About 1540 Antoine Lecoque, a physician of Paris, acquired considerable reputation for his cures of syphilis by gold. Fallopius, Hoffmann, and Dr. Pitcairn, of Edinburgh, more or less fully adopted his treatment, but the theory gradually dropped out of medical practice. It was revived early in the nineteenth century by Dr. Chrestien, of Montpellier, a physician of considerable reputation, and his ardent advocacy had for a time considerable effect. But subsequent trials in the French hospitals gave negative results. There were, no doubt, many honest attempts to make aurum potabile, and certainly there were a multitude of frauds palmed off on to a public who had come to believe in the miraculous remedial powers of the precious metal. The following is one of the simplest formulas for extracting the virtue of gold. It is given in “Lewis’s Dispensatory,” 1785, but not with any suggestion of its medicinal value:--One drachm of fine gold was dissolved in 2 ounces of aqua regia. To the solution 1 ounce of essential oil of rosemary was added, and the mixture well shaken. The yellow colour of the acid solution was transferred to the oil, which was decanted off, and diluted with 5 ounces of spirit of wine. The mixture was digested for a month, and then acquired a purple colour. Lewis explains that the oil takes up some of the gold, which, however, is deposited on the sides of the glass, or floats on the surface in the form of a slight film. AURUM FULMINANS was described in the works attributed to Basil Valentine, and later by Oswald Crollius. It is sometimes termed Volatile Gold. Valentine explains very clearly the process of making it, that is, by dissolving gold leaf in aqua regia and precipitating the fulminating gold by salt of tartar. By treatment with vinegar or sulphur its explosive properties were to be reduced. It was supposed to possess the medicinal value of gold in a special degree, and was particularly recommended as a diaphoretic. It appears from reports that it occasioned violent diarrhœas, and was, no doubt, often fatal. The so-called Mosaic Gold, which was given as a remedy for convulsions in children, was an amalgam of mercury with tin, ground with sulphur and sal ammoniac. Hahnemann insisted that gold had great curative powers, and several homœopathic physicians of our time have highly extolled it. Dr. J. C. Burnett, in “Gold as a Remedy,” recommended triturations of gold leaf, one in a million, as a marvellous heart tonic, especially in cases of difficult breathing in old age. IRON.