406 Mr. Nicholson’s Defcription of 
revolution, we Shall find that the electric States of the respec- 
tive maffes have been greatly increafed : for the ninety-nine 
parts in A and in B remain, and the one part of eleCtricity in 
C has been increafed fo as nearly to compenfate ninety- nine 
parts of the oppofite eleCtricity in the revolving plate B, while 
the communication produced an equal mutation in the electri- 
city of the ball. A Second rotation will, of courfe, produce 
a proportional augmentation of thefe increafed quantities ; and 
a continuance of turning will foon bring the intensities to their 
maximum, which is limited by an explofion between the 
plates. 
If one of the parts be connected with an electrometer, more 
efpecially that of Bennet, thefe effects will be very clearly feen* 
The fpark is ufually produced by a number of turns between 
eleven and twenty ; and the electrometer is fenfibly acted upon 
by Bill fewer. When one of the parts is occasionally con<- 
neCted with the earth, or when the adjustment- of the plates 
is altered, there are fome variations in the effeCus, not difficult 
to be reduced to the general principles, but fufficiently curious 
to excite the meditations of perfons the moft experienced in 
this branch of natural philofophy. An. attention to brevity, 
however, renders it neceffiiry to forbear enlarging upon them. 
If the ball be connected with the lower part of Bennet’s 
electrometer, and the plate A with the upper part, and any 
weak eleCtricity be communicated to the electrometer, while 
the poSition of the apparatus is fuch that the crofs- piece GH 
touches the two pins ; a very few turns will render it percep- 
tible. But here, as well as in the common doubler, the effeCt 
is rendered uncertain by the condition, that the communicated 
eleCtricity rauft be Strong enough to deftroy and predominate 
J over. 
