Page:Reflections on the Motive Power of Heat.djvu/111

Rh 1 metre of mercury (see Mémoire already cited), taking for the unit the specific heat of the same weight of air under the pressure of 0m.760.

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 Bérard which has just been given, we have prepared the following table of the specific heat of air under different pressures:

The first column is, as we see, a geometrical progression, and the second an arithmetical progression.