CLARK CELL AS A STANDARD OF ELECTROMOTIVE FORCE. 
615 
Table XIV. 
Date. 
Temperature 
Difference 
Temperature 
Notes. 
of cell. 
from JNo. 1. 
of No. 1. 
August 10 .... 
O 
16-4 
0 
16-4 
2.30 . . 
167 
0 
167 
Packed in ice. 
„ 3.50 . . 
51 
„ 4.30 . . 
63 
„ 5.30 . . 
71 
167 
Readings still changing. 
August 12, 10.30 
0 
74 
16-9 
Repacked in ice at 10.32. 
„ 10.55 . . 
0 
74 
16-9 
„ 1.15 . . 
0 
74 
17 
„ 4.30 . . 
0 
75 
17 
Repacked at 5.10. 
» 5.15 . . 
0 
75 + 
171 
„ 7. 0 . . 
0 
76 
17-4 
August 13, 10. 0 a.m. . 
0 
74 
167 
Placed in water of temperature 
16°7 at 10.5. 
„ 10.30 . . 
13 
30 
„ 11. 5 . . 
16-6 
11 
„ 6.10 . . 
17-5 
6 
167 
August 14, 9.40 . . 
17-8 
7 
177 
„ 4.50 . . 
18-8 
7 
18-5 
August 15, 10. 0 . 
18-4 
6 
18-4 
Placed in water at 32° at 12.30 
on August 17, and allowed to 
cool. 
August 18 .... 
18-3 
2 
18-3 
„ 19 .... 
17-2 
2 
17-2 
November 2 ... 
14-4 
1 + 
14-4 
) 
„ 14 ... 
9-2 
1 + 
9-2 
> Cells all at one temperature. 
December 22 ... 
0 
2- 
0 
When the cell was left on August 10 the readings were still changing though it 
had been in ice for three hours. 
On August 11 it appeared that some moisture had got among the glass-wool, the 
cell was taken out and repacked, taking care to insulate the leads thoroughly with 
gutta percha. After this the difference rose to 66, but was still increasing at 5.40. 
Throughout the next day and up to 10 a.m. on August 13 it was steady, the mean 
reading being 74'6, and the average temperature of the standard 17°. After the last 
observation the cell was placed in water at 16°*7. At first there was a rapid fall, but 
after a time the fall ceased and a steady difference of some 6 or 7 of our units 
persisted all through the next day. 
On August 17 the cell was placed in warm water at 32° and allowed to cool. On 
August 18 the difference at about 18° was 2, and this continued through the next 
day. Before the cell was placed in ice the difference between it and the standard 
