fferent liquids or
all the same liquid according as the nature of the shade to be dyed
demands. The passage is done slowly so as to give the warp time to
absorb the liquors and take up the dye. When all the length of warp has
been sent through, it is said to have been dyed "one end". Sometimes
this will be enough, but often it is not, and so the warp is sent
through again, given another end, and still again if the full shade has
not been attained.

After being dyed in this machine the warp is sent through another one
containing various wash liquors to finish the process.

[Illustration: FIG. 17.--Warp-dyeing Machine.]

Fig. 17 shows a warp-dyeing machine similar to, but a little more
elaborate in construction than, the vats just described.

=Piece-dyeing Machines.=--Wherever it is possible it is far more
preferable to dye textile fabrics in the form of woven pieces rather
than in the yarn from which they are woven. During the process of
weaving it is quite impossible to avoid the material getting dirty and
somewhat greasy, and the operations of scouring necessary to remove this
dirt and grease has an impairing action on the colour if dyed yarns
have been used in weaving it. This is avoided when the pieces are woven
first and dyed afterwards, and this can always be done when the cloths
are dyed in one colour only. Of course when the goods are fancy goods
containing several colours they have to be woven from dyed yarns.

[Illustration: FIG. 18.--Dye-jiggers.]

[Illustration: FIG. 19.--Dye-jigger.]

The most common form of machine in which pieces are dyed is The Jigger,
commonly called the jig. This is shown in Figs. 18 and 19. It consists
of a dye-vessel made sufficiently long to take the piece full
width--wide at the top and narrow at the bottom. At the top at each side
is placed a large winding roller on which the cloth is wound. At the
bottom of the jig is placed a guide roller round which passes the cloth.
In some makes of jigs (Fig. 19) there are two guide rollers at the
bottom and one at the top, as shown in the illustration, so that the
cloth passes several times through the dye-liquor. In working, the cloth
is first wound on one of the rollers, then threaded through the guide
rollers and attached to the other winding roller. When this is done
dye-liquor is run into the jig, the gearing set in motion, and the cloth
wound from the full on to the empty roller. With the object of keeping
the piece tight, a hea