THE MECHANICAL EQUIVALENT OF HEAT. 
405 
bridge were so nearly equal, and were so arranged, that they would be affected to 
the same degree by any temperature changes. 
The figure shows the comiections—■ 
BC the arm containing the coil. 
BD contains the two large German silver coils. 
AC, AD the two German silver wires forming the remaining arms of the 
bridge. 
Gi, G 3 the high and low resistance galvanometers. 
L, S the Clark cells and storages. 
K the mercury rheostat. 
Table VIII.—The following Table gives the observations taken September 20 , 1892. 
Time. 
3.40 
3.46 
3.. 54 
3.56 
4. 3 
4.17 
4.21 
4.25 
4.33 
4.. 36 
4.38 
4.50 
4.59 
5.50 
6 . 0 
7.12 
7.18 
7.26 
7.30 
7.45 
8 . 0 
No. of 
Clark cells. 
1 
2 
3 
4 
5 
6 
1 
2 
3 
4 
5 
Temperature at which bridge is 
balanced. 
E„,. 
379-4 
363-4 
.333-4 
333-6 
292 
240-4 
} 
C°. 
Rat C° 
(in Legal ohms). 
cR. 
21-226 
8-7790 
X 
20-818 
8-7671 
a; + -0119 
20-100 
8-7458 
a; +-0332 
19-080 
8-7157 
33+-0633 1 
1 
17-760 
8-6771 
a; + -1019 
16-202 
8-6316 
a; + -1474 
21-306 
8-7814 
X 
20-895 
8-7692 
a: + -0122 
20-130 
8-7468 
iti -|- *0346 
19-067 
8-7156 
a; +-0658 
17-765 
8-6772 
a: +-1042 
Of the second series of experiments, the first was taken immediately after entering 
the laboratory, when the arms AC, AD (being very near one observer, and the gas 
having been lighted) had not probably reached a state of thermal equilibrium, but 
they evidently did so during the series. 
