[ 4 ° 5 ] 
knob of an uncharged bottle nearly in contaft with 
the brafs ball B. or hang a chain, &c. from theace 
to the table; and, on working the machine, the 
ball D. in the tube becomes entirely enveloped, in 
a denfe, white atmofphere of electricity. If the 
point F. be brought nearly into contact with an 
infulated rubber, and a communication be made 
from the ball B. to the table ; the atmofphere will 
be upon the ball E. in the tube. If a bottle, pofi- 
tively charged, be prefented as in the drawing 
tab. xiv. fig. 9. the appearances in the tube will 
be as therein delineated. But, if a bottle, charged 
negatively, be thus applied, the atmofphere will 
furround the ball E. in the tube, as in tab.xiv. 
fig. 10. 
Conjectures on thefe Phenomena.. 
It is fuppofed, that the impelling power of the 
globe, or the knob of a positively charged bottle , 
drives the particles of electricity through the fub- 
Jlance of the balls , wire, &c. with which they are 
in contaCt, with great velocity, and in a kind of 
ftraight line; but, the eleCtricity having entered 
the vacuum, the repulfion of its particles imme- 
diately takes place, and the tube is inftantly filled 
with light. The denfe white atmofphere upon 
the oppolite ball is fuppofed to proceed from the 
refiftance of the air in the tube ; a fmall portion of 
which, will, in this method of exhauftion, inevi- 
tably remain in it. And, as every particle of elec- 
tricity, is fuppofed to be in a ftate of repulfion 
with refpeCt to its next neighbour, the vacuum 
giving them free liberty of expanding themfelves, 
cr 
