274 Proceedings of the Royal Society, 



to the least volatile, the most ahundant being such as occurred 

 from 170° to 200*^. On subjecting these, after numerous rectifi- 

 cations, to a low temperature, it was found that some of them 

 concreted into a crystalline mass, and, ultimately, a substance 

 was obtained from them, principally by pressure at low tempera- 

 tures, which upon examination, proved to be a new compound of 

 carbon and hydrogen. At common temperatures it appears as a 

 colourless transparent liquid, of specific gravity 0.85 at 60*^., 

 having the general odour of oil gas. Below 42® it is a solid 

 body, forming dendritical transparent crystals, and contracting 

 much during its congelation. At 0° it appears as a white or 

 transparent substance, brittle, pulverulent, and of the hardness 

 nearly of loaf sugar. It evaporates entirely in the air : when 

 raised to 186<=* it boils, furnishing a vapour, which has a specific 

 gravity of 40 nearly, compared to hydrogen as 1 . At a higher 

 temperature the vapour is decomposed, depositing carbon. The 

 substance is combustible, liberating charcoal, if oxygen be not 

 abundantly present. Potasium exerts no action upon it below ISS'^*. 



This substance was analyzed by being passed over red hot 

 oxide of copper, and by detonation of its vapour with oxygen. 

 The results obtained were, that it consists of 



2 proportionals of Carbon - - - 12 



\ ^— ^— .— Hydrogen - - 1 



18 



and, that in the state of vapour, six proportionals of carbon and 

 three of hydrogen are present to form 1 volume, which is conse- 

 quently of the specific gravity of 39, hydrogen being 1. It is 

 named in the paper Bi-car^buret of Hydrogen. 



Experimenting with the most volatile portions of the liquid, a 

 product was obtained, which, though gaseous at common tempe- 

 ratures, condensed into a liquid at 0°. This was found to be 

 very constant in composition and properties. It was very com- 

 bustible. It had a specific gravity of 27 or 28 as a gas ; as a 

 liquid that of O.C 27, being the lightest substance, not a gas or 

 vapour, known. When analyzed, it was found to consist of one 



