616 
MR. J. HOPKINSON ON THE 
only a portion are used. The values of 4/(5) and -4/(10), for glasses 2 and 7 respectively, 
are taken as sensibly equal to B, and are calculated on the assumption that during the 
short time of insulation the rate of loss at any instant is proportional to the then charge. 
The values of 4/(1) — B and 4/(5) — B are deduced as though^ were constant during 
the time of insulation, and are therefore considerably below the truth in all cases. It 
will be observed that the battery was not quite constant ; but the value of 48 elements 
may be taken as 3160 scale-divisions without serious error. 
Glass No. 2. — Temperature 53°. It was roughly estimated that on insulation \ of 
the charge was lost within 1 second. Notwithstanding this high conductivity, the 
residual charge was capable of rising to more than 400 scale-divisions when the flask 
had been charged with 48 elements and then discharged for a few seconds. This 
differentiates the polarization in even highly conductive glass from the electrochemical 
polarization in a voltameter, in a single element of which no electromotive force can 
give rise to a return force greater than that due to the energy of combination of the 
constituents of the electrolyte. Subsequently, considerable residual charges were 
obtained with the same glass up to 150°; at 180° the residual charge was so rapidly 
lost that it was hardly sensible. 
h. 
m. 
Temperature 39-|°. 
Time 6 
10. 
Charged with 7 elements. 
6 
11. 
From 462 to 350 in 2 seconds. 
6 
12. 
„ 463 to 360 „ „ 
6 
17. 
„ 464 to 350 „ „ 
6 
19. 
,, 464 to 350 „ „ 
B=1<M) 1 at 394° 
Log B= 1-0 f at 6 * 
6 
20. 
Charged with 48 elements. 
Temperature 41°. 
6 
40. 
Discharge. 
6 
41. 
50 in 4 seconds. 
6 
42. 
CO 
CM 
6 
43. 
18 „ „ 
Temperature 41°. 
4/(1)— B=0-24 at 41°. 
