Sullage-head
See HEAD.
Sulphates are definite compounds of sulphuric acid with the salifiable bases. Sulphites are definite compounds of sulphurous acid with the bases. Sulphur, usually called brimstone, is sold in powder and in solid pieces. This substance exists abundantly in nature, both free and in combination. It is found in the neighborhood of volcanoes, especially in the island of Sicily. It exists in combination with various metals, forming sulphides, and as a constituent of sulphuric acid it is met with in gypsum and other minerals. It is volatile, and sublimes by heat. Advantage is taken of its volatility to separate it from the mineral impurities with which it is found associated. Iron pyrites contain 50 per cent of sulphur, which is separated by roasting or heating the pyrites in tubes and running off the sulphur into vessels of water. Sulphur melts at 239 deg. F. At this temperature it is thin and fluid as water; when further heated it thickens, with a darker color; and at 480 deg. F. it is so tenacious as to almost refuse to run. Poured into water in this condition it will retain for a long time a very tenacious and soft condition, followed by a state of brittleness again. In its soft condition it is sometimes called putty sulphur. In this state it may be used to take impressions of medals, coins, etc. See SULPHUR IMPRESSIONS. Sulphurets are sulphides or combinations of alkalies or metals with sulphur. Sulphuric Acid (the oil of vitriol, or vitriol of commerce) is a powerful acid of great interest to chemists and manufacturers. It is found in the craters of volcanoes and in mineral springs; but it is generally procured by burning nitre and sulphur in large furnaces, the fumes from which are delivered into large lead chambers, where, by the action of steam and air introduced, it is deprived of an atom of oxygen and becomes sulphuric acid. See NITRE.