The great diversity of opinions entertained by several of the most celebrated of the French chemists regarding the nature of this com- pound, which was originally noticed by Lampadius in the distillation of a mixture of pyrites and charcoal, induced the authors to under- take the present analysis, without any knowledge that it was again nearly at the same period under examination in France. The original opinion of Lampadius was, that it consisted of sulphur and hydrogen, and his opinion was also supported by Vauquelin, Robiquet. and the younger Berthollet. The elder Berthollet had supposed it to be a compormd of sulphur, hydrogen, and carbon; but, according to lVIessrs. Clement and Desormes, hydrogen had appeared not to be one of its constituents, a result which is now adopted in a late re- port of Messrs. Berthollet, Thenard, and Vauquelin, and is here further confirmed by the inquiries of Professor Berzelius and Dr. Marcet.
Their joint paper is divided into four parts,. the first of which de- scribes the preparation and general properties of the compound; in the second. the authors examine whether hydrogen be present in it; in the third, the presence of carbon is ascertained; and the fourth, the proportion of its constituents is determined.
The preparation consists in distilling sulphur through a red-hot tube of porcelain containing well burned charcoal, condensing the oily product in water, and subsequently rectifying it by very slow distillation at a heat between 100° and 110°, by which it is freed from a redundant quantity of sulphur which it always contains when first procured. The fluid is then perfectly transparent and colour. less. It has an acrid, pungent, somewhat aromatic taste, with a smell that is nauseous and fetid. Its specific gravity is 1272. It boils between 105° and 110°, and does not congeal at 50" below zero. It is soluble in alcohol, in ether, and in all oils whether fixed or volatile, and in alkalies; but it does not unite with water. with acids, or with any metallic substances, and even suffers no change when heated in contact with potassium.
For the purpose of determining whether hydrogen was present, the vapour of it was exploded with oxygen in the first instance. In the next, a current of oxymuriatic gas was passed through the oily liquid. Thirdly, attempts were made to burn it in oxymuriatic gas. Fourthly, the vapour of it was passed through liquefied muriate of silver; and Lastly, through various metallic oxides; but in no instance was there any appearance of water being produced, or any other evidence of the presence of hydrogen in the compound.
The presence of carbon was ascertained by the formation of carbonic acid in the combustion of the vapour with oxygen. When the oil itself was set on fire in oxygen gas, the heat was sufficiently
