[ 39 § ] 
driven from it ; being often blown upon the ball A, 
fo as to blacken it with the fmoak. Then charge 
the phial negatively, and (the apparatus remaining 
as before) apply the knob of the phial as at firft; 
and you will then perceive the flame to be blown 
quite in the contrary diredtion, viz. from A to- 
wards, and often upon B, as upon Dr. frank- 
lin’s principles of theLeyden bottle, it ought to be. 
Obferve that, in this experiment it is neceftary to ufe 
the lead: charge that can be given, juft fufficient 
to leap the interruption in the circuit; which ex- 
perience will presently determine; for if the 
charge be too great, the flame will be attradted as 
well as repelled, in the difcharge of the phial; and 
then, nothing can be infered from the experiment. 
EXPERIMENT II. 
Charge a large jar pofitively , and infulate 
it; then take a long curved wire, pointed , at 
both ends , and hold it by a glafs handle, fo as to 
bring one end of the wire, half an inch, from the 
knob, and the other end of it, to the fame diftance, 
from, the coating of the jar. You will then obferve 
a frnall luminous fpark, upon the point appofed to 
the knob of the jar, and a fine pencil, diverging 
from the lower point, fpreading upon the coating 
of the jar, which will prefently difcharge it filently. 
Then charge your jar negatively ; infulate it, and 
apply the wire as before ; and the appearances, at 
the points of the wire, will be diredtly reverfed; 
plainly demonftrating the diredtion of the eledtri- 
oity in the difcharge of the bottle. 
Another 
