ture at which the
dyeing is carried on, the character and condition of the fabrics being
dyed, etc.

The volume of water used in making the dye-bath has a very great
influence upon the amount of dye taken up by the cotton, the greater the
volume of water the less dye is absorbed and the paler the colour which
is produced upon the fibre. It is therefore important to use as little
water as possible in making up the dye-bath, indeed, for anything like
good results to be obtained with some dyes, especially those of the
sulphur series like Vidal black, Immedial blacks, Katigen browns,
Cross-dye blacks, Amidazol blacks, etc., it is necessary to employ what
is called a short bath, that is making it as strong as possible. The
proportion of water with such dyes should not exceed fifteen times the
weight of the cotton being dyed, that is, for every pound of cotton,
1-1/2 gallons of water can be allowed. This will suit the dyeing of
yarns and loose fabrics like knitted stockings and hosiery goods very
well. In the case of dyeing piece goods on a jigger or continuous dyeing
machines even stronger liquors can be used with advantage. With some of
the older, direct dyes like Congo red, Benzo azurine, Diamine scarlets,
the proportion of water may be increased to twenty times the weight of
the cotton. In any case the quantity of water used should not exceed
twenty-five times the weight of the cotton.

The second factor, the quantity of saline salts, like Glauber's salt,
soda, borax, etc., added in the dyeing, is not without influence,
generally the more that is added the more dye there is left in the bath,
but here again much depends upon the salt and the colouring matters
used. Some salts, more particularly Glauber's salt and common salt, tend
to throw some dye-stuffs out of the bath, and so the more there is used
of them the deeper the shade produced on the fabric. It is quite
impossible, having regard to the scope of this book, to deal with this
question in detail. The dyer should ascertain for himself the best salts
and the best proportions of these to use with the particular dyes he is
using. The recipes given above will give him some ideas on this point.

The third factor, the degree of affinity of the dye for the cotton
fibre, has some influence on the depth of shade which can be dyed from
any given strength of the dye-bath. There is a very considerable
difference among the direct dyes in this respect. There are some which
hav