60 deg. C., and then for twenty minutes in clear water
at 60 deg. C.

After wetting or preparatory treatment, it will be best to proceed
immediately to dyeing; if the fibres be left in a heap for too long a
time, there is danger that they may become heated, or at least that
the moisture may be irregularly distributed by the occurrence of
partial drying, causing an uneven fixation of the colour in the first
stages of dyeing. The first two conditions of successful dyeing are,
therefore, a suitable wetting out and scouring. The dyer, however,
must not be less careful to see that the dye-bath is what it ought to
be.

Whenever possible the dye-stuff must be dissolved separately, or at
least the bath not entered before the dye-stuff is well dissolved.
Artificial dye-stuffs require particular attention to this point,
because the presence of undissolved particles is the cause of (p. 080)
irregularities, such as streaks, or, at least, specks. The solution is
mostly made hot as follows: After pouring water at 180 deg. F. upon the
dye-stuff, stir gently, strain through flannel or through a very fine
sieve, and pour more water upon the residue until nothing more is
dissolved. As is well known, the artificial dye-stuffs often contain
insoluble matter, resins, etc. It is therefore advisable to use only
soft water for this operation.

The solutions of artificial dye-stuffs are ordinarily made at the rate
of 1 to 5 lb. per 10 gallons of water, 2 lb. being the proportion
mostly employed. This depends more or less on the solubility of the
dye-stuff. Old solutions sometimes contain crystals of the dye-stuff
which have separated out. These should be redissolved by heating
before the solution is used. But it is best to make only such a
quantity of solution as will suffice for immediate requirements.

With paste colours care should be taken to keep them in closed vessels
in such a manner that they will not become hard by evaporation, and
they should not be kept in any place where they are likely to freeze
in winter time. In such an event it is not an uncommon circumstance
for the casks or other vessels containing them to burst, with a
consequent loss of dye-stuff. Before any of the paste is withdrawn
from the cask, it is advisable to stir well up with a wooden stirrer.

In adding dye-stuff during the actual dyeing operation, it is
advisable to add the dye-stuff to the bath in two or three portions,
always taking out the goods bef