All light colored feathers can be used for navy blue without first
either washing or bleaching out any of the color. But if your feathers
be very dirty or greasy, especially the latter, wash them well in warm
soap water and rinse. Prepare bath by diluting about one teaspoonful
of concentrated cotton blue in one gallon of boiling water; add about
a teaspoonful of oxalic acid. Stir around well to thoroughly dissolve
aniline; then enter your feathers, and raise temperature of your bath
to boiling. Let feathers remain in about three minutes; a minute more
will not do any harm, only have a tendency to make your color a little
richer; after which take feathers out of bath and rinse thoroughly in
cold water for the purpose of removing all loose particles of color
and the acid; having boiling meantime a bath of logwood of medium
strength; enter feathers, letting them remain therein about one-half a
minute; take out and rinse in cold water; dilute about half an ounce
of bichromate of potash in a gallon of boiling water; enter feathers,
let them remain in about half a minute, and stir them around well in
bath; after which take them out and rinse in cold water and starch and
dry. Should you desire a darker shade, rinse off starch, and return
to logwood bath for a few seconds, rinse off and repeat bichromate of
potash bath; then rinse, starch and dry. In this way, by repeating the
logwood and bichromate of potash, you can darken your color down almost
to a black.
Should you get your color darker than your sample to be matched, rinse
off starch in clear cold water, and dilute a teaspoonful of oxalic acid
in a gallon of hot water almost boiling and enter feathers, passing
them through about a half minute; after which take out and pass through
a basin of boiling water a few seconds. This will draw off the surplus
of logwood and chrome, and then mix a starch bath luke warm; add
thereto a half teaspoonful of oxalic acid for the purpose of bringing
up the blue. This process will reduce your color three or four shades;
then pass feathers and dry. This process of dyeing navy blue produces
a rich, even shade that is perfectly fast to light and alkali, and with
the smallest degree of judgment by the dyer it is impossible to have a
failure.