Robert Davidson

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Robert Davidson (1804 - 1894) was a Scottish inventor who built the first known electric locomotive in 1837. Born and died in Aberdeen, northeast Scotland, where he was a prosperous chemist and dyer, amongst other ventures. Davidson was educated at Marischal College, where he studied for one year on a scholarship - he had an education in return for being a lab assistant. He became interested in the new electrical technologies of the day. From 1837 he made small electric motors on his own principles, though William H. Taylor in the U.S. made similar motors from 1838. Both men worked independently, without knowledge of the other's work.

Davidson staged an exhibition of electrical machinery at Edinburgh, Scotland in 1840, and later at the Egyptian Hall in Piccadilly in London. Amongst the machines shown were electrically operated lathes and printing presses. His electric railway locomotive was tested on the Edinburgh-Glasgow line in 1842. The first known working electric locomotive was made in New England, but this was only a working model. On October 4th, 1835, this model was demonstrated at Troy, New York by its inventor Thomas Davenport.

Davidson made a model electric locomotive in 1837. His 'Galvani' of 1842 was a four-wheeled machine, powered by zinc-acid batteries. It was capable of carrying itself at 4mph. It did not haul any passengers or goods.

In a later report it was calculated that consuming zinc in a battery was forty times more expensive than burning coal in a firebox. Later experiments in America proved these figures correct. Battery powered locomotives were not economically viable, a point lost on some steam engineers who smashed the 'Galvani' in its shed, fearing the potential competition to their new trade. Financially viable electric traction was developed from the 1860s when the dynamo was invented and perfected. Davidson lived to see these developments - his reaction to the opening of the City & South London Tube was to commission a new set of business cards, that read 'Robert Davidson : Father of the Electric Locomotive'.

[edit] Sources

• The Practical Mechanic Vol II, November 1842 pp 48-51.
• 'A Note on Electro-Magnetic Engines' J.H.R Body, Newcomen Society Transactions Vol 14 pp103-107.
• 'Electro-Magnetism and Motive Power:Robert Davidson's "Galvani" of 1842' Robert C.Post Railroad History 1974 pp5-23.
• 'An Ingenious Aberdonian' A.C Davidson Scots Magazine January 1976
• article by A.F Anderson 'New Scientist, 11 June 1981 pp 712-713.