Page:Treatise on poisons in relation to medical jurisprudence, physiology, and the practice of physic (IA treatiseonpoison00chriuoft).pdf/578

 are concentrated. It is named hyoscyamia. This substance in its pure state, as first obtained by MM. Geiger and Hesse, is a solid body, in fine silky crystals, without odour, of a strong acrid taste like tobacco, partially volatilizable with boiling water, entirely volatilizable alone at a somewhat higher heat, very soluble in alcohol and ether, but sparingly so in water.

Farther, hyoscyamus, like many other narcotic vegetables, stramonium, digitalis, opium, tobacco, and hemlock, has been found by Mr. Morries Stirling to yield by destructive distillation an empyreumatic oil of great activity. Its poisonous properties, however, are not essential to the oil, but reside in a volatile principle which may be detached by weak acetic acid. The relation of this principle to hyoscyamia has not been ascertained; but it is an active poison, small doses producing in rabbits, convulsions, coma, and speedy death.

Runge proposes as evidence of poisoning with hyoscyamus, in common, however, with stramonium and belladonna, to concentrate a solution of the contents of the stomach, and apply it to a cat's eye to dilate the pupil. Dilatation, he says, was even produced by an extract obtained from the urine of a rabbit which had been fed some time on hyoscyamus.

According to the experiments of Professor Orfila, the juice or extract procured from the leaves, stems, and especially the root, produces in animals a state of sopor much purer than that caused by opium. It is most active when injected into the jugular vein, less so when applied to the cellular tissue, and still less when introduced into the stomach. Except occasional paralysis of the heart, indicated by florid blood in its left cavities, no morbid appearance is to be found in the dead body. Six drachms of the pharmaceutic extract of the leaves killed a dog in two hours and a quarter when swallowed; and three drachms killed another in four hours through a wound in the back. Its action appears to be exerted through the medium of the blood-vessels, and is purely narcotic.

It is probable that the activity of this plant is much affected by season; and the energy of its preparations varies greatly with the manner of obtaining them. The information, however, which is at present possessed on these two points is vague, because the influence of the two circumstances has seldom been viewed carefully apart.

The leaves, from which the pharmaceutic preparations of hyoscyamus are obtained, are commonly held to be most active during the inflorescence of the plant in the second summer of its existence. On general principles this appears probable; but there are no satisfactory experiments on the subject, even the late researches of Mr. Houlton having left much still to be determined.