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LIIL MeJJrs. Collakd and Fraser's Trocefs for pre* 

 faring the Weld Yellow i„ 



JL FI ERE is not to be found, cither In the vegetable or 

 mineral kingdoms, any other fubitance which yields fo ele- 

 gant a yellow colour as the weld, or, as it is written by fome, 

 would, or dyer's weed. The welf) is of the rcftdian tribe, and 

 is cultivated with care in Kent, 1 lerefordfhire, and many other 

 parts of tiie kingdom. The principal coniumers are dyers, 

 calico-printers, and colour-makers. Tne plants are dried by 

 the growers, tied up in parcels weighing from 30 to 50 pounds 

 each, and are fold, to ufe the language of the trade, at fa 

 much a bundle. 



This is a very injudicious practice; for it is the fmall feeds 

 of the plant only which afford the colouring matter, a great 

 portion of which are fliaken out in the package, and even in 

 moving the bundles from one place to another. Befides, the 

 plant altogether occupies fo much room, that the carriage of 

 the uielefs (talks for a hundred miles, by land, amounts to 

 more than five per cent, upon the article; whereas the feeds, 

 in a quantity occupving a fpace of fix feet fquare would by 

 no means fill a half peck meafure. 



The weld yellow is a water-colour, principally ufed by 

 paper-hanging manufacturers for elegant work. An oil co- 

 lour has never been prepared from the weld. A preparation 

 of weld yellow in oil would be a valuable acquifition ; for the 

 patent oil colour, made from a very old recipe, by fufing the 

 oxide of lead with the muriate of ammonia in the proportion 

 of about one pound of the former to three ounces of the latter, 

 appears as vile as brick dull when compared to the weld 

 yellow. 



The weld yellow made in London is fold in hard lumps, 

 and muft be ground before it is fit for ufe. Now it is well 

 known that every colour fufTers, in fome degree, by that ope- 

 ration. By the following procefs the moll beautiful weld 

 yellow may be prepared, which will fall into a fine powder, 

 and will want no grinding. 



Take of pure carbonate of lime (fine warned whiting) any 

 given quantity, e.g. let it be four pounds ; put it into a copper 

 boiler, and add to it four pounds of foft water : put a fire 

 under the copper and raife it to a boiling heat, and keep ttir- 

 ring with a deal flick till the whiting be completely divided, 

 and forms with the water a confidence quite fmooth. Then 



♦ Communicated by Metirs. CollarJ and Frafcr. 



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