I. For this delicate color, as well as for the lightest shades of
blue and pure yellow, absolutely white feathers must be used; scour
them carefully and rinse them perfectly clean from soap or soda, and
have the dyestuffs well dissolved and the solutions filtered. Prepare
a handwarm bath with a little tartaric acid or acetic acid, to which
some solution of eosine, rhodamine, azoeosine, safranine, coccine or
ponceau 6 R. B. or ponceau R. R. Be particularly cautious in adding the
dyestuff solutions gradually in small quantities, even by drops, to
avoid over-dyeing, as by partly stripping of a too dark shade, a fine
color can never be obtained, and the nature of the material demands
that all unnecessary handling be avoided. After dyeing, rinse lightly,
pass through starch and dry. The dyes with the ponceaus are faster than
those with eosine or safranine.
II. Prepare a bath at hand heat with carthamine (extract of safflower),
well dissolved and filtered, which add very gradually in small
quantities, taking up the feathers each time before making a fresh
addition, until the desired shade is nearly obtained, then add a little
tartaric acid to the bath, re-enter the feathers and dye to shade; or
dye first to shade upon the safflower bath, and then pass through a
fresh, handwarm feeble bath of tartaric acid, which in this case can
be used again for other colors, either as a fixing bath or in the
composition of the dye bath.