Certainly there was faith in the invention, and Paul himself claimed that, in the course of twenty years, he made more than £20,000 out of it as patentee.[249] It was used in at least one factory at London, in one at Birmingham, and in one at Northampton. The machinery at Birmingham was turned by animal-power, and at Northampton by water-power, and at the latter place fifty hands were employed in the factory.[250] It seems evident, however, that, whatever the reason, when the term of the patent expired in 1752 faith in the invention had also largely expired, and Paul attempted to get it introduced into a Foundling Hospital in London.[251] During the next six years he made improvements in the machine, and in 1758 obtained another patent for it, but shortly afterwards he died, and the honour of carrying the use of rollers in spinning to a successful issue was left to others.[252] [Footnote 249: _Ibid._, pp. 256, 268.] [Footnote 250: Baines, _ibid._, p. 134. Espinasse, _ibid._, pp. 349-350.] [Footnote 251: French, _ibid._, p. 266. Espinasse asserts that it was introduced into at least one Yorkshire workhouse (_ibid._, p. 355).] [Footnote 252: French, _ibid._, p. 269.] But it is not only in connection with spinning that Paul’s name has to be remembered. Whatever failings he may have had, he was certainly a man of an inventive turn of mind. It is recorded that in 1742 he granted a licence in consideration of £200, for the right to use a “pinking” machine he had invented.[253] But more important in relation to the cotton industry was his invention of a carding-machine, for which he secured a patent in 1748.[254] Earlier in the same year a man named Daniel Bourne had also taken out a patent for a carding-machine,[255] and after a time the principal processes of the two machines were combined in one machine, though it is to Paul’s invention that the most important method of carding the finer qualities of cotton at the present day is traced.[256] Both these machines, however, were lacking in that they had no “doffing” arrangement, which prevented continuous working, but the deficiency in this respect was afterwards removed by Arkwright with his crank and comb device, while others improved the imperfect feeding arrangement.[257] [Footnote 253: _Ibid._, p. 252.] [Footnote 254: _Ibid._, p. 266. It appears, however, that he may have invented this machine as early as 1740 (_ibid._, 256).] [Footnote 255: Espinasse, _ibid._, p. 365.] [Footnote 256: Dobson, _ibid._, 36-37.] [Footnote 257: Dobson, _ibid._, p. 37.]