t the speed of the rove passing on to the
various diameters must be maintained throughout, and must coincide
with the delivery of yarn from the rollers, so that the attenuated
but slightly twisted sliver can be wound on to the bobbin without
strain or stretch. The varying motion is regulated and obtained by a
drive, either from friction plates or from cones, and the whole gear
is interesting, instructive--and sometimes bewildering--two distinct
motions, a constant one and a variable one, are conveyed to the
bobbins from the driving shaft of the machine.

The machine illustrated in Fig. 18 is of special design, and the
whole train of gear, with the exception of a small train of wheels
to the retaining roller, is placed at the pulley end--that nearest
the observer. The gear wheels are, as shown, efficiently guarded,
and provision is made to start or stop the machine from any position
on both sides. The machine is adapted for building 10 in. X 5 in.
bobbins, i.e. 10 in. between the flanges and 5 in. outside diameter,
and provided with either 56 or 64 spindles, the illustration showing
part of a machine and approximately 48 spindles.

The machines for rove (roving frames) are designated by the size of
the bobbin upon which the rove is wound, e.g. 10 in. x 5 in. frame,
and so on; this means that the flanges of the bobbin are 10 in.
apart and 5 in. in diameter, and hence the traverse of the builder
would be 10 in. The 10 in. x 5 in. bobbin is the standard size for
the ordinary run of yarns, but 9 in. x 4-1/2 in. bobbins are
used for the roves from which finer yarns are spun. When the
finished yarn appears in the form of rove (often termed spinning
direct), as is the case for heavier sizes or thick yarns, 8 in. x 4
in. bobbins are largely used.

Provision is made on each roving frame for changing the size of rove
so as to accommodate it for the subsequent process of spinning and
according to the count of the required yarn; the parts involved in
these changes are those which affect the draft gearing, the twist
gearing, and the builder gearing in conjunction with the automatic
index wheel which acts on the whole of the regulating motion.

CHAPTER X. SPINNING

The final machine used in the conversion of rove to the size of yarn
required is termed the spinning frame. The actual process of
spinning is performed in this machine, and, although the whole
routine of the conversion of fibre into yarn often goes under the
n