(C) Touch I T to discharge it, and note the action of L.
204. Discussion. No explanation should be necessary for this. Are the leaves charged alike? As they were charged by contact, is the electrification on them + or -?
EXPERIMENT 94. To charge the leaf electroscope by induction.
Apparatus. Our electroscope ([Fig. 57], [§ 202]); ebonite sheet, E S (No. 27); flannel cloth, F C (No. 30).
205. Directions. (A) Charge E S with F C, then hold E S above I T ([Fig. 57]), their surfaces being kept parallel and about 2 or 3 inches apart. Watch the leaves.
(B) Withdraw E S. Do the leaves remain spread?
(C) Repeat (A), and before removing E S, touch I T.
(D) Remove your finger from I T, then withdraw E S. Do the leaves now remain spread?
206. Discussion. The permanent divergence of L was due to a charge given by induction. ([Exp. 76].) As E S was -, what was the kind of a charge in L? Did any electrification go to the electroscope from E S? In (C) what became of the charge in L? Explain why[79] the leaves again diverged in (D). The electroscope was charged with + electrification by taking - out of it.