Obfervations in Eleclriciiy. ioi 
electricity from the upper ring of coating on the outfide 
of the jar) and a fine flxeam or pencil of rays will at the 
fame time fly off, beautifully diverging from the lower 
point of the wire f upon the bottom ring of coating on 
the jar. When thefe appearances ceafe, which they will 
as foon as the jar becomes charged, let a pointed wire be 
prefented towards the prime conductor; this will foon 
difcharge the jar filently, during which the lower point 
of the wire f will be illumined with the fmall fpark, 
while the upper point of the wire will throw off a fine 
pencil of rays, diverging towards the upper ring of coat- 
ing, to which it Hands contiguous, as upon Dr. frank- 
lin’s hypothefis it ought to do. A wire of the fame form 
as that marked f may be inferted on a fmall eleCtric Hand, 
fitted by a proper bafe to the bottom of the jar on the 
infide ; this will fhew the appearances when the jar is . 
charged negatively. 
1 he fame experiment may be very conveniently made _ 
with a large pane of crown glafs ^ coated in two places 
at a proper diftance from each other (fig. 2 .) leaving a 
fufficient quantity of glafs uncovered quite round the 
two coatings. This coated plate of glafs fhould be fixed 
in a frame, and mounted upon a proper eleCtric ft and. 
Another Hand of glafs or fealing wax fhould be provided* 
(g) Mine is eighteen inches by fourteen inches. 
to 
