which are evolved in Coal-Mines. 131 



of a comparison of the volume of the gaseous mixture employed 

 for analysis, with the volumes which disappear by detonation, 

 and by the use of potash, I have deduced equations for the 

 six possible binary combinations of hydrogen, carbonic oxide, 

 carburetted hydrogen, and defiant gases, in order, with their 

 assistance, to determine what combinations can occur in a 

 given case. In like manner, equations were deduced for 

 the four possible ternary combinations of these inflammable 

 gases, and for this purpose three were deduced for each single 

 combination, by which means it can likewise be determined 

 what combinations can occur in a given case. 



The experiments in § 3 have proved that in pit-gas olefiant 

 gas is present. According to the equations of the binary 

 combinations which contain olefiant gas, only that one consist- 

 ing of carburetted hydrogen and olefiant gas can occur. As 

 in this combination the volume of the gas which has dis- 

 appeared by detonation amounts to double the volume of 

 the gaseous mixture employed, the latter must amount to 

 L9685 _ 0.97675. Hence, the residue of 0.02325 vol. must have 

 been a foreign non-inflammable gas. According to § 1 no 

 oxygen can be contained in this residue. If we consider, 

 however, that the pit-gas employed in the analysis came 

 in contact with water in various ways during the washing 

 with potash and the filling of the bottle, it may well be as- 

 sumed that the pit-gas has acquired some atmospheric air by 

 exchange. As, however, the pit-gas from Gerhard's Stollen, 

 as we shall soon see, contains a large quantity of nitrogen, it 

 is probable that the residue consisted chiefly of that gas. 

 This nitrogen was thus, therefore, an essential component 

 part of the pit-gas. The small quantity of the residue did 

 not, however, admit of farther analytical investigations. If 

 now, we take 0.97675 vol. as the quantity of the inflammable 

 gas in the analyzed pit gas, we find that it consists of 



Carburetted Hydrogen Gas, . . . . 0.9136 vol. 



Olefiant Ga>, 0.0632 ... 



Foreign Gas, 0.0232 .. 



1.0000 



Upon the supposition that the pit-gas is a ternary combi- 

 n.ition, the equations coincide only with the combination of 



