4

DYEING AND CALICO PRINTING.

No records remain regarding the operations carried out and processes inventedby the latter, but it is certain that they were acquainted with the use of suchsubstances as madder, woad, nutgalls, and alkanet root, and with theapplication of blue and green vitriol, alum, and even some salts of lead.According to Dioscorides and Pliny, who lived in the ist century, indigo wasknown in Europe, and although scarce, was regularly imported ftom India,whence its name is derived. The natives precipitated and colledted in a drysolid form the colouring matter of indigo, and, what must have been a muchgreater difficulty, they afterwards discovered the means of dissolving it andrendering it capable of being permanently fixed upon the substances intendedto be stained or dyed with it; an effedt which the Greeks and Romans do notappear to have ever produced, though they knew how to powder and applyindigo as a paint.

“It appears that wool* was never worn in China but as a substitute for fur,and that cotton and silk, being the only substances ever dyed by the inhabi-tants, received all their colours from vegetable tindlorial matters; that thesecolours were principally red, blue, violet, and what is called a woad colour;and that under the three first dynasties the business of dyeing was chieflypradtised by the female part of each family for its own particular use : and itprobably continued to be practised without anything like principle or scienceuntil near the end of the 7th century, when the Chinese, discarding their own,borrowed the art and means of dyeing which were then in use among theHindoos and Persians; and it is said that alum and copperas, which the Chinesedid not use before, were among the means so borrowed, a fad which renders itprobable that there was little, if anything, in the Chinese art of dyeing ofwhich the loss need now be regretted.

“ It appears, however, that long before this time a knowledge of the uses ofalum and of iron salts in dyeing had spread from Hindostan and Persia west-ward to Egypt, and thence to Greece and Rome. Bergmann, indeed (“ DeConfedt. Alum”), and, after him, Beckmann (in the “ Gottingen Memoirs”),have represented the alum of the ancients as differing from the crystallised saltso-called by the moderns, and have supposed that the varieties of alum men-tioned by Dioscorides. were staladlites containing but little alum and consistingchiefly of calcareous earth, which, in certain proportions, will hereafter appearto be a very useful addition for most of the colours depending on an aluminousbasis. Nature, however, does produce some, though but little, crystallisedalum, particularly in Egypt and some parts of Asia, and it probably was in thisstate that its good effedts in dyeing had been first observed, before mankindwere led to the means and operations since employed for separating andcolledling it from the various aluminous ores. Bergmann says that ‘ thefadtitious salt which is now called alum was first discovered in the easterncountries.;’ and that ‘among the most early works established for the prepa-ration of alum we may justly number that of Roccho, a city in Syria, nowcalled Edessa ; hence the appellation of roche alum (see vol. i., p. 339, of theEnglish translation of his Essays).’ He adds that ‘ Bartholomew Perdix, orPernix, a merchant of Genoa, who had been at Roccho, discovered the matrixof alum in the island of Ischia, about the year 1459, and established amanufadtory there; at the same time, John de Castro, who had visited the

* Menjoires Concernants I'Histoire, les Sciences, les Arts, Ies Mceurs, &c., des Chinois.