ELECTRIC DISCHARGE WITH THE CHLORIDE OF SILVER BATTERY. 
85 
Table XII. — Showing the results in volts. 
Curve. 
1000 volts. 
2000 volts. 
3000 volts. 
4000 volts. 
5000 volts. 
6000 volts. 
7000 volts. 
8000 volts. 
inch. 
inch. 
inch. 
inch. 
inch. 
inch. 
inch. 
inch. 
XII. Mean . . 
0-0049 
0 021 
0-053 
0-097 
0-150 
0-210 
0 273 
0-335 
XI la. Theoretical 
0-0052 
0-021 
0 047 
0-083 
0-130 
0-187 
0-255 
0-330 
It will be seen from the above that curve XII., Plate 8, laid down from the means 
of all the observations, accords very closely with curve Xlla, Plate 8, drawn on the 
hypothesis that the striking distance between a point and a plate is in the ratio of the 
square of the number of cells, as we stated to be the case in a previous communication/'' 
It would, however, appear that there is a tendency in the curve to converge towards 
the theoretical curve as the battery is increased beyond a certain number of cells ; 
and, therefore, it is possible that the law of the squares may not hold for very high 
numbers ; at about 4000 to 5000 cells the curve diverges from the theoretical curve, 
but it approaches it again in the majority of cases beyond that number up to 8040 cells. 
With two points the length of spark is greater for high potentials, 5400 to 8040 
cells, than between a point and disc, but not for low potentials, as will be seen from 
the following numbers laid down in curve XV., plate 8 : — 
Table XIII. — Length of spark between two paraboloidal points. 
1080 cells. 2160 cells. 4320 cells. 4320 cells. 6400 cells. 6480 cells. 7560 cells. 8040 cells. 
Curve. inch. inch. inch. inch. inch. inch. inch. inch. 
XV. 0-005 0-024 0-0614 0-1307 0-2287 0-2895 0-3620 0-401 
By laying down a smooth curve, XVa, fig. 15, through the observed distances in 
curve XV., we have obtained the numbers given in Table XIII A for multiples of 
1000 cells ; the second line shows the lengths of spark on the hypothesis of their being 
in the ratio of the squares of the number cells. 
Table XIIIa. — Length of spark between two paraboloidal points. 
Curve. 
1000 cells. 
2000 cells. 
3000 cells. 
4000 cells. 
5000 cells. 
6000 cells. 
7000 cells. 
8000 cells. 
inch. 
inch. 
inch. 
inch. 
inch. 
inch. 
inch. 
inch. 
XVa. 
0 005 
0 021 
0-053 
o-no 
0-178 
0-249 
0 324 
0-401 
Theoretical 
0-0062 
0-0251 
0-0564 
0-1002 
0-1566 
0-2255 
0-307 
0-401 
In order to show at a glance the relative striking distances between two spherical 
and two plane surfaces, two concentric cylinders, a point and a disc, and two points, 
we laid down on the same scale curves VIII., X., XI., XII., and XVa ; the diagram, 
fig. 15, is a pantagraphic reduction of them to one third of the originals. 
W e may, however, state that we place greater reliance on the measurements of the 
length of spark up to that for 2000 cells between spherical surfaces than between 
Proc. Roy. Soc., vol. xxiv. p. 168. 
