. . . "M.P.W. Boulton in 1868" . . . . . . . "1820" . . . . . . "an earlier patent from 1868" . "M. P. W. Bolton" . . . . . . . . . . "1894" . . . "1820-09-22" . "1894-06-30" . "M. P. W. Boulton" . . . . . . . . . . . . "Matthew Piers Watt Boulton" . "M.P.W. Boulton" . "a British inventor" . . . . . "Matthew Piers Watt Boulton#Family life" . . "Matthew Piers Watt Boulton" . . . .