necessary reductions, we have '' 12.777; 

 but ^| - ? = -0661 and 12.777 .0661 = 

 12.7109, which is the actual volume of air at the 

 end of the experiment when reduced to the same 

 pressure and temperature as it possessed at the be- 

 ginning. To find, farther, the proportion which 

 this loss of bulk bears to that of the whole air em- 

 ployed, we have 16.5 12.71O9 = 3.7891 and 

 ^~zz 4 ~ 5 - But atmospheric air contains ~ zz --- 



of oxygen gas, so that the loss in the bulk of air by 

 this experiment is rather greater than the propor- 

 tional quantity of oxygen gas which the atmosphere 

 contains. In another trial made in the same jar, 

 and under similar circumstances, the loss of bulk 

 which the air was found to have suffered, after the 

 necessary reductions wer : made, was ^ l - of the 

 whole. Hence, therefore, if it be granted that the 

 loss of bulk which the air suffered arose from the 

 r.ttraction of the carbonic, acid by the water of pot- 

 assa ; and if it be also allowed, that all the oxygen 

 gas of the air employed had completely disappeared, 

 it must be concluded, that the bulk of carbonic acid ' 

 produced nearly corresponded to that of the oxy- 

 gen gas lost. This, too, will appear more directly, 

 by comparing the diminution which a given bulk of 

 air suffers in germination, with the proportion of 

 oxygen gas which the atmosphere contains : Thus, 

 10O : 22 :: 16.5 : 3.63, which comes near to 3.78, 

 the actual loss of bulk which the air in the foregoing 

 experiment underwent. 



