Van Swieten’s solution of corrosive sublimate was introduced in the middle of the eighteenth century as a remedy for syphilis, and for a long time was highly esteemed. Its author, Baron von Swieten, was of Dutch birth, and was a pupil of Boerhaave. He was invited to Vienna by the Empress Maria Theresa, and exercised an almost despotic authority in medical treatment. His original formula was 24 grains of corrosive sublimate dissolved in two quarts of whisky, a tablespoonful to be taken night and morning, followed by a long draught of barley-water. Corrosive sublimate was the recognised cure for syphilis, at least in Vienna, at that time. Maximilian Locher, another noted physician of the same school, claimed to have cured 4,880 cases in eight years with the drug. This was in 1762. CINNABAR. The bisulphide of mercury (cinnabar) was also used in many nostrums. Paris says it was the active ingredient in Chamberlain’s restorative pills, “the most certain cure for the scrophula, king’s evil, fistula, scurvy, and all impurities of the blood.” “KILLING” MERCURY. The art of extinguishing or “killing” mercury has been discussed and experimented on from the fifteenth century until the present day. The modern use of steam machinery in the manufacture of mercurial ointment, mercurial pills, and mercury with chalk has put a check on the ingenuity of patient pharmacists, who were constantly discovering some new method for accelerating the long labour of triturating, which many operators still living can remember. Venice turpentine, or oil of turpentine, various essential oils, sulphur, the saliva of a person fasting, and rancid fat were among the earlier expedients adopted and subsequently discarded. The turpentines made the ointment irritating, the sulphur formed a compound, and the rancid fat was found to be worse than the turpentines. Nitrate of potash, sulphate of potash, stearic acid, oil of almonds and balsam of Peru, the precipitation of the mercury from its solution in nitric acid, spermaceti, glycerin, and oleate of mercury have been more modern aids. It would be outside the purpose of this sketch to deal with the questions which the numerous processes suggested have raised. Apparently it is not completely settled now whether the pill, the powder, and the ointment depend for their efficiency on any chemical action such as the oxidation of the metal in the cases of the two former, or on a solution in the fat in the case of the ointment. These theories have been held, and do not seem unlikely; but there also seems good reason to believe that mercury in a state of minute division has definite physiological effects by itself. At any rate, it is well established that the more perfectly the quicksilver is “killed” the more efficient is the resulting compound. SILVER.