Feathers for lavender must be white, or nearly so, if you desire a
good clear shade. All light colors can be used by first bleaching with
permanganate of potash, or if only dirty white feathers, wash and rinse
them thoroughly. Prepare bath of luke warm water and a small handful
of starch, rub feathers around between the hands to expand the fibres;
then add to bath a few drops of diluted violet. Enter your feathers
and let remain about one minute in bath, keeping them meanwhile in
motion; take out your feathers and add to bath a drop of diluted
safranine; re-enter and raise temperature of bath a few degrees by
addition of hot water; let your feathers remain about half a minute
in bath; if wanted darker, add a few drops of diluted violet, and if
lighter, less; after which take out your feathers and dry them in the
usual way, being careful to use clean starch for drying. To use starch
that had previously been used to dry light colors that contained acid,
would most likely result in spotting your color, as the application
of acid to any portion of the delicate color would turn it a greenish
blue. If your color be found too dark for sample, you can either wash
in a solution of soap water, or else pass feathers through a bath of a
teaspoonful of oxalic acid to a gallon of luke warm water, after which
rinse off well and put through fresh bath as per recipe.