208 MR HAYCRAFT on the Specific Heat of the Gases. 



Azote. 



Of Azote I shall merely state, that, last year, I performed si- 

 milar experiments upon this Gas, the results of which were per- 

 fectly analogous with those now detailed ; and as aU the experi- 

 ments agree that it has by volume the same specific heat as at- 

 mospheric air, namely 1000, I thought it needless to repeat 

 them. 



Carburetted Hydrogen. 



In my former experiments on Carburetted Hydrogen, pro- 

 cured from the decomposition of sea-coal, I concluded that it also 

 had the same capacity as atmospheric air ; but I have since found 

 that the capacity of this Gas varies extremely, according to the 

 modes in which it is procured. That produced from sea-coal seems 

 to have a capacity nearly equal to the standard ; that from the 

 decomposition by heat of animal fat, has a much greater capacity. 

 From the following experiments, however, it will appear that 

 olefiant Gas owes its increased capacity to the empyreumatic or 

 ethereal vapour with which it is usually combined. 



No. 1. 



This experiment I conducted in the same way as No. 1 . on 

 Hydrogen Gas. The part B was filled with olefiant Gas, obtained 

 from the gas-pipes of a public company. The calorimeters at 

 the beginning of the experiment contained water of the tem- 

 perature of 50. At the end of 50 minutes the calorimeter A 

 had acquired its utmost temperature of 92 / , and of B that 

 of 93 io 5 the surrounding medium being 66 -fc. 



