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 It is very sparingly soluble in water, but easily soluble in alcohol and the volatile oils. Its alcoholic solution has an alkaline reaction. It forms neutral and crystallizable salts with the acids. In its ordinary form it is turned orange-red by the action of nitric acid; which tint becomes violet-blue on the gradual addition of hydrosulphate of ammonia. The action of nitric acid is owing to the presence of a yellow colouring matter, or of another alkaloid, brucia, which is also contained in nux vomica, but exists in larger quantity in the false angustura bark. Pure strychnia is not turned orange-red by nitric acid.

No poison is endowed with more destructive energy than strychnia. I have killed a dog in two minutes with a sixth part of a grain injected in the form of alcoholic solution into the chest; I have seen a wild-boar killed in the same manner with the third of a grain in ten minutes; and there is little doubt that half a grain thrust into a wound might kill a man in less than a quarter of an hour. It acts in whatever way it is introduced into the system, but most energetically when injected into a vein. The symptoms produced are very uniform and striking. The animal becomes agitated and trembles, and is then seized with stiffness and starting of the limbs. These symptoms increase till at length it is attacked with a fit of violent general spasm, in which the head is bent back, the spine stiffened, the limbs extended and rigid, and the respiration checked by the fixing of the chest. The fit is then succeeded by an interval of calm, during which the senses are quite entire or unnaturally acute. But another paroxysm soon sets in, and then another and another, till at length a fit takes place more violent than any before it; and the animal perishes suffocated. The first symptoms appear in 60 or 90 seconds, when the poison is applied to a wound. When it is injected into the pleura, I have known them begin in 45 seconds, and Pelletier and Caventou have seen them begin in 15 seconds. M. Bouillaud has recently found that it has no effect when directly applied to the nerves. The experiments of Mr. Blake tend to show, that its action is exerted solely on the nervous system, and that it has no direct action on the heart, even when directly admitted into the blood by the jugular vein. It appears to act peculiarly by irritating the spinal cord.

Dangerous effects have often been occasioned by an accidental over-dose in ordinary medical practice. These are well exemplified by a case communicated to Dr. Bardsley by Dr. Booth of Birmingham. A man of 46, affected with hemiplegia for nearly four weeks, began to use strychnia, and had been affected by it for eleven days without particular inconvenience. During this period he took twice a day gradually increasing doses, till the amount of one grain was attained; when the usual physiological effect having ceased to occur,