ELECTRIC DISCHARGE WITH THE CHLORIDE OF SILVER BATTERY. 
91 
to draw the paper along the disc, presenting a surface of 1*767 square inch (11‘401 
square centims.) a flat plate laid on the paper required to be loaded, in order to indicate 
the respective pulls, to 5,200 grains when the point was positive, and 8,900 grains 
when negative. This strong adhesion arose evidently from the charging up of the 
upper surface of the paper with the opposite electricity to that of the disc, and hence 
it appeared probable that by making the paper thoroughly dry the upper surface 
ought to take a higher charge and cause a stronger adhesion, and this was found to be 
the case. 
In order to measure the force of adhesion when the paper was well dried, we had 
successively made two new dynamometers, as the first only ranged to 4000 grains ; 
the pull so much exceeded our anticipations, that the second — from 3000 to 10,000 
grains — was found to be insufficient. Ultimately, one ranging from 10,000 to 50,000 
grains was employed. The strain required to pull away the paper was — 
With the point negative, 30,000 grains. 
„ positive, 18,000 „ 
These strains were reproduced when the paper was under the pressure of 129,690 
grains (8403'8 grms.) and 53,530 grains (3468 ‘6 grms.) respectively. On the hypo- 
thesis of two parallel plates (the upper surface of the paper and the disc-terminal) 
each of area (A) = 11 -401 square centims., at a distance (D) = 0‘01079 centim., the 
thickness of the paper, between which there is a force of attraction (F) = (gW) = 
8403"8 grms. X 981 and 3468’6grms. X 981 in the several cases, we have the following 
values for the difference of potential (V) between the two planes : — 
F = g W = 
A 
V 2 
8 77 I) 2 
8 77 g W 
whence, V = D 
or, when the point was negative — 
8 X 3-14159 X 981 X 8403'8 ^ AoAK . 4 
= 46-0205 electro-static units. 
V = 0-01079 */ 
11-401 
= 46-0205 X 
3 X 10 10 
10 8 
= 13,806-15 volts. 
and, when the point was positive — 
8 X 3-14159 X 981 X 3468’6 
V 0-01079 y 
= 29‘5663 X 
11-401 
3 X 10 10 
= 29-5563 electro-static units. 
10 8 
N 2 
= 8869*89 volts. 
