216 MR HAYCRAFT on the Specific Heat of the Gases. 



inversely as their specific gravities; and, 2dly, That different 

 states of combinations of the Gases with aqueous and other va- 

 pours, affect the capacities of the Gases, and that probably, in 

 some instances, in a regular arithmetical progression, correspond- 

 ing with the arithmetical rate of expansive force of the Gases in 

 different states of combination with vapour. The most interest- 

 ing result to the physiologist is, that the air of respiration, at a 

 temperature of between 100^ and 95, has a less specific heat 

 than atmospherical air. Many experiments were made which are 

 not here detailed, which shewed that the air of respiration, at the 

 temperature of 102 and upwards, and of 91 and downwards, had 

 a capacity the same as that of atmospherical air. I should feel 

 a hesitation in stating these results, had not experiments, very 

 often repeated, during a course of several months, warranted me 

 in my conclusions. 



