118 rerPortT—1 890. 
Interval between 0 
Battery and ; = Sak um Ry ; = C2 
Galvanometer Resistance Scale = Correction = 
Gontavts Divisions 2 Cy 
0 seconds 275,980 0 1/0734 0 10734 
a 275,180 2b 1:0765 —‘0082 1:0733 
30 . 271 380 14:5 1:0916 — 0184 1:07382 
60 a5 267,180 22°5 1/1088 —'0286 1:0802 
5 + 91,370 5 4:3223 ‘0168 4:3391 
30 an 92,670 22 4:2617 ‘0743 4-3360 
60 ss 94,170 42 41938 “1415 4°3353 
The last three lines of the table give the results of a series of com- 
parisons between II., which had a leak, and a condenser of ‘1 microfarad, 
which showed absorption. ‘lhe resistance with II. was 394,930 ohms. 
In the first four lines the corrections are negative, for the capacity of 
the leaky condenser is being found in terms of the standard. In the next 
three lines they are positive, for the ratio of the mica condenser to the 
leaky standard II. is being found. 
A comparison of the fourth and sixth columns shows the results of 
the correction. In the fourth line it is clear that the correction is not 
large enough. This probably arises from the difficulty of making contact 
with the galvanometer circuit sufficiently soon after the battery is broken 
to insure that the whole of the charge accumulated by the leak should 
pass throngh the galvanometer. 
The leak correction was also tested with similar results by putting an 
artificial leak in I. 
We will now give some specimens of the observations made to com- 
pare I. with a mica condenser in order to show the accuracy attained. 
Condenser I. compared with ‘1 microfarad ; resistance with L., 493,560 
ohms; resistance with ‘1 microfarad, 105,800 + a variable resistance 
given below. 
In the table in which the effect of the galvanometer is shown by the 
letters R, L,in the last column, R means there was a deflection to the 
right, L to the left. 
Interval between Galvano- Variable Resistance to be 
meter and Battery Contact added above Effect on Galvanometer 
{ 700 R 
5 seconds 400 Ti 
( 500 , very small R 
400 L 
a ong {700 R 
600 L 
( 1200 L 
0 » 1300 Tremor L, then swing to R 
\ 1400 R 
Thus in this case the effect of an alteration of 100 in the resistance, 
a.€. y>oo Of the whole, is very marked, and we may take the following 
values for R: — 
5 seconds interval . : . . 105,800 + 500 
2 q : : . 105,800 + 650 
ire ee ee he Oo OS a aera 
