The hypophosphites in the form of syrup were introduced by Dr. J. F. Churchill, of Paris, as specifics in consumptive diseases about 1857. His preference of these salts over the phosphates was based on the theory that the deficiency in the system in a phthisical condition was not of phosphates, which had been completely oxidised, but of a phosphide in an oxidisable condition, and this requirement was fulfilled by the hypophosphites. The latter he compared to wood or coal, the phosphates to ashes, so far as active energy was concerned. Dr. Churchill’s interest in a special manufacture of the hypophosphite syrups prejudiced the medical profession against his theories, and it is not certain that he got a fair hearing in consequence. The general verdict was that his results were not obtained by other experimenters, but for a good many years past syrups of the hypophosphites have been among the most popular of our general tonics. Phosphorus is soluble in alcohol, ether, chloroform, bisulphide of carbon, and to a very small extent in water. * * * * * Phosphor paste as a vermin killer was ordered by the Prussian Government to be substituted for arsenical compounds in 1843, and it is probable that to some degree the alteration has been successful, though in France it was found that phosphorus in this form became a popular agent for suicide and criminal poisoning. SAL PRUNELLA was at one time in high esteem, as it was believed that by the process adopted for making it the nitre was specially purified. Purified nitre was melted in an iron pot and a little flowers of sulphur (1 oz. to 2 lb.) was sprinkled on it, a little at a time. The sulphur deflagrating was supposed to exercise the purifying influence on the nitre. The actual effect was to convert a small part of the nitrate of potash into sulphate. It was first called Sal Prunella in Germany from the belief that it was a specific against a certain plum-coloured quinsy of an epidemic character. Boerhaave advised the omission of the sulphur, but believed that melting the pure nitre and moulding it was of medicinal value by evaporating aqueous moisture. Nitre and flowers of sulphur were deflagrated together before the Sal Prunella theory was invented, equal quantities being employed. The resulting combination, which was of course sulphate of potash, was known as Sal Polychrestum, the Salt of Many Virtues. SAL GEMMÆ. Sal Gemmæ or Sal Fossile was the name given to rock salt, particularly to the transparent and the tinted varieties. It was believed to be more penetrating than the salt derived from sea water, and this property Lemery ascribed to the circumstance that it had never been dissolved in water, and therefore retained all its native keenness. SPIRIT OF SALT.