Two preparations of ZINC must be noticed:

Sulphate of Zinc (White Vitriol, White Copperas.)—This is a very mild irritant, resembling in its appearance Epsom salts and oxalic acid. It is very useful as an emetic in scruple or half-drachm doses, dissolved in any thin fluid.

In one case an ounce was accidentally taken. Great pain in the stomach, vomiting, and prostration, soon set in. Subsequently there was gastritis, and recovery only occurred after a prolonged convalescence.

Treatment.—Vomiting is to be encouraged by milk or albuminous fluids; after which remedies containing tannin (strong tea, decoction of oak bark, or tincture of Peruvian bark) are to be given.

Chloride of Zinc.—A solution of chloride of zinc forms a valuable disinfectant, but is also a dangerous irritant, or, if sufficiently strong, a corrosive poison. Sir William Burnett’s Fluid consists of gr. xxv of this salt to the drachm of water. It has been taken in mistake for fluid magnesia, pale ale, &c., and has caused death.

Symptoms.—A burning sensation in the mouth and throat is immediately produced. This is followed by nausea, vomiting, and signs of collapse. Death has occurred in less than four hours.

Post-mortem Appearances.—The mucous membrane of the throat and stomach has been found corrugated, hard, and leathery. In the case of a sailor who died from about half a pint of Burnett’s solution, the body was livid, the neck swollen, the cerebral vessels were engorged, and the lungs were congested. The mucous coat of the stomach was of a purple red, and partially corroded, while the pyloric orifice looked as if caustic had been applied to it. There were patches of congestion in different parts of the small intestines.

Treatment.—Albuminous drinks, followed by some preparation of tannin, will be needed.

Tests.—Zinc is distinguished from all other substances by giving a white precipitate with sulphuretted hydrogen. The solution containing it must not be too acid or no precipitate will be formed. Zinc also gives white precipitates with ferrocyanide of potassium and ammonia.

Nitrate of Silver (Lunar Caustic).—This is a powerful irritant, and has proved fatal in at least two instances. The antidote is common salt, which must be given immediately, followed by emetics.

Tin.—The chlorides of tin being employed in dyeing, color-making, &c., may lead to their being used as poisons, or being taken accidentally. Death from their use is rare. They are decomposed by magnesia, which should therefore be freely administered, followed by albuminous and mucilaginous drinks.

Bismuth.—The nitrate or magistery of bismuth has caused death in nine days, after a dose of two drachms. The symptoms were those of a strong irritant, but in all probability were caused by some impurity in the substance. Arsenic is frequently present in this way. As no antidote is known, vomiting must be promoted and emollient drinks freely given.

Chrome.—The bichromate of potassium is found in the form of orange-red crystals, which yield a yellow acid solution. It is used as a dye, and has caused death in more than one instance. Emetics and magnesia or chalk, must be the remedies employed.

It is well to know that this substance is apt to produce troublesome sores on the hands of those engaged in its manufacture. Some slight abrasion begins the lesion, which does not heal, but forms on its surface a tough slough, which separating, leaves a foul ulcer with hard edges, and most untractable, behind it.

Sulphate of Iron (Green Vitriol, Copperas).—Although not a powerful irritant, sulphate of iron has proved fatal when taken in a large dose. It is sometimes given to procure abortion. The perchloride of iron has also produced alarming symptoms, after being taken for the same purpose. Dr. Christison relates the case of a man who died in five weeks from an ounce and a half of the tincture. Magnesia and diluents, freely administered, must constitute the treatment.