Page:Collier's New Encyclopedia v. 09.djvu/189

SULPHUR 155 SULPHUBIC ACID bers of brickwork, in which the sulphur condenses in light flocks, known as flowers of sulphur. When melted and cast, these form the roll brimstone of commerce. Sulphur can also be easily ex- tracted from iron and copper pyrites. At ordinary temperatures, sulphur is a brit- tle, insoluble, inodorous solid, of a lemon- yellow color, a bad conductor of heat, and a non-conductor of electricity. By friction with silk or wool, it becomes negatively electrified. It is a highly in- flammable substance, burning readily in the air at about 450° or 500° F., and giving off suflfocating fumes of sulphur- ous acid gas. At 239° F. it melts, form- ing a yellow liquid, and slightly increas- ing in bulk. Provided the above temperature is not exceeded, it remains nearly transparent on cooling, but be- comes gradually opaque from interior molecular changes. In close vessels, it may be distilled by raising the heat to about 834° F. Sulphur is very remark- able as affording a striking instance of the occurrence of the allotropic condition of matter. Hydrogen and sulphur vapor, when burnt, form sulphuretted hydrogen. Burnt in oxygen, heated with chlorine, bromine, and iodine, it unites with them, forming well-known compounds. The vapor of sulphur passed over red-hot charcoal forms bisulphide of carbon. Nearly all the metals combine with it at ordinary or increased temperatures. Sulphur combines to form the following acids: Sulphurous acid HjSOs Sulphuric acid H2SO4 Dithionous acid H2S20a Dithionic acid H2S20e Trithionic acid H2S30«  Tetrathionic acid H2S40«  Pentathionic acid HsSsO* Sulphur unites with chlorine in two proportions, forming a dichloride and a chloride. The dichloride, SCU, is pre- pared by transmitting a current of chlorine over melted sulphur, the result- ing dichloride being collected in a per- fectly dry receiver. It is a dark yellow liquid, very volatile, and possesses a peculiar penetrating disagreeable odor. It emits fumes when exposed to moist air, and when dropped into water grad- ually decomposes into hydrochloric and sulphurous acids and free sulphur. It has a sp. gr. of 1.658, and boils at 280° F. It is used for vulcanizing india-rub- ber goods. By saturating dichloride of sulphur with chlorine, a dark red liquid chloride is formed. There is reason to suppose that a bichloride exists but it has not yet been isolated. The corre- sponding bromides are liquids analogous to the chlorides. The iodide is a crys- talline brittle gray solid. With nitrogen, sulphur forms a bisulphide which crys- tallizes in beautiful golden-yellow rhombic crystals. It detonates power- fully by percussion, or when heated to 314° F. Bisulphide of carbon dissolves it readily, alcohol, ether, and oil of tur- pentine sparingly, and water not at all. Symbol S ; at. wt. 32. Prior to 1902 the chief source of sulphur was Sicily. In that year, however, by a remarkable series of inventions, following years of research, Herman Frasch, a chemist, suc- ceeded in extracting sulphur from vast deposits in Louisiana and Texas. The process, in brief, consists in melting the sulphur, which lies underground, by superheated water. It is then driven to the surface by compressed air. The pro- duction in the United States, almost en- tirely from Louisiana, was in 1919, 1,210,000 long tons, valued at $16,750,- 000. There were exported 224,712 long tons, valued at $6,325,552. SULPHURETTED WATERS, hot or cold mineral waters holding in solution sulphides or free sulphuretted hydrogen. They are stimulant, diaphoretic, and al- terative. The sulphuretted hydrogen im- parts to them a nauseous odor like that of rotten eggs. The chief thermal sul- phuretted waters are those of Aix-la- Chapelle, Baden, near Vienna, Aix-les- bains, etc. ; the chief cold ones are Harro- gate and Bocklet. Such baths are recom- mended in cutaneous, hepatic, uterine, rheumatic, gouty, neuralgic, and other diseases. SULPHURIC ACID, a very important acid which occurs in nature in large quantities, both in the vegetable and mineral kingdoms, in combination v/ith the various bases, more particularly the alkalies, alkaline earths, and the oxides of iron, copper, lead, zinc, alumina, etc. Its mineral combinations are generally known as vitriols, a name which, in the case of the sulphates of iron, copper, and zinc, has been transferred to the manu- factured products. Sulphuric acid is formed by the oxidation of sulphurous acid, or some other oxide of sulphur. In its perfectly anhydrous condition, it oc- curs as a white crystalline fibrous mass, somewhat resembling asbestos in appear- ance. It can be molded in the fingers like wax without charring the skin; it fumes in the air, and is very delique- scent, hissing violently when thrown into water; thereby becoming sulphuric acid. It chars wood, paper, sugar, and other similar substances, by abstracting water from them. It melts at 65° F., and boils at 110° F., forming a colorless vapor. It