A Treatise on Calico Printing, Of Colour-Making, Concerning YELLOW &c.

A Treatise on Calico Printing, VOL. I-II
Printed for C. O'Brien, Bookseller, Islington, and fold by Bew, Paternoster-row: Richardson, Royal Exchange: Murray, Fleet-Street: And the Booksellers of Manchester, Glasgow, Dublin, &c.


(68) The action of allum and lime on the colouring substances is similar to that of lime or alkalies on indigo. —  See further on.

If allum be boiled in a copper vessel, the liquoi will be impregnated with copper, which vol. alk will detect.

(69) Such practices helped to forward the failure of Livesy and Co. — See further on, note 8
The solutions of allum, sugar of lead, and tartar united, is the agent for procuring yellow from  weld; tartar is however not now much used. The natural operation here being similar to that of maddering, excepting the colouring matter being yellow instead of red. (68) Various articles are sometims used as substitutes, but none excels it. The New-England oak 2 bark, used by many in Lancashire may however be mentioned as the best.

A weed called by some Ladies Bed-Straw (see the sheet with the table for proportions) has had a little undeserved repute for bringing up several colours at once: it may nevertheless serve as a substitute for weld. The root gives a red. —  Several fields near Bow in Middlesex are appropriated for the cultivation of this plant.

The varieties of drabs, teas, clays, dull-greens, &c. are easily procured by varying the proportions of sumach, fustick, &c. as already stated.

An orange or snuff-colour, is procurable by not letting the maddering come up to a scald, so that the red is barely produced, and then welding it. It may be subjoined, that a repetition of maddering or welding by adding various salts or calces to what remains, will produce various effects. Variegated effects are likewise to be produced by welding first, then printing an after-course and maddering it: but these, how ever, are only tricks to be pursued with mode ration. (69)

It has been observed (see note 30, maddcring) thata philosophical mind might come near to some proper criterion for ascertaining the quantity of madder, &c. merely requisite in all cases. The hint there given may possibly be improved by the practice of dyeing, where the weight of the stuff that is to be dyed, regulates the weight or measure of the articles that procure the dye. There are however great obstacles to such ascertainment in Callico-printing: but, if only for experiment sake, cloth might be weighed before and after being printed, and the difference in weight acquired by printing, made to regulate the quantity of madder, weld, &c. taking info account the dry and wet state of the cloth, the thickening, &c. But, at any rate, the superquantity of the colouring articles might, by certain processes, be seperated from  whatever else that may necessarily be left in the copper of the thickening, tightening, &c. and the madder, weld, &c. not taken tip, be separated in a pure state (this at a future time will probably be specified, though deemed needless now, as the agency of chymistry  must be brought in, in a rather particular and operose manner. The writer is aware, and has mentioned, (see maddering) that, in common, this super-quantity is made use of for inferior purposes; and even in the colouring house in making yellow, &c. but something like what is hinted as above, would be of much better advantage.

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