The Dyer's Guide. Chapter IV. On Scouring and Dyeing Wool. On dyeing wool scarlet.

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,

Scarlet owes its beauty to a solution of tin in muriatic acid. For this purpose some use muriate of ammonia, commonly called sal-ammoniac, others use common salt.

It is of little consequence whether common salt or sal-ammoniac be used: different preparations are employed by different persons. The author has found the following to answer every expectation.

Melt an ounce of grain tin in an iron ladle, till an oxide is formed on the surface; then pour it from a height or distance into cold water. Pour the water from it, and it is fit for use, being then called feathered tin. Put this tin into a glass vessel or stone jar, and add to it eight ounces of nitric acid, eight ounces of water, half an ounce of sal-ammoniac, and two drachms of nitrate of potash. This preparation is better if made some time before it is used; it is a compound of nitrate and muriate of tin.

Should any one prefer a pure muriate of tin, the method of making it will be found in the last Chapter, in observations on crimson and scarlet upon silk.

Into a copper of cleared boiling water, the heat being reduced, and having the worsted wetted out ready; for every pound of which (dry) put two ounces of cream of tartar or white tartar in powder, and one drachm and a half of cochineal in powder. When the liquor is ready to boil, add two ounces and a half of the first-mentioned solution of tin, which immediately changes the colour; stir it well: as soon as the liquor boils put in the worsted, and boil it till the colour of the cochineal is taken up by it. The worsted must now be taken out, when it will be of a flesh-colour, the water in the copper having lost its colouring matter. To finish the worsted, another quantity of clean water is made warm, into which six drachms and a half of cochineal are to be put; just before it boils, two ounces of the same solution of tin are to be poured in, the liquor undergoing a similar change as before. The worsted is again put in, and boiled till it has imbibed the colour; it is then taken out, wrung, and rinsed in clean water, when the scarlet is in perfection.

One ounce of cochineal to a pound of wool, will impart a colour sufficiently deep, if managed according to the method above described, no colour being left in the remaining liquor.

For many shades of scarlet it will be, however, necessary, and, in a fresh liquor, to add either a certain portion of turmeric or young fustic, to give the scarlet that fiery red which some scarlets have. If not in an entire fresh liquor, a part of the old liquor must be taken out before the yellow is added.

When it is wished to dye a regular series of scarlet shades in worsted, half the quantity or less, for some of the lightest, will be sufficient of the solution of tin, the tartar, the cochineal, &c. The worsted should be separated into divisions corresponding with the shades required; the lightest is of course to be done first: if any deficiency be in the shade, it may have another dip. This deficiency is easily perceived, and a very little practice will enable the operator to assort them perfectly.

It should he noted, that the vessel most proper to dye scarlet in ought to be made of block tin; such as are used by the scarlet dyers for the East India Company.

When woollen cloth is to be dyed scarlet, to every hundred pounds of cloth put six pounds of tartar and eighteen pounds of the solution of tin at first; the same quantity in the completion; and in each operation, six pounds and a quarter of cochineal.

For the accommodation of those who would make small experiments, one ounce of cream of tartar, six ounces of solution of tin, and one ounce of cochineal, may be used for every pound of worsted or cloth, putting two-thirds of the solution of tin and the tartar, and a quarter of the cochineal, into the preparation, and the remainder to the completion.

Observe, that although we have given processes for dyeing woollen cloth crimson as well as scarlet, yet crimson may be obtained in another way: for alum, the salts in general with an earthy base, and the fixed and volatile alkalies, possess the property of changing the colour of scarlet into crimson, the natural colour of the cochineal. The cloth which is dyed scarlet has only to be boiled, therefore, for about an hour, in a solution, more or less charged with alum, according as a deeper or lighter crimson is wanted. When a piece of scarlet has any defects, it is set apart for crimson. Soap and potash will also produce crimson from scarlet, but not of so bright a colour as from alum. Hence also we learn the necessity, in, at any time, working scarlet cloth, to avoid boiling it with soap or pot-ash, &c. if we desire the scarlet to remain.

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