ELECTRO-CHEMICAL EQUIVALENT OF SILVER. 
Table IV. 
435 
Time. 
Difference 
of 
weight. 
Square root 
of 
Difference. 
h. 
m. 
s. 
4 
19 
30 
•897 
•9471 
4 
24 
30 
•900 
•9487 
4 
29 
30 
•904 
•9508 
4 
34 
30 
•906 
•9518 
4 
39 
30 
•908 
•9529 
4 
44 
30 
•908 
•9529 
4 
49 
30 
•909 
•9534 
4 
54 
30 
•910 
•9539 
4 
59 
30 
•910 
•9539 
Mean 
•95171 
The whole time of deposit was 2700 seconds, but from this a deduction has to be made 
for the time lost in operating the reversing key. The loss of time at each operation 
was found (by a process already described) to be ‘083 second. Thus the actual time of 
passage of the current through the voltameters is to be taken at 
2700 — 7 X *083 = 2699'4 seconds. 
After the deposits had been formed they were washed in the manner already 
described with alcohol and hot and cold water, soaked over night, then rinsed and set 
to dry at 160° C. In the first row of Table Y. will be found the weights of the bowls 
without deposits; in the second the weights after the deposits had been dried at 
160° C. ; in the third the differences representing the weights of the deposits; in the 
fourth the weights of the bowls after heating for about five minutes nearly to redness 
over an alcohol flame ; and in the fifth the weights of the deposits as determined 
from the previous row. 
Table V.- —Deposits of March 10, 1884. 
Large bowl I. 
Pure nitrate. 
Normal strength. 
Small bowl 11. 
Pure nitrate. 
Double strength. 
Small bowl IN. 
Pure nitrate. 
Normal strength. 
Before deposit. 
80-4490 
17-2985 
21-8789 
After deposit, first weighing 
81-5138 
18-3628 
22-9434 
Gain. 
1-0648 
1 0643 
1-0645 
After strong heating . 
81-5135 
18-3627 
22-9433 
Gain. 
1-0645 
1-0642 
1-0644 
Mean 1'0644 grms. 
To obtain numbers which, though of no absolute significance, allow of the com¬ 
parison of experiments made on different occasions, we may divide '95171 (the square 
3 k 2 
