126 
PROFESSOR R, THRELFALL AND MR. J. H. D. BREARLEY 
then heated and observations made at from 60° to 64° C. The resistance was found 
to have diminished, the conduction was unsteady and the usual effects were observed. 
With battery both ways after the steady state was reached the conduction was found 
to have increased between 60° and 64 0, 8 in the ratio of 44'2 to 31'2 (the respective 
elongations deduced from 24 observations). The value of the resistance at 64 0- 8 C. 
is 6‘9 X 10 2 * C.G.S. The value of the specific inductive capacity at 67° C. was 
apparently 4‘25, and at 98’5 could not be distinguished from this ; the temperature of 
the standard did not change meanwhile. At 100° C. the resistance was much 
decreased and the conduction unsteady, the effect on reversal was not so strongly 
marked. Thus : 
Temperature, 100°'5 C. 
Battery A. 
Double elongation.472 
Ditto, reversed.465 
Battery B. 
Double elongation (at once).444 
Ditto, reversed.465 
The results of these experiments are collected in the following tables :— 
Table X.—Showing Variation of Specific Inductive Capacity of Film of 
November 9, 1892. 
Date. 
K. 
Temperature of 
sulphur. 
Temperature of 
standard and 
resistances. 
Voltage. 
1892. 
° C. 
° C. 
Nov. 9 . . . 
4-18 
22-8 
22-8 
40 Clark's 
„ 11 . . . 
4-18 
19-9 
20-3 
3 3 
„ 16 . . . 
4-247 
21-5 
21-5 
3? 
„ 17 . . . 
4-247 
67'5 
21-4 
40 Clark’s and 262 volts. 
„ 17 . . . 
4-247 
98-5 
21-15 
S3 33 3 3 
In the above table no corrections are applied for increase in the linear dimensions 
of the electrodes. If this be done it will be found that the constancy of the capacity 
as the temperature rises indicates a small positive temperature coefficient in the 
specific inductive capacity which may, however, be due to a partial annealing. This 
is dealt with later when we had command of a better standard. 
