432 Scientific Intelligence, 
The method adopted by the authors for the solution of this problem 
was as follows. When a quantity of electricity # accumulated upon an 
insulated conductor is discharged to the earth through the wire of a gal- 
vanometer, it exerts during its passage a moment of rotation upon the 
eedle. If the time of discharge be so increased, by introducing a column 
of water, that no discharge takes place between the windin ngs of the wire, 
* this “er will still be only a very small fraction of the time of vibration - 
of the needle. The action of the discharge upon the needle may there- 
elongation of the needle after the i ey the angular velocity comm: 
nicated to the needle may be determined by the laws of vibration, oa 
this “+ peel velocity will depend only on the quantity of electricity Z. 
ith a constant current we may communicate a similar influence to 
the needle of "the same galvanometer, if we allow the current to act only 
. avery short time. The same quantity of electricity flows re h the 
conductor in the time ¢ with the intensity ¢ as in the time —~ t with the 
greater intensity ni. Hence in this case also the angular locity of “ 
needle and consequently its elongation depends simply on 
oe which flows through a section of the wire during wre passage 
e curr 
so electricity, and at another by a ~—* current of short duration, 
i +z 
With these premises the solution of the problem rests on the two follow- 
ing points : 
1, To measure the quantity of slactoiolty E in the given electrostatic 
measure, and to observe the elongation of the needle of a neem 
To determine the short time t during which a constant current of 
eng res’ to the second point, no particular experiments are required 
to ih ope since the oe of t ak be jemi ed by calculation 
from the number and Cichinlaias of the windings of the galvanometer, 
from the elongation of the tangent’s-compass during the and 
the intensity of the earth’s magnetism, much more re accurately than 
by direct experiments. The determination of the quantity of 
xperi A large 
“Ss 
at 
i 
B 
g, 
4 
Es 
o 
be! 
(las 
I 
2, 
iously 
mal the pn? part is then Frente teed the a SEH 
to observe its magnetic action ; while the smaller portion is ured by 
balance. 
‘tel Bilge en Bho connected with the earth, was 
Chilis waciirce of electrici By means of a Smec'selectrometer the 
