a Doubler of Rletf-r icily, 29 r 
gold of the eledtro meter be made to diverge to a certain diltance 
by tire above procefs, that diftance will be nearly doubled by ' 
repeating the operation. Another proof of this duplicate 
accumulation is, that, when the third plate is applied to the 
firft, the divergency of the leat gold is apparently undimi- 
ni died, though in this fituation their electricity is dittuied over 
double the quantity of furface. 
That flame will collect electricity better than points was 
mentioned in my former Paper, and is very evident if two 
phials of equal capacity are expofed to the air, the one fur- 
nifhed with a (harp point, and the other having its knob applied 
to an infulated flame, and their electricity afterwards examined 
by the doubler. 
If the weather be rainy, an infulated umbrella may be carried 
in one hand, and the knob of the phial applied to the upper and 
infulated part of the handle; and if it rains fo flow ly as not 
lufficiently to communicate electricity to the umbrella, a torch 
is carried under the umbrella, and ufed as deferibed above. 
It is obvious that fome caution is neceflary in managing ex- 
periments of fo much nicety, Alice,, by the lead: friction of the 
hand on the varnifhed lides of the plates or infulating handles, 
or if the metallic tide of one plate be accidentally rubbed 
againfl: the varnifhed fide of the other, fome degree of electri- 
city is produced, which, becoming fenfible by the operation of 
doubling, may render the experiments equivocal. 
To obviate thefe inconveniencies, I join a conducting handle, 
by means of an infulating nut, to each of the plates. This 
handle confifls of turned unbaked mahogany, about three 
inches long, into one end of which is infer ted a nut of baked 
wood, about half an inch long, covered with fealing-wax, 
upon the other end of which nut the brafs focket of the plate 
is fixed ; by this means it is not neceflary to touch the fealing- 
wax 
