11. Topical Prussian blue for grounding.
2 quarts of water with 8 ounces of starch, are to be mixed and boiled; add 21⁄4 ounces of a liquid Prussian blue colour, prepared by triturating three quarters of an ounce of that pigment with as much muriatic acid, leaving the ingredients to react upon each other for 24 hours, and then adding three quarters of an ounce of water.
Add 4 ounces of liquid perchloride of tin (oxymuriate).
Mix all together, and pass through a searce. This colour is not very fast; cloth printed with it will bear only rinsing.
12. Prussian blue figures are impressed as follows:—
Dissolve 8 ounces of sulphate of iron, and as much acetate of lead, separately in 2 quarts of boiling water; mix well, and settle. Take one quart of this clear liquor reduced to spec. grav. 1·02, one quart of mucilage containing 3 pounds of gum, coloured with a little prussiate of potash, mix into a mordant, and print it on with the cylinder. Two days afterwards wash in tepid water containing a little chalk, and then pass the cloth through a solution of prussiate of potash in water, sharpened with a little muriatic acid, till it takes the desired hue. Finally rinse.
II. The padding or plaquage style, called foulard also by the French. See [Padding].
Any mordant whatever, such as the acetates of alumina, or of iron, or their mixture, may be applied to the piece by the padding machine, after which it is dried in the HOT-FLUE, washed, dunged, dyed, washed, and brightened.
Colours from metallic oxides are very elegantly applied by the padding process. Thus the iron buff, the manganese bronze, and the chrome yellows and greens are given.