As this substance forms an article of the materia medica it may become an accidental source of poisoning; whilst a general belief in its aphrodisiac powers may induce a trial of its efficacy, to goad the exertions of exhausted nature, or to incense the passion of females, whose seduction is meditated. In the annals of crime in this country, we are acquainted with but few instances in which cantharides have been given with the view of destroying life; we have already referred[339] to the case of _Vaux_, who was executed for poisoning with cantharides; there is also that of _Sir Thomas Overbury_, who, on the confession of the person who gave it to him, is said to have taken it, mixed with his sauces. Cantharides may be administered in the form of powder, infusion, or tincture. The following may be considered the more prominent symptoms which will follow the ingestion of a large dose. Violent retching; copious alvine evacuations, frequently bloody; very severe colics; active inflammation of the stomach and intestines; sometimes universal convulsions, attended with a horror of liquids, resembling that which occurs in hydrophobia; furious delirium, &c. But the affections of the urinary passages, and organs of generation, may be regarded, κατεξοχην, as the peculiar symptoms of poisoning by cantharides; such as heat in the bladder, bloody micturition; horrible strangury; painful and obstinate priapism; _satyriasis_, &c. If the dose has not been sufficient to occasion speedy death, it may produce marasmus. _Organic lesions discovered on dissection._ Where the poison has been administered internally, we shall find the stomach and intestines presenting an appearance of inflammation, very similar to that which we have described as the general result of corrosive poisons. Marks of inflammatory action, and sometimes ulceration, will be also discovered in the urinary and genital organs; especially in those cases where the person dies shortly after the ingestion of the poison. _Methods of detecting the presence of Cantharides._ Where the poison has been administered in substance, we shall generally discover some of its particles mixed with the ejected matter; or, after death, adhering to the coats of the stomach, or to the folds of the intestines, and which may be easily identified by their peculiar green and brilliant hue. If the poison should have been administered in the form of infusion, or tincture, our chemical resources will fail us, and we must rely alone upon the evidence furnished by the symptoms, and organic lesions. PHOSPHORUS.