The following list of dyes, and the co loring substances which produce them, may prove useful.
Red. Cochineal, kermes, lac, madder, archil, carthamus or safflower, Brazil wood, logwood, periodido of mercury, alkanet.
Yellow. Quercitron, weld, fustic, (yel low wood) annotto, sawwort, dyer's broom, turmeric, fustic, (rhos cottnus) Persian and Avignon berries, (rhanznus willow, peroxide of iron ; chromate of lead, (chrome yellow) sul phnret of arsenic, hydrosulphuret of an timony; nitric acid on silk.
Blue. Indigo, woad or pastel, Prus sian blue, turnsole or litmus, logwood with a salt of copper.
Black. Galls, sumach, logwood, wal nut peels, and other vegetables which contain tannin and gale acid, along with ferruginous mordants. The anacardi um of India.
Green. These aro produced by the blue and yellow dyes skillfully combined; with the exception of the chrome green, and perhaps the copper green of Schwein furt.
Orange. Annotto, and mixtures of red and yellow dyes ; subchromate of lead.
Dun, Boot. Walnut peels, su mach, birch-tree, henna, sandal wood.
The chemical principles of the art of calico printing are the same as those of dyeing, but the details are more difficult and complicated ; and in consequence of the combination of a great variety of co lors upon the same ground, the process is sometimes extremely refined and intri cate ; so that a rich, varied, and pleasing pattern, thus effectively produced, may be considered as a triumph of practical skill over theoretical difficulties, which is scarcely rivalled, and certainly not ex celled, in any other of the arts. It is ob vious that calico printing is in the abstract a topical dyeing ; and much discrimina tion and taste are requisite in the con trivance of the pattern, its general de sign, and the colors in which it is exhib ited. In this art the mordantt, and
sometimes the colors, arc applied either by blocks, upon which the pattern is de signed in relief, or by copperplates, which are engraved, or by cylinders or rollers. If the aluminous mordant be printed by one block and the iron mordant by ano ther, and the mixture of the two by a third, and the piece thusprepared be then passed through a madder bath, and properly cleansed and bleached, the color will only adhere to the mordanted places, and it will be red where the aluminous earth only has been applied, purple with the mixed mordant, and black with the iron ; if the same three mordants be used with a decoction of quercitron bark, the resulting colors will be yellow, olive, and brown ; and in this way a great variety of colors may be produced. Sometimes copperplate and block printing are com bined ; a fine running pattern being printed by the plate or cylinder over the whole surface, which serves as a ground work, and upon which other figures are printed by blocks. Sometimes the mor dant and color are both applied at once by means of a block, and rendered fixed and permanent by exposing the goods for some time to steam. Beautiful effects are produced by printing the patterns on a mordanted ground with some substance which will resist the color, and so pro duce a white pattern on a colored ground. (See CALICO PRINTING.)