II.—Blue Dye.—Take a sufficient quantity of potash lye, 1 pound of litmus or lacmus, ground; make a decoction and then put in the straw, and boil it.
To Dye, Stiffen, and Bleach Felt Hats.
Felt hats are dyed by repeated immersion, drawing and dipping in a hot watery solution of logwood, 38 parts; green vitriol, 3 parts; verdigris, 2 parts; repeat the immersions and drawing with exposure to the air 13 or 14 times, or until the color suits, each step in the process lasting from 10 to 15 minutes. Aniline colors may be advantageously used instead of the above. For a stiffening, dissolve borax, 10 parts; carbonate of potash, 3 parts, in hot water; then add shellac, 50 parts, and boil until all is dissolved; apply with a sponge or a brush, or by immersing the hat when it is cold, and dip at once in very dilute sulphuric or acetic acid to neutralize the alkali and fix the shellac. Felt hats can be bleached by the use of sulphuric acid gas.
Liquid Dye Colors.
These colors, thickened with a little gum, may be used as inks in writing, or as colors to tint maps, foils, artificial flowers, etc., or to paint on velvet:
I.—Blue.—Dilute Saxon blue or sulphate of indigo with water. If required for delicate work, neutralize with chalk.
II.—Purple.—Add a little alum to a strained decoction of logwood.
III.—Green.—Dissolve sap green in water and add a little alum.
IV.—Yellow.—Dissolve annatto in a weak lye of subcarbonate of soda or potash.
V.—Golden Color.—Steep French berries in hot water, strain, and add a little gum and alum.