[ [26] In Rees, op. cit. (footnote 21), vol. 34 ("Steam Engine"). John Farey was the writer of this article (see Farey, op. cit., p. vi).
Two mechanisms for producing a straight line were introduced before the Boulton and Watt monopoly ended in 1800. Perhaps the first was by Edmund Cartwright (1743-1823), who is said to have had the original idea for a power loom. This geared device (fig. 12), was characterized patronizingly by a contemporary American editor as possessing "as much merit as can possibly be attributed to a gentleman engaged in the pursuit of mechanical studies for his own amusement."[27] Only a few small engines were made under the patent.[28]
[ [27] Emporium of Arts and Sciences, December 1813, new ser., vol. 2, no. 1, p. 81.
[ [28] Farey, op. cit. (footnote 6), p. 666.
Figure 12.—Cartwright's geared straight-line mechanism of about 1800. From Abraham Rees, The Cyclopaedia (London, 1819, "Steam Engine," pl. 5).
The properties of a hypocycloid were recognized by James White, an English engineer, in his geared design which employed a pivot located on the pitch circle of a spur gear revolving inside an internal gear. The diameter of the pitch circle of the spur gear was one-half that of the internal gear, with the result that the pivot, to which the piston rod was connected, traced out a diameter of the large pitch circle (fig. 13). White in 1801 received from Napoleon Bonaparte a medal for this invention when it was exhibited at an industrial exposition in Paris.[29] Some steam engines employing White's mechanism were built, but without conspicuous commercial success. White himself rather agreed that while his invention was "allowed to possess curious properties, and to be a pretty thing, opinions do not all concur in declaring it, essentially and generally, a good thing."[30]
[ [29] H. W. Dickinson, "James White and His 'New Century of Inventions,'" Transactions of the Newcomen Society, 1949-1951, vol. 27, pp. 175-179.
[ [30] James White, A New Century of Inventions, Manchester, 1822, pp. 30-31, 338. A hypocycloidal engine used in Stourbridge, England, is in the Henry Ford Museum.
