[ 35 6 J 
be carried off thro’ the columns of mercury ; but, as 
the tube is withdrawn, the fire is fuppofed to return. 
Experiment 9. 
Let an excited flick of wax, of two feet and 
an half in length, and about an inch in diameter, 
be held near its middle. Excite the glafs tube, and 
draw it over one half of it ; then, turning it a little 
about its axis, let the tube be excited again, and 
drawn over the fame half ; and let this operation be 
repeated feveral times : then will that half deftroy 
the repelling power of balls electrified by glafs, and 
the other half will increafe it. 
By this experiment it appears, that wax alfo may 
be electrified pofitively and negatively. And it is pro- 
bable, that all bodies whatfoever may have the quan- 
tity they contain of the eleCtrical fluid, increafed, or 
diminifbed. The clouds, I have obferved, by a great 
number of experiments, to be fome in a pofitive, and 
others in a negative {fate of electricity. For the cork 
balls, electrified by them, will fometimes clofe at the 
approach of excited glafs ; and at other times be fe- 
parated to a greater diflance. And this change I have 
known to happen five or fix times in lefs than half 
an hour j the balls coming together each time, and 
remaining in contaCt a few feconds, before they re- 
pel each other again. It may likewife eafily be dis- 
cover’d, by a charged phial, whether the eleChical 
fire be drawn out of the apparatus by a negative 
cloud, or forced into it by a pofitive one : and by 
whichfoever it be eleClrified, fhould that cloud either 
part with its overplus, or have its deficiency fupplied 
iuddenly, the apparatus will lofe its electricity : which 
2 is 
