More about Cochineal to Dye Silk. Scarlet and Crimson.

Scientific American 4, 13.10.1849

For the Scientific American.
All silk which has its natural gum in it, must be boiled in strong soap to take away its gum, which it will do, showing that more substances than either turpentine or alcohol can dissolve it. Spun silk for dyeing has only to be well wet out in very hot water, it is then wrung up and scutched well out. For scarlet it is bottomed with a good full annato yellow, washed out of it, and wrung up for the spirits. The spirits or mordant for silk to be dyed red is the nitro-muriate of tin, yet for a sure and excellent spirits, the simple muriate of tin can answer every purpose.

Kurst, the German, who first brought the secret of using the nitro muriate of tin in dyeing with cochineal, to London, established, or laid the foundation in that city for making the best cochineal colors, at least on silk, in the world, a pre-eminence which she enjoys in some respects even at the present day.

The mordaunt is made up in a tub, a little warm, with about tjree oz. of white tartar to the pound, and spirits made up in the tub to stand two in the No. 1 hydrometar. The silk is agitated or well handled in this liquor, for about four hours, after which it is taken out and wrung or squeezed, to be entered in the cochineal. But previous to this, (getting the mordaunt,) the silk should have been dyed for scarlet a bright yellow with annato.

The tubs for dyeing silk in, are wide at the mouth and narrow at the bottom, being deep enough to work at without stooping. The best way to prepare the cochineal for dyeing silk, is to boil it for about fifteen minutes in bran water, and then put it in your tub which must be made up at a good heat and with soft water. Three oz. of cochineal boiled in bran water will make a good color, but four oz. may be used in any place where the dyeing of wool is carried on; for the grounds can be used in dyeing scarlet again, and thus no lose will be sustained; but always boil the cochineal, if you have no way to use up the garglings. The silk must be handled very quick in the cochineal at the first, but more slow as your liquor gets cold. It is generally handled about four hours and then let down in the liquor, till next morning, and taken out and then slightly washed and dried. This is the way to dye a scarlet, and you might make it crimson easily by blueing it down in water which contains the slightest portion of lime. First the silk is made a yellow with annato, then it gets the mordant, after which it gets the cochineal. This is the most beautiful red on silk. Any person who would like to dye a piece of scarlet silk for themselves, may do so, by using alum for mordant. A certain Dr. Berkenhout once swindled those wise savans, the Lords of the Treasury, in 1715, out of $25,000, for an alleged discovery of dyeing scarlet on cotton and linen. It was a great humbug. Dr. Barkenhout's receipt was transmitted to the London Dyers' Co., by the Lords of the Treasury. It has since been published, and it shows how adroitly the Doctor imposed upon those learned rulers.

Before cochineal became to be used, a small insect found in many parts of Europe, called kermes, was very much used with an alum preparation in dyeing red. It is a color nearly as bright and beautiful as that produced y cochineal, and far more durable. All the old tapestry in the churches were dyed with kermes. It is now out of use.

On wool salmon colors can be dyed with cochineal and quercitron bark, also oranges, only proportion your stuff to the depth of your color. Muriate of tin and tartar are put in along with the drugs.

No one can dye to shades, nut from long experience. Pure colors and lavenders, also violets may be dyed by a cochineal color first and afterwards bringing them to shade with sulphate of indigo.

Cochineal is a most splendid red paint, much used for showy drapery, but it is not so-permanent as madder lake. The following is said to be the best receipt for making it - a little superior to the one in the last number of the Scientific American: - 4 oz. fine pulverized cochineal, boil it 15 minutes in pure soft water in a tin vessel, and add two drachms of crystals of tin and 2 drachms of crystals of tartar and boil five minutes longer; take it off the fire and let it stand till cold, then pour it off into crystal vessels for two days, when a thick sediment will have fallen to the bottom, pour off the clean liquor and let the sediment be dried, and then it is fit for the painter, but ought to be kept in a tight glass vessel.

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