We now need to 'harvest' the electricity and take it to the battery using wires. The coil can't just be connected directly to the battery because as the armature turns, the wires would quickly become twisted. In addition, to charge a battery we need direct current rather than alternating current.

One answer would be to use a rectifier. Rectifiers need special materials, so on the island we used a commutator to produce a direct current.

How can we take electricity from the generator?

In order to take electricity from the generator we need to use a type of sliding connection.

By connecting the sliding connection brushes to each end of the coil in turn we capture a direct current as the armature turns.

Getting current into the battery 

Major funding for Rough Science was provided by the National Science Foundation. Corporate funding was provided by Subaru.

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