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On new Compounds of Carbon and Hydrogen, and on certain other 

 Products obtained during the Decomposition of Oil by Heat. By 

 M. Faraday, F.R.S. Cor. Mem. Royal Academy of Sciences of 

 Paris, SfC. Read June 16, 1825. [Phil. Trans. 1825, p. 440.] 



The experiments of which the results are detailed in this paper, 

 were made principally on the fluid which is found to be deposited in 

 considerable quantity when oil-gas is compressed. This fluid, as ob- 

 tained at the works of the Portable Oil-gas Company, is colourless, 

 of a specific gravity less than that of water ; insoluble in water ex- 

 cept in very minute quantities ; soluble in alcohol, ether, oils, &c. ; 

 and combustible, burning with a dense flame. It is strikingly distin- 

 guished from the oil from which it originated, by not being acted 

 upon to any extent by solutions of the alkalies. 



Part of this fluid is very volatile, causing the appearance of ebul- 

 lition at temperatures of 50 or 60 ; other parts are more fixed, re- 

 quiring even 250, or above, for ebullition. By repeated distillations 

 a series of products were obtained from the most to the least vola- 

 tile, the most abundant being such as occurred from 1 70 to 200. 

 On subjecting these, after numerous rectifications, to a low tempe- 

 rature, it was found that some of them concreted into a crystalline 

 mass, and ultimately a substance was obtained from them, princi- 

 pally by pressure at low temperatures, 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 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, 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. Potassium 

 exerts no action upon it below 186. 



This substance was analysed by being passed over red-hot oxide 

 of copper, and by detonation of its vapour with oxygen. The re- 

 sults obtained were, that it consists of 2 proportionals of carbon, and 

 1 of hydrogen = 13; and that in the state of vapour 6 propor- 

 tionals of carbon and 3 of hydrogen are present to form 1 volume, 

 which is consequently of the specific gravity of 39, hydrogen being 

 1. It is named in the paper bicarburet of hydrogen. 



Experimenting with the most volatile portions of the liquid, a por- 

 tion was obtained, which, though gaseous at common temperatures, 

 condensed into a liquid at 0. This was found to be very constant 

 in composition and properties : it was very combustible : it had a 

 specific gravity of 27 or 28 as a gas, as a liquid that of 0'627, being 

 the lightest substance, not a gas or vapour, known. When analysed, 

 it was found to consist of one proportional of carbon 6, and one of 



