("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]

[Footnote 27: _Emporium of Arts and Sciences_, December 1813, new ser.,
vol. 2, no. 1, p. 81.]

[Footnote 28: Farey, _op. cit._ (footnote 6), p. 666.]

[Illustration: 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]

[Footnote 29: H. W. Dickinson, "James White and His 'New Century of
Inventions,'" _Transactions of the Newcomen Society_, 1949-1951, vol.
27, pp. 175-179.]

[Footnote 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.]

[Illustration: Figure 13.--James White's hypocycloidal straight-line
mechanism, about 1800. The fly-weights (at the ends of the diagonal arm)
functioned as a flywheel. From James White, _A New Century of
Inventions_ (Manchester, 1822, pl. 7).]

The first of the non-Watt four-bar linkages ap