Читать книгу Treatise on Poisons - Robert Sir Christison - Страница 9

The appearances left in the dead body after death by poison used formerly to be relied on as strongly as the symptoms during life; and with even less reason. Except in the instance of a very few poisons, the morbid appearances alone can never distinguish death by poison from the effects of natural disease, or from some other kinds of violent death. There is not much room, therefore, for general remarks under the present head.

It was at one time thought by the profession, and is still very generally imagined by the vulgar, that unusual blackness or lividity of the skin, indicates death by poison generally. But every experienced physician is now well aware, that excessive lividity is by no means universally produced by poison, and that it is likewise produced by so many natural diseases as not even to form, in any circumstances whatever, the slightest ground of suspicion. Neither is there any difference in kind, as some imagine, between the lividity which succeeds death by poison, and that which follows natural death. Yet it is right for the medical jurist to be aware that lividity as a supposed consequence of poison ought to be strictly attended to by medical inspectors and law officers while investigating charges of poisoning, because the vulgar belief on the subject sometimes leads to such conduct or language on the part of the poisoner as betrays his secret at the time, and constitutes evidence of his guilt afterwards.

Another appearance equally unimportant is early putrefaction of the body. Early putrefaction, at one time much insisted on as a criterion of poisoning,^[78] cannot even justify suspicion. It is by no means invariably, or even generally caused by poisons; nay, sometimes a state precisely the reverse appears to be induced;^[79] and it is seen quite as frequently after natural death.

Some other appearances, not more conclusive, might also be mentioned here; but they belong properly to the effects of individual poisons, or of classes of poisons, not to those of poisoning generally. It may merely be remarked at present, therefore, that the appearances after death, which are really morbid, and which may be produced by poisons, are, in one great class, the signs of inflammation of the alimentary canal in its progressive stages,—in another class, the signs of congestion within the head,—and in a third, a combination of the effects of the two preceding classes; that neither set of appearances is invariably caused by the poisons which usually cause them; that congestion within the head is really seldom produced by those which are currently imagined to produce it; and that most of the appearances of both kinds are exactly similar to those left by many natural diseases.

But although, on the whole, the appearances after death, when considered singly, can seldom supply evidence of poisoning even to the amount of probability, they may nevertheless prove very important under other points of view. Thus, in connection with the symptoms and the general evidence, the appearances after death may furnish decisive proof; and even should the history of the symptoms be unknown, or have been unskilfully collected, the appearances after death, by pointing out the nature of the previous illness, may furnish evidence enough to decide the case, when the moral proof is strong. Again, in cases of alleged imputation of poisoning they are necessary to determine whether a poison actually found in the body was introduced during life or after death. Besides, the very absence of morbid appearances may afford presumptive proof in some circumstances,—when, for example, the question is, whether a person has died of apoplexy or of poisoning with narcotics? Farther, a few poisons, as was formerly stated, occasionally produce appearances so characteristic, as not to be capable of being confounded with the effects of any other agent whatsoever: It will be found hereafter, for example, that the mineral acids have at times left behind them in the dead body unequivocal evidence of their operation. And finally, in cases where no doubt can be entertained that poison was taken, the evidence from morbid appearances may be useful or necessary for settling whether or not it was the cause of death. Two pointed examples of this kind will be noticed under the next section.

When signs of the action of poison are not found in the dead body, and on the contrary marks are found of the operation of natural disease, the presumption of course is that the person died a natural death. But here a few words of caution must be added with regard to the drawing of that inference in cases where the history of the symptoms is not known. It does not follow merely because certain appearances of natural disease are found, that their cause was the cause of death. For death may have arisen from a totally different cause, such as poisoning. This remark is not, as some may imagine, the offspring of hypothetical refinement, but a necessary caution, drawn from actual and not unfrequent occurrences. Thus, for example, the following cases will show, that there may be found in the dead body diseased appearances, arising from pleurisy, hydrothorax, or peripneumony, sufficient to cause death, or to account for death in ordinary circumstances; and that nevertheless the disease may have been completely latent, and death have arisen from poison. In Rust’s Magazin is related the case of a German apothecary, who poisoned himself with prussic acid, and in whose body the lower lobe of the left lung was found consolidated and partly cartilaginous.^[80] In Corvisart’s Journal an army-surgeon has described the case of a soldier, who died of a few hours’ illness, and whose right lung was found after death forming one entire abscess; yet to the very last day of his existence he daily underwent all the fatigues of a military life; and in fact he died of poisoning with hemlock.^[81] In Pyl’s Memoirs and Observations, there is a similar account of a woman who enjoyed tolerable health, and died during a fit of excessive drinking, and in whose body the whole left lung was found one mass of suppuration.^[82] Under the next section will be mentioned other equally pointed cases of death by poison, where the apparent cause of death was external violence.

The conclusions to be drawn from these facts are that, at all events, the medical inspector in a question of poisoning, must take care not to be hurried away by the first striking appearances of natural disease which he may observe, and so be induced to conduct the rest of the inspection superficially; and likewise, that he should not so frame his opinion on the case, as to exclude the possibility of a different cause from the apparent one, unless the appearances are such as must necessarily have been the cause of death. It may be said, that in requiring this condition for an unqualified opinion, a rigour of demonstration is exacted, which can rarely be attained in practice. But, on the one hand, it must not be forgotten, that an unqualified opinion is not always necessary; and on the other hand, although it were, I think it might be shown, if the subject did not lead to disproportionate details, that we may often approach very near the rigour of demonstration required. At present no more need be said, than that the inspector should be particularly on his guard in those cases, in which the appearances, though belonging to the effects of a deadly disease, are trifling; and still more in those in which the appearances, though great, belong to the effects of a disease, whose whole course may be latent. And I may add, that, from what I have observed of medico-legal opinions, the caution now given is strongly called for.

It may be right to allude here also to another purpose which may be served by a careful consideration of the morbid appearances. In cases in which the history of the symptoms is unknown or imperfect the extent and state of progress of the appearances will sometimes supply strong presumptive evidence of the duration of the poisoning. This is an obvious and important application of the knowledge of the pathology of poisoning; but the simple mention of it is all which can be here attempted, as special rules can hardly be laid down on the subject.