460 Mr. swift's Account of form 
From either the prime conductor, or from the anti- 
condudtor, I fufpend a metal ball which can fwing like 
the pendulum of a clock; I then place on a level with it, 
at the diftance of four or five inches from it, another ball 
fixed and connected with the earth ; as foon as the cylin- 
der begins to turn, the fwinging ball begins to be at- 
tracted, and ilrikes with confiderable force againft the 
fixed one, emitting a fpark or fiafh at the fame time. 
In fuch pofition if a point be put the vibrations of the 
fwinging ball will immediately begin to leffen, and it 
foon becomes intirely at reft, no flafh or fpark happen- 
ing from the inftant the point is put there. 
9. On one of the knobs or balls at the end of the pole 
dd, I put a point turned downwards towards the con- 
ductor, and as foon as the cylinder moves it is thrown 
upwards or repelled, and the oppofite knob or ball ad- 
heres to the conductor under it ; but when points are put 
on both knobs and turned downwards or towards the 
conductors, the pole dd will remain unmoved, notwith- 
ftanding all the poflible friction which can be given by 
turning the cylinder. 
10. To render thefe experiments more analogous to 
the natural phenomena of lightning and rain defcending 
from the clouds, I place a veflel of water infulated, and 
as the clouds (fig. 2.) being charged pafs along the 
frame, 
