CHROMIUM
Two compounds of this metal are largely used in the arts for dyeing purposes—the neutral chromate and the acid bichromate of potash. The bichromate of potash is a powerful poison, and death may occur from its direct action on the nervous system, without the development of any of the signs of irritation; in other cases, however, well-marked irritant symptoms have been present. Applied externally, it produces deep fistulous sores, especially on the mucous membrane of the septum of the nose, in the workmen who are engaged in its manufacture. These sores are prevented to some extent by taking snuff. Dyers not infrequently suffer severely on their arms when using it in the course of their trade. Death has resulted in four hours after its administration.
Chemical Analysis.—A solution of the bichromate of potash, added to a solution of acetate of lead, gives a yellow precipitate; with nitrate of silver, a red. The salt boiled with hydrochloric or sulphuric acid and alcohol, gives a green liquid.
Treatment.—Emetics, magnesia, chalk, demulcent drinks, &c.
CHAPTER V
VEGETABLE AND ANIMAL IRRITANTS
Mode of Action.—The general effects produced by the somewhat large class of vegetable irritants are—
1. Severe abdominal pain, accompanied with vomiting and purging.
2. Absence in most cases of any cerebral or nervous symptoms.
3. The irritant properties appear to reside in an acrid oil or resin. In colchicum, stavesacre, and some others, the presence of an alkaloid may account for their active properties.
4. In medicinal doses, the vegetable irritants act as safe purgatives.
5. The post-mortem appearances found in the alimentary canal betoken inflammation, the result of irritation.
6. Applied externally, they produce inflammation, pustular eruptions, and sometimes unhealthy callous sores.