DYEING. 



shortly after the conquest of Mexico. 

 The Spaniards having- observed that the 

 Mexicans employed cochineal in painting 

 their houses, and in dyeing their cotton, 

 gave their government an account of 

 it ; and in the year 1523, Cortes was 

 ordered to promote the increase of the 

 valuable insect from which it is ob- 

 tained. 



The natural colour obtained from co- 

 chineaTis only a dull crimson ; but soon 

 after it was known in Europe, an emi- 

 nent chemist, of the name of Kepler, 

 found out the present process for dye- 

 ing scarlet with it, by means of a solu- 

 tion of tin, and carried the secret to 

 London, in the year 1543 : this process 

 was first used at Bow, and hence the 

 scarlet produced by it was called the 

 Bow dye. 



A Flemish painter, called Gluck, got 

 possession of the secret, and communi- 

 cated it to Giles Gobelin, who establish- 

 ed a manufactory of it in the place in 

 France which still bears his name. This 

 undertaking was deemed so rash, that it 

 was termed Gobelin's folly : but his as- 

 tonishing success at length induced peo- 

 ple to suppose that he had made a com- 

 pact with the devil, from which the appli- 

 cation of the term goblins to evil spirits 

 is probably derived. The knowledge of 

 this process afterwards spread through- 

 out all Europe. 



The discovery of this mode of dyeing 

 scarlet may be considered as the most re- 

 markable XT& in the art of dyeing. The 

 ancients applied the name scarlet to a co- 

 lour obtained from kermes, which was 

 much inferior in beauty to the colour 

 procured from cochineal. 



Dufay, Hellot, Macquer, and Berthol- 

 let, were successively charged by the 

 French government with the care of im- 

 proving the art of dyeing. Dufay was the 

 first who entertained just, though imper- 

 fect, ideas of the nature of colouring sub- 

 stances, and the power by which they 

 adhere ; he examined certain processes 

 with great sagacity, and established the 

 surest methods that could at that time be 

 employed, for determining the goodness 

 of a colour. Hellot published a metho- 

 dical description of the processes used 

 in dyeing wool, which even now is the 

 best treatise we have on the subject. 

 Macquer has given an exact description 

 of the processes employed in dyeing 

 silk ; he has made us acquainted with 

 the combinations of the colouring princi- 

 ple of Prussian blue ; he has endeavour- 

 ed to make an application of it to the 



art of dyeing, and has given us a process 

 for communicating the most brilliant co- 

 lours to silk by means of cochineal. He 

 intended to publish a general treatise on 

 the art of dyeing, of which he gave the 

 prospectus in 1782; but his death, which 

 took place in 1784, prevented the execu- 

 tion of any part of the work. 



Berthollet succeeded Macquer; his 

 treatise on dyeing is one of the best epi- 

 tomes on the subject; and chemistry, 

 and the arts of dyeing, and of bleach- 

 ing, have been much indebted to his la- 

 boars. 



In his theory of dyeing, he refers all 

 the combinations produced in the forma- 

 tion of colours to the laws of chemical at- 

 traction ; and all the changes, which the 

 colouring particles undergo, to the con- 

 junction of the elements of the new com- 

 bination. The first effect of the attrac- 

 tion he considers as analogous to the 

 formation of neutral salts ; the second to 

 combustion, putrefaction, and many other 

 operations ot nature. 



Besides the authors mentioned, Chap- 

 tal, D'Apligny, D' Ambourney, and HaufF- 

 man, in France, have published treatises 

 on the art of dyeing, which have much 

 contributed to its improvement. In Swe- 

 den, Scheffer alone has written on the 

 subject; his work is accompanied with 

 notes by the celebrated Bergman. In 

 Germany, experiments in different pro- 

 cesses of dyeing have been published by 

 Beckmann,Poerner,Vogler, and Franche- 

 ville. In England, two very valuable es- 

 says on dyeing, by Delaval and by Hen- 

 ry, have appeared ; to which may be 

 added, the excellent treatise on the phi- 

 losophy of permanent colours, by Dr. 

 Bancroft. ,-,' 



Qftlie Attractions of Colouring Substances. 



A variety of theories have been pro- 

 duced by ingenious men, to account for 

 the effects of dyeing. Bergman seems 

 to be the first who referred them entirely 

 to chemical principles ; and this opinion 

 is so consonant to reason, that it is now 

 universally adopted. 



Dyeing, then, isto be considered mere- 

 ly as a chemical process ; but in order that 

 it may succeed, it is necessary that the 

 colouring matters should be dissolved in 

 some fluid, (for in their solid state no at- 

 traction takes place between them and 

 the stuff,) and that their attraction to the 

 fluid should be less than that to the stuff. 

 Besides, the colouring matters being 

 brought within the proper distance for 



