Trolley pole

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 the electric traction motors of a tram or trolley bus. It is a type of current collector. The use of overhead wire in a system of current collection is reputed to be the 1880 invention of Frank J. Sprague, while the first working trolley pole was developed and demonstrated by Charles Van Depoele, in autumn 1885.

The term "trolley", also used to describe the pole or the passenger car using the trolley pole, is derived from the grooved conductive wheel attached to the end of the pole that "trolls" the overhead wire.

The term "trolley" predates the invention of the trolley pole. The earliest electric cars did not use a pole, but rather a system in which each tramcar dragged behind it an overhead cable connected to a small cart – or "troller" – that rode on a "track" of overhead wires. From the side, the dragging lines made the car seem to be "trolling", as in fishing. If the troller cart were to derail from the overhead wire, it would fall with a loud crash onto the roof of the tramcar and be troublesome to reposition; these drawbacks prompted a search for better ways to connect to the power wire. Later, when a pivoted pole replaced the troller, it came to be known as a "trolley pole".

An early development of an experimental tramway in Toronto, Ontario was built in 1883, having been developed by John Joseph Wright, brother of swindler Whitaker Wright. While Wright may have assisted in the installation of electric railways at the Canadian National Exhibition (CNE), and may even have used a pole system, there is no evidence about this. Likewise, Wright never filed or was issued a patent.

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