Advantage of elevated pointed Conductors. 833 
to connect the pieces of tin-foil together. The charged 
artificial cloud did not now ftrike to the point until it 
was removed from the ball c to the diftance of four 
inches and a half; it then began to ftrike to it, and con- 
tinued ftriking whilft it was gradually removing fome- 
times to ten inches; but when the point was removed 
beyond the greateft ftriking diftance, the point was not 
luminous as in the laft experiment, except when the ar- 
tificial cloud difcharged its electric fire out into the air, in 
a diverging pencil from the ball c : then it was lumi- 
nous, but at that inftant only. Every time the artificial 
cloud ftruck to the point, the electric fire made a beauti- 
ful appearance in palling off between the feparations of 
the pieces of tin-foil. I then connected all the tin-foil 
on the wax fo as to leave no feparation, then the charged 
artificial cloud would not ftrike to the point at any 
diftance. 
EXPERIMENT XII. 
« ' • l " '■ * j . , ’ • 1. .... '.'l ! ; 
I placed the rod d, with the four-inch ball at the end 
as in the firft experiment, this I put on a glafs pillar to 
infulate it; then from the rod I made a communication 
to the earth, with about three feet of filver wire, which 
was only ^th part of an inch diameter : on charging 
Vol. LXVIII. 5 L the 
