Most of the readers of this little book will have seen what is known in _domestic parlance_ as a clothes-wringer. Here the wooden or rubber rollers, by means of weights or screws, are made to squeeze out most of the moisture which remains after the garment has left the washing-tub. Now if two sets of such rollers could be put together, so that in section the four centres would coincide with the four angular points of a square, and the back pair could be made to have a greater surface velocity than the front pair, this arrangement would give something like the idea which Paul had in his mind at that time. Why make the back pair revolve at a greater rate? For this reason, that as the cotton was supplied to the front pair, and passed on to the second, remembering that these are going at a greater rate, it follows that the cotton _would be drawn out_ in passing from the first to the second pair. Had the rollers been both going at the same speeds, the cotton would pass out as it went in, unaffected. Now it was this idea which Paul practically set out in his machine. From some reason or other, Paul's right to this patent has been often called into question, and up to 1858 it was popularly supposed to have been the sole invention of John Wyatt of Birmingham. In the year named, Mr. Cole, in a paper read before the British Association, proved that Paul was the real patentee, and established the validity of his claim without doubt.
The two distinguishing features of Paul's Spinning Machine were: (1) by means of the rollers and flyers he performed the operations of drawing-out and twisting, which had hitherto been done by the fingers and thumbs of the spinners; and (2) he changed the position of the spindle itself from the horizontal to the vertical.
A glance at the Transactions of the Society for the Encouragement of Arts, Manufactures and Commerce, shows that this period (1760-1770) was most prolific of inventions specially relating to the various sections of the cotton industry. There were "improved spinning wheels," "a horizontal spinning wheel," and three other forms of "spinning machines" submitted to the above society between 1761 and 1767, in the hope of obtaining money grants in the shape of premiums, which had been offered to the best inventions for improving spinning machinery in general.