[267]] In its metallic state it exerts no action on the living system, except that which may depend upon its mechanical properties, although a different opinion has been entertained, (see Pharmacologia, art. Hydrargyrum.)
Several of the combinations of this metal are, however, highly destructive in small doses, and are consequently objects of forensic interest.
Corrosive Sublimate.
Oxy-muriate of Mercury. Bi-chloride of Mercury.
This metallic salt is by far the most active of all the mercurial preparations. According to the latest views of Chemistry it is a compound of two proportionals of chlorine, and one proportional of metallic mercury, and is therefore a bi-chloride of Mercury. It generally occurs in the form of a crystalline mass, made up of very small prismatic crystals, which undergo a slight alteration by exposure to air, becoming opaque and pulverulent. Its taste is extremely acrid, with a metallic astringency, occasioning a sensation of obstruction in the throat which continues for some time. Its specific gravity is 5·1398[[268]]. When pulverised and thrown upon burning coals, it is immediately volatilized, giving out a thick white smoke, of a very pungent smell, not at all resembling garlic, but which irritates the mucous membranes extremely, and is highly dangerous to those who breathe it. It is soluble in eleven parts of cold, and in three of boiling water; and this solubility may be farther increased by the addition of a few drops of rectified spirit, or of muriatic acid. When swallowed in small quantities it acts as a most virulent poison.[[269]]
Symptoms of Poisoning by Corrosive Sublimate.
The effects, as well as the modus operandi, of this salt, will vary with the quantity swallowed. We shall, therefore, first consider the acute symptoms which supervene a dose sufficiently powerful to destroy life in a few hours; and afterwards those which may arise from its long continued use in small quantities, and at different intervals.
1. Symptoms which follow a large dose. A most painful burning and sense of constriction is experienced in the fauces; dryness of the mouth and lips; excruciating pain in the stomach and bowels, increased by the slightest pressure, and generally attended with considerable distention; excessive vomiting and purging of frothy mucus; the countenance is frequently red and swollen, and the eyes exhibit a sparkling appearance, accompanied by contraction of the pupils. The pulse is in general quick, small, and hard; suppression of urine takes place, and cold sweats; anxiety; universal pains; convulsions, and death. If the patient survives long enough, a violent ptyalism, and sloughing of the mouth and gums may take place.
2. Symptoms which are produced by the repetition of small doses. In this case the mercurial salt acts as an “Accumulative Poison.” (See page [148]). The most striking of the symptoms are those arising from its specific action upon the salivary glands, in consequence of which an increased flow of saliva takes place, the gums become tender and sore, the breath intolerably offensive, and if the use of the salt be not discontinued, the teeth loosen, and even fall out, and their loss is sometimes followed by that of the bones of the palate, or maxillæ; at the same time other evils, although perhaps less apparent, soon arise; the strength and muscular powers of the body begin to fail; emaciation proceeds rapidly; cardialgia, dyspepsia, diarrhæa, and a train of morbid symptoms succeed; violent pains are experienced in the muscles, tendons, or joints; tremors of the limbs, and even paralysis may result; and in some cases, pulmonary consumption terminates the existence of the unhappy sufferer. It has been asserted that Corrosive Sublimate, when taken for a long time in small quantities, will sometimes occasion all the symptoms of debility above enumerated, together with hectic fever, without producing salivation. This is a truth which the author’s personal experience will enable him to confirm. The Countess of Soissons, mother of the celebrated Prince Eugene, was accused, at the latter end of the seventeenth century, of having destroyed her husband by these means. A question of considerable importance has arisen, with regard to the specific effects of mercury, which demands some notice in this place. Whether salivation, after having entirely subsided, can ever return without a fresh exhibition of Mercury? Two instances are related by Dr. Mead of the return of salivation, after an interval of several months, when not a particle of mercury had been administered, in any form, during that period.[[270]] Dr. Male, in his work on Juridical Medicine,[[271]] relates an analogous case which occurred in his own practice: “In March, 1815,” says he, “I gave a small quantity of triturated mercury to a respectable woman in this town, who had been long ill; she became suddenly and unexpectedly salivated. She soon recovered, and enjoyed better health than she had done for a considerable time. In October, without (as she informed me) having taken any medicine whatever, the salivation returned with extreme violence, her mouth sloughed and mortified; and in a few weeks she died.” Dr. Hamilton, the Professor of Midwifery in Edinburgh, relates in his lectures the case of a married lady, who had been under the necessity of going through a course of mercury, under the care of the late Mr. Bennet, who, from motives of delicacy did not enquire very minutely into the particular circumstances; but, according to the rule of the day, gave his patient a sore mouth. Four months afterwards she miscarried, and salivation again came on. It was removed for a week, at the end of which it returned, and harrassed her for about twelve months.[[272]] The author, in his Pharmacologia,[[273]] has cited a case from Hufeland’s Journal, (vol. ix) wherein mercurial influence, after its complete subsidence, had been renewed by doses of opium. In the trial of Miss Butterfield, at the Croydon assizes, for poisoning Mr. Scawen, in the year 1775, the merit of the case entirely hinged upon this question. See vol. 1, p. 303.
Physiological action of Corrosive Sublimate.
When this salt is introduced into the stomach in a large dose, it immediately exerts a corrosive action on that organ, in consequence of which the heart and brain become sympathetically affected, and death results from the suspension of their functions. For this view of the modus operandi of this mercurial salt we are indebted to Mr. Brodie,[[274]] whence it would appear that its physiological action is very different from that of arsenious acid; the former acting as a simple escharotic, on the coats of the alimentary canal, the latter requiring to be absorbed, before it can display its energies. These observations, however, apply only to those cases in which the quantity of poison has been so considerable as to destroy life in a few hours; where the dose has been small, and the symptoms have arisen from its frequent repetition, the salt produces its effects by a different mode of operation. In this latter case it is absorbed, and carried into the current of the blood, so as to be distributed to every part of the living system; and it has been asserted that, after the long continued and improper use of mercury, it has been discovered in different parts of the body, and even in the brain, in the form of globules. In this way then deleterious effects may arise from the external application of corrosive sublimate, and numerous instances are recorded where such consequences have followed the injudicious use of lotions and plasters, into which it had entered as an ingredient.[[275]] In the Medical Repository, for December, 1821, Mr. Sutleffe has communicated the case of a girl of five years of age, who became salivated, and died, in consequence of an application made to the head for tinea capitis, consisting of pomatum rubbed up with a few grains of corrosive sublimate.
Antidotes to Corrosive Sublimate.
After the view which we have taken of the operation of this salt in large doses, it necessarily follows that copious dilution is the very first object which we have to accomplish, and then the ejection of the fluid by vomiting. Sydenham relates an interesting case of poisoning by this substance, which was successfully treated by copious draughts of water, and repeated vomiting.[[276]] But it becomes a question of great practical importance to enquire, whether there may not exist some counterpoison or antidote which, by decomposing the salt, will at once disarm it of its virulence? This question has been investigated in a very masterly style by Orfila, who has clearly proved by experiment, that neither the alkaline salts and earths, the sulphurets of potass and of lime, nor the martial alkaline tinctures, as proposed by Navier,[[277]] deserve the least confidence; for although the salt may by some of these bodies be decomposed, yet the resulting oxide will prove as virulent as the original compound; equally inefficient are the other substances which have been proposed as counter-poisons, such as sulphuretted hydrogen, solutions of sugar,[[278]] the infusions of Peruvian bark,[[279]] and metallic mercury.[[280]]
M. Orfila having observed the facility with which albumen decomposes corrosive sublimate, and gives rise to a triple compound of albumen, muriatic acid, and protoxide of mercury, induced him to ascertain by experiments whether the white of eggs might not prove an antidote to that poison; the result of his inquiry has shewn that this is the case; and that by mixing such albuminous matter, in large quantities, with the diluents given to provoke vomiting, the happiest effects may be anticipated. Many examples are recorded of the success of this practice. In the Transactions of the King and Queen’s College of Physicians in Ireland, an interesting case of this kind is related by Dr. Lendrick; it is, however, but justice to state, that there are instances also of the failure of this antidote. In the 41st volume of the London Medical and Physical Journal, p. 204, the reader will find the case of a girl who was poisoned by a drachm of sublimate, and who, notwithstanding the copious administration of albumen, died in ninety hours afterwards.
It has lately been discovered that vegetable gluten, as existing in wheat flour, is capable of producing upon corrosive sublimate the same chemical decomposition, as that which we have stated to arise from the action of albumen; whence the administration of wheat flour and water has been suggested as a ready antidote. On the trial of Michael Whiting, for administering poison (corrosive sublimate) to his brothers-in-law, George and Joseph Langman, the housekeeper, Catharine Carter, stated in evidence, that the flour, (which was subsequently proved to contain corrosive sublimate) could scarcely be made into dumplings with milk[[281]]; and another witness, Mrs. Hopkins, a neighbour who took charge of the dumpling that had not been boiled, described it as “a comical sort of paste; like glazier’s putty more than paste, though not greasy.” In order to ascertain the correctness of this statement, we mixed powdered sublimate with wheat flour, and proceeded to make it into dough with milk; when the same difficulty as that stated by the above witnesses, embarrassed the process, and satisfied us of the truth of their testimony. The phenomenon would appear to depend upon the mutual chemical changes which arise in the gluten and mercurial salt.
Organic Lesions discovered on Dissection.
The œsophagus and stomach will be found inflamed, and sometimes eroded, as in poisoning by arsenic. Salin has asserted, that this salt never produces perforation of the intestinal tube; this, however, is not the fact; and we know not of any exclusive appearances, by which the organic lesions inflicted by this poison can be distinguished, unless indeed it be the black appearance of the stomach, as if it had been burnt, which occasionally presents itself.
Of the Chemical Processes by which the presence of Corrosive Sublimate may be detected.
As the chemist, devoted to forensic enquiry, will be required to identify this substance under very different states of mixture and combination, we shall proceed to enumerate the various obstacles that may possibly oppose his researches; and, at the same time, to suggest the expedients by which they may be successfully evaded. Unlike arsenious acid, corrosive sublimate is so readily decomposed by various alimentary substances, that, when we attempt to demonstrate its presence in such mixtures, we shall be more frequently compelled to rest our proof upon the products of the analysis, than upon the actual reproduction of the salt.
We shall proceed to consider the best modes of establishing the presence of this salt, in the different forms in which it may occur, viz. 1, In the solid form; 2, Dissolved in water or spirit; 3, In various coloured liquids; 4, In a state of mixture with various solids; 5, Combined with solid or liquid aliments, by which it undergoes decomposition; 6, In a state of combination with the textures of the alimentary canal.
1. The sublimate is in its solid form. The external characters by which this salt is distinguished will go far to establish its identity; but the fact should always receive the support of a chemical proof; and as this is to be derived from the phenomena afforded by its solutions through the intervention of various tests, it will meet with full consideration in the following section, viz.
2. The salt is in the state of solution, in water, or spirit. Let us then suppose that we have a solution of some body in distilled water, which we suspect to be corrosive sublimate, by what means are we able to identify it?
(a) By its metallization, through the agency of galvanism. We are indebted to Mr. Sylvester for first suggesting the mode by which galvanic electricity might be applied for the detection of minute quantities of corrosive sublimate in solution. His method is as follows. A piece of zinc or iron wire, about three inches in length, is to be twice bent at right angles, so as to resemble the greek letter π, the two legs of this figure should be distant about the diameter of a common wedding ring from each other, and the two ends of the bent wire must afterwards be tied to a ring of this description. Let a plate of glass, not less than three inches square, be laid as nearly horizontal as possible, and on one side drop some sulphuric acid, diluted with about six times its weight of water, till it spreads to the size of a halfpenny. At a little distance from this, towards the other side, next drop some of the solution supposed to contain corrosive sublimate, till the edges of the two liquids become joined; and let the wire and ring, prepared as above, be laid in such a way, that the wire may touch the acid, while the gold ring is in contact with the suspected liquid. If the minutest quantity of corrosive sublimate be present, the ring, in a few minutes, will be covered with metallic mercury on the part which touched the fluid.
The above experiment may be beautifully simplified in the following manner[[282]]. Drop a small quantity of a solution, supposed to contain the salt in question, on a piece of gold, and bring into contact a key, or some piece of iron, so as to form a galvanic circuit; when, if sublimate be present, the gold will immediately be whitened.
A solution of nitrate of silver will, under similar treatment, occasion on gold a white precipitate; but as no amalgamation takes place, it is readily wiped off, and cannot therefore occasion any fallacy.
(b) By precipitating metallic mercury from its solution, by the contact of a single metal. It should be generally known that, by virtue of superior affinity, certain metals will decompose the solution of corrosive sublimate, with different phenomena; in those cases where the precipitating metal is capable of forming a direct union with mercury, we shall find the precipitates to consist of an amalgam of the metal employed; where no such combination takes place, the mercury may be frequently seen standing on the surface as a metallic dew. This is particularly striking when iron or steel has been employed. In the evidence given on the trial of Mary Bateman[[283]], better known by the name of the “Yorkshire Witch,” Mr. Thomas Chorley, surgeon at Leeds, stated that he had received from his assistant, Mr. Hammerton, a jar which he had carefully preserved in his possession, and of the contents of which he gave the following account. “Upon tasting a portion, it was very acrid, styptic, and permanent upon the tongue; I then took a small quantity of it upon a clean knife, and rubbed it with my finger; a change of colour immediately appeared; further rubbing produced numerous globules of quicksilver, and the knife was, at the same time, blackened by it; this change of colour led me to suspect that it must be a mercurial composition, and having made a solution of it, and subjected it to a series of tests and experiments, it is my opinion, that the mixture in the pot did contain honey, and corrosive sublimate of mercury. In order, however, more fully to satisfy myself upon this point, a mixture was made of these ingredients, when it was found to yield the same results.” In the above experiment, the steel knife decomposed the sublimate, forming a chloride of iron, while the mercury, thus disengaged in its metallic form, being unable to amalgamate with the iron, appeared in globules[[284]] upon its surface. At the same time the knife became blackened owing to the precipitation of carbonaceous matter from the steel.
(c) Carbonate of Potass. A saturated solution of this salt, added to that of corrosive sublimate, will produce a deep brick coloured sediment, which is stated to consist of per-carbonate of mercury[[285]]; while a muriate of potass will be found to remain in solution. The sub-carbonate of potass will occasion a somewhat different precipitate, of a clear brick colour, and consisting of a mixture of the carbonate, and oxide of the metal.[[286]]
(d) Ammonia. A solution of the volatile alkali produces a white precipitate, which is an insoluble triple salt, composed of muriatic acid, ammonia, and oxide of mercury; being heated it grows yellow; it passes afterwards to red, and according to Orfila gives out ammoniacal gas, nitrogen, calomel, and metallic mercury. In this operation the oxide of mercury is supposed to be deoxidized by the hydrogen which results from a portion of the decomposed ammonia.
(e) Lime water. This reagent may be said to decompose corrosive sublimate more perfectly than any alkaline body; occasioning a precipitate of a deep yellow colour, which will be found to be a peroxide of mercury; unless indeed the quantity of lime water be very small, when it will be a sub-muriate of the peroxide.
(f) Nitrate of Tin. According to Dr. Bostock[[287]] this test is capable of detecting the three-millionth part of a grain in solution. A single drop will produce an immediate and copious dark-brown precipitation.
All the above precipitates, if rubbed on a bright plate of copper, will render its surface silvery white, in consequence of the amalgamation which takes place.
Brugnatelli has lately proposed a method of distinguishing corrosive sublimate from arsenic, which we have repeated to our satisfaction; but the experiment requires some nicety of manipulation to secure its success. Take a quantity of fresh wheat starch, mix with water, and add a sufficient quantity of iodine to give the liquid a blue colour; if either of the above poisons be now introduced into it, the colour will be destroyed, and assume a reddish tint; but if the change has been effected by the latter substance, a few drops of sulphuric acid will restore the blue colour; whereas if it has been produced by the former, it is not recoverable by such means.[[288]]
3. It is dissolved in various coloured liquids. Under this subdivision we have to consider the corrosive sublimate as existing in a state of solution, in liquids, whose colour will be liable to obscure the characteristic indications which the several reagents would otherwise occasion. It has been proposed to obviate such impediments by the previous addition of chlorine, which will discharge the colour in question. Orfila recommends such a process, where the salt has been dissolved in wine. The same objections which we urged against this mode of proceeding, under the consideration of arsenic, appear to us to apply to corrosive sublimate.
It will be preferable on these occasions to precipitate the salt by an appropriate reagent, and then to assay the precipitate for metallic mercury; or to evaporate the solution, and to submit the matter so obtained to the process of sublimation, when the sublimate may be dissolved in distilled water, and examined by the tests above described. This circuitous process may, however, in many cases be rendered unnecessary, by dropping the solution on the surface of white paper, and in such a situation proceeding to its examination by tests; when the colour of the precipitate will rarely be exposed to any optical fallacy. The Galvanic process of metallic reduction will also furnish a satisfactory solution of the problem.
4. It is mixed, or combined, with some medicinal body in a solid form. As persons have been poisoned by empirical remedies, and other medicines containing sublimate, accidentally or by design, it is necessary to point out the readiest mode by which the investigation may be pursued. If it should form part of a plaster, it will be adviseable to cut it up in small pieces, and boil them for a quarter of an hour in distilled water; this fluid, after standing for some time, should be filtered, and examined as we have before directed. It is evident that, if the sublimate is neither decomposed, nor strongly retained by the materials which compose the plaster, it ought to be found in the above solution; if, however, no such result can be obtained, the solid portion should be dried in a capsule, and mixed with potass; and in this state submitted, in the usual manner, to the process of sublimation, when the appearance of metallic globules will announce the existence of the salt in question, or, at least, of the presence of some mercurial preparation.
5. It is united with alimentary substances which have effected its decomposition. It has been frequently stated during the course of the present inquiry, that corrosive sublimate is easily susceptible of decomposition, and that various alimentary substances, of animal as well as vegetable origin, have the power of converting it into calomel.[[289]] This important fact was first noticed by Chaussier[[290]] and has been more fully investigated and confirmed by Orfila.[[291]] Where the quantity of mercurial salt has been considerable, we may generally obtain, on washing the alimentary matter, a sufficient portion for experiment; but where the dose has been small, or where it has been ejected by frequent vomiting, the whole residue may be decomposed; in which case we must seek to establish the fact of poisoning, through the detection of metallic mercury, by the processes of calcination and sublimation.
6. It is decomposed, and a part exists in intimate combination with the membranes of the alimentary canal. If all the preceding experiments have failed in detecting the presence of corrosive sublimate, it becomes our duty to examine the textures with which it may be supposed to have come in contact; the coats of the canal should be cut into pieces, and calcined with potass, when, if they have been acted upon by sublimate, they will yield metallic mercury by sublimation. “The alimentary canal,” says M. Orfila, “acts upon the sublimate like all other animal substances; muriatic acid is disengaged, and muriate of mercury ad minimum (calomel) is formed, which combines with the substance of the viscus.
It may be objected,” continues this distinguished experimentalist, “that this chemical action does not take place in the living animal; that our texture, while endued with the vital principle, is not subservient to the same laws as inorganic substances: I am not ignorant of the extent to which this objection is well-founded; but admitting the justice of it, the conclusion is not less true, that if the stomach contains corrosive sublimate at the moment of death, this body will, from that moment, act on the texture of the viscus itself. If the stomach contain a large quantity of aliment, the effects of such an action may be scarcely perceptible; but on the contrary, they will be easily applicable, should the viscus be empty, and especially if the examination of the body takes place several days after death.”[[292]]
In conducting experiments upon this, and indeed all other mineral poisons, the chemist must be prepared to meet with anomalies depending upon the impurities or adulterations of the substance under examination.
Red Oxide of Mercury. Precipitate per se.
We are not aware of any instance of death having, from accident or design, taken place in consequence of the administration of this substance; indeed its red colour, insolubility in water, and comparative rarity, will protect mankind sufficiently against mistake, and at the same time render its secret administration extremely difficult. It is, moreover, mild in its effects, unless in large doses, or, under particular circumstances of constitution. It may be identified by its form, which is that of minute crystalline scales, of a deep red colour, and by exposing it to heat in a glass tube, by which it undergoes decomposition, giving out metallic mercury, adhering to the sides of the tube, and oxygen gas, which is disengaged.
Red Precipitate, or Nitric Oxide of Mercury.
This is, strictly speaking, a sub-nitrate of mercury, and is much more poisonous than the preceding substance. Plouquet[[293]] relates the case of a man, who swallowed by accident some red precipitate, when he immediately experienced violent colics, copious vomitings, a trembling of his limbs, and cold sweats. Its external characters will at once enable the chemist to identify it.
Other Preparations of Mercury.
The various saline compounds of this metal, as the acetate, sulphate, and nitrate, are all highly poisonous, but they do not appear to us to merit a separate consideration; and more especially as we have already explained the various processes by which every variety of preparation may be identified. We may just remark that the sulphuret, better known by the name of cinnabar, or vermilion, has been known to occasion deleterious effects. Dr. Gordon Smith[[294]] states, upon the authority of Mr. Accum,[[295]] that “Vermilion has been detected as a poisonous ingredient in cheese:” this may be very true, but he should have stated at the same time, that the deleterious effects produced by it, did not arise from the mercurial sulphuret, but from the red lead with which it happened to be adulterated; and it is necessary to acquaint the forensic chemist, that such a fraud[[296]] is by no means uncommon; it may be very easily detected by burning a small portion of the suspected sample on a piece of bread in the candle, when metallic globules will announce the presence of lead; for the oxide of mercury, although revived by the process, will at the same time be volatilized. The bread by combustion affords the carbon by which the metallic reduction is effected.
The presence of very minute quantities of vermilion may, according to Mr. Smithson, be detected by the following simple experiment. Boil a portion with sulphuric acid in a platina spoon, and lay the sulphate thus produced in a drop of muriatic acid, on a piece of gold, and then bring a piece of metallic tin in contact with both, when the white mercurial stain will be produced.
Antimony.
Although the ancients were entirely ignorant of this metal, they were well acquainted with several of its combinations,[[297]] Basil Valentine, a German Benedictine Monk, was the first who described the process for obtaining it from its ore; to this work, originally written in high Dutch, and known by the title of the “Currus Triumphalis Antimonii,” which was published towards the end of the 15th century, we are indebted for almost all our knowledge respecting this metal.
Antimony is of a greyish white colour, having considerable brilliancy; its texture is laminated, and exhibits plates crossing each other in every direction; its specific gravity is 6·7021; when rubbed upon the fingers it communicates to them a peculiar taste and smell; it is very brittle, and fuses at the temperature of 809°, but does not appear to be volatile; when fused, with the access of air, it emits white fumes, consisting of an oxide of the metal, which formerly was called Argentine flowers of Antimony. When the metal is raised to a white heat, and suddenly agitated, it enters into a state of combustion, and is converted into the same white coloured oxide.
According to Thenard,[[298]] antimony is susceptible of no less than six different degrees of oxidation; Proust, however, has shewn that they may all be reduced to two, viz. protoxide and peroxide. The former of which alone exerts any sensible activity upon the human body; but this constitutes the basis of several preparations, which although in common use for medical purposes, are so extremely poisonous in larger doses, as to render them objects of interest to the forensic physician.
Emetic Tartar.[[299]] Tartarized Antimony.
This saline body appears in the state of white crystals, whose primitive figure is the regular tetrahedron, although it assumes a variety of secondary forms. Its chemical composition is still involved in some obscurity; it is stated, in the different dispensatories, to be a triple salt, consisting of tartaric acid, oxide of antimony, and potass, and that it ought therefore, according to the principles of the reformed nomenclature, to be termed a Tartrate of Antimony and Potass. The truth of these views, however, we have already[[300]] ventured to question; Gay Lussac has stated that in the various metalline compounds of which Super-tartrate of Potass is an ingredient, this latter substance acts the part of a simple acid; an opinion which receives considerable support from the great solvent property of cream of tartar, and from the striking fact that it is even capable of dissolving various oxides which are insoluble in tartaric acid, of which the protoxide of antimony is an example. In such a state of doubt, a better name could not be found than that of tartarized antimony.
The salt, according to Dr. Duncan, is soluble in three times its weight of distilled water at 212° Fah. and in fifteen, at 60°.
When it is heated red hot in an earthen crucible, it blackens, and undergoes decomposition like a vegetable body, leaving a residuum of metallic antimony, and slightly carbonated potass.
Symptoms of Poisoning by Emetic Tartar.
A question has arisen whether this salt can be considered as a poison, capable of occasioning death? In general where a large dose has been administered, it is all rejected by the vomiting which it excites; we accordingly find in the works of Morgagni and other pathologists, the history of various cases in proof of the innocence of this salt. Hoffman, however, relates the case of a woman who experienced very severe symptoms shortly after having taken tartar emetic, and that she ultimately died,[[301]] and there are other similar instances recorded in the works of Foderé and Orfila. It also deserves notice, that tartarized antimony is very liable to produce deleterious effects, where, from the insensibility of the nervous system, the operation of vomiting cannot be excited, as in apoplexy, drunkenness, and in that state of coma, which follows the ingestion of narcotic vegetables. M. Cloquet communicated to Orfila a case highly illustrative of this fact, in which a person, labouring under apoplexy, received into his stomach more than forty grains of tartar emetic, without exciting either nausea or vomiting. On opening the body, independent of the morbid state of the brain, which must be regarded as the immediate cause of death, extensive organic lesions were discovered in the alimentary canal, which could alone be attributed to the action of the tartar emetic. This fact will suggest a very important precaution to the practitioner, who may be called upon to treat a person labouring under a state of the system which will prevent the act of vomiting.[[302]].
The symptoms produced by this salt will resemble those of a corrosive poison; and where vomiting is produced, it frequently happens that although the patient may be eventually saved, an irritability of stomach, so great as to cause the rejection of all aliments, will remain for a considerable period; and Dr. Male states that in the only case of poisoning by this salt which he had ever seen, the person was affected with violent convulsions, which returned at intervals for several weeks after recovery from the immediate effects of the poison.[[303]] M. Orfila, after detailing several cases of poisoning by emetic tartar, concludes by saying that the general symptoms, upon such occasions, may be reduced to the following: a rough metallic taste; nausea; copious vomitings; frequent hiccup; cardialgia; burning heat in the epigastric region; pains of the stomach; abdominal colics; inflation; copious stools; syncope; small, contracted and accelerated pulse; skin cold, sometimes intensely hot; breathing difficult; vertigo, loss of sense, convulsive movements; very painful cramps in the legs; prostration of strength,—death.
Sometimes to the above symptoms is joined a great difficulty of swallowing; deglutition may be suspended for some time. The vomiting and alvine evacuations do not always take place, the necessary consequence of which is an increase in the violence of the other symptoms.
Antidotes.
The great indication to be fulfilled in a case of this description, is the ejection of the salt by vomiting. MM. Orfila and Berthollet rely very confidently upon the effects of bark, strong tea, infusion of galls, and other vegetable astringents, which have undoubtedly the power of decomposing the salt. They ought, therefore, to be employed as diluents to assist vomiting, but they are not to be considered as antidotes which can render this latter operation less indispensable.
Physiological action of emetic tartar.
M. Majendie has shewn by experiment, that if tartarized antimony be injected into the veins of a dog, the animal vomits, and has frequent stools; his breathing becomes difficult; his pulse frequent and intermitting; a great degree of disquietude, and tremblings are the precursory signs of death, which generally takes place within the first hour from the injection of the emetic tartar. On opening the body great alterations are perceived in the lungs; they are found of an orange or violet colour, have no crackling, are distended with blood, and of a tight texture. The mucous membrane of the intestinal canal, from the cardia to the extremity of the rectum is red, and strongly injected.
If, instead of thus injecting the emetic tartar into the veins, it be injected into the stomach, and the œsophagus is tied to prevent vomiting, M. Orfila informs us that the same alterations will be found after death. The very same effects will also arise from the application of the emetic tartar to the different absorbing surfaces, such as the cellular substances, &c.
Mr. Brodie[[304]] has also thrown considerable light upon the action of this salt. He observes that the effects of emetic tartar so much resemble those of arsenic, which we have already described, and those of muriate of baryta, which will form a future subject of inquiry, that it would be needless to enter into a detail of the individual experiments which he made with it. When applied to a wound in animals which are capable of vomiting, it usually, but not constantly, operated very speedily as an emetic; in other respects he found no material difference in the symptoms produced in the different species of animals, which he had been in the habit of employing as subjects of experiment. The symptoms were paralysis, drowsiness, and, at last, complete insensibility; the pulse became feeble, but the heart continued to act after apparent death, and was maintained in action by means of artificial respiration; but never for a longer period than for a few minutes. Whence it would appear, that this poison acts by being absorbed, and that it directs a sedative influence upon the heart, as well as the brain, but that its principal action is on the latter. The length of time which elapses, from the application of the poison to the death of the animal, varies; in some instances Mr. Brodie found that it did not exceed three quarters of an hour, but in others, it was two or three hours, or even longer, before death took place. When a solution of emetic tartar was injected into the stomach of a rabbit, Mr. Brodie observed the same symptoms to take place, as when it was applied to a wound.
Organic lesions discovered by dissection.
Mr. Brodie, in his examination of animals poisoned by emetic tartar, sometimes found the stomach bearing the marks of inflammation, but at other times, its appearance was perfectly natural. In no case did he discover any traces of inflammation in the intestines. The reader must compare this account with that already given by M. Majendie, at p. [282].
1. Tests for the detection of emetic tartar.
1. The poison is in a solid form. Dissolve a portion of the suspected salt in about fifteen times its weight of boiling distilled water; if it be emetic tartar, the following reagents will identify it, viz.
(a) The hydrosulphurets will occasion a reddish-yellow precipitate, which is a combination of oxygen and antimony, proceeding from the emetic tartar; and of hydrogen and sulphur, from the reagent employed. If it be dried on a filter, and mixed with charcoal and the potass of commerce, it gives, by the action of heat, a cake of metallic antimony.
(b) Tincture of galls. This is regarded as the most sensible test of this salt, affording a precipitate of a curdled, dirty white colour, inclining to yellow.
(c) Lime water. This reagent produces a white precipitate, which is extremely thick, and is easily redissolved by pure nitric acid. In this case the lime forms an insoluble tartrate, and the tartrate of antimony, thus rendered insoluble, subsides along with it.
(d) Concentrated sulphuric acid gives a white precipitate, which consists of the oxide of antimony retaining a small portion of the acid. It redissolves in an excess of the precipitant.
(e) Vegetable extractive, occasions in the solution of this salt, a reddish-yellow precipitate, which has been found to consist of oxide of antimony, and a portion of vegetable matter.
2. It is mixed with various alimentary substances.
If our attempts should fail to procure a solution of the salt by filtration, answering to the above reagents, we must rely upon the proof of metallic reproduction. Various circumstances may invalidate the action of our tests, such, for instance, as the ingestion of some vegetable infusion or decoction, especially that of galls, or yellow bark.
With respect to the other preparations of antimony, it is unnecessary to waste our time in their consideration; the precepts already given will afford the practitioner every requisite hint for the prosecution of the enquiry.
Copper.
This metal, with the exception of gold and silver, and perhaps tin, was known earlier than any other metal; but its applications were entirely confined to the arts. It was first discovered by the Greeks in the island of Cyprus, whence its name; and we learn from Homer, that even during the Trojan war, the combatants had no other armour but what was made of bronze, which is a mixture of copper and tin.[[305]].
The external characters of the metal are too well known to require minute description. Its taste is styptic and nauseous; and the hands when rubbed for some time on it, acquire a peculiar and disagreeable odour. When melted, its specific gravity is 8·667; but after being hammered it is 8·9. It is only susceptible of two degrees of oxidation. If the protoxide be native, it is red; if artificial, orange coloured. The peroxide is black.
Copper, on exposure to a moist atmosphere, becomes tarnished, absorbs a portion of its oxygen, and passes into the state of an oxide, which shortly unites with the carbonic acid of the atmosphere, and forms a greenish carbonate of copper.
Metallic copper, perfectly pure, does not possess any deleterious properties. We have already cited instances[[306]] sufficiently conclusive to establish this fact. It becomes, therefore, a subject of no little interest to enquire, under what circumstances it may become poisonous by combination. M. Orfila observes that it has been long maintained, that milk heated, or allowed to remain in vessels of copper not oxidized, dissolved a portion of this metal, and acted as a poison. Eller, a philosopher of Berlin, has, however, very clearly proved such an opinion to be incorrect. He boiled in succession, in a kettle well freed from verdegris, milk, tea, coffee, beer, and rain water; after two hours boiling, he found it impossible to discover, in any of these fluids, the least vestige of copper. M. Drouard has also shewn that distilled water, left for a month together on the filings of this metal in a glass bottle, did not dissolve an atom of it. The celebrated toxicologist above cited, after relating these important facts, concludes by observing, that the phenomena are very different, if, instead of pure water, we substitute that which contains a certain quantity of muriate of soda. Eller has demonstrated the presence of a very small quantity of copper in water, which contained 1/20th of its weight of muriate of soda, and which had been boiled in a brass kettle. This fact is of the highest importance, for it will explain the reason why highly seasoned aliments have proved deleterious, when cooked in vessels of copper. But we are indebted to Mr. Eller for a still more important discovery; he found that if, instead of heating a simple solution of common salt in copper vessels, the salt be previously mixed with beef, bacon, and fish, the fluid resulting from it does not contain an atom of copper.[[307]] In relating this fact, M. Orfila observes, “however astonishing it may appear, it is quite correct, M. Eller was the first to announce it, and I have several times ascertained the truth of it; it is probable,” continues Orfila, “that the combination of several kinds of aliments destroys the effect of the solution of the muriate of soda; which consequently ought to render the cases of poisoning by aliments cooked in copper vessels, which are not oxidized, extremely rare.”
Copper combines with sulphur, and affords a black sulphuret.
Oxide of Copper.
By oxidation, copper becomes poisonous. The substance may be easily recognised by the change of colour which it produces in ammonia; this alkali will dissolve it instantly, and assume a beautiful blue colour. It is wholly insoluble[[308]] in water. In oils and fatty matter it is easily and copiously dissolved at the ordinary temperature of the atmosphere. Such bodies also, when boiled in vessels of perfectly clean copper, facilitate their oxidation, especially if left to cool a few minutes before they are poured out.
Green Carbonate of Copper—Natural Verdegris.
This substance forms spontaneously on surfaces of copper and brass; it differs from the oxide in its green colour, and in effervescing with dilute sulphuric acid; with ammonia, however, it demeans itself in the same manner, and is likewise insoluble in water. It is poisonous.
From the above history of these substances the medical practitioner will easily perceive under what circumstances, and by what bodies, metallic vessels of copper may be rendered dangerous. The oxide and carbonate, formed in them, will easily dissolve in acidulous and oily aliments, whence it follows that all preparations of such food, if conducted in vessels whose surfaces have contracted this change will be liable to prove deleterious.[[309]] If the vessels be perfectly clean, acid preparations may be safely boiled in them, but they must be poured out immediately, and not suffered to remain sufficiently long to allow the copper to become oxidized. To the formation of the oxide of copper, and to the acetic acid contained in the wine, vinegar, beer, and cider, M. Orfila attributes the production of the acetate which forms about the corners of the cocks in vessels containing these liquors. Upon the same principle the soda water sold in this town, in a draught, from the pump, is liable to metallic impregnation, as we have fully satisfied ourselves.
Equally important is it for the forensic physician to be acquainted with the various other sources from which copper poison may be derived. In consequence of the fact of the oxide of copper forming, with the acids, compounds of a beautiful green colour, the metal is often employed in cookery to impart a vivid hue to various articles; the sale of pickles, for instance, frequently depends upon the liveliness of their green colour; whence we find, in works[[310]] on cookery, directions for ensuring such an effect, by boiling the pickles with copper coin, or by suffering them to stand for some time in vessels of that metal. In the third volume of the Medical Transactions of the College of Physicians we shall find an interesting history, related by Dr. Percival of Manchester, of a young lady who amused herself, whilst under the hands of the hair-dresser, with eating pickled samphire, of which she consumed two breakfast plates full; she shortly afterwards complained of great thirst, pain in the stomach, and a rash appeared upon her hands and breast. After an illness of nine days, during which she suffered severe vomitings, and tormina of the bowels, she expired. Upon examining the samphire, Dr. Percival found that it was very strongly impregnated with copper. In the preparation of confectionary, especially sugar-plums, and sweatmeats of a green colour, copper is very generally introduced, and many instances are recorded of their having proved highly deleterious. Catsup is also said to be occasionally impregnated with verdegris; and vestiges of this metal have been detected in the well known cordial, called Shrub.
In order to prevent the contingent dangers attendant upon copper vessels, they ought always to be tinned;[[311]] and it is a very curious and interesting fact, that this latter metal, although it may cover the copper surface only imperfectly, will nevertheless protect us from its effects; for M. Proust has shewn that the superior readiness with which tin is oxidized and acted upon by acids, when compared with copper, will not allow this latter metal to appropriate to itself a single atom of oxygen.
But copper vessels, notwithstanding this fact, unless well tinned, should be dismissed from the service of the kitchen. The Senate of Sweden, in the year 1753, prohibited them entirely, and ordered that none but such as were made of iron should be used in their fleets and army.
Verdegris. Ærugo.
The verdegris of commerce is a compound mass, consisting of the acetate, and sub-acetate of copper, carbonate of copper, and copper partly metallic, and partly oxidized; it, moreover, contains the stalks of grapes and other extraneous matter. Boiling water dissolves it in part, and, at the same time, occasions in it a chemical change, by transforming one portion of the sub-acetate into the soluble acetate, and another, into an oxide of copper, which is precipitated. With cold water, verdegris demeans itself very differently; the acetate is dissolved by it, whilst that portion which is in the state of sub-salt remains suspended in the form of a fine green powder. Vinegar converts all the ærugo into a soluble acetate. Sulphuric acid poured on its powder decomposes it with effervescence, and vapours of acetic acid are disengaged; a character by which this substance may be easily identified.
Blue Vitriol. Sulphate of Copper.
Blue Copperas—Roman Vitriol.
This salt occurs in crystals of a deep rich blue colour, and whose form is that of a rhomboidal prism; their taste is harsh, acrid, and styptic; on exposure to air they slightly effloresce, and assume a greenish hue. When treated with sulphuric acid, no effervescence occurs, a circumstance which at once distinguishes this salt from ærugo.
Symptoms of Poisoning by the Salts of Copper.
The operation of these bodies, upon the human system, is betrayed by an acrid, styptic, coppery taste, in the mouth; nausea; head-ache; a dry and parched tongue; vomiting; coppery eructations; a cutaneous eruption; violent pains in the bowels; very frequent alvine evacuations, sometimes green, and often bloody and blackish; great and painful distention of the abdomen; small and irregular pulse; heat of skin; ardent thirst; difficult and laborious respiration; hiccup; syncope; cold sweats; convulsions—death. It does not, however, kill so speedily as arsenic, or corrosive sublimate.
Organic Lesions discovered on Dissection.
Where death has been speedily produced by a cupreous poison, dissection will generally discover inflammation, and even gangrene in the mucous membrane of the alimentary canal. Like other poisons of the corrosive class it will also be found to have occasionally extended its inflammatory action to all the coats of the canal, producing sloughs, easily detached, and leaving perforations. Dr. Male has also remarked that inflammation will sometimes be observed in the brain; but that this is not an universal effect of copper poison. It has been stated, that the fluids contained in the primæ viæ are, upon these occasions, very frequently tinged with a green colour.
Chemical Tests by which the presence of the preparations of Copper may be detected.
1. The suspected body is in a solid form.—We have already pointed out the characters by which the principal preparations of copper may be identified. Our judgment, however, upon these occasions will require that confirmation from experiment, which the following processes are calculated to afford.
A. By its reduction to a metallic state. If the copper presents itself in the form of an oxide, it may be easily reduced by heating it, in the usual manner, in contact with some carbonaceous matter; an earthen crucible will furnish the most convenient vessel for the occasion. If the substance has been scraped from a surface of copper, it is probably in the state of carbonate, (natural verdegris,) and may be calcined with charcoal in order to procure the metal. Should the substance in question be true ærugo, we may at once heat it to redness in an earthen crucible, when, without the aid of any carbonaceous matter, we shall obtain metallic copper.
B. By the application of certain reagents, or tests, to its solutions.
It may happen that the quantity of the above substances is not sufficient to allow their metallic reduction by calcination. In that case, we must proceed to obtain a solution; but since neither the oxide, nor the carbonate, is soluble in water, it will be necessary to bring them in contact with concentrated acetic acid, so as to obtain an acetate of copper; which will furnish the following indications with the respective tests.
a. A surface of clean iron. If dipped into the solution will become coated with metallic copper, and appear as if transmuted into that metal.
b. Ammonia. This test, when added in a quantity more than sufficient to saturate any excess of acid, will strike a beautiful blue colour; in the first instance we shall obtain a deep blue precipitate, but this will be redissolved by an excess of alkali. To detect the presence of copper, therefore, in pickles, it is only necessary to cut them into small pieces, and to pour liquid ammonia, diluted with an equal bulk of water, over them in a stopped phial: if the pickles contain the most minute quantity of this metal, the ammonia will assume a blue colour. In the same manner cupreous impregnations may be discovered in the various articles of confectionary above enumerated, and in those foreign conserves which are imported into this country, and usually sold in round boxes.
c. Sub-carbonate of Potass. By this re-agent a precipitate of a pale blue colour is produced.
d. Arsenite of Potass instantly occasions a copious precipitate in the acetate of copper, which is of a green colour, and is in fact an arsenite of the metal.
e. Triple Prussiate of Potass. This test gives a brown precipitate with a solution of verdegris, which is found to consist of prussiate of copper, and prussiate of iron; while the liquor contains an acetate of potass.
2. The suspected poison is mixed and combined with various alimentary substances.
We have in this case the same embarrassments to encounter, as those already noticed under the consideration of arsenic. Our tests may produce their respective precipitates, but they will present different colours according to the nature of the fluids with which the substance happens to be mixed; whence the circumstance of colour, so characteristic on other occasions, cannot be received as a satisfactory indication. In such a difficulty, we may collect the precipitates, and calcine them in a crucible with charcoal, in order to obtain the metal; or we may at once evaporate the whole of the alimentary mass, and submit it to a high temperature, by which means all the vegetable and animal principles, which can form a part of the liquor vomited, will be decomposed and converted into several volatile productions, and into charcoal; this combustible body will decompose the oxide of copper, and reduce it to its metallic state.[[312]].
Nor is this process without its fallacies; it is often difficult to recognise the metal, dispersed as it necessarily must be, in small quantity, through a considerable mass of charcoal; in this case we are recommended by Orfila to place the product of the calcination in water, when in a short period, the copper, from its superior specific gravity will subside from the lighter particles of charcoal. But it would be still better to pour nitric acid upon the product of the calcination, and thereby to obtain a solution of nitrate of copper, which by filtration might be immediately prepared for the application of appropriate re-agents.
It merits notice, however, that in certain cases of poisoning by copper, no vestiges of the substance can be found in the matters voided from the stomach. In that case, Orfila directs that the mucous membrane of the stomach, and of the intestines, should be scraped off, dried, and submitted to the action of a strong heat in a crucible. “I have,” says this distinguished experimentalist, “twice obtained metallic copper, by calcining in this manner a portion of the membranes of the stomach of two dogs that I had poisoned with verdegris. This effect particularly takes place when the mucous membrane is of a bluish colour, hard, and strongly adhering to the substance of the stomach.”
Tin and its Muriate.
It is clearly established by the experiments of Bayen and Charlard,[[313]] as well as by those of Proust,[[314]] that this metal possesses no poisonous properties. Its muriate, however, has been shewn by Orfila to possess highly corrosive properties. It excites violent vomiting, great depression, and death, without convulsions. Its antidote is milk, which it speedily coagulates; and by chemical combination with it, the poison is rendered inert. On dissection, the stomach is said to have been found corrugated and indurated, and has been compared to tanned skin, but its colour is not altered.
As this substance is never likely to become an object of forensic interest, in this kingdom, we shall pass it over without farther notice.
Zinc.
The ancients were acquainted with a mineral to which they gave the name of Cadmia,[[315]] from Cadmus, who first taught the Greeks to use it. They knew that when melted with copper it formed brass; and that when burnt, a white spongy kind of ashes was volatilized, which they used in medicine.[[316]] This mineral contained a good deal of zinc; and yet there is no proof remaining that the ancients were acquainted with that metal. It has a brilliant white colour, with a shade of blue, and is composed of a number of thin plates adhering together; its specific gravity is 7·1. When strongly heated in a crucible, it quickly goes into fusion, absorbs the oxygen of the atmosphere, and burns with a beautiful white flame, inclining to green, and extremely brilliant. The oxide of zinc thus formed, is diffused through the atmosphere, and is there condensed into extremely light flakes of a beautiful white appearance. This oxide was formerly known under the fanciful names of nihil album; lana philosophorum, &c.
In its metallic state it is quite inert; but late experiments by Vauquelin and Deyeux, have proved that it is very easily acted upon by water, the weakest vegetable acids, some saline substances, and butter; a fact which is hostile to the proposal of employing this metal for the manufacture of culinary utensils.
White Vitriol. Sulphate of Zinc.
This salt occurs in masses, consisting of crystals which are four-sided prisms, terminated by four-sided pyramids. Their taste is styptic, metallic, and slightly acidulous. They are soluble in 2·5 times their weight of water at 60°, and in less than their own weight of boiling water, but they are quite insoluble in alcohol. Thus dissolved they redden the tincture of tournesol.
Symptoms of Poisoning by Sulphate of Zinc.
This salt, like tartarized antimony, from the high degree of emetic virtue which it possesses, generally proves its own antidote; still, however, it must be considered as a poison; for several cases are on record, where the most alarming symptoms, and indeed death itself, have been the effect of its ingestion. Metzger[[317]] mentions the case of a woman, who accidentally ate a trifling quantity of a cake, into which White Vitriol had been introduced for the purpose of shortening the days of an old man. The woman died; but the intended victim escaped, after severe vomiting. M. Orfila has also related several cases of poisoning by this salt. The symptoms which presented themselves on these occasions were, an astringent metalline taste, a sense of constriction in the fauces, so distressing as even to excite in the patient a fear of suffocation; frequent vomitings; copious stools; pains in the epigastric region, extending afterwards over the whole abdomen; difficulty of breathing; frequency of pulse; paleness of the countenance, and coldness of the extremities.
We have lately heard of a case in which a noble lord swallowed a solution of white vitriol, which had been sent to him by mistake, for Epsom salts, to which it bears some analogy. Fortunately, however, the violent emetic effect which followed removed the poison from the stomach, and obviated any farther injury.
Organic lesions discovered on Dissection.
We have no well authenticated dissection of a human being who had died from the ingestion of this poison. The examination of animals[[318]] who have been so killed has shewn nothing more than an inflammation, not very severe, of the membrane with which it had come in contact; sometimes dark blood is observed to be extravasated upon the muscular coat of the stomach and intestines.
Chemical processes for the detection of Sulphate of Zinc.
The chemist must remember that the White Vitriol of commerce always contains sulphate of iron, and sometimes sulphate of copper. When dissolved in distilled water it may be identified by the following re-agents; viz.
a. Potass, and Ammonia, precipitate an oxide of a greenish white colour, easily soluble in an excess of the latter of these alkalies. The oxide obtained by potass, being washed and dried, and calcined with charcoal, is revived, provided the temperature be very much elevated. It should be known, that if the salt has been previously purified, the above tests will occasion a white precipitate.
b. Prussiate of Potass produces a precipitate of a rather deep blue colour; which, consists of a mixture of the prussiates of zinc and iron. If the salt has been divested of all impurity, the precipitate will be white.
c. The Hydro-sulphurets instantly occasion a blackish precipitate, which, like the former, will be found to be a mixture of zinc and iron, in the state of an hydro-sulphuret. If the salt, however, is pure, its colour will be white with a tinge of yellow.
Silver.
This metal does not exert any influence on the living body; but its oxide in combination with nitric acid constitutes one of the most corrosive of all the metallic salts.
Lunar Caustic. Nitrate of Silver.
Lapis Infernalis.
The usual state in which this substance occurs is in that of small cylinders, having been cast into moulds for the purpose of imparting to it a form best adapted for the purposes it is designed to answer.
Its action on animal matter is highly caustic, and when introduced in any considerable quantity into the stomach, will induce death by corroding the texture with which it may come in contact. At the same time there is reason to believe that the whole, or part of its composition, may be absorbed; for we have many instances on record where the frequent repetition of this metallic salt, in small doses, has imparted a blue tinge to the skin, which can only be explained on the supposition that the oxide of the metal has been actually deposited in the rete mucosum[[319]].
We are not aware that there is any modern case of poisoning by this salt[[320]]. The medical practitioner, however, ought to know, that common salt, is its true antidote; indeed so completely does it decompose and separate it from water, that if a saturated solution of nitrate of silver be filtered through common salt, it may be afterwards drunk with impunity. M. Orfila, by a series of experiments, has shewn that if the muriate of soda be administered a very short time after the ingestion of lunar caustic, it will disarm it of its virulence by transforming it into an insoluble muriate, possessing no power of acting on the animal œconomy.
Chemical processes for the detection of Lunar Caustic.
If a small portion of the salt can be procured it may be dissolved in distilled water, and immediately identified by the following tests.
a. Muriatic acid, or any soluble Muriate, will precipitate the muriate of silver, which is white, curdled, very heavy, insoluble in water, or nitric acid; but soluble in liquor ammoniæ; when exposed to the air it acquires a black colour.
b. Potass, Soda, and Lime water, will occasion a precipitate of the oxide, of a deep brown colour.
c. Ammonia. This alkali will form an ammoniuret of silver, and in consequence of the solubility of this new product, little or no disturbance is occasioned by the test.
d. Arsenite of Potass. As all re-agents must be considered as reciprocal in their operation, it is hardly necessary to state that this is one of the best tests for nitrate of silver. See the history of its effects at p. [240].
If it should be necessary to discover the nitrate of silver amongst the fluids vomited, or those contained in the stomach of the deceased, we are very properly directed by M. Orfila to filter, and then assay by the appropriate tests; if, however, the different aliments should disguise the characteristic colour and appearance of these precipitates, we must proceed to desiccate and calcine them in order to obtain the silver in a metallic state.
The Concentrated Acids.
These must be regarded as the most terrible of all corrosive poisons. Their action is so immediate and energetic, as generally to destroy the membranes of the stomach, before their peculiar antidotes can be applied. Notwithstanding the obvious suffering they must occasion, and the facility with which they may be detected, such bodies have frequently, especially in France, been the instruments of suicide and murder; whilst in this country, we have had many lamentable illustrations of their deadly force, by their ingestion from fatal carelessness. In conformity with our general plan we shall proceed to consider the individual substances included under this general class, although the symptoms do not materially differ in the different kinds, nor are the indications of cure peculiar to any of them. There are however chemical characters which exclusively belong to each acid, with which the forensic physician must be accurately acquainted, in order that he may be enabled to detect their presence.
Oil of Vitriol. Sulphuric Acid.
This acid, when perfectly pure, exists in the form of a colourless liquid, without smell, and of an oily consistence; whence its popular name. Its specific gravity is 1·85, so that, in round numbers, it may be stated that an ounce, by measure, will weigh fourteen drachms. It acquires a brown tinge from the smallest portion of carbonaceous matter; mere exposure to the atmosphere is sufficient to effect this change, in consequence of the acid disorganizing and carbonating the vegetable and animal matter suspended in the air. This fact sufficiently explains why we generally find the acid of commerce of a brown colour.
Its taste is highly acid and caustic. So powerful is its affinity for water, that upon its admixture with this fluid, a heat, sufficiently great to boil water, may be produced. When exposed in its concentrated state to the air, it will imbibe at least seven times its own weight of water, and so rapidly as to have its weight doubled in a month. Straw, wood, and all vegetable substances, when immersed in the sulphuric acid, without heat, are disorganized, softened, and blackened, and there is separated from them a certain portion of charcoal. Like the other mineral acids, the Oil of Vitriol has never been obtained in an insulated state without water; according to the latest views of Sir H. Davy, the composition of the strongest acid may be expressed as follows. Sulphur 30, oxygen 45, water 17.
Symptoms of Poisoning by Oil of Vitriol.
An extremely austere, acid, and burning taste; a painful heat in the fauces and throat, along the œsophagus, and in the stomach; excruciating pain; nausea, and excessive vomiting; at one time the fluid vomited is as black as ink, at another reddened by arterial or venous blood, producing in its passage through the throat, the most intense pain, accompanied with a sensation of bitterness quite intolerable; if, by chance, a portion of it should fall on the hearth or pavement, or on any other calcareous substance, it will denote its true nature by an effervescence; constipation, or sometimes bloody stools; gripes and excruciating pains over the abdomen, with a tenderness of these regions, so exquisite as not to allow the slightest pressure without torment; pains of the breast; difficulty of breathing; extreme anxiety; the pulse becomes frequent, small, contracted, and irregular; shiverings; great restlessness, dejection, and agitation; convulsive motions of the countenance; sometimes a cutaneous eruption betrays itself. Amidst all these symptoms, the intellectual powers remain unobscured. The parts about the fauces, the uvula, &c. having lost their vitality, slough, and become detached, which occasion an indescribable fetor of the breath, while they produce a perpetual cough, and the voice becomes so altered, that it resembles the sounds of a person labouring under croup.
Organic lesions discovered on Dissection.
As this substance destroys life by simply acting as an escharotic, it is not difficult to anticipate the disorganization which dissection will display. The extent of the lesion, however, must in every case depend upon the quantity and degree of concentration of the acid, the state of the stomach in relation to its alimentary contents, and other incidental circumstances not to be exactly appreciated. The mucous membrane of the mouth, the tongue, and œsophagus, will in general be found destroyed, and converted into a pulp.
Antidotes.
The great indications to be fulfilled in this distressing case, is the immediate dilution, saturation, and expulsion of the poison. Copious draughts of water, holding calcined[[321]] magnesia in suspension, should be administered without any loss of time. If this is not in readiness, soap and water should be administered; mucilaginous drinks, milk, and even warm or cold water, in the absence of more eligible potations, should not be neglected. It must be never forgotten, exclaims Orfila, that success upon these occasions depends upon the activity of the practitioner; the delay of a few moments will entirely change the fate of the patient, as the sulphuric acid destroys the texture of the organs with a fearful celerity. After having thus neutralized the caustic, it will be our duty to obviate the effects it may be likely to occasion; the lancet must be used with boldness, and the detraction of blood repeated at short intervals; at the same time emollient clysters may be advantageously injected.
Chemical processes for the detection of Oil of Vitriol.
In the pure state, there can exist no difficulty in identifying it; its specific gravity, and its action on vegetable matter, will, without any other tests, be quite sufficient to fulfil our object. If heated with metallic mercury, it will disengage sulphurous acid gas; and if united with lime, a sulphate of lime will be produced, which the chemist may easily recognise by dissolving a portion in distilled water, and assaying the solution by muriate of baryta, which will produce with the sulphate a precipitate, insoluble in nitric acid. By the last mentioned tests we shall be enabled to detect the presence of sulphuric acid, in whatever state of complication it may happen to exist with alimentary matter.
Nitric Acid.
This acid, when pure, assumes the form of a limpid fluid, emitting white fumes of a suffocating odour; its taste is highly acid, and corrosive; and it is at once distinguished from all other acids, by its tinging the skin indelibly yellow. When of the specific gravity 1·5 it contains 74·895 per cent of dry acid, (whose ultimate elements are one proportional of nitrogen, and five of oxygen) the complement 25·105 parts, is water.[[322]] It is decomposed with violent action by all combustibles, and when mixed with volatile oils it causes their inflammation.
From the facility with which this acid undergoes decomposition, it is rarely found in commerce in a colourless condition; indeed the action of light is sufficient to impart a tawny tinge to it; when this change has proceeded to such an extent as to render the acid orange coloured, it is called Nitrous acid, or, in the language of the arts, aqua fortis, although in a chemical point of view, such a nomenclature is incorrect, for it is nothing more than nitric acid, holding nitrous acid gas loosely combined.
Symptoms of Poisoning by Nitric Acid.
This acid has been so frequently swallowed in France, for the purpose of committing suicide, that it has enabled the pathologists of that country to afford a very satisfactory account of its operation, and effects. To M. Tartra we are particularly indebted for a very full and interesting investigation of the subject, and we shall avail ourselves upon the present occasion, of the many facts and observations with which his treatise[[323]] abounds. In describing the symptoms occasioned by the ingestion of this acid, M. Tartra establishes four different gradations, viz. 1. When the death is speedy, for it is never sudden, it commonly takes place from the primary effects in about twenty-four hours, varying from six to forty-eight hours. 2. When it proves fatal from its secondary effects, at different intervals, from fifteen days to several years. 3. When death does not take place, but the recovery is imperfect. 4. When a perfect cure is sooner or later obtained. The first case is illustrated by the following example, which will serve to convey a very just idea of the progress and intensity of the symptoms. “A man, driven by distress to commit suicide, under the greatest agitation of mind, and upon an empty stomach, swallowed, at a draught, two ounces of concentrated nitric acid. Instantly he was seized with the most excruciating pains and agitation, and could not lie in bed, but rolled himself upon the floor. Vomiting came on, accompanied by a general sensation of coldness, especially in the extremities. Every time he vomited, the matter effervesced upon the pavement. A solution of soap and oil was administered to him, and in two hours he was brought to the hospital, often having vomited, and stopped on the road to drink. On his arrival, he had emollient drinks, especially linseed tea, in great abundance. He was in continual agitation, and his countenance was greatly altered. He now vomited every instant a blackish glairy matter; he opened his mouth easily, and his tongue was white, with a tinge of yellow; he complained of acute pains in his mouth, along the œsophagus, and in his stomach. His belly, slightly tense, could not bear the slightest pressure, without great torment. The surface of the body was cold; the pulse small and frequent; he had hiccup, and the respiration was laborious.
His symptoms increased. He uttered sighs and lamentations; his limbs became icy; a cold sweat covered his whole body; his pulse was scarcely perceptible; the pain was constant; still he could rise and make continual but useless efforts to quench his thirst, and satisfy his urgent desire to void urine, and go to stool. He continued in this state during the night; the matters vomited became more clear, and of a yellow colour. He at last made a few drops of urine. The shocking appearance of his body already resembled that of a corpse, but he retained his senses, and was speaking when he expired, nineteen hours after swallowing the acid.” The burning heat and pains which are commonly the immediate effects of the ingestion of this acid are very variable in their intensity and duration, and M. Tartra observes that, in general, they are not in proportion to the quantity or strength of the acid swallowed. It often happens that persons who have taken only a small dose, are seized with the most excruciating and dreadful pains, and some of those who have swallowed a great quantity, two or three ounces for example, have had scarcely any suffering, but remained very tranquil. In the first case, the patients either recover, or survive a long time; in the second, speedy death is almost always the consequence; thus a young man of twenty died in twenty hours, without any agitation or signs of acute pains. On opening the body, the highest degree of disorganization appeared, perforations of the stomach, and great effusion of its contents into the abdomen. The second variety of the progress and termination of poisoning by nitric acid, exhibits, at first, the same phenomena as the preceding; but less alarming symptoms succeed by degrees; after some months, the inner membrane of the alimentary canal detaches itself in portions, the patient falls into a marasmus, and dies. We are here presented with a case of consecutive poisoning, see page [147].
The third termination is in imperfect recovery. A slow and progressive amendment ensures the safety of the patient; but there still remains some complaint; obscure pains in the throat, and especially in the epigastric region; habitual constipation, occasional vomiting, and increased sensibility of the stomach, so that it can only support light nourishment and bland liquors; in short, they continue invalids during the rest of their lives; they are subject to repeated and even habitual indispositions, and sometimes to pain and insupportable heat of the stomach; but they are able to follow their occupations, and long survive their poisoning.
The total disappearance of the symptoms produced by swallowing nitric acid; or complete and absolute recovery without leaving any consequences, is the last variety of termination.
Organic lesions discovered on Dissection.
Tartra has furnished us with the following interesting account of the dissection of those who have died of the primary effects of nitric acid. The external appearance of the body presents no alteration; every part is sound and natural, and possesses, in a certain degree, the firmness and freshness of life. The epidermis of the margins of the lips has commonly an orange colour, more or less deep. It seems burnt and easily separates. Sometimes yellow spots are discovered on the hands and other parts of the body, caused by the contact of the acid. A yellow fluid, in some cases very abundant, flows from the mouth and nostrils, and the belly is considerably distended with air. The alimentary canal is remarkably affected. All the internal membrane of the mouth is burnt, and has sometimes a white colour, but is more commonly yellow; it is separate in some places, and adheres in others. The teeth are often loose, and have a very marked yellow colour at their crown. The mucous membrane of the pharynx exhibits the same change, or is in a state of inflammation of a dirty red colour. The whole extent of the œsophagus is lined with a dense mass of a fine yellow colour, dry on its surface, unctuous and greasy to the touch, and which seems to be formed both of the mucous membrane, altered in a particular manner, and of the albumen contained in the viscid fluid which exudes from the membrane of the œsophagus, solidified by the nitric acid. This lining adheres in very few points, and is easily detected from the other membranes of the œsophagus, which are brown and blood-shot. When the stomach is not perforated, it has commonly a considerable size; externally, its membranes are slightly and partially inflamed, but very much towards the pylorus and beginning of the duodenum. Its colour is faded, livid, of a yellowish green, with large gangrenous spots. It adheres every where to the neighbouring parts, the diaphragm, liver, spleen, and transverse arch of the colon, by means of a concrete lymphatic exudation; its sides, which are thin and yellow in some places, and thick and black in others, exhibit net-work of dilated blood-vessels filled with black coagulated blood. Often there are several points of the stomach dissolved, and ready to burst with the slightest touch; it contains a great quantity of gas, which has a peculiar smell, resembling that of bitter almonds; it also very commonly contains a great quantity of yellow matter, of a pultaceous consistence; the substance of the stomach is generally swelled in some places, and deeply marked with black, without being dissolved; this effect is most remarkable at the great end, into which the acid seems to fall by its weight; the rugæ of the stomach are very brown, and are reduced to a mucilaginous consistence. The other parts of the alimentary canal exhibit the same organic lesions, although the phenomena have less intensity in proportion as the part is more distant from the stomach.
In those cases where the stomach is found perforated, its bulk is very small; the holes commonly occur in the large and small extremities; their form is circular, and their edges thin, and as if dissolved. The urinary bladder contains no urine, although the patient have not discharged any.
The appearances upon dissection of those who die of the secondary effects are entirely different from those above described. It would be difficult to find an example of greater emaciation, more advanced consumption, or more disgusting form. Nothing is equal to the degree of withering, and decrepitude of the whole organs; their colour is faded; the internal cavities do not contain the usual serum; the cellular and muscular systems are almost annihilated; the bones become dry, as in persons of advanced age, and break with extraordinary facility; but these changes are general and secondary, and depend upon local organic derangement of the alimentary tube. The stomach and whole intestinal canal are contracted to an extremely small size; the intestines are not larger than the little finger, sometimes not exceeding a thick writing quill; their coats are very thick, their cavity almost obliterated, and containing only a little mucosity. The stomach, which often resembles a portion of a small intestine, appears sound externally, and only presents some adhesions to the neighbouring viscera; internally, the most remarkable change is the contraction of the pylorus, the passage through which will scarcely admit a probe; and the membranes of the stomach itself are so thickened and compacted around it, that they have lost all their natural suppleness. On the internal surface, there are irregular spots, or rather smooth and red places, which seem to be covered with a regenerated mucous membrane, less villous than that which had been destroyed by the action of the acid; these cicatrices are particularly large and numerous in the great end of the stomach, and around the circumference of the pylorus.
Chemical processes by which the presence of Nitric Acid may be discovered.
If the acid be in any quantity, and without mixture, there cannot exist any difficulty in demonstrating its presence. If added to copper filings, there will be a copious disengagement of orange-coloured fumes, and a nitrate of copper of a blue colour will remain, as the product. If it be saturated with potass, we shall at once obtain by due evaporation the well known substance, nitre; this salt will announce its nature by deflagrating with charcoal or sulphur. This latter test is the one we must employ for the detection of nitric acid, when mixed with vinegar, and other liquids. Where the acid has combined with the animal matters with which it may have come into contact, they must be boiled for an hour in a solution of pure potass, when the solution will assume a reddish appearance; this must be filtered, and evaporated in a capsule of porcelain, when the mass so obtained will leave a residuum of nitrate of potass.
Dr. Marcet, in a paper just published in the Philosophical Transactions,[[324]] on the composition of sea water, employed a new mode of assaying the solution for nitric acid, and for which he acknowledges himself indebted to Dr. Wollaston. Having concentrated the bittern in a glass vessel, until it began to deposit solid matter, he added sulphuric acid and gold leaf, and boiled the mixture; the gold leaf was not in the least acted upon, nor was any smell of nitric acid perceived; but on adding the smallest quantity of nitre to the same mixture, the gold was dissolved, and the smell of aqua regia instantly perceived. The rationale of the experiment is obvious, gold, although insoluble in muriatic acid, is instantly dissolved on the addition of nitric acid, in consequence of the developement of chlorine.
Spirit of Salt. Muriatic Acid.
The liquid acid, of which we are about to treat, is a solution of muriatic acid gas in water; when of the specific gravity 1·16, according to Davy, it contains 32·32 per cent. of the gas, which recent experiments have proved to be a compound of Chlorine (oxy-muriatic acid) and hydrogen, in equal volumes. It has accordingly received a name expressive of its composition, and is called Hydro-chloric acid. Its odour is strong and peculiar; when exposed to the air it emits white fumes; its taste is intensely sour and caustic; it is, however, the weakest of the three mineral acids, and no remarkable elevation of temperature is produced by dilution. It readily combines with potass, soda, &c. and furnishes a class of salts which may be easily recognised by their characters.
Symptoms of Poisoning by Muriatic Acid.
As the effects of muriatic acid do not differ from those which have been described, as the consequences of poisoning by the other mineral acids, it will be unnecessary to enumerate them. Orfila, however, remarks, that the patients who have swallowed a certain quantity of it, emit, in the first moments of the accident, a thick smoke of a white colour, and very pungent smell.
Chemical processes for the detection of Muriatic Acid.
This acid, in its free state, immediately announces its nature by the fumes which it emits. When the acid, however, exists in a more questionable shape, as in the matter vomited by the patient, or in that found in the digestive canal after death, it will be necessary to saturate the liquid part with pure potass, and to boil it for some time, when we shall obtain a fluid, from which the nitrate of silver will throw down a dense precipitate. By evaporation, we shall obtain a crystallized muriate, which may be identified by the following tests: 1, When concentrated sulphuric acid is poured upon it, a brisk effervescence is immediately occasioned, and the muriatic acid is disengaged in the form of white vapours, which are thick, and of an excessively pungent smell. 2, If instead of employing concentrated sulphuric acid, this acid be used in a state of dilution, and the muriate be mixed with some substance which easily yields its oxygen, the muriatic acid will be decomposed, its hydrogen, combining with the oxygen so as to form water, while the chlorine will be disengaged, and by its pungent and peculiar odour at once announce the nature of the acid under examination.
Oxalic Acid. Acid of Sugar.[[325]]
This salt occurs in small crystals, whose form is that of a four sided prism. It is extremely acid to the taste, so that by applying the tongue to one of its crystals, its nature may be immediately discovered. It dissolves in twice its weight of cold, and in an equal weight of hot water; it is also soluble in boiling alcohol which takes up about half its weight; the solutions act powerfully on the vegetable colours, and at once denote their acid properties. On account of the strong resemblance which the crystals of this acid bear to those of sulphate of magnesia, or Epsom salts, many fatal accidents have occurred. We are not aware that it is ever purchased, in retail, for any other purpose than as a detergent, to clean the tops of boots; in the large way, it is an article of extensive trade with the calico printers. Its salts[[326]] are likewise employed for various purposes in the arts.
Amongst the many schemes which have been proposed to secure the public against the possibility of mistaking this acid for Epsom salts, there does not appear to be one which admits of successful application; nor are we able to propose any test of discrimination which is not far inferior in accuracy and convenience, to that which is afforded by the mere taste of the crystal; indeed we cannot understand how so acid a solution can be swallowed, without an immediate discovery.
Symptoms of Poisoning by Oxalic Acid.
From the history of the many cases on record, it appears that this acid produces all the grievous symptoms, which characterise the action of a corrosive poison; its operation upon the stomach is similar to that of any other powerful acid; and dissection displays the same destruction of parts, as that we have already described under the consideration of the mineral acids.
Antidotes.
We should endeavour to form as quickly as possible an insoluble oxalate of lime; copious draughts of lime water, or magnesia and water, should be administered; and vomiting immediately excited.
Chemical tests for the detection of Oxalic Acid.
If any of its crystals can be obtained, we shall be immediately able to identify them. They dissolve very readily in water, and since the oxalic has a greater affinity for lime, than any other acid, and forms an insoluble salt with it, we have thus a ready test of its presence, for it will decompose all the calcareous salts, not even excepting the sulphate.
Boiling Water.
Many cases are recorded of the death of children from the ingestion of boiling water; an accident which will be always liable to occur, as long as the peasant allows his family to quench their thirst by drinking the cold water through the spout of the tea kettle. It has been very generally supposed that fatal effects have, on these occasions, supervened the high state of inflammation produced in the æsophagus and stomach by the boiling liquid. Dr. Marshall Hall has, however, lately published a very interesting paper on this subject, in the twelfth volume of the Medico-Chirurgical Transactions; from which it would appear, that the patient, under these circumstances, actually dies of suffocation as in croup; and that the boiling water is arrested in its progress to the stomach by the convulsive action of the muscles of the pharynx. In passing, however, to the posterior part of the mouth, it scalds the epiglottis, and glottis, which afterwards become more and more swollen, until at length the rima glottidis, or orifice into the larynx, becomes completely obstructed. Here then we have a new instance in which the operation of laryngotomy, or of tracheotomy, may be performed with the effect of preventing impending suffocation, and perhaps of saving life. Dr. Marshall Hall relates four cases in illustration of this interesting fact; of which one recovered from imminent suffocation immediately after screaming[[327]]; two died from suffocation, one 10, the other 17 hours, after the accident; the fourth was completely relieved by the operation of tracheotomy, and survived 34 hours, but died, exhausted by the irritation produced by the primary affection.
Melted Lead.
An instance stands recorded in the history of the destruction of the Eddystone-light house, by fire, where a quantity of melted lead fell into the mouth, and was swallowed by a person who was attentively watching the conflagration. It is very singular, that this man lived many days after the accident; a fact which at least shews what extensive injury the stomach will occasionally sustain, without the immediate destruction of life. The lead taken out of the stomach after death, in this case, weighed exactly seven ounces, five drachms, and eighteen grains.[[328]]
The Caustic Alkalies.
These bodies are distinguished by a highly corrosive and peculiar taste; they change the blue[[329]] juices of vegetables to a green, and the yellow to a brown; they are soluble in water, and have the power of imparting the same property to oils, by combining with them, and thus forming saponaceous compounds. With the different acids they constitute peculiar salts. When applied to the flesh of animals they act as powerful caustics, destroying its texture, and ultimately dissolving it; they are accordingly arranged with great propriety under the head of corrosive poisons.
There are three[[330]] alkalies—potass, soda, and ammonia. To the two former the epithet fixed has been applied, since they require a very high temperature for their sublimation; while to the third, that of volatile has been assigned, because, when uncombined, it exists in a state of gas. Potass, as it was considered the product of vegetation, has received the name of the vegetable alkali, while soda, as the base of rock salt, has been distinguished by that of mineral alkali. The distinctions, however, originally established by Avicenna, must now be abandoned, for they have not the slightest foundation in truth; potass, so far from being the exclusive product of vegetation, exists as a constituent part of the Granite, which forms the foundation of our globe; it has also been discovered in the Pumice stone; in some minerals of the Zeolite family; in the Leucite; in the aluminous ores of La Tolfa, &c. and, although potass is undoubtedly procured by lixiviation from the ashes of burnt wood, and other vegetable substances, yet there is ample grounds for supposing that the living plant receives it from the soil in which it vegetates.
Potass, or Potash—
Liquor Potassæ—Potassa Fusa, or Kali Causticum—Lapis Infernalis—Causticum commune acerrimum. Potassa cum Calce—Potassæ Sub-carbonas, or Salt of Tartar—Potash—Pearl ash.
Potass is rarely met with in a pure form, except in the laboratory of the philosophical chemist, and is therefore not likely to become an object of judicial enquiry; but in various states of mixture, as presented in the different preparations above enumerated, it may become the accidental, as well as criminal means of poisoning; we shall therefore consider the chemical history of these different preparations separately, and then describe the symptoms which they generally occasion.
Liquor Potassæ.
This may be considered as a nearly pure solution of potass, although, as it is usually prepared, it contains small portions of muriate and sulphate of potass, silica, and lime. It is a limpid, dense, colourless solution; when rubbed between the fingers it feels soapy, in consequence of a partial solution of the cuticle. As it constitutes a medicine in common use, and, moreover, forms the basis of many quack medicines, as well as of those preparations which are sold under the name of Depilatories, it may readily become the accidental instrument of mischief.
Chemical Tests for its detection.
There cannot exist any difficulty in this investigation; its highly alkaline characters will be immediately announced by its effects on the vegetable test papers, and by its power of saturating acids; while the particular species of alkali may be readily identified by the following reagents.
(a) Carbonic acid; or water saturated with the gas. This will not produce any[[331]] disturbance in the solution of potass; a fact which at once serves to distinguish this alkali from the earths, baryta and lime.
(b) Deuto-muriate of Platina occasions a canary-yellow precipitate, consisting of the deutoxide of platina, potass, and muriatic acid; as this precipitate is, to a certain extent, soluble in water, the test may fail through dilution. With soda, this reagent will not occasion any precipitate, a fact which depends upon the solubility of the triple salt formed, and affords an easy method of distinguishing the fixed alkalies from each other.
(c) Tartaric acid. If an excess of this acid be added, we shall obtain crystals of a bi-tartrate; a phenomenon which will not take place if soda be the alkali employed.
Potassa Fusa, or Kali Causticum.
This substance, which occurs in sticks, or cylinders, is an extremely caustic and deliquescent substance; it is principally employed in surgery, to establish an ulcer; or, instead of incision, to open a tumour. See Pharmacologia. As it differs from potass, only in the degree of purity, it is unnecessary to offer any farther remarks.
Potassa cum Calce.
This is a mixture of the preceding substance with lime, which is added with a view to diminish the deliquescent property of the alkali, and thus to render it more manageable as an escharotic. There will be no difficulty in separating these ingredients. Their different solubilities will furnish an easy mode of effecting it to a certain extent, and we may then precipitate the remaining portion of lime, by carbonic acid.
Sub-carbonate of Potass—Salt of Tartar—Pearl-ash—Potash.
Although potass becomes comparatively mild, by its union with carbonic acid; yet the present preparation retains so much causticity as to render it poisonous, if administered in any considerable dose. Plenck reports a case of this kind, where a patient having swallowed an ounce of salt of tartar, was shortly afterwards seized with a violent vomiting, which continued for forty-eight hours, followed by a violent inflammation of the stomach; from which, however, he ultimately recovered.
Symptoms of Poisoning by any of the above preparations of Potass.
A styptic, urinous, and caustic taste; a severe heat in the throat; violent vomiting, generally of alkaline matter, turning the syrups of violets green, and where the alkali has been in the state of carbonate, effervescing with acids; sometimes the matter thus ejected is mixed with blood; copious alvine evacuations; severe pain in the epigastric region; excruciating tormina of the bowels; depravation of the intellectual faculties, and death. It will be easily perceived that the above symptoms merely indicate the operation of a corrosive poison. They offer no characteristic peculiarities which can enable us to decide upon the particular substance that has been swallowed, unless, indeed, the matter vomited can be submitted to examination.
Antidotes.
From the experiments of Orfila, it appears that vinegar, diluted with water, is the remedy which can be administered with the greatest success, where any preparation of this alkali has been swallowed in a poisonous dose.
Organic lesions discovered on dissection.
In consequence of the peculiar action of this alkali upon animal matter, we shall generally find the stomach perforated, and its coats extensively dissolved. We shall moreover discover the usual indications of violent inflammation in this viscus, as well as in the intestines.
Soda.
We have already stated by what chemical reagents this alkali may be distinguished from potass; it only remains for us to observe that its physiological action, the symptoms arising from its ingestion, and the organic lesions discovered on dissection, are strictly analogous to those we have described as the effects of potass.
Ammonia, and its Carbonate.
Ammonia, in its uncombined state, exists in the state of gas, and is incapable of application; its affinity, however, for water, enables it to combine with that fluid, and to form liquid ammonia, (Liquor Ammoniæ) in which state it is useful in medicine, and in the arts. This solution is colourless; its taste extremely caustic; and its odour strong, pungent, and peculiar. Exposed to the action of heat, the ammoniacal gas is driven off, and may be recognised by its characteristic odour, as well as by its effects upon moistened turmeric paper. When brought into contact with muriatic acid, it will form dense white vapours, consisting of muriate of ammonia. A most elegant and sensible test for ammoniacal gas is afforded by a mixed solution, consisting of arsenious acid and nitrate of silver; these substances when mixed in solution do not occasion the least disturbance in each other, for reasons already explained, (see page [240]) but upon spreading a portion of the liquid upon glass or paper, and bringing ammoniacal gas into contact, a beautiful yellow cloud immediately diffuses itself over the surface of the solution.
Sub-carbonate of ammonia occurs in solid, white, semi-transparent masses, of a highly pungent and ammoniacal odour. Its chemical composition has been found to vary materially according to the circumstances under which it has been prepared; Mr. R. Phillips, who has made some highly interesting experiments upon this subject, considers the sub-carbonate to be a sesqui-carbonate, composed of 3 atoms of carbonic acid, 2 atoms of ammonia, and 2 of water. By long exposure to the air, its pungency is lost, and it is converted into an inodorous carbonate.
Symptoms of poisoning by Ammonia.
Cases wherein death has been produced in a few minutes, from the ingestion of liquid ammonia, stand recorded on the authority of Martinet, Huxham, Haller, and other physiologists. In such cases the lips, tongue, and fauces are described as being burnt by the causticity of the fluid; while hemorrhage of the intestines marks the organic lesions which it occasions. The nervous system would appear also to suffer greatly, at the same time that the abdominal organs are affected with violent inflammation.
The Caustic Alkaline Earths.
Under this division, we have to consider the two earths, Lime and Baryta; both of which are highly corrosive, although they essentially differ from each other in their physiological action. In this respect they may be compared to corrosive sublimate and arsenic, and offer an additional illustration of the imperfection of the present classification; for while lime acts as a local caustic upon the parts with which it comes in contact, baryta will require, for its action, to be absorbed and carried into the current of the circulation.
Quick Lime.
This earth is of a white colour, and of a hot caustic taste; with acids it forms peculiar salts; a fact which we shall shew affords the most decisive means of identifying its presence. It changes vegetable blues to a green, and reddens turmeric; it is capable of fusion; so great is its affinity for water, that it will absorb and solidify one third of its weight of that fluid, and yet remain perfectly dry. The heat, therefore, that is evolved in the process of slacking lime, evidently proceeds from the water, which yields its caloric, as it passes from the liquid to the solid state.
Symptoms of poisoning by Lime.
It is perhaps the least energetic of the corrosive poisons; and yet, when taken in any quantity, it will produce nausea, vomiting, colics, frequent stools, and all the symptoms which characterise, or are complicated with, inflammation of the stomach and intestines.[[332]] Lime in combination with carbonic acid is not considered as poisonous.
Organic lesions discovered on dissection.
In examining the body of an animal that has been killed by caustic lime, we shall find the mucous membrane of the stomach reddened, and evincing marks of inflammation in those parts which have been in contact with it.
Tests for the detection of Quick-lime.
We may proceed, if the substance be free from mixture, to obtain a solution of the earth in distilled water, and to assay it by the following reagents.
(a) Carbonic acid, and the soluble alkaline sub-carbonates produce a copious white precipitate, which is soluble in an excess of carbonic acid. The carbonate of lime, of which this precipitate consists, is also decomposed by muriatic acid, with effervescence, a soluble muriate remaining.
(b) Oxalic acid, and oxalate of ammonia. They precipitate lime-water of a white colour, and the resulting oxalate is not soluble in an excess of acid.
(c) Sulphuric acid. This acid does not precipitate lime water, since the sulphate of lime formed does not require more than 300 parts of water to dissolve it. Whereas, says M. Orfila, the smallest quantity of an exceedingly diluted solution of baryta becomes instantly turbid on the addition of that acid, because the sulphate of baryta is insoluble in several thousand times its weight of water. By this test, therefore, we are at once enabled to distinguish lime-water, from barytic water.
Baryta, and its Salts.
Baryta, like lime, is a solid, heavy, alkaline earth, having an acrid and peculiar taste; and turning the syrup of violets green, and the juice of turmeric red. When perfectly calcined, it absorbs water very rapidly, disengaging at the same time a quantity of caloric; the phenomenon is similar to that of slacking lime, and admits of the same explanation. It dissolves in about 20 parts of water, at the temperature of 60°; but boiling water will dissolve half its weight of this earth, part of which will crystallize on cooling.
Muriate of Baryta. This salt crystallises in square plates, or four-sided prisms; its taste is acrid and pungent. It dissolves in 2½ parts of distilled water at 60° Fah. The solution is limpid and colourless, and has been employed in medicine, as a remedy in scrofula, cancer, some forms of syphilis, and in hectic fever connected with ulceration. Dr. Johnstone says that he has seen a delicate female take as much as thirty drops of a saturated solution of this salt, repeatedly, without nausea; whence he concludes that it would require at least 2 or 3 drachms to do mischief.[[333]]
Symptoms of poisoning by Baryta.
All the soluble compounds of this earth are poisonous, especially the muriate; which, whether injected into the veins, introduced into the stomach, or externally applied to an abraded surface, will occasion death in a very short period. We are not aware that any case stands recorded of poisoning by baryta. Orfila[[334]] and Brodie[[335]] have, however, investigated the symptoms which this poison produces on animals, and they appear to be analogous to those occasioned by the ingestion of arsenic. The muriate, on account of its greater solubility, would appear to be much more active than the pure earth, or its carbonate.
Physiological action of Baryta.
Barytic poisons require to be absorbed before they act on the system; they may therefore destroy by external application, although it would appear that, unlike arsenic, they act sooner when internally administered. Mr. Brodie thinks that the muriate of baryta occasions death by acting upon the brain and the heart; at the same time it exerts a local action, and corrodes the viscus with which it comes into contact.
Antidotes.
It has been shewn by the experiments of Orfila, that the soluble sulphates, as Glauber or Epsom salts, by converting the baryta into an insoluble sulphate, will act as antidotes to its virulence. In the first instance, therefore, it will be prudent to produce this chemical decomposition in the poison, and then to expel it, as quickly as possible, by emetics.
Chemical tests for the detection of Baryta.
Where the pure earth, baryta, or its solution in water, is presented for our investigation, it may be identified by the following reagents.
(a) Sulphuric acid, and the soluble sulphates. These bodies precipitate from the barytic solution, a white sulphate of the earth, insoluble in water, and nitric acid.
(b) Carbonic acid gas, and the alkaline sub-carbonates, produce in it a white carbonate of baryta.
(c) Muriatic acid combines with baryta, and furnishes a salt which is capable of being identified by numerous reagents. M. Orfila has furnished us with the following satisfactory compendium of its habitudes. “A salt which does not redden the tincture of tournesol, which does not turn the syrup of violets green, which is not precipitated by the alkaline hydro-sulphurets,[[336]] nor by ammonia; but which, on the contrary, is precipitated by the sub-carbonate of ammonia, soda, or potass; which is not soluble in concentrated alcohol; which furnishes, with the sulphate of potass, or the sulphuric acid, a white precipitate insoluble in water and in the nitric acid, and which gives with the nitrate of silver a curdled precipitate of muriate of silver, likewise insoluble in the nitric acid, can be no other than the muriate of baryta.”
But it may happen, that the above salt is so mixed with alimentary matter, as to defy the action of the tests; in this case we must endeavour to obtain from it the pure earth, by precipitating the suspected fluids by the sub-carbonate of ammonia; when a carbonate of baryta will fall down, which must be dried on a filter, and calcined with charcoal.
Cantharides. Spanish Flies—Blistering Flies. (Cantharis Vesicatoria, Sp. 1, of Latreille.)[[337]]
Cantharides are imported into this country in their entire state, and are so kept in the shops; their form and general appearance are too well known to require description, and they will rarely become the objects of inquiry; in powder, however, they may be presented to us for investigation, and it is therefore essential that the forensic physician should be acquainted with the appearances which they assume in the state of disintegration. This powder has a greenish colour, tinged with grey, and abounding with shining points of a very beautiful green colour, and which may be recognised in whatever state of division the powder may exist, even after it has passed through a silken sieve. Its odour is acrid and nauseous; when thrown on burning coals it emits that peculiar smell, which generally attends the destruction of animal matter by heat. The chemical history of cantharides is still involved in some obscurity; according to Robiquet, who has furnished us with the most satisfactory analysis, they contain various fatty principles; the phosphates of lime, and magnesia; and the acetic and uric acids; together with a peculiar crystalline principle, in which the vesicatory properties wholly reside, and to which the name of cantharidin has been given by Dr. Thomson.[[338]] It may be obtained in plates, having a micaceous lustre; when perfectly pure it is insoluble in water, but it is rendered soluble in that fluid, by the presence of a yellow matter which exists in native combination with it; it is very soluble in oils.
Symptoms of poisoning by Cantharides.
As this substance forms an article of the materia medica it may become an accidental source of poisoning; whilst a general belief in its aphrodisiac powers may induce a trial of its efficacy, to goad the exertions of exhausted nature, or to incense the passion of females, whose seduction is meditated. In the annals of crime in this country, we are acquainted with but few instances in which cantharides have been given with the view of destroying life; we have already referred[[339]] to the case of Vaux, who was executed for poisoning with cantharides; there is also that of Sir Thomas Overbury, who, on the confession of the person who gave it to him, is said to have taken it, mixed with his sauces. Cantharides may be administered in the form of powder, infusion, or tincture. The following may be considered the more prominent symptoms which will follow the ingestion of a large dose. Violent retching; copious alvine evacuations, frequently bloody; very severe colics; active inflammation of the stomach and intestines; sometimes universal convulsions, attended with a horror of liquids, resembling that which occurs in hydrophobia; furious delirium, &c. But the affections of the urinary passages, and organs of generation, may be regarded, κατεξοχην, as the peculiar symptoms of poisoning by cantharides; such as heat in the bladder, bloody micturition; horrible strangury; painful and obstinate priapism; satyriasis, &c. If the dose has not been sufficient to occasion speedy death, it may produce marasmus.
Organic lesions discovered on dissection.
Where the poison has been administered internally, we shall find the stomach and intestines presenting an appearance of inflammation, very similar to that which we have described as the general result of corrosive poisons. Marks of inflammatory action, and sometimes ulceration, will be also discovered in the urinary and genital organs; especially in those cases where the person dies shortly after the ingestion of the poison.
Methods of detecting the presence of Cantharides.
Where the poison has been administered in substance, we shall generally discover some of its particles mixed with the ejected matter; or, after death, adhering to the coats of the stomach, or to the folds of the intestines, and which may be easily identified by their peculiar green and brilliant hue. If the poison should have been administered in the form of infusion, or tincture, our chemical resources will fail us, and we must rely alone upon the evidence furnished by the symptoms, and organic lesions.
Phosphorus.
This singular substance was accidentally discovered by Brandt, a chemist of Hamburgh, in the year 1669,[[340]] as he was attempting to extract from human urine a liquid capable of converting silver into gold. It was also subsequently discovered by Kunkel and by Boyle, without these latter chemists having, in any way, participated in the researches of each other.
Phosphorus, when pure, is semi-transparent and of a yellowish colour; but when kept some time in water, it becomes opaque externally, and then has a great resemblance to white wax. Its consistence is nearly that of wax; it may be cut with a knife. Its mean specific gravity is 1·770. It generally occurs in sticks. When exposed to the air, provided the temperature be not lower than 43°, it emits a white smoke, which has the smell of garlic, and is luminous in the dark. This smoke is more abundant, the higher the temperature is, and is occasioned by the gradual combustion of the phosphorus. When heated to 148° it takes fire, and burns with a very bright flame, and gives out a great quantity of white smoke, which is phosphoric acid. Oils dissolve phosphorus, provided the temperature be a little raised. Water has no effect upon it, unless it be aerated, when it renders the surface of the phosphorus opaque and white, which in a short time becomes red. This change depends upon oxidation.
Symptoms of poisoning by Phosphorus.
This substance, whether introduced into the stomach in its pure form, or dissolved in oil, will occasion the most violent symptoms, from its escharotic action,[[341]] It has been employed in medicine,[[342]] in a state of minute division, in the dose of one-fourth of a grain, and is said by Leroi to be very efficacious in restoring and establishing the force[[343]] of young persons exhausted by sensual indulgence, and of even prolonging the life of the aged.[[344]] It has also been given as a stimulant in local fevers. We are, however, greatly inclined to question the safety of such a practice, notwithstanding the diminutiveness of the dose. The reader will find some interesting cases of poisoning by phosphorus, translated from the German work of Weickard, in Hooper’s Medical Dictionary, under the consideration of that article. Should such a case present itself for the investigation of the forensic physician, he will not find any difficulty in identifying the substance; its external character, its smell, and, above all, its peculiar property of yielding luminous vapour, are too palpable and distinctive, to admit the possibility of error.
Mechanical Poisons—Powdered glass—Enamel powder—Chopped hair, &c. &c.
We have already examined the pretensions of these bodies to the rank of corrosive poisons, (page [145]) and we should have not reverted to the subject, but from a wish to introduce the account of “a case of Schirrus in the intestines, arising from hairs remaining in the canal,” as related in the Edinburgh Medical Journal,[[345]] by Dr. Burrell, and which had, on the former occasion, escaped our notice. The subject of this history, Laurence Harding, æt. 35, being a private soldier, was admitted into the regimental hospital, for an unrelenting constipation of the bowels; but it appears also that he had been affected with dyspeptic symptoms, and pain in his abdomen, for several years; which pain was aggravated by the ingestion of solid food. He received but little benefit from the remedies that were administered, his strength gradually declined, and, about a month after his admission, he expired.
“On laying open the abdomen, the stomach was found much thickened throughout its whole substance, and the pylorus very much contracted, which contraction continued down the duodenum. Through all the intestines this thickening and gristly appearance was observed. The colon was prodigiously enlarged in its calibre, until where it forms its sigmoid flexure; at which point there were three distinct holes ulcerated through the coats of the intestine, and forming a communication with the abdominal cavity. Beyond the sigmoid flexure the intestine was contracted in its diameter, so as hardly to admit the little finger to pass downwards. On cutting open the pylorus and small intestines, the internal coats were found to be covered with a soft substance, which resembled size. The internal coats of the colon were of a dark colour, and in general were completely ulcerated, and hanging in shreds. The colour of the colon was of a dark lurid red. At the sigmoid flexure there was much contraction, and the thickening was so great on one side, and the valve found so considerable, as hardly to admit a common bougie through it. The portion forming the sigmoid flexure was cut out; and on laying it open, and removing some hardened fæces, five or six hog’s brittles were seen distinctly crossing each other in different directions; they were partially invested in the villous coat, which had grown over them, and which had retained them in the different positions in which they were placed; and so firmly were they kept down by those partial coverings, that it required some force to draw them out. The mesenteric glands were of a cartilaginous appearance; the liver was suffused with blood, and the gall-bladder full of bile. The spleen was very small, and compressed into an oblong shape, probably arising from the pressure of the colon when distended with feculent matter.
This man had formerly been a shoemaker. There was no evidence as to the period at which he swallowed these hairs; but, from the derangement which always existed in the bowels, and the pain referred to the sigmoid flexure, little doubt can be entertained but that these hairs were the cause of all his complaints, and ultimately of his death.”