204 FRICTIONAL ELECTRICITY. 



338. Analogous to Magnetic Induction. We 



must master this subject even at the expense of repetition, 



FIG. 141. 



for induction is the only stepping-stone to an intelligent 

 comprehension of what follows. If an insulated conductor, 

 bearing a number of pith ball (or paper) electroscopes, be 

 brought near an electrified body, C, but not near enough 

 for a spark to pass between them, the pith balls near the 

 ends of the conductor will diverge, showing the presence 

 of uncombined electricity. The pith balls at the middle 

 of the conductor will not diverge, marking thus a neutral 

 line. 



339. Charging a Body by Induction. If the 



polarized conductor be touched with the hand, or other- 

 wise placed in electric communication with the earth, 

 the electricity repelled by C will escape, and the pith balls 

 at B will fall together. The electricity at the other end 

 will be held by the mutual attraction between it and its 

 opposite kind at C. The line of communication with the 

 ground being broken, and the conductor then removed 

 from the vicinity of C, it will be found charged with elec- 



