= ae oe ee re eee 
Mechanical’ Theory of Heat to the Steam Engine. 185 
verted, then uncompensated transformations have come into 
play, and the magnitude N has an assignable value, which how- 
streams from one vessel, in which it was under a greater pres- 
; this 
__ Many cases of interest to know how much each single one of 
_ the last has contributed to the production of the whole sum of 
uncompensated transformations. For this purpose imagine that 
the mass, after the change in condition ahich we wish in this 
way to investigate, is brought back by any invertable process to 
its original condition. In this way we obtain a small circular 
up during the same, and the temperatures belonging to it, the 
negative integral — -[' sa gives the uncompensated change which 
has occurred in it. Now as the restoration which has taken 
place in an invertable manner can have contributed nothing to 
egat ecause it is lost for urce of heat, here on th r hs is consid- 
ered as positive. All the elements of heat contained in the integral ot ee 
their sign, and with them at the same time the whole integral, consequently in order 
that the equation should remain correct notwithstanding the change, it was neces- 
sary he sign on the other side also. 
SECOND SERIES, VOL. XXIJ, NO. 65.—SEPT., 1956, 
24 
* 
