Page:Treatise on poisons in relation to medical jurisprudence, physiology, and the practice of physic (IA treatiseonpoison00chriuoft).pdf/478

 on the gullet,—insensibility being then the chief symptom; and that forty grains of the powder killed another dog in four hours and a half, although he was allowed to vomit. In all the instances in which it was administered by the stomach, that organ was found much inflamed after death; and generally fragments of the poison were discernible if it was given in the form of powder. When applied to a wound the powder excites surrounding inflammation; and a drachm will in this way prove fatal in thirty-two hours without any particular constitutional symptom except languor. M. Poumet has since obtained results not materially different.

These experiments do not furnish any satisfactory proof of the absorption of the poison, but rather tend to show that it does not enter the blood. Such a conclusion, however, must not be too hastily drawn; since its well-known effects on man when used in the form of a blister lead to the conclusion that it is absorbed, and that it produces its peculiar effect on the urinary system through the medium of the circulation. On account of the magnitude of the dose required to produce severe effects on animals, Orfila's experiments on the stomach and external surface of the body cannot, for reasons formerly assigned [452] be properly compared together.

The effect of cantharides, when admitted directly into the blood, seems much less than might be expected. Mr. Blake found that an infusion of two drachms injected into the jugular vein of a dog, caused some difficulty of breathing, irregularity of the pulse, and diminished arterial pressure, but apparently no great inconvenience to the animal. The greater effect observed in Orfila's experiment was probably owing to obstruction of the pulmonary capillaries by the oil.

Orfila has examined with care not only the preparations of cantharides already mentioned, but likewise the various principles procured by M. Robiquet during his analysis; and it appears to result, that the active properties of the fly reside partly in the crystalline principle, and partly in a volatile oil, which is the source of its nauseous odour.

The symptoms produced by cantharides in man are more remarkable than those observed in animals. A great number of cases are on record; but few have been minutely related. Sometimes it has been swallowed for the purpose of self-destruction, sometimes for procuring miscarriage. But most frequently, on account of a prevalent notion that it possesses aphrodisiac properties, it has been both voluntarily swallowed and secretly administered, to excite the venereal appetite. That it has this effect in many instances cannot be doubted. But the old stories, which have been the cause of its being so frequently used for the purpose, are many of them fabulous, and all exaggerated. Often no venereal appetite is excited, sometimes even no affection of the urinary or genital organs at all; and the kidneys and bladder may be powerfully affected without the genital organs participating. It is established, too, by frequent observation, that the excitement of the genital organs can never be induced, without other violent constitutional symptoms being also brought on, to the great hazard of life.