: C 35 2 ] 
charg’d phial, the balls will be affedled in the fame 
manner at the approach of excited wax, or the wire 
of the phial. 
Experiment 4. 
Electrify the cork- balls as in the laft experiment 
by glafs ; and at the approach of an excited flick of 
wax their repulfion will be incrcafed. The effedit 
will be the fame, if the excited glafs be brought to- 
wards them, when they have been electrified by wax. 
The bringing the excited glafs to the end, or edge 
of the tin-tube, in the third experiment, is fuppos’d 
to electrify it pofitively, or to add to the eledtrical 
fire it before contained ; and therefore fome will be 
running off through the balls, and they will repel 
each other. But at the approach of excited glafs, 
which likewife emits the eledtrical fluid, the difcharge 
of it from the balls will be diminifh’d ; or part will 
be driven back, by a force adting in a contrary di- 
rection ; and they will come nearer together. If the 
tube be held at luch a diflance from the balls, that 
the excefs of the denfity of the fluid round about 
them, above the common quantity in air, be equal to 
the excefs of the denfity of that within them, above 
the common quantity contain’d in cork; their repul- 
fion will be quite deflroy’d. But if the tube be 
brought nearer; the fluid without, being more denfe 
than that within the balls, it will be attradled by 
them, and they will recede from each other again. 
When the apparatus has loft part of its natural 
fhare of this fluid, by the approach of excited wax to 
one end of it, or is eledtrified negatively ; the eledtrical 
fire 
