science · 13 July 1880 · 144 years ago
In 1880, Stephen D. Field of New York City was issued a U.S. patent for "propelling railway cars by electromagnetism" (No. 229,991). When he first used it on a street car in an electric street car in 1874, his inntion was the first electric streetcar to run successfully with current generated by a stationary dynamo. The current was conveyed by one of the rails, via a metal wheel to the onboard motor, and returned through a second metal wheel to the other rail. Field first filed for a caveat on 21 May 1879, and when issued, the patent protected his claim for this system of supplying electric power through the rails and to the motor.
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