James Fox was the founder of a well-known firm of machine-tool builders in Derby. He was originally a butler, but his mechanical skill turned him toward the design and building of lace machinery. The gentleman in whose employ he had served furnished him with the means of beginning business on his own account, and he soon obtained work from the great firms of Arkwright and Strutt, the founders of modern cotton manufacture. His planer, built about 1814, was used in the manufacture of this machinery. It is described by Samuel Hall, a former workman under Fox, as follows: “It was essentially the same in principle as the planing machine now in general use, although differing in detail. It had a self-acting ratchet motion for moving the slides of a compound slide-rest, and a self-acting reversing tackle, consisting of three bevel wheels, one a stud, one loose on the driving shaft, and another on a socket, with a pinion on the opposite end of the driving shaft running on the socket. The other end was the place for the driving pulley. A clutch-box was placed between the two opposite wheels, which was made to slide on a feather, so that by means of another shaft containing levers and a tumbling ball, the box on reversing was carried from one bevel-wheel to the opposite one.”[54] This planer was in regular use as late as 1859. The driving and reversing mechanism described above is almost exactly that used on Clement’s great planer, built a dozen years later. Fox is said to have also invented a screw-cutting machine, an automatic gear cutter and a self-acting lathe, but the evidence in regard to their dates is uncertain. [54] _Ibid._, p. 315. George Rennie was the brother of Sir John Rennie. They succeeded to the business founded by their father, the elder John Rennie, one of Watt’s best-known workmen and next to Murdock the most important of his assistants, who built the Albion Flour Mills in Black Friars, where one of the first rotative engines was installed about 1788. The mill was a great success until it burned down a few years later. John Rennie’s connection with it established his reputation and he shortly after started out for himself as a millwright and founded the business which his two sons carried on for many years and which had a great influence throughout all England. Sir William Fairbairn was one of those who worked for George Rennie and furnishes another example of the cumulative influence of a succession of strong mechanics.