There can be no doubt that one of Arkwright's
greatest difficulties was to give an uniform yarn, and though he
successfully launched his new machines he felt there was still much to
be done in the direction of remedying yarn which was irregular in
thickness and strength. In order to do this, he finally adapted his
drawing rollers to what is now the modern drawing frame--a machine quite
as largely used, and quite as necessary in present-day spinning, as it
was a hundred years ago.

It was sought to make this machine do two things. (1) Several slivers
of cotton from the Card were put up together at the back, and by means
of four pairs of drawing rollers, were reduced to the thickness of one
sliver (see the description in chapter vi.). It will be sufficient to
say here that this method of doubling and drawing equalises the sliver
of cotton by the combination of the thick places with the thin.

Doubling is now the reason of the uniformity of the yarns that are
produced in such large quantities.

(2) The Carding Engine did not by any means lay the fibres of cotton
sufficiently parallel to each other, and this process of parallelisation
was fully accomplished by the front ends of the fibres being drawn
forward more rapidly than their back ends by the drawing rollers
revolving at different velocities. Mr. Baines says it was common to
perform this operation until the finished sliver contained portions from
_several thousand_ carding slivers, but we think he would have been
nearer the mark if he had said several hundred; although the higher
number may be occasionally reached.

Yet again, in order to obtain a thread or yarn of sufficient fineness,
it was found necessary to perform some of the attenuation of the
cotton sliver as it left the drawing frame and before it reached the
final spinning process. To this end, Arkwright adopted the Roving frame,
in which the leading feature was again the celebrated drawing rollers.
This machine made a soft and moderately twisted strand or roving, and if
much twist had been put in, it would have refused to draw out finer at
the spinning machine. Hence the means provided by Arkwright for the
twisting and winding-on of the attenuated cotton on his spinning frame
were utterly inadequate to cope with the soft loose roving, and as a
matter of fact Arkwright never did see this problem satisfactorily
solved.

He allowed, in his machine, the roving to fall into a rapidly revolving
can which st