Ee = ee 
Mechanical Theory of Heat to the Steam Engine. 41 
by the expansion of the steam, was considered as known, while 
here, the expansion is determined according to the volume, and 
the change of temperature must first be calculated from this. 
(3.) The case of a machine with injurious space and imperfect 
expansion, in which, of the former advantageous conditions 
only this one remains, that the steam in the cylinder during the 
influx exerts the same pressure as in the boiler, so that thus the 
volume has the least possible value. With this case, finally, are 
connected those already mentioned, in which also the lost advan- 
tageous condition is absent, inasmuch as the volume instead of 
the smallest possible value has other given values. 
All these cases are also calculated according to Pambour’s 
theory for the sake of comparison, with the exception of the 
first, for which equations (29a) and (290) do not suffice, inasmuch 
as even that one of them which is determined for a less pres- 
Sure can still only be applied up to 4, or at the utmost down- 
‘ards to $d of an atmosphere, while here the pressure is to 
diminish to 1th of an atmosphere. : 
The numbers resulting from our equations for this first case, 
are as follows: 
Vol. before expansion. | Vol. after expansion: | w Brie, 
37 | 
6345 ee 50460 
0°38 
For all other cases, the results are embraced in the accompany- 
Ing table, in which again the numbers which refer to the machine 
Without injurious space, are separated from the others by a line. 
Only the numbers which hold good for the volume after the ex- 
Pansion are cited, because the values before the expansion are 
given, inasmuch as they in all cases are smaller in the ratio of ¢:1. 
RA ites epee 
bia. ts 
0992 | 159%99 
/ 1010 |” _150°-99 
aie 145 “6 
1% 137: 
1 181 -02 
cnt Pua | 190 49 
the of s 
how , according to this, 
of heat delivered by the souree 
¢ gram of steam, as muc 
necessary to heat the mass, W 
one kj 
the boil 
SECOND 
