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Trolley pole
device allowing a tram or bus to collect current from overhead wires / From Wikipedia, the free encyclopedia
A trolley pole is a tapered cylindrical pole of wood or metal, used to transfer electricity from a "live" overhead wire to the control and propulsion equipment of a tram or trolley bus. The use of overhead wire in a railway electrification system is said to be the 1880 invention of Frank J. Sprague.[1]
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