Tincture of perchloride of iron acquired its reputation in the 18th century from the secret medicines known as La Mothe’s “gouttes d’or,” and Bestucheff’s Nerve Tincture (see page 321). The formula of the latter, published by the Academy of Medicine of St. Petersburg, was corrected by Klaproth, and under various names and in different forms found its way into all the pharmacopœias. Klaproth’s process was to dissolve powdered iron in a mixture of muriatic acid 3, and nitric acid 1; evaporate to dryness, and then leave the mass to deliquesce to a brown liquor. Mix this with twice its weight of sulphuric ether. The saturated ethereal solution to be mixed with twice its volume of spirit of wine, and kept in small bottles exposed to light until the liquid acquired the proper golden tint. A similar preparation is retained in the French Codex under the title of ethereal-alcoholic tincture of muriate of iron. Reduced Iron, or Iron reduced by hydrogen, was first prepared by Theodore Quevenne, chief pharmacist of the Hôpital de la Charité, about the year 1854. Pharmacological experiments were made with it by himself in association with Dr. Miquelard. It was believed at first that the metallic iron obtained by the process described, which was to heat the hydrated oxide of iron in a porcelain tube to dull red, and then to pass a current of hydrogen through the tube, was absolutely pure, and from experiments on dogs they came to the conclusion that the metal in this form was more assimilable than any of its salts. It had besides the advantage of being almost tasteless. Quevenne’s treatise describing the process and the experiments was published in 1854 under the title of “Action physiologique et therapeutique des ferrugineux.” Later investigations, while supporting the original opinion to a great extent as to the assimilability of the reduced iron, established that the product is not and cannot be pure. Dusart showed in 1884 that the proportion of actual iron could not exceed 87 per cent., and was not likely to be more than 84 per cent. Oxides, and carbonates of iron were inevitable, while sulphur, arsenic, phosphorus, and silicon were probable contaminations from the gas. Citrate of Iron in scales was introduced by Beral, of Paris, in 1831. His formula is given in the _Pharm. Jnl._, vol. I, p. 594. Syrup of Phosphate of Iron was introduced in a paper read to the Medical Society of London in 1851 by Dr. Routh, and Mr. Greenish subsequently described to the Pharmaceutical Society the process by which it was prepared. The formula was afterwards improved by Mr. Gale, and his process was adopted in the B.P. It has since been modified.