THE BLUE DYES OF CHINA AND INDIA. 121 



Borate from Cabreria and Binconada gave 42-20 per cent, boracic acid. 

 From tbe Pascana of Pedro Castro, 21-25 ; is of a yellowish colour (probably 

 from chrome) ; a white matter from Tronco, Challapozo, and Challapozito, 

 borate of lime, 5 per cent. White matter from Aguada del Sur, no borate, 

 principally sulphate of lime ; but, one league distant, good borate is met 

 Avith. At the Puquios of Quilliagua is a polyhalite, composed of sulphates 

 of lime, magnesia, and potash, with salt. The salt found near Matilla, 

 called San Sebastian, is threnardite. Under the calichales of Challa, tbere 

 is much glauberite. In Zapiga. under the nitrate, borate is met with, con- 

 taining borate of lime, 35-17; borate of soda, 20-21. Borate, between 

 Independencia and Colombia, contains 43-139 boracic acid. Mr. George 

 Smith made borax from it in Iquique. He sent borate to the United States, 

 where it was examined by Hayes, and obtained the name of Hayescine. 



Test for Borate. — When in small quantities, macerate in alcohol, adding 

 a little sulphuric acid ; evaporate the solution, in firing it, and, if there be 

 the merest trace of boracic acid, it will colour the flame green. 



THE BLUE DYES OF CHINA AND INDIA. 



BY M. C. COOKE. 

 CHINESE BLUES. 



The practice of dyeing blue cloths is very ancient in China. It is 

 recorded as early as the reign of the Emperor Hoang-ti, who died B.C. 

 2598. The Chinese books call the plants that yield indigo by the name 

 of Ian. Of these there are numerous species, and their identification is still 

 by no means satisfactory. The fresh leaves of the different species of Ian 

 are extensively used in dyeing light blue. I have been informed by a silk 

 dj r er that he received some time since a light blue silk scarf from China, in 

 the colour of which he took considerable interest. He made every effort 

 to discharge a portion of the colour, but without success. The dye was 

 one with which he was entirely unacquainted, and, after making several 

 experiments upon the scarf, he is positive that it was not an indigo dye. 

 Hence we may conclude that our silk dyers have yet something to learn 

 from those of China in the art of dyeing blue. 



Lan, of Canton. — It is difficult to fix the botanical name of this Ian, 

 which is described as an acanthaceous plant. It is very common in the 

 provinces of Kouang-toung, of Fo-kien, and Tche-kiang. The fresh leaves 

 are used for light blue. When about to dye, the cloth is dipped in cold 

 water, dried in the sun, and dipped in a warm bath of leaves of Ian, into 

 which a small quantity of lime juice has been poured. When used in the 

 form of paste, the Chinese generally take precautions to keep it in a moist 

 state. Dry indigo is seldom used for blue dyes in any portion of the 

 Chinese empire. 



