born Dec. 21, 1803, Stockport, Cheshire, Eng.
died Jan. 22, 1887, Monte-Carlo, Monaco
British mechanical engineer.
Working for Henry Maudslay , he devised a scraping technique for making a true plane surface. He followed this with a measuring machine and a system of accurate dimensional standards or master gauges to go with it, and screws with standardized threads (1841), among other innovations. His machine tools became internationally known for their accuracy and quality.