MR HAYCRAFT on the Specific Heat of the Gases. 205 



Experiments on Hydrogen. 



Hydrogen Gas was procured from the decomposition of wa- 

 ter by means of sulphuric acid and zinc. The part B was filled 

 with the same, and the following experiments were made. 



No. 1. 



In this experiment the calorimeters were filled with water of 

 the same temperature, and the process was conducted on rather 

 a different principle than the former, namely, it was continued 

 until the calorimeters ceased to rise in temperature, or rather, 

 till the temperature began to fall. This latter circumstance 

 would take place when the heat communicated by the Gas was 

 exactly equal to that abstracted by the colder surrounding me- 

 dium. The number of degrees of temperature, then, which 

 each Gas would sustain in its calorimeter, will be the ratio of its 

 power for giving out heat, and consequently of its capacity for 

 caloric. 



The temperature of calorimeter A, at the beginning of the 

 experiment, was about 50, and after 105 minutes, the tempera- 

 ture of calorimeter A was 82 |-f, and that of B, containing Hy- 

 drogen Gas, was 82 |, and the surrounding medium 60%^, in- 

 dicating the comparative capacity of Hydrogen to be 98.64, be- 

 ing a difference so trifling, that it may be regarded as the same 

 as that of atmospheric air ; if we make allowance for the evident 

 greater ratio in its heating, and the smaller ratio of its rate of 

 cooling at the end of the experiment. This will be seen by the 

 following Table. 



