they contain, and the water-charged air thus produced must be taken away as quickly as possible.
FIG 43.—Drying Cylinders.
Fig. 42 shows what is called a truck yarn-dryer, which consists of a chamber heated with steam pipes and fitted with an exhausting fan to draw out the air and water vapour which is produced. The yarns are hung on trucks
which can be run in and out of the chamber for filling and emptying.
Piece Goods.—The most convenient manner of drying piece goods is to employ the steam cylinder drying machine, such as is shown in Fig. 43. 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. The cylinders are arranged sometimes, as in the drawing, vertically; at other times horizontally.
CHAPTER VIII
TESTING OF THE COLOUR OF DYED FABRICS.