SIMPLE ELECTROSCOPE.

Drive the eye of a needle into a cork and stop a bottle with it, the

point being up. At the balancing-spot of an eagle’s feather glue a

little hard socket or cup of glass or metal, and place it on the needle

point.

Sealing wax, a vulcanite comb passed rapidly through the hair, or other

“excited” electrifier, will cause the feather to whirl round and follow

it as iron will the magnet.

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