In a charge of wilful abortion the mere possession of oil of savin would be a suspicious circumstance, because the notion that it has the power of causing miscarriage is very general among the vulgar; while it is scarcely employed by them for any useful purpose. The leaves in the form of infusion are in some parts of England a popular remedy for worms; and the oil is used in regular medicine as an emmenagogue.
The following list includes all the other plants which have been either ascertained experimentally to belong to the present order, or are believed on good general evidence to possess the same or analogous properties.
By careful experiment Orfila has ascertained that the Gratiola officinalis, Rhus radicans and Rhus toxicodendron, Chelidonium majus and Sedum acre, possess them; and the following species are also generally considered acrid, namely, Rhododendron chrysanthum and ferrugineum, Pedicularis palustris, Cyclamen Europæum, Plumbago Europæa, Pastinaca sativa, Lobelia syphilitica and longiflora, Hydrocotyle vulgaris. To these may be added the common elder or Sambucus nigra, the leaves and flowers of which caused in a boy, once a patient of mine, dangerous inflammation of the mucous membrane of the bowels lasting for eight days.
CHAPTER XXI.
OF POISONING WITH CANTHARIDES.
The second group of the present Order of poisons comprehends most of those derived from the animal kingdom. In action they resemble considerably the vegetable acrids, their most characteristic effect being local inflammation; but several of them also induce symptoms of an injury of the nervous system.
This group includes cantharides, poisonous fishes, venomous serpents, and decayed or diseased animal matter.
The first of these is familiarly known as a poison even to the common people. I am not aware that it has ever been used for the purpose of committing murder. But on account of its powerful effect on the organs of generation it has often been given by way of joke, and sometimes taken for the purpose of procuring abortion. Fatal accidents have been the consequence.
The appearance of the fly is well known. When in powder, as generally seen, it has a grayish-green colour, mingled with brilliant green points. It has a nauseous odour and a very acrid burning taste. Alcohol dissolves its active principle. This principle appears from a careful analysis by M. Robiquet to be a white, crystalline, scaly substance, insoluble in water, but soluble in alcohol as well as in oils, and termed cantharidin.[[1482]]
In compound mixtures cantharides may generally be detected by the green colour and metallic brilliancy even of its finest powder, if examined in the sunshine—and sometimes by making an etherial extract of the suspected matter, and producing with this extract the usual effects of a blister on a tender part of the arm. By these two tests Barruel discovered cantharides in chocolate cakes, part of which had been wickedly administered to various individuals.
From the late important researches of M. Poumet[[1483]] it appears, that cantharides cannot be detected by its chemical properties in the contents, or on the inner surface, of the alimentary canal of animals poisoned with it; and that in such circumstances it is seldom to be discerned even by the shining green colour of its particles, unless the matter to be examined be dried. The method he recommends for a medico-legal investigation is to detach the stomach, small intestines, and great intestines, each separately from the body,—to wash out their contents with rectified spirit, and dry the pulpy fluid on sheets of glass,—to dry the stomach and intestines by distending them, removing their mesentery, and hanging them up vertically with a weight attached to stretch them,—and then to examine both the surface of the glass, and the inside of the stomach and intestines with the aid of sunshine or a bright artificial light. In this way cantharides may be detected, by the peculiar green hue of its powder, in most cases where this poison may have proved fatal; for M. Poumet constantly found it in dogs. The same author ascertained that the green particles generally abound most in the contents of the great intestine or on its inner membrane, next in the small intestines, and least of all in the stomach; and that they may be seen in the bodies of animals at least seven months after interment. Orfila had previously ascertained, that cantharides powder may be recognized by its brilliancy in various organic mixtures after interment for nine months.[[1484]] Poumet farther states that the green particles of cantharides may be confounded with the particles of other coleopterous insects, and also somewhat resemble particles of copper and tin. But he with reason asks, what possible accident could introduce the powder of any other coleopterous insect into the alimentary canal? And as to particles of copper or tin, he ascertained, that, unlike cantharides, these substances are visible in the contents, or on the tissues, of the stomach and intestines only before desiccation, and never after it.