DYEING AND CALICO PRINTING .

380

80 grms.; albumen water, 1 litre; if a bluish hue is desired some neutralindigo extract should be added. The materials are printed, dyed, steamed, andnext washed in boiling water.

Cotton as prepared for Turkey-red dyeing (oiled cotton), or also cotton pre-viously albuminised, take up this colouring matter when placed in a bath con-taining the purple (previously decomposed with its weight of oxalic acid,filtered, to eliminate the oxalate of lime, and next dissolved by the aid ofsome ammonia); the temperature should be raised to 6o°. Non-mordantedwool placed in a boiling hot bath of the ordinary orchil of commerce assumesa beautiful and pure red, violet-red, or violet, according to the quality of theproduct used. French purple decomposed, or rather deprived of its lime andset free by means of oxalic acid and neutralised with ammonia, yields, uponwool, a very beautiful and fast violet-purple. For the so-called bright groseille-red and deep violet-groseille, wool, previously mordanted with tin, is dyedwith orchil only, 10 kilos, of wool, 1 kilo, of cream of tartar, 2 litres of tinsolution (made up of 400 grms. of common salt, 1*25 kilos, of tin, and 8 litresof nitric acid) ; the wool is kept for an hour in this mixture at boiling heat.For medium groseille-red ammoniacal cochineal and orchil are used together.Orchil is also used along with other dye-wares to obtain the followingcolours :—

Amaranth Red.—Mordant for red. Crude cochineal and orchil.

Amaranth Bright.—For medium and deeper hues the quantity of orchiltaken is increased, and as regards the very deep hues sulphate of indigo alsois added.

Amaranth Violet.—As for preceding.

Feuille Morte.*—The mordanting is done with alum and sulphuric acicl(10 kilos, of wool, 2 kilos, of alum, 20 grms. of sulphuric acid, boiled togetherwith water for an hour); the dye material consists of a mixture of orchil,neutral extradt of indigo, and turmeric.

Wood Colour (£0/5).—Mordanting with cream of tartar and tin solution,dyeing with orchil, neutral extradt of indigo, turmeric, and fustic liquor.

The shades known as pommerolle and carmelite are produced by the samemordants and dye-wares, the only difference being the quantities applied.Very large quantities of orchil are consumed in printing woollen fabrics(steam colours). As examples of the shades and of the mode of preparationthe following may serve:—Reddish brown (puce) orchil liquor, 2 litres;sulphate of alumina, 120 grms.; Senegal gum, 200 grms. Brown (puce)orchil liquor, 2 kilos.; sulphate of alumina, 120 grms.; Senegal gum, 200 grms.;indigo carmine, 60 grms. After printing and dyeing the goods are steamedand next washed. In'order to apply French purple as steam colour uponwool and silk the dye material is dissolved in acetic acid, neutralised withcarbonate of magnesia ; alcohol is added, and gum water as thickener; theseare applied by cylinder, and the fabric afterwards steamed.

Orchil dyes silk diredtly without the use of any mordant, the shades beingsimilar to those produced on wool. The French purple yields on silk abeautiful mauve or dahlia colour when used alone. If mixed with indigo ex-tract it yields a very good violet; with cochineal, peach-blossom, groseille,

* A peculiar hue which the leaves of many trees and shrubs assume in the autumn justprevious to falling.