580 
MESSRS. R T. GLAZEBROOK AND S. SKINNER ON THE 
The current lasted, in the first instance, for 25 minutes, and in the second, for 
5 minutes 45 seconds, thus we have for T the value 1845 seconds. 
The value of W — Y was 1176 for 25 minutes, 1238 for 2 - 5 minutes, and 1233 for 
3'25 minutes. 
From these we obtain, as the mean value of AY — Y, 11 87, and hence A" = 4568. 
The fact that there was a break in the middle so that four readings of the 
chronometer are involved, renders the time measurement less trustworthy than in the 
other experiments. 
Bowls I. and IY. were used. 
Experiment 7, August 12, afternoon. 
AY changed from 5753 to 5756 during the experiment, the mean value was 5754‘5. 
The value of AY — Y was changed after the current had been passing for 5 minutes 
from 3349 to 3344, but without breaking the current, the slide being readjusted 
to suit. It remained very steady at this value while the experiment lasted. The 
whole time of the experiment was 50 minutes 5 seconds. 
Thus the mean value of AY — Y is 3344'5, therefore 
V = 2410. 
Bowls III. and Y. were used. 
Experiment 8, August 14, morning. 
The value of AY changed from 5738 to 5737 ; mean value, 5737'5. The value 
of AY — Y was steady all the time at 1120, and the slide was very little altered ; thus 
the current was very steady, and we have 
V = 4617-5. 
Bowls I. and IY. were used. 
Experiment 9, August 14, afternoon. 
The value of AY changed from 5730 to 5729’5 ; mean value, 5729'S. The current 
ran for 1 hour and 5 seconds. 
The values of AY — V were 3290 for 6 minutes, then 3288 for 26 minutes, changing 
during the next minute to 3280, and after that being steady at 3280 ; for the remaining 
27 minutes the current was not broken, but the slide of the rheostat was altered as the 
resistances were changed. From this we have as the mean value of AY — Y, 3284-5, 
whence 
V = 2445-3. 
Bowls III. and Ah were used. 
It should be noticed, in the cases in which the current varied, that an accurate 
value of the time at which the changes in the position of the slide took place, is not 
needed, provided the whole time is known accurately. 
These are all the experiments made. 
