resting on the edges of the
tub or vat. These sticks are best made of hickory, but ash or beech or
any hard wood that can be worked smooth and which does not swell much
when treated with water may be used. The usual method of working is to
hang the skein on the stick, spreading it out as much as possible, then
immerse the yarn in the liquor, lift it up and down two or three times
to fully wet out the yarn, then turn the yarn over on the stick and
repeat the dipping processes, then allow to steep in the dye-liquor.
This is done with the batch of yarn that is to be dyed at a time. When
all the yarn has been entered into the dye-bath, the first stickful is
lifted out, the yarn turned over and re-entered in the dye-liquor, this
operation is carried out with all the sticks of yarn until the cotton
has become dyed of the required depth. In the case of long rectangular
vats it is customary for two men, one on each side of the vat to turn
the yarns, each man taking charge of the yarn which is nearest to him.
The turning over one lot of yarn is technically called "one turn" and
the dyer often gives "three turns" or "four turns" as may be required.
Woven goods may be dyed in the tub or vat, the pieces being drawn in and
out by poles, but the results are not altogether satisfactory and it is
preferable to use machines for dyeing piece goods.
[Illustration: FIG. 8.--Section of Dye-vat.]
Plain tubs or vats, such as those shown in Figs. 6 and 7, are used for
dyeing, and otherwise treating goods in the cold, or at a lukewarm heat,
when the supply of hot water can be drawn from a separate boiler. When,
however, it is necessary to work at the boil, then the vat must be
fitted with a steam coil. This is best laid along the bottom in a
serpentine form. Above the pipe should be an open lattice-work bottom,
which, while it permits the free circulation of boiling water in the
vat, prevents the material being dyed from coming in contact with the
steam pipe. This is important if uniform shades are to be dyed, for any
excessive heating of any portion of the bath leads to stains being
produced on the material in that part of the bath. Fig. 8 shows a vat
fitted with a steam pipe. That portion of the steam pipe which passes
down at the end of the vat is in a small compartment boxed off from the
main body of the vat, so that no part of the material which is being
dyed can come in contact with it. A closed steam coil will, on the
whole, give th
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