199 [ 175 J 



salt, with an earthy base, which, in this operation, becomes the true 

 mordant, especially as the coloring principle resides in a matter almost 

 purely resinous. 



The juice of St. John's wort, united to the mordant here mentioned, 

 gives to paper a beautiful yellow color, and to skins."* 



The comparative merits of the foregoing yellow dies with one an- 

 other, and with the inestimable quercitron bark, may be tried by prac- 

 tical diers. 



Voppy. 



The poppy color is procured by precipitating the red of bastard saf- 

 fron, t held in solution by potash. With this view, when silks arc 

 washed, drained, and put on the rods, lime juice is poured into the 

 bath, till it acquire a cherry color. It is then well stirred, and the 

 silk repeatedly worked in it, until it has acquired a sufficient color. 



To produce a lively, full poppy, the silk is wrung on coming out of 

 the first bath, which it exhausts, and is then put into a second. 



Five or six baths are requisite to impart to it a flame color. The 

 poppy color is heighten^ed by putting the silk through tepid water, 

 acidulated with lime juice. A ground of annotto, three or four shades 

 paler than aurora, is requisite for silks, before exposing them to the 

 coloring principle of the carthamus plant. 



The poppy color communicated by this last die, maybe successfullv 

 imitated by the employment of Brazil wood. 



The color thus produced is termed false poppy, to distinguish it 

 from the true. To the silk is given a good ground of annotto, by boil- 

 ing it with this die; after which it is washed, refreshed, passed through 

 alum, and then worked in a bath of Brazil wood, to which a small 

 portion of soap water has been added. J 



Black. 



The following directions are given by a late author to die silk black,§i 

 and refer to raw silk {soie, crue) which has been reeled off dry. 



The silk being cleansed, is to be bleached by being sulphured, or 

 rather to be steeped in water charged with sulphureous acid,|| then 

 washed, and passed through water in which a small quantity of soap has 

 been dissolved; then take three-fourths of the weight of silk, of gall- 

 nuts, make a strong decoction of them, and boil the silk therein for a 

 short time: let it remain in the vat for thirty-six hours, then wash and 

 wring it. The silk is so saturated with tannin, that 100 lbs. of silk, 

 thus galled, will weigh 1251bs. Put in the bath copperas and gum, ac- 

 cording to the quantity to be died, heat it, dip the silk therein, and, 

 when deeply black, put it in a trough of cold water, in which it is to 



* Extract from a paper by C. Baumach, Annales de Chimie, No. 137. 

 7 Carthamus tinctorius. 



* Chaptal, p. 485. 



«i Manuel Compl^t du. Teinturier, par M. Riffault, p. 95. Paris, 1825. 

 " The strength of the acid impretrTiation is rot mentioned 



