William Oughtred

English mathematician (1574–1660)

William Oughtred ( AWT-urd;5 March 1574 – 30 June 1660), also Owtred or Uhtred, was an English mathematician and Anglican clergyman. After John Napier discovered logarithms and Edmund Gunter created the logarithmic scales (lines, or rules) upon which slide rules are based, Oughtred was the first known to use two such scales in separate rods sliding by one another to perform direct multiplication and division. He is credited with being second inventing the slide rule instrument in about 1632.

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