ed at which they are driven
leaves such a strain on the bearings as to seriously endanger the
safety of the machine.

[Illustration: Fig. 31.--Yarn-drying Machine.]

After being wrung, squeezed or hydro-extracted the goods are ready to
be dried. In the case of yarns this may be done in rooms heated by
steam pipes placed on the floor, the hanks being hung on rods
suspended from racks arranged for the purpose.

[Illustration: Fig. 32.--Cloth-drying Machine.]

Where large quantities of yarn have to be dried it is most economical
to employ a yarn or drying machine, and one form of such is shown in
figure 31. The appearance of the machine is that of one long room from
the outside, internally it is divided into compartments, each of which
is heated up by suitably arranged steam pipes, but the degree of
heating in each compartment varies, at the entrance end it is (p. 209)
high, at the exit end low. The yarn is fed in at one end, being
hung on rods, and by suitable gearing it is carried directly through
the various chambers or sections, and in its passage the heat to which
it is subject drives off the water it contains. The yarn requires no
attention from the time it passes in wet at the one end of the (p. 210)
machine and comes out dry at the other end. The amount of labour
required is slight, only that represented by filling the sticks with
wet yarn and emptying the dried yarn. The machine works regularly and
well.

The drying is accomplished by circulating heated air through the
yarns, this heating being effected by steam coils; fresh air
continually enters the chambers while water-saturated air is as
continually being taken out at the top of the chamber. One of the
great secrets in all drying operations is to have a constant current
of fresh hot air playing on the goods to be dried, this absorbs the
moisture they contain, and the water-charged air thus produced must be
taken away as quickly as possible.

#Piece Goods.#--The most convenient manner of drying piece goods is to
employ the steam cylinder drying machine such as is shown in figure
32. This consists of a number of hollow tin or copper cylinders which
can be heated by steam passing in through the axles of the cylinders,
which are made hollow on purpose. The cloth to be dried passes round
these cylinders, which revolve while the cloth passes. They work very
effectually.

CHAPTER VIII. (p. 2