FORCE OF THE WESTON NORMAL CELL IN SEMI-ABSOLUTE VOLTS. 
189 
Table XIX. 
Position I. 
Position II. 
Position III. 
Position IV. 
Mean S. 
(a) 84-708 
•705 
(b) 84-586 
•587 
(c) 84-608 
•602 
(d) 84-720 
•726 
84-656 
84-655 
(b) 84-702 
•70S 
| -586 
•610 
• 722 
84 656 
(i) 84-716 
•714 
•703 
(/) 84-586 
•594 
•592 
(g) 84-608 
•608 
(h) 84-720 
•714 
84 657 
84-657 
84-656* 
84'708 0 
84-588 5 
84-607 2 
84-720 4 
84656 0 
(f) The Evaluation of Corrections. 
It is necessary to apply several further corrections to this value of S. 
The following table contains data omitted above :— 
Table XX. 
The positions 
in the order given in 
Table XVIII. 
Average temperature of 
the scales. 
Average temperature of 
the dynamometer. 
°C. 
• C. 
Position I. 
20-3 
21-5 
„ II. 
19-5 
20-9 
„ HI . 
20-0 
20-3 
„ iv. 
20-8 
20-6 
„ I. 
20-7 
20-7 
„ I. 
20-2 
20-8 
„ II . 
20-5 
20-0 
„ HI . 
20-2 
20-2 
„ IV. 
20-4 
20-9 
Means . . . 
20-3 
20-7 
(1) Temperature Correction. —The average dynamometer temperature was 20°'7 C. 
If d were kept at 12'4448 cm. and the temperature reduced to 20°’0 C. the radius 
would be decreased 0'0013 per cent, and a single deflection would be increased, 
therefore, by 0‘005 per cent, which would amount to a correction of +0‘0008 cm. in S. 
(2) Calibration for the Scales. —Each scale was compared with the standard scale 
described in § YI. (c) at the actual marks where deflection observations were taken. 
* The mean values for III. and IV. are used in calculating this figure. 
