144 Dr Bischof's Examination of Three Inflammable Gases 



Thence is to be subtracted the quantity of nitrogen contained 



in the three volumes of oxygen, . . . 0.1158 vol. 



Consequently foreign n on-inflammable gas in the pit-gas, 0.1672 

 Experiment I. gave, ..... 0.1G92 



Mean, ...... 0.1682 



The quantity of inflammable gas in the gaseous mixture 



amounted therefore to. .... 0.8318 



If, however, we assume that the inflammable gas is equal to 



the half of the absorption by detonation, we have, 0.8506 



which harmonizes pretty nearly with the direct determination 

 of the foreign gas. The difference cannot surprise us when 

 we consider, that in agitating a gaseous mixture with a solu- 

 tion of sulphuret of potassium, some nitrogen is always absorbed 

 along with the oxygen, and so much the more the less there is 

 of it in proportion to the latter. Doubtless, therefore, the 

 nitrogen is somewhat underrated in the oxygen employed for 

 detonation. We ought, therefore, to place more confidence in 

 the indirect determination of the foreign gas, according to 

 which it amounts to 0.1494 vol., than in the direct mode. 



According to the assumption formerly made, that the in- 

 flammable gases are equal to half the absorption by detona- 

 tion, only the binary combination of carburetted hydrogen and 

 olefiant gas can occur, and it results that the composition is 

 the following : 



Carburetted hydrogen, . . . 0.8308 



Olefiant gas, ..... 0.0198 



Foreign gas, .... 0.1494 



1.0000 

 There is requisite for the perfect ignition of 



0.8308 v. carburetted hydrogen gas, 1.6616 v. oxygen. 

 0.0198 v. olefiant gas, . . 0.0594 v. 



Absorbed by sulphuret of potassium, 1.1404 v. 



2.8614 

 There was used for detonation, . 3 v. oxygen. 



The nitrogen contained in it amounted to, 0.1158 



Pure oxygen, . . • 2.8842 



The difference between this and the previous number is 



