Page:Treatise on poisons in relation to medical jurisprudence, physiology, and the practice of physic (IA treatiseonpoison00chriuoft).pdf/289

 caused by arsenic, it must appear that the medical jurist can never be supplied from this source alone with satisfactory evidence of the cause of death. But in some circumstances the evidence may amount to a strong probability of one variety or another of irritant poisoning. Mere redness, conjoined or not with softening of the mucous membrane, may justify suspicion only. But if there should be found in the body of a person who has died of a few days' illness, redness, black warty extravasation, and circumscribed ulcers of the villous coat of the stomach,—effusion of blood or bloody clots among the contents of that organ,—also redness of the intestines, more especially redness and ulceration of the colon and rectum,—and redness of the pharynx, or of this along with the gullet,—the proof of poisoning with some irritant will amount to a strong presumption. At least it is difficult to mention any natural disease which could produce in so short a time such a conjunction of appearances as this; which arsenic and other analogous poisons sometimes occasion.

IV.—On the Treatment of Poisoning with Arsenic.

It was formerly proved that arsenic acts in all its forms of chemical combination, which have been hitherto tried, and nearly in the ratio of their solubility. This general fact is conformable with the law laid down as to the influence of chemical changes on the energy of poisons which enter the blood [p. 37]. Hence every supposed chemical antidote must be useless, which does not render the arsenic insoluble not only in water, but likewise in the contents and secretions of the stomach.

The antidotes chiefly trusted to until recent times, such as vinegar, sugar, butter and other oily substances, lime-water, bitter decoctions, and the like, have now justly fallen into disuse. The liver of sulphur or sulphuret of potassium, which maintained its character for some time longer on account of its chemical action with oxide of arsenic in solution, is not more efficacious. The experiments of Renault on the counterpoisons for arsenic, confirmed by the subsequent researches of Orfila, have proved that the arsenical sulphuret formed by solutions of the liver of sulphur is scarcely less active than the oxide itself.

It appears that fine impalpable powders, though inert as physiological agents, and destitute of any true chemical action with oxide of arsenic, may nevertheless prove useful in certain limited circumstances. Thus Mr. Hume of London and others have apparently found some advantage in the administration of large doses of magnesia. If this substance be of any use at all, which is doubtful, it can act only by covering the arsenical particles with its fine insoluble powder, and so preventing them from coming in contact with the surface of the stomach; for in its state of magnesia it has no chemical action with oxide