Engraving by G Gladwin. Joseph Whitworth (1803-1887) established a toolmaking busines in Openshaw, Greater Manchester in 1833, which soon acquired a reputation for high standards of workmanship. He exhibited many tools and machines at the Great Exhibition in London in 1851. Amongst Whitworth's achievements were the devising of a system of precision measurement which, using a precision flat plane and measuring screw, was accurate to a millionth of an inch, and the development of a standard system for screw threads. The latter, which still bears Whitworth's name, was adopted by Britain's railway companies and later became established as a British Standard.
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