142 Dr Bischof's Examination of Three Inflammable Gases 



the carbon, which had been deposited in the first experiment, 

 not having been removed. 



In a mean of three experiments nearly corresponding with 

 one another, 1 vol. of decomposed pit-gas of the first experi- 

 ment had afforded, by detonation with 3 vol. of oxygen, an 

 absorption of 1.367 vol., and potash had absorbed 0.528 vol. 

 of carbonic acid gas. Assuming that the carbonic acid gas 

 was produced from carburetted hydrogen gas alone, the gas ex- 

 perimented on consisted of 



Carburetted hydrogen gas, . . . 0.528 vol. 



Hydrogen gas, .... 0.207 • • • 



Foreign gas, .... 0.265 ... 



1.000 

 The pit-gas of the second experiment, when 1 vol. was de- 

 tonated with 3 vol. oxygen, afforded an absorption of 1.289 vol., 

 and the carbonic acid gas amounted to 0.5 vol. Making the 

 same assumption as before, the gas consisted of 



Carburetted hydrogen gas, . . . 0.500 



Hydrogen gas, . . . . 0.172 



Foreign gas, ..... 0.328 



1.000 

 In the first experiment, therefore, there was decomposed 

 only 0.10, and in the second only 0.086 vol. of the pit-gas in 

 the red-hot porcelain tube. This difference agrees also with 

 the smaller increase of volume in the second experiment. As, 

 however, the atmospheric air could not be entirely removed ; 

 and as, likewise, during the long continuance of the experi- 

 ment, the gas would be rendered impure by this air from the 

 confining water, there can be no doubt that a portion of the 

 hydrogen is burned in the red-hot tube at the expense of the 

 oxygen of the atmospheric air. The true amount of gas 

 decomposed must +herefore have been somewhat greater. 

 This also agrees with the fact, that in the decomposed gas 

 about twice as much foreign gas was found as in the undecom- 

 posed gas, according to the analysis which follows below. I 

 omitted examining more closely the foreign gas ; but doubt- 

 less it consisted, at least chiefly, of nitrogen. After subtract- 

 ing the foreign gas, the increase of volume amounted, accord- 



