Joseph Whitworth by Samuel Smiles
See Joseph Whitworth
Mr. Whitworth is another of the first-class tool-makers of Manchester who has turned to excellent account his training in the workshops of Maudslay and Clement. He has carried fully out the system of uniformity in Screw Threads which they initiated; and he has still further improved the mechanism of the planing machine, enabling it to work both backwards and forwards by means of a screw and roller motion. His "Jim Crow Machine," so called from its peculiar motion in reversing itself and working both ways, is an extremely beautiful tool, adapted alike for horizontal, vertical, or angular motions. The minute accuracy of Mr. Whitworth's machines is not the least of their merits; and nothing will satisfy him short of perfect truth.
At the meeting of the Institute of Mechanical Engineers at Glasgow in 1856 he read a paper on the essential importance of possessing a true plane as a standard of reference in mechanical constructions, and he described elaborately the true method of securing it,--namely, by scraping, instead of by the ordinary process of grinding. At the same meeting he exhibited a machine of his invention by which he stated that a difference of the millionth part of an inch in length could at once be detected. He also there urged his favourite idea of uniformity, and proper gradations of size of parts, in all the various branches of the mechanical arts, as a chief means towards economy of production - a principle, as he showed, capable of very extensive application. To show the progress of tools and machinery in his own time, Mr. Whitworth cited the fact that thirty years since the cost of labour for making a surface of cast-iron true - one of the most important operations in mechanics - by chipping and filing by the hand, was 12s. a square foot; whereas it is now done by the planing machine at a cost for labour of less than a penny. Then in machinery, pieces of 74 reed printing-cotton cloth of 29 yards each could not be produced at less cost than 30s. 6d. per piece; whereas the same description is now sold for 3s. 9d. Mr. Whitworth has been among the most effective workers in this field of improvement, his tools taking the first place in point of speed, accuracy, and finish of work, in which respects they challenge competition with the world. Mr. Whitworth has of late years been applying himself with his accustomed ardour to the development of the powers of rifled guns and projectiles,--a branch of mechanical science in which he confessedly holds a foremost place, and in perfecting which he is still occupied.
See Also
Sources of Information
- Industrial Biography by Samuel Smiles. Chapter XIV (edited)