DYEING. 



Jhg coarse woollen stuffs. To produce 

 this red, the stuffs are first boiled for two 

 or three hours with alum and tartar ; they 

 are then left to drain, slightly wrung out, 

 and then put into a linen bag, and cur- 

 ried to a cool place, where they are to 

 remain a few days. Some recommend 

 fire ounces of alum and one of tartar to 

 each pound of wool j by increasing the 

 proportion of tartar, a deep and perma- 

 nent cinnamon colour is produced instead 

 of red ; others advise to use only a se- 

 venth part of tartar. The madder bath 

 should not exceed the temperature 

 which the hand can bear; if let to bo'd, 

 the colour will be different from that re- 

 quired. When the water is at this heat, 

 Hcllot recommends half a pound of 

 grape madder to be put into it for every 

 pound of wool to be dyed.' It is to be 

 well stirred before the wool is introduc- 

 ed, which should remain in it for an hour 

 without boiling, except for a few minutes 

 towards the end of this period, to make 

 the combination of the colouring mut- 

 ter with the stuff more certain. 



Madder reds are sometimes rosed, as 

 it is called, with archil and brazil wood. 

 In this way they become more beautiful 

 and velvety, but the brightness thus gi- 

 ven is not permanent. 



When sulphate of copper is employed 

 as a mordant, the madder dye yields a 

 clear brown, somewhat inclined to a yel- 

 low ; when solution of tin is used, the 

 tint, according to Berthollet, is some- 

 what brighter than that obtained by the 

 common method, but is always more in- 

 clined to yellow or fawn colour. 



The red procured from kermes is finer 

 than that from madder. The kermes is 

 an insect found on a small species of live 

 oak in Languedoc, Spain, Portugal, and 

 other places ; the females alone are used, 

 they are of the shape and size of a pea, 

 and of a reddish brown colour. 



To dye woollen yarn with kermes, it is 

 first boiled half an hour in water with 

 bran ; then two hours in a fresh bath, of 

 one fifth of Roman alum, and one tenth 

 of tartar dissolved in sour water; after 

 this, it is left in a linen bag for some days 

 in a cool place. To obtain a full colour, 

 as much kermes as equals three fourths, 

 or even the whole of the weight of the 

 yarn, is put into a warm bath, and the wool 

 is put in at the first boiling. As cloth is 

 less dense than wool, either spun or in 

 the fleece, it requires one fourth less of 

 the salts in boiling, and of the kermes in 

 the bath. 



VOL. IV. 



The scarlet made by kermes was c*ll- 

 ed scarlet in grajn, from the insect re- 

 sembling a grain ; it has much less bloom 

 than that procured from cochineal ; but 

 is more permanent, and *-pots of grease 

 may be discharged from it without inju- 

 ry. Since the art of heightening the co- 

 lour of cochineal by solution of tin had 

 been discovered, kermes has not been 

 much used. 



The scarlet produced by the prepara- 

 tion of cochineal just mentioned is es- 

 teemed the finest and most splendid of 

 any. Cloth to be dyed with it is first 

 submitted to the following bath : six 

 pounds of tartar are infused in the water 

 made warm, for every hundred pounds of 

 the cloth ; the bath is then stirred brisk- 

 ly, and when the heat has increased a little 

 more, half a pound of powdered cochi- 

 neal is to be added, and the whole is then 

 to be well mixed; immediately after- 

 wards, five pounds of a very clear solu- 

 tion of tin are to be poured in, and care- 

 fully mixed. When the bath begins to 

 boil, the cloth is introduced, and briskly 

 moved for two or three turns, after which 

 it is moved more slowly. The boiling 

 having continued for two hours, the 

 cloth is taken out, exposed to the air, and 

 carried to the river to be well washed. 



The cloth is afterwards passed through 

 a second bath for the reddening; to pre- 

 pare which, the boiler is to be first emp. 

 tied, and again filled with water; and when 

 this has just reached the boiling point, 

 five pounds and three quarters of cochi- 

 neal, powdered and sifted, are to be add- 

 ed. Thee are to be well mixed ; and 

 some time afterwards, when a crust that 

 forms on the surface opens of itself in 

 several places, 13 or 14 pounds of solu- 

 tion of tin are poured in. Should the 

 bath after that rise above the edge of the 

 boiler, it may be cooled with a little wa- 

 ter. The bath being wrll mixed, the 

 cloth is put in, and turned quickly two or 

 three times. It is then boiled in the bath 

 for an hour, taking care to keep it un- 

 der the surface. It is afterwards taken 

 out, exposed to the air, and, when cool, 

 washed in the river, and dried. 



Some dyers do not remove the cloth 

 out of the first bath ; but merely refresh 

 it, and perform the operation of redden- 

 ing in the same bath. In this method, 

 the infusion of cochineal, made in ascpa- 

 rate ressel, and mixed with a proper 

 proportion of tin, is added. By con- 

 ducting the process in this way, the scar- 

 let is supposed to be equally fine, and 



Kk 



