MOTIVE POWEH OF HEAT. 



1 metre of mercury (see Memoire already cited), 

 taking for the unit the specific heat of the same 

 weight of air under the pressure of O m .7GO. 



According to the law that specific heats follow 

 with relation to pressures, it is only necessary to 

 have observed them in two particular cases to 

 deduce them in all possible cases : it is thus that, 

 making use of the experimental result of MM. 

 Delaroche and Berard which has just been given, 

 we have prepared the following table of the specific 

 heat of air under different pressures: 



SPECIFIC HEAT OF Am. 



The first column is, as we see, a geometrical 

 progression, and the second an arithmetical pro- 

 gression. 



