The Dyer's Guide. Chapter VI. On Dyeing Cotton And Silk. On dyeing silk a fine crimson. Composition for dyeing silk scarlet or crimson with cochineal.

The Dyer's Guide
Being a Compendium of the Art of Dyeing
Linen, Cotton, Silk, Wool, Muslin, Dresses, Furniture, &c. &c.

With The Method of
Scouring Wool, Bleaching Cotton, &c.
Directions for Ungumming Silk, And For Whitening And Sulphuring Silk And Wool.
And Also
An Inttroductory Epitome of The Leading Facts in Chemistry, As Connected With The Art of Dyeing.

By Thomas Packer,
Dyer and Practical Chemist.

"Cet arte est un des plus utiles et des plus merveilleux qu'on connoisse."
- Chaptal.

"There is no art which depends so much on chemistry as dyeing."
- Garnett.

Second Edition,
Corrected and Materially Improved.

Printed for Sherwood, Gilbert, And Piper,

Silk intended for the crimson of cochineal should have only twenty pounds of soap to one hundred pounds of silk, and no azure, because the natural yellow of the silk which remains is favourable to the intended colour.

The silk is to be strongly alumed and left in the alum from seven to eight hours, then washed and twice beetled at the river. Remember how the alum is to be worked, as to the manual part.

While this is doing, a liquor is to be thus got ready: take of blue and white galls from one to two ounces to each pound of silk, let them be well powdered and sifted; of fine cochineal, also well powdered and sifted, from two to three ounces, for every pound of silk; put these articles into pure soft water, and in a boiler made of grain-tin, (and not in what is commonly called tin, which is iron covered with tin, and which would utterly spoil the dye.) Neither would copper or brass suit as well as grain-tin. This has been observed before, (page 84.) in the article on dyeing wool scarlet. It ought, nevertheless, to be stated, that such tin boilers are difficult to be made of a certain size, and being liable, besides, to be melted without great care. Many dyers therefore, still use copper boilers. When the cochineal and galls have boiled you add to the liquor for every pound of cochineal, about one ounce of solution of tin, which is called composition, and is made in the following manner:

Composition for dyeing silk scarlet or crimson with cochineal.

Take one pound of nitric acid, two ounces of muriate of ammonia, six ounces of fine tin, prepared as mentioned under dyeing wool scarlet, water twelve ounces.

The muriate of ammonia, the prepared tin, and the water, are put into a stone jar, to which the nitric acid is added, and the whole left to dissolve.

This composition contains much more tin and sal-ammoniac than is used for the scarlet of cochineal upon wool; it is, however, absolutely necessary.

An ounce of this composition, for every pound of silk, is to be added to the galls and cochineal when boiling. The boiler is then cooled down a little, the fire-door thrown open, the silk put in and worked from five to seven times, when the silk will have become pretty even as far as it is dyed. The copper is now again to be brought to boil; it should continue boiling, and the silk kept turning, for two hours; the fire is then taken from under the copper, and the silk is immersed entirely and left all night, or for seven or eight hours at least; it thus takes a full half shade. In the morning it is washed, twice beetled, wrung as usual, and hung up to dry.

The least tincture of sulphate of iron in the water saddens the crimsons, takes off their yellow, and gives the violet cast; but if too much of the yellow is carried off, it may be restored by fustic. Nothing but sulphate of iron will sadden grain scarlets, logwood being quite useless for this purpose; sulphate of iron darkens greatly with galls. Macquer.

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