the yarn throughout
the process. An automatic stop motion is provided for each bobbin;
this apparatus lifts the bobbin clear of the discs when the bobbin
is filled as exemplified in the illustration.

The distance between the flanges of the bobbin is, obviously, a
fixed one in any one machine, and the diameter over the yarn is
limited. On the other hand, rolls may be made of varying widths and
any suitable diameter. And while a bobbin holds about 2 lb. of yarn,
a common size of roll weighs, as already stated, from 7 to 8 lb.
Such a roll measures, about 9 in. long and 8 in. diameter; hence for
8 lb. yarn, the roll capacity is 14,400 yards.

Rolls very much larger than the above are made on special machines
adopted to wind about six rolls as shown in Fig. 23. It is built
specially for winding heavy or thick yarns into rolls of 15 in.
diameter and 14 in. length, and this particular machine is used
mostly by rope makers and carpet manufacturers. One roll only is
shown in the illustration, and it is winding the material from a 10
in. x 5 in. rove bobbin. The rove is drawn forward by surface or
frictional contact between the roll itself and a rapidly rotating
drum. The yarn guide is moved rapidly from side to side by means of
the grooved cam on the left, the upright lever fulcrumed near the
floor, and the horizontal rod which passes in front of the rolls and
upon which are fixed the actual yarn guides. This rapid traverse,
combined with the rotation of the rolls, enables the yarn to be
securely built upon a paper or wooden tube; no flanges are required,
and hence the initial cost as well as the upkeep of the foundations
for rolls is much below that for bobbins.

[Illustration: _By permission of Messrs. Charles Parker, Sons & Co_.
FIG. 22 BOBBIN WINDING MACHINE WITH HANKS]

Precisely the same principles are adopted for winding the ordinary 9
in. x 8 in. or 8 in. x 7 in. rolls for the warping and dressing
departments. These rolls are made direct from the yarn on spinning
bobbins, but the machines are usually double-sided, each side having
two tiers; a common number of spools for one machine is 80.

The double tier on each side is practicable because of the small
space required for the spinning bobbins. When, however, rolls are
wound from hank, as is illustrated in Fig. 24, and as practised in
several foreign countries even for grey yarn, one row only at each
side is possible. Both types are made by each machine maker, th