But the mule was more than a combination of the jenny and the rollers; although this in itself was an important development in spinning. As just mentioned, with the mule method of spinning, the roving was first passed between rollers and so partly attenuated. When the required length had passed between them, they stopped, and thus acted like the clasp arrangement on the movable carriage of the jenny. But whereas, in the jenny, the spindles were fixed in the frame, in the mule they were fixed in the movable carriage, which receded from the rollers as the partly attenuated roving was given out, and continued to recede when the rollers stopped, thus attenuating it still more, while at the same time the spindles were revolved to give the required twist to the thread. Then, as in the jenny, the carriage was moved back to its first position, and the spindles were again revolved to wind the spun thread on to them. The important thing about the “stretch” in the machine invented by Crompton was that he “made the spindles recede from the rollers in such a way that the yarn was subjected to the least possible strain until it had been strengthened by twisting or spinning. As a result the yarn produced by the ‘mule’ was more even and smooth, and could be spun thinner or of higher ‘counts’ than had been possible on any earlier machines.”[365] [Footnote 365: _Souvenir of Royal Visit to Bolton_, p. 21.] If ever the labours of anyone have deserved the grant of a patent, surely it was so in the case of Crompton. Even though his machine was based upon the jenny and the rollers, it marked an immense advance in the development of spinning machinery. Usually it is surmised that he did not obtain a patent owing to lack of funds. Probably it was much more due to his lack of the business qualities which Arkwright possessed in abundance, coupled with difficulties connected with the character of the machine, and with the views regarding patents prevalent at the time.