Читать книгу Treatise on Poisons - Robert Sir Christison - Страница 11

Causes of the disappearance of poison from the body.—Chemical evidence is not always attainable in cases of poisoning. Various causes may remove the poison beyond reach. Hence although poison be not detected in the body,—the experimenter being supposed skilful and the poison of a kind which is easily discovered,—still it must not be concluded from that fact alone that poison has not been the cause of death. For that which was taken into the stomach may have been all discharged by vomiting and purging, or may have been all absorbed, or decomposed; and that which has been absorbed into the system may have been all discharged by the excretions.

1. It may have been discharged by vomiting and purging. Thus on the trial of George Thom for poisoning the Mitchells, held at Aberdeen at the Autumn Circuit of 1821, it was clearly proved, that the deceased had died of poisoning by arsenic; yet by a careful analysis none could be detected in the stomach or its contents; for the man lived seven days, and during all that time laboured under frequent vomiting.^[85] In a remarkable case related by Dr. Roget, arsenic could not be found in the matter vomited twenty-four hours after it had been swallowed;^[86] in another related by Professor Wagner of Berlin, that of an infant who died in twelve hours under incessant vomiting after receiving a small quantity of arsenic, none could be detected in the stomach;^[87] in another which I have described in a paper on arsenic, although the person lived only five hours, the whole arsenic which could be detected in the tissues and contents of the stomach did not exceed a fifteenth part of a grain;^[88] in an American Journal there is a striking case of a grocer, who died eight hours after swallowing an ounce of arsenic, and in whose body none could be found chemically,—at a period however antecedent to the late improvements in analysis;^[89] and in a case communicated to me not long ago by Mr. Hewson of Lincoln, where arsenic was given in solution, and death ensued in five hours, none of the poison could be detected either in the contents or tissues of the stomach by a careful analysis conducted according to the most modern principles.

Nevertheless, it is singular how ineffectual vomiting proves in expelling some poisons from the stomach. Those which are not easily soluble, and have been taken in a state of minute division, may remain adhering to the villous coat, notwithstanding repeated and violent efforts to dislodge them by vomiting. Many instances to this effect have occurred in the instance of arsenic. Metzger has related a case, where, after six hours of incessant vomiting, three drachms were found in the stomach.^[90] Mr. Sidey, a surgeon of this city, has mentioned to me an instance of poisoning with king’s yellow, in which he found the stomach lined with the poison, although the patient had vomited for thirty hours. In three cases which I have investigated arsenic was detected, although the people lived and vomited much for nearly two days;^[91] and Professor Orfila has noticed a similar instance in which that poison was found in the contents of the stomach, although the person had vomited incessantly for two entire days.^[92]

It is not easy to specify the period after which a poison that has excited vomiting need not be looked for in the stomach. It must vary with a variety of circumstances whose combined effect it is almost impossible to appreciate, such as the solubility and state of division of the poison, the frequency of vomiting, the substances taken as remedies, and the like. When the poison is in solution and the patient vomits much, an analysis may be expected to prove frequently abortive, even though the individual survives but a few hours, as in Mr. Hewson’s case already noticed. In other circumstances, however, as various facts quoted above will show, poisons may frequently be found after two days incessant vomiting; and on the whole it may be stated, that the recent improvements in analysis render the period much longer than it has generally been, and would naturally be imagined. Metzger has related the case of a woman poisoned with arsenic mixed with currants, in whose body, after eight days of frequent vomiting, he found ten or twelve currants, which gave out an odour of garlic when burnt;^[93] but here the dose, if there was really arsenic, must have been repeated recently before death, for it is not possible to conceive how currants could remain in the stomach so long, whatever may be thought of the possibility of arsenic remaining. It is farther proper to add, that Professor Henke of Erlangen, one of the highest living authorities in Germany, once found grains of arsenic in the gullet, although he found none in any other part of the body, of a person who survived the taking of the poison four days.^[94] Allowing to this fact all the weight derived from the high name of its author, I must nevertheless express great doubt whether the arsenic was not repeated more recently before death.

2. The poison may have disappeared, because it has been all absorbed. It has several times happened that in the bodies of those poisoned with laudanum, or even with solid opium, none of the drug could be detected after death. Sometimes indeed it is found, even though the individual survived the taking of the poison many hours. Thus a case related by Meyer of Berlin, in which the person lived ten hours after taking the saffron-tincture of opium; and nevertheless it was detected in the stomach by a mixed smell of saffron and opium.^[95] But more commonly it all disappears, unless the dose has been very large. In a case of poisoning with laudanum, which I examined here along with Sir W. Newbigging in 1823, none could be detected, although strong moral circumstances left no doubt that laudanum had been swallowed seven or eight hours before death. An instance of the same kind has been minutely related by Pyl. It was that of an infant who was poisoned with a mixture of opium and hyoscyamus, and in whose stomach and intestines none could be detected by the smell.^[96] Similar observations have been often made on animals; and several additional cases of the same purport, occurring in man, will be related under the head of opium.

It might be of use to quote some of the numerous errors committed by medical witnesses, in consequence of having overlooked the effect of absorption in removing poisons beyond the reach of chemical analysis. But not to be too prolix, I shall be content with mentioning a single very distinct case in point, which happened at a Coroner’s Inquest in London, in 1823. A young man one evening called his fellow-lodger to his bedside; assured him he had taken laudanum, and should be dead by the morrow; and desired him to carry his last farewell to his mother and his mistress. His companion thought he was shamming; but next morning the unfortunate youth was found in the agonies of death. The moral evidence was not very satisfactory; but that is of little consequence to my present object. The point in the case I would particularly refer to is the declaration of the medical inspector, that laudanum could not have been taken, because he did not find any by the smell or by chemical analysis in the contents of the stomach.^[97]

3. Poisons may not be found, because the excess has been decomposed.

Vegetable and animal poisons may be altogether destroyed by the process of digestion. This observation will explain why sometimes no poison could be found in cases of poisoning with crude opium or other vegetable solids. A French physician, M. Desruelles, has related the case of a soldier, who died six hours and a half after swallowing two drachms of solid opium, and in whose stomach nothing was found but a yellowish fluid, quite destitute of the smell of the drug.^[98]

Some mineral poisons, such as corrosive sublimate, lunar caustic, and hydrochlorate of tin, are also decomposed in the stomach. But they are not removed beyond the reach of chemical analysis. The decomposition is the result of a chemical, not of a vital process; and the basis of the poison may be found in the solid contents of the stomach under some other compound form. Other poisons again may be apt to elude detection by altering their form, by combining with other substances, without themselves undergoing decomposition. Thus it appears from a case related by Mertzdorff of Berlin, that, in poisoning with sulphuric acid, after the greater part of the poison is discharged by vomiting, the remainder may escape discovery by being neutralized: For, although he could not find any free acid in the contents of the stomach, he discovered 4½ grains in union with ammonia by precipitation with muriate of baryta.^[99]

It may be also right to mention another kind of decomposition which may render it impossible to detect a poison that has been really swallowed—namely, that arising from decay of the body. In several recent cases bodies have been disinterred and examined for poison months or even years after death. In these and similar cases it would be unreasonable to expect always to find the poison, even though it existed in the stomach immediately after death. Some poisons, such as oxalic acid, might be dissolved and then exude; others, such as the vegetable narcotics, will undergo putrefaction; and others, such as prussic acid, are partly volatilized, partly decomposed, so as to be undistinguishable in the course of a few days only. The mineral poisons, those at least which are solid, are not liable to be so dissipated or destroyed. Some authors, indeed, have said that arsenic may disappear in consequence of its uniting with hydrogen disengaged during the progress of putrefaction, and so escaping in the form of arseniuretted-hydrogen gas; and they have endeavoured to account in this way for the non-discovery of it in the bodies of the people who had been killed by arsenic, and disinterred for examination many months afterwards.^[100] But the supposition is by no means probable: at least arsenic has been detected in the body fourteen months, nay, even seven years, after interment. For farther details, on this curious topic, the reader may turn to the article Arsenic.

On the whole, the result of the most recent researches is that the effect of the spontaneous decay of dead animal matter in involving poisons in the general decomposition appears to be much less considerable than might be anticipated. For this most important medico-legal fact, the toxicologist is indebted to the experimental inquiries of MM. Orfila and Lesueur.^[101] The poisons tried by them were—sulphuric and nitric acids, arsenic, corrosive sublimate, tartar-emetic, sugar of lead, protomuriate of tin, blue vitriol, verdigris, lunar caustic, muriate of gold, acetate of morphia, muriate of brucia, acetate of strychnia, hydrocyanic acid, opium, and cantharides. They found that after a time the acids become neutralized by the ammonia disengaged during the decay of animal matter;—that by the action of the animal matter the salts of mercury, antimony, copper, tin, gold, silver, and likewise the salts of the vegetable alkaloids, undergo chemical decomposition, in consequence of which the bases become less soluble in water, or altogether insoluble;—that acids may be detected after several years’ interment, not always, however, in the free state;—that the bases of the decomposed metallic salts may also be found after interment for several years;—that arsenic, opium, and cantharides undergo little change after a long interval of time, and are scarcely more difficult to discover in decayed, than in recent animal mixtures;—but that hydrocyanic acid disappears very soon, so as to be undistinguishable in the course of a few days.

4. Lastly, the poison which has been absorbed into the system, and may consequently be detected in certain circumstances in the textures of the body at a distance from the alimentary canal, may also be removed beyond the reach of analysis, by being gradually discharged along with the excretions. It has been fully proved in recent times, that in poisoning with arsenic the poison may be found in ordinary cases, for some days after being swallowed, in the liver especially, but also in the other textures, in the blood, and in the urine; but that if a flow of urine be established and kept up, in nine or ten days, and sometimes much sooner, it can no longer be discovered anywhere by the nicest analysis.^[102]

Is the discovery of poison in the body or the evacuations essential to establish a charge of poisoning? It was mentioned at the commencement of the present section, that the chemical evidence is generally, and correctly, considered the most decisive of all the branches of proof in cases of poisoning. But some toxicologists have even gone so far as to maintain that without chemical evidence, or rather, in more general terms, without the discovery of poison either in the body itself or in the evacuations,—no charge of poisoning ought to be held as proved. This, however, is a doctrine to which I cannot assent. In the preceding observations on the evidence of general poisoning it has been several times alluded to as unsound; and repeated opportunities of establishing exceptions will occur in the course of this work, under the head of individual poisons. At present it may be well to illustrate its unsoundness in reference to those charges of poisoning, where no particular poison is pointed at by the medical evidence, but where a whole class of poisons must be kept more or less in view. Even here I apprehend there may be sufficient evidence in the symptoms and morbid appearances, without any chemical facts,—to render poisoning so highly probable, that in conjunction with strong moral evidence, no sensible man can entertain any doubt on the subject. Several illustrations might be here given; and some will be found scattered throughout the work. In the present place a few instances will be mentioned which cannot be conveniently arranged any where else, and which are well worthy of notice, as being striking examples of the decision of questions of poisoning without chemical evidence.

A man of doubtful character and morals, well acquainted with chemistry and medical jurisprudence, and of disordered finances, was known to harbour a design on a friend’s wife, who possessed a considerable fortune. At last he one morning invited the husband to breakfast with him at a tavern; and they breakfasted, in a private apartment, on beef-steaks, fried potatoes, eels, claret, and rum. They had scarcely commenced the meal when his guest complained of feeling unwell; and soon afterwards he vomited violently. This symptom continued, along with excruciating pain in the belly, for a long time before the prisoner sent for medical aid; indeed he did not procure a physician till the sufferer had been also attacked with very frequent and involuntary purging. The physician, who, before seeing his patient, had received the prisoner’s explanation of the apparent cause of the illness, was led at first to impute the whole to cholera caught by exposure to cold; but on returning at seven in the evening, and finding the gentleman had been dead for an hour, he at once exclaimed that he had been poisoned. On the body being inspected much external lividity was found, contraction of the fingers, and great inflammation of the stomach and intestines, presenting an appearance like that of gangrene.^[103] On analyzing some fluid left in the stomach, no arsenic or other poison could be detected. The attention of the inspectors was turned specially to arsenic, because the prisoner was proved to have bought that poison, and to have made a solution of some white powder in his kitchen not long before the deceased died. The prisoner in his defence stated, that the deceased had been for some time much weakened by the use of mercury, and while in this state was seized with cholera; and he likewise attempted to make it probable that the man, in despair at his not recovering from a venereal disease, might have committed suicide. The council of physicians who were required to give their opinion on the case state on the contrary, that the diseased was a healthy man, without any apparent disposition to disease; that there was no pretext whatever for supposing suicide; that the inflammatory state of the stomach and bowels supplied strong probability of poisoning with arsenic, but not certain evidence; that acute gastritis from natural causes is always attended with constipation; that the deceased presented symptoms of stupor and other signs of derangement of the nervous system remarked in rapid cases of poisoning with arsenic; that cholera is very rare at the end of November, the season when this incident occurred; and that the poison might well be discharged by vomiting. Although all the prisoner’s statements in defence were contradicted by satisfactory proof, and the medical evidence of poisoning was supported by a chain of the strongest general circumstances, the crime was considered by the court as not fully proved, because the prisoner could not be induced to confess, and because poison was not actually detected in the body. But on account of the very strong probability of his guilt, he was, in conformity with the strange practice of German courts in the like cases, condemned to fifteen years’ imprisonment.^[104] In this instance—considering the kind of symptoms, their commencement during a meal, the rapidity of death, the signs of violent inflammation in the stomach after so short an illness, and the facility with which the absence of poison in the contents of the stomach may be accounted for, more especially if it be supposed that the poison was administered in solution,—I consider the medical evidence of death by poisoning so very strong, that, the general evidence being also extremely strong, the prisoner’s guilt was fully demonstrated.

A case of the same kind, but of still greater interest, is that of Mary Anne M’Conkey, who was tried at the Monaghan Assizes in 1841 for the murder of her husband. I am indebted for the particulars to Dr. Geoghegan, one of the principal Crown witnesses. The prisoner who had been too intimate with another man, and had been heard to express her intention of getting rid of her husband, was observed one day before dinner to separate some greens for him from the plateful intended for the rest of the family. None of the latter suffered at all. But her husband was taken violently ill immediately after dinner, and died; and a neighbour accidentally present, who partook, though sparingly, of the same dish with him, was also similarly and violently affected but recovered. The deceased before finishing the greens said they had a disagreeable sharp taste, and was seized soon after with burning at the heart, tenderness at the pit of the stomach, vomiting, coldness, a sense of biting in the tongue and tingling through the whole flesh, excessive restlessness, occasional incoherence, locked-jaw, clenching of the hands, and frothing at the mouth; and he expired three hours after the meal. His neighbour, two minutes after finishing his greens, experienced a sense of pricking in the mouth and burning in the throat, gullet, and stomach; then salivation, a feeling of swelling in the face without actual fulness, general numbness and creeping in the skin; next excessive restlessness, coldness of the integuments, dimness of sight, and stupor; about an hour after the meal he became speechless, repeatedly fainted, frothed at the mouth, and clenched his hands; vomiting ensued, with considerable relief, and subsequently he had frequent attacks of it, with purging, tenderness of the epigastrium, cramps, and tingling in the flesh; and from these symptoms he recovered so slowly as to be unable to work for five weeks. The only morbid appearance of any note in the body of the deceased was a number of irregular brownish-black patches on the inside of the stomach. No poison could be detected in the contents or tissues of the stomach; none could be discovered in the house except a corrosive-sublimate solution which the prisoner used for a gargle; and none could be traced into her possession. A variety of circumstances of a general nature, which are passed over here for brevity, as not strictly appertaining to the present view of the case, threw very great suspicion over the prisoner. The medical witnesses deposed, that poisoning could alone explain the medical circumstances; and Dr. Geoghegan was of opinion that death was owing to some vegetable poison, although he could not specify the particular substance. He suspected, however, that it was monkshood. In these views, when consulted by him before the trial, I entirely concurred. Considering the taste observed by the deceased at the time he ate the greens, the rapidity with which he was taken ill afterwards, and the very peculiar symptoms, unlike those of any natural disease with which physicians are acquainted, and agreeing with those which are produced by monkshood,—considering also that another individual, who partook of the same dish with him, was similarly and simultaneously attacked, and with a severity proportioned to the quantity he took, while other persons who ate the same food from a different dish, did not suffer at all,—it appears to me that poisoning was clearly established; and I also think that the general evidence brought home the charge of administering the poison to the prisoner. She was condemned and executed, and confessed before execution, that she did poison her husband, and that the substance she used was the powdered root of monkshood, which is well known as a poison to the peasantry of Monaghan under the name of Blue Rocket.

It is scarcely necessary to add, that great caution must be observed in applying the general principle here inculcated. But the opposite doctrine, that no charge of poisoning can be established without the discovery of poison in the body or in the evacuations, appears to me a great error, though upheld by no mean authority. Under that doctrine few criminals would be brought to justice, were they to resort to a variety of vegetable poisons, which in certain seasons are within the reach of every one.