Scientific American 19, 20.1.1855
Red on Wool.
In ancient times Tyre was famous for dyeing purple on fine wool. So expensive was this color that it was worn only by kings. The accounts of it are somewhat fabulous; Pliny describes it as obtained from a certain species of shell-fish named "Murex." In the reign of Augustus, one pound of fine wool dyed of the richest bloodred hue was valued at about $160. This method of dyeing red on wool is now unknown.
Next to the Tyrian purple was the "Kermes Red," so called from the insect with which it was dyed. It was known to the Greeks and Romans. It was found on a small species of oak growing in most of the southern parts of Europe. The wool for this dye being well cleared was prepared by boiling one hour in a solution of alum and coarse tartar — the quantity of alum was one-fifth that of the wool, and the tartar one-half that of the alum. It was allowed to steep in thin liquor for three days, then taken out, washed, dripped, and dyed by boiling it for one hour in a bath of ground kermes, of twelve ounces to the pound of wool. It was then washed and dried. Kermes red was very permanent, but now unknown in the arts; cochineal and lac have entirely superseded it.
Cochineal.
The most beautiful of all red colors is that produced by cochineal — the cactus cacti of Mexico. These insects feed on the cactus plant, and are cultivated by the natives of Honduras - where the finest grow - simply as a dye drug. They are swept off with feathers into pans of hot water, and afterwards dried for market. The wool for red being well scoured and washed is introduced into a bath of ground cochineal, and its mordant, and finished at one operation. The wool must be white, the dye kettle must be very clean, and either of copper or tin. To dye five pounds of wool, let seven and half ounces (1½ to the pound) of ground cochineal be introduced into the kettle, and boiled for five minutes; then introduce ten ounces of cream of tartar and a large wine-glass full of the nitro-muriate of tin; stir all up, and introduce the wool, handling it neatly and rapidly. Allow it to boil for three quartets of an hour, and a good full color may be expected. This is the most beautiful red dye in the world, and the most easy and simple to dye. It is dearer, however, than the Lac. This is the product of an insect, a native of the Wast Indies. There are different kinds of it, that used for dyeing is prepared for this purpose. About four ounces of lac (some kinds require six) are employed to dye one pound of wool. It is prepared for dyeing by steeping it (the lac) for twenty-four hours in strong hydrochloric acid, stirring it from time to time, and then dyeing in a bath the same as cochineal. It is a cheaper and more common but much inferior color to cochineal. All goods that are dyed with spirits of any kind, or acids, must be well washed before they are dried.
Scarlet.
A little yellow oak bark liquor added to the cochineal or the lac bath, makes the color scarlet, instead of a red; that is, it turns a binary color composeed of the red and yellow rays - the red predominating.
The proportions of dye stuffs given will answer for yarn; cloth requires less, but there is also a great difference in the quality of the wool. The coarser the woo1, the more dye stuffs are required, and vice versa. One ounce of the best cochineal will dye very good color on a pound of fine merino wool.
Madder red.
This color has been long and pretty generally known among our country folks. To dye one pound of yarn or flannel, three ounces of alum and one of the cream of tartar, are the proportions for every pound. To dye five pounds of flannel take one pound of alum, and five ounces of cream of tartar, and after they sre dissolved in water in a clean brass or copper kettle, enter the flannel loosely, and keep poking it down under the liquor, and gently raising it from the bottom and boiling for about one hour and a half. Take it out, hang it up, and air it for fifteen minutes and then wash it well in cold water. The kettle being emptied and filled with clear water, into which two and a half pounds of good ground crop madder, (well broken and mixed in a little cold water previously) have been introduced. Warm up this to such a heat as the hand will bear, introduce the flannel, and bring it up to a scalding heat, taking about half an hour to do so, then keep it at this heat for another half hour, and boil for ten minute. It is then lifted and aired, and about a quart of clear lime water introduced and stirred in the liquor, when the flannel is again entered, and handled for ten minutes. It should then bo good rosy red. Care must be taken to get good madder.
A very excellent plan for bleeding the madder, as it is termed, is to steep the quantity intended to be used in dyeing, over night in clear decoction of bran — about two pounds of bran should be used for every one of madder, in about two gallons of water.
Nicaragua Red
— This is the most fugitive of reds on wool, because it will not stand washing so well as the others described; it is, however, easily dyed, and on fine wool in a very rich and pretty color. The wool is prepared in the same manner as for madder (flannel should never be dyed with this stuff,) and then in a clean liquor of boiled Nicaragua chips at the rate of half a pound to the pound of wool, which is introduced into a clean copper kettle, brought to a boil, the wool entered and handled well for three quarters of an hour, after which it may be taken out, washed and dripped, and is ready for drying. It Brazil wood is used, six ounces to the pound will answer. Both Brazil wood andd Nicaragua dye woods should be boiled up to a strong liquor, and kept standing in vat for use. It is a fact well known to dyers that such liquors make more beautiful colors than it used at once from boiled chips.
Nicaragua red can also be dyed at one operation like cochineal red, by using only about two ounces of alum to the pound of wool, but using more dyewood. Where time is of the most consequence, this plan thould be pursued.
All these red colors on woolen goods are easy to manage, if the goods be clean. The madder red is the most troublesome on account of the difficulty in detecting bad stuff. All deep dull reds on merino twilled cloth are dyed with Brasil wood; the bright reds of tartans (woolen checks) are generally dyed with lac; and the very brightest with cochineal. Madder is seldom used for dyeing red in the workshop, although it is the most permanent color.
The discovery of dyeing red and scarlet on wool and silk with cochineal, and base of tin dissolved in acid is attributed to a Dutch chemist — a Hollander — named Cornelius Drebel; this was in 1630. It was a grand discovery, for it is the most brilliant of all colors. It was termed "Dutch scarlet" for many years after his discovery. It is to be regretted that cochineal is so expensive, being about two dollars per pouud, but its cultivation is troublesome. We have been told that those peans in Mexico who gather it, are sad looking objects during such labor. Their faces and hands get scratched with the cactus, and then break out into fearful looking sores.
We will describe the methods of dyeing red on silk, in our next.
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