Manufacture of Colors.

Scientific American 7, 16.2.1861

A late English traveler among the tribes of wandering Turkomans on the plains of Tarsus and the mountains of Syria, states that the art of dyeing brilliant colors is held in very high estimation among the females of the tribes. Every marriagealde girl must have first worked a carpet of more than ordinary beauty, colored with the choicest dyes, as a treasure for her marriage festival. From time immemorial, the art of coloring textile fabrics has been greatly prized. In all manufacturing nations much attention is paid to "color chemistry," because superiority in this particular department is of the greatest consequence to mercantile success. France is distinguished for her silk, woolen and fine cotton fabrics, and the unrivaled skill of her color chemists; and the government of that empire generally selects the first chemist in the country to preside ocer the royal tapestry manufactory in Paris.

Vegetable substances have been, and are still, the most common coloring agents, but chemists have more recently devoted much attention to synthetical chemistry relating to the manufacture of mineral coloring compounds. When it is considered that almost every article of clothing, and most of the textile fabrics, such as carpets and curtains, that are employed in house furnishing, is colored, the amound of chemicals employed in the arts for this purpose must be prodigious. And when we also consider that some of these chemicals, such as cochineal and indigo are very costly, being from one to two dollars per pound, we can form some idea of the great annual expense incurred for them, especially when, for only three imported dye stuffs, viz, madder, indigo and cochineal, we pay about three millions of dollars per annum. Another reason why chemists have of late years devoted much attention to mineral colors, is the fluctuating supply of vegetable dyes, the most expensive of which are derived from annual crops. If we could obtain all our coloring substances from the same source as that from which we derive our iron, coal and marble, the supply would be constant, and the quantity limited only by the demand. Considerable success has already attended the efforts of chemists in their experiments to obtain mineral colors for textile fabrics, and yet the field for experiment has been merely scratched; it is still very inviting for thorough cultivation.

The bichromate of potash is a pure mineral substance for coloring yellow, and it has almost superseded quercitron part and fustic; the arsenite of copper is also purely mineral dye, but it should be prohibited because its poisonous qualities; but above all these, the most curious and brilliant colors ever obtained, are the new aniline dyes, which are manufactured from that Hottentot perfume and refuse of gasworks, coal ttar. With the exception of samples of aniline colors, made to order by Charles Scely, chemist, this city, we believe, that all out dyers have hitherto imported their dyes from London, at a cost of more than sixteen dollars per gallon. It is our opinion that every color now produced on textile fabrics, with vegetable and animal substances, may be imitated and profitably superseded with mineral substances. When this is accomplished, a complete revolution will be effected in "color chemistry."

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