the Electrical Charge of the Prime Conductor of a Machine. 455 
Experiment III. 
10 revolutions, performed in 50 seconds, produced a discharge 
of *41; and 20 revolutions, in 25 seconds, produced nearly the 
same discharge. . 
Here 10 x 50=20 x 25=500. 
Now, assuming that the quantity of electricity generated is in 
proportion to the number of revolutions of the machine, then it 
follows that a certain quantity of electricity, acting for 50 
seconds, produces the same (or nearly the same) discharge as a 
double quantity of electricity acting for half the time; and so 
on, similarly to the results of the other experiments. 
If ¢ be put for the quantity of electricity generated in ¢ seconds, 
and e, for the quantity generated in ¢, seconds, then for equal 
amounts of discharge we shall have 
ext=e, Xt; 
that is, for equal amounts of discharge the quantities of electricity 
are in the inverse ratio of the times. 
In Experiment III. the angular velocities of the machine are 
as 1 : 4, and therefore the intensities of the electricity generated 
would be in the same ratio, provided that no electricity had been 
carried off by the discharge of the liquid; but the deflections 
of Henley’s electrometer dicated that the ratio of the itensi- 
ties of the electricity in the two states of the conductor was only 
about 2 to 3. 
Although equal volumes of water are discharged, we cannot 
infer that the dynamic effects are equal; for the liquids are re- 
spectively discharged with different velocities. 
Let & = the cubic inches of water discharged in each case, w 
~ being its weight in units of lbs. 
n = the corresponding number of revolutions in ¢ seconds 
in the one case, e being the amount of electricity 
generated, and v the velocity with which the liquid 
is discharged. 
n, = the corresponding number of revolutions in ¢, seconds 
in the other case, e, being the quantity of electricity 
generated, and v, the velocity with which the liquid 
is discharged. 
u, U,= the accumulated work or dynamic effect in each case 
respectively. 
vw 
v 
Then v= Wg? and u, = —— ; 
