354 . Analysis of Scientific Books* 



equal volumes of the vapour and chlorine: it could not, there- 

 fore, be the same as the hydro-chloride of carbon from olefiant 

 gas, since it contained twice as much carbon and hydrogen. It 

 was, therefore, treated with excess of chlorine in sun-light : 

 action slowly took place, more chlorine combined with the sub- 

 stance, muriatic acid was formed, and, ultimately, a fluid tena- 

 cious triple compound of chlorine, carbon, and hydrogen was 

 obtained; but no chloride of carbon. This is a remarkable cir- 

 cumstance, and assists in shewing, that though the elements are 

 the same, and in the same proportions as in olefiant gas, they are 

 in a very different state of combination. 



Mr. Faraday next proceeds to detail the experiments by which 

 he ascertained the tension of the most volatile part of the condensed 

 oil gas liquid ; it appears to be equal to about 4 atmospheres at the 

 temperature of 60°. He also adverts briefly to the properties of 

 the other portions of the liquor, and gives an outline of such facts 

 as others have determined respecting them. In conclusion, he 

 observes, that the importance of these vapours in oil gas, as con- 

 tributing to its very high illuminating powers, will be appreciated, 

 when it is considered that with many of them, and those of the 

 denser kind, it is quite saturated. On distilling a portion of 

 liquid, which had condensed in the pipes leading to an oil gas 

 gasometer, at Apothecaries' Hall, he found it to contain portions 

 of the bi-carburet of hydrogen. It was detected by submitting 

 the small quantity of liquid which distilled over before 190° to a 

 cold of 0°, when the substance crystallized from the solution. It 

 is evident, therefore, that the gas from which it was deposited 

 must have been saturated with it. On distilling a portion of 

 recent coal gas tar, as was expected, none could be detected in it, 

 but the action of sulphuric acid is sufficient to shew the existence 

 of some of these bodies in the coal gas itself. 



With respect to the probable uses of the fluid from com- 

 pressed oil gas, it is evident, in the first place, that being thus 

 Volatile, it will, if introduced into gas which burns with a pale 

 flame, give such quantity of vapour as to make it brightly illu- 

 minating ; and even the vapour of those portions which require 

 temperatures of 170°, 180°, or higher, for their ebullition, is so 

 dense as to be fully sufficient for this purpose in small quantities. 

 A taper was burnt out in a jar of common air over water ; a portion 

 of fluid boiling at 190° was thrown up into it, and agitated ; the 

 mixture then burnt from a large aperture with the bright flame 

 and appearance of oil gas, though of course many times the quan- 

 tity that would have been required of oil gas for the same light 

 was consumed : at the same time there was no mixture of blue- 

 ness with the flame, whether it were large or small. 



The fluid is also an excellent solvent of caoutchouc, surpassing 



