Mr. Haycraft on the Specific Heat of the Gases. 265 



That the gas procured from animal fat contains more em- 

 pyreumatic vapour, is evident from its sensible qualities, which 

 may account for its greater specific heat, compared with that 

 procured from sea-coal. The gases, at the end of the experi- 

 ment, were exactly of the same temperature as when entering 

 into the calorimeters. 



No. *. 



The last experiment was repeated, except that the ole- 

 fiant gas was procured from alcohol and sulphuric acid. After 

 25 minutes, the calorimeter A had assumed the temperature 

 of 74°/^, and calorimeter B that of 75°*10; the surrounding 

 medium being 54° ; indicating the capacity of olefiant gas to 

 be 10643. 



No. 5. 



The last experiment was repeated, and gave a result of 

 10674; the medium result of experiments Nos. 4 and 5, be- 

 ing 10658, indicating the capacity of olefiant gas procured 

 from alcohol and from sea- coal to be almost exactly the same. 



No. 6. 

 Wishing to ascertain if the ethereal or empyreumatic va- 

 pour in olefiant gas affected its specific heat, I poured a few 

 drops of sulphuric ether into the part of the apparatus con- 

 taining atmospheric air, that the latter, as well as the olefiant 

 gas, being equally saturated with the vapours of ether, it might 

 be ascertained what effect that condition might have on the 

 capacities of the gases. The part B contained the olefiant 

 gas as before. After 40 minutes, both the calorimeters had 

 acquired a temperature of 85°-^, the surrounding medium 

 being 61°2 4 n . The inference, then, may fairly be made, that 

 it is the combined vapour that increases the specific heat of 

 olefiant gas. 



Experiments on the Air of Respiration. 



Having last year made more than ten experiments which 

 prove that the mixtures of carbonic acid with atmospheric air 

 exposed freely to water, and at a temperature of about 100°, 

 had a much less capacity for heat than atmospheric air had, 

 under ordinary circumstances, and this curious fact seeming 

 to throw some light upon the physiology of animal respira- 

 tion, I filled the part B with air from the lungs, and the part 

 A with atmospherical air. 



The heating apparatus was kept, by means of a lamp, at the 

 temperature of between 97°Ag and 100° ; }i;. After the end of 

 35 minutes, die calorimeter through which the air of respiration 

 p tated attained the temperature of 59°^, and the other that 



Vol. 61. No. 318. Oct. 1824. L 1 of 



