132 
PROFESSOR R. THRELFALL AND MR. J. H. D. BREARLEY 
Table XII.— Showing Resistance of a Film containing 7 per cent. (?) of Insoluble 
Sulphur. 
Dare. 
Tempera¬ 
ture of 
sulphur. 
Tempera¬ 
ture of 
air. 
Voltage 
iu volts. 
Specific 
resistance. 
Remarks. 
1892. 
Nov. 18 
°c. 
22-8 
°C. 
22-8 
258 
1-905 x 10 M 
Taken immediately film was sup- 
25 
n 
22-7 
23-8 
312 
1-47 x 10 23 
posed to be dry 
First application of voltage. Bat- 
„ 25 
5? 
11 
11 
1-85 x 10 23 
tery not reversed 
After about 3 minutes. Battery 
„ 25 
11 
91 
2-18 x 10 23 
not reversed 
After 25 minutes. Battery not 
„ 25 
1 J 
il 
11 
2-05 x 10 23 
reversed 
Mean resistance battery both wavs 
„ 25 
1 1 
11 
155 
3-4 x 10 33 
—after 3 minutes 
Battery both ways—after say 10 
., 29 
23-5 
24-5 
311-7 
2-61 x 10 23 
minutes 
Mean after 4 minutes. Batterv 
„ 29 
11 
il 
11 
7-7 x 10 23 
both ways 
After charging one way for 1 hour 
„ 29 
11 
11 
154 
1-068 x 10 26 
20 minutes 
Affer charging one way to test for 
Dee. 1 
23-6 
22 
28S-6 
2-1 x 10 23 
Ohm’s law in steady state 
Least resistance obtainable on re- 
1 
11 
11 
11 
6-079 x 10 25 
versal after 30 minutes charge 
Greatest resistance obtainable, bat- 
„ 2 
21T 
20-6 
304-9 
3-5 78 x 10 23 
tery one way for 30 minute 
charge 
Mean resistance both ways after 
„ 2 
97 
91 
2-3 x 10 23 
3 minutes 
After very slow heating—battery 
„ 2 
100 
11 
only applied at this temperature 
Resistance decreasing so fast as to 
be immeasurable, at most specific 
resistance about 2 x 10 21 
Film of April 1 7th, 1893. 
It has been already stated that some uncertainty attached to the constitution of the 
film just considered, and tins was increased when, on examining the electrodes by the 
true plane, it was found that one of them had not preserved its perfect flatness. 
Another circumstance conspired to induce us to re-examine mixed films. For this 
purpose the plates were again adjusted for flatness, and a proper zinc dish constructed 
to carry ice on the upper plate. In order to obtain further security against surface 
action we reverted to our old plan of erecting a quartz rod fence along the sulphur 
surface between the dish and the upper plate. The sulphur employed was some of 
