118 ELEMENTS OF STATIC ELECTRICITY. 



and H, where the charge is received, show only a glow 

 of light. 



These brushes of light always turn in the opjtosite 

 direction to that in which the plate A revolves ; differ- 

 ence of potential between the comb and that portion of 

 the plate approaching it producing attraction ; while 

 equality of potential between the comb and that portion 

 of the plate receding from it produces repulsion. (seep. 224.) 



Following any opposite pair of carriers, as TFand Z, we 

 find that as Z passes under the wire brush _F, W passes 

 under E ; and as Z moves on to the insulated comb 7T, 

 TFat the same instant arrives at L ; but Tf, as already 

 shown, has a higher potential than Z, and, at this point, 

 a peculiar adjustment takes place. W gives up its 

 charge through the comb L, to the inside of the Ley- 

 den jar D. This creates a positive charge on the inside 

 of .Z>, which induces a negative charge on its outside. 

 The electricity thus repelled, passes to the outside of 

 (7, making it positive, and inducing negative on its 

 inside ; and this repelled electricity flows through the 

 comb K to the plate A, as already shown. W then 

 moves down to the uninsulated comb ZT, while Z moves 

 up to V. Each now passes under the wire brush at- 

 tached to its respective comb, and the combs being 

 attached to the brass core at the center of M, the carriers 

 are put in electric connection with each other, and their 

 potential equalized by the flow of the residual charge 

 from If to F", as already described; so that each arrives 

 at the original position of the other at the same poten- 

 tial, ready to repeat the same process. 



It should be noticed, that the residual is slightly in- 

 creased by induction from Tand X, as the carriers move 

 from the combs L and .Zf to the combs JTand F". 



