Stable And Changeable Colors. - Frauds.

Scientific American 8, 24.8.1861

A paper was lately read before the Paris Academy of Sciences, by M. Chevreul, in which he directed at­tention to the importance of classifying colors on goods and giving them correct names, so as to afford more security to merchants and the public without interfering with the freedom of business. Instead of the vague and useless names of colors now applied to goods, he proposes that their qualities of endurance shall be as follows :—Very stable, stable, moderately stable, changeable, expressed in degrees according to the time which these colors will endure when exposed to light and air. Indigo and madder are about the only substances known which produce very stable colors with certain mordants. Cochineal and weld produce stable colors, Brazil and Campeachy woods are moderely stable; annotto, turmeric and safflour pro­duce fugitive colors.

M. Chevreul regrets that the new muroxyd and ani­line colors should have been so much over-praised. They are beautiful and agreeable to the eye when fresh, but they soon fade when exposed to the sun. The old stable colors obtained from indigo, madder, cochineal and weld, will remain in favor and be ap­plied in manufactories, when their new rivals will have disappeared. Great deceptions are frequently practiced in the coloring of cloth.

A regiment belonging to this city lately returned after three months' service, and the blue coats of all the companies but one, seemed to be about as bright as they were on the day the men left. The excep­tional Company had not been in service over eighteen weeks, as it was a reserve raised aftee the body of the regiment had gone to Washington; and all the coats of this company were entirely new when the men went away, and they were of a deep rich blue color, but they had become a dirty drab color on the shoulder and all the parts that had been most exposed to sun light. This cloth had been colored with logwood instead of indigo, and it runs a fraud, as logwood can be applied for one-fourth the cost of indigo at the very most. Shell frauds should be traced to their source and the guilty parties made disgorge.

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