DYEING 



and soaked, for an hour and a half, in a 

 solution of a quantity of sulphate of cop- 

 per equal to one fourth of the weight 

 of the stuff; it is then thrown, without 

 being washed, into a solution of soap, 

 in the same proportions : after being 

 well stirred, it is boiled in it, for near- 

 ly an hour, and then well washed and 

 dried. 



If a deeper colour is wanted, the stuff 

 is not alumed, but two pounds and a half 

 of weld are used for every pound of the 

 stuff, for each of which a drachm of ver- 

 digrise mixed with a part of the bath is 

 added ; in this bath it is dipped and work- 

 ed, till it has acquired an uniform colour ; 

 it is then taken out of the bath, and a lit- 

 tle ley of soda poured in ; after this it is 

 again returned into the bath, kept there 

 a quarter of an hour, and then taken out, 

 wrung, and dried. Other shades of yel- 

 low may be obtained, by varying the 

 proportion of the ingredients ; a lemon 

 colour may be procured, by using only 

 one pound of weld for every pound 

 of cotton, and by diminishing the proper- 

 tion of verdigris, or using alum as a sub- 

 stitute. 



Dr. Bancroft directs a method for dye- 

 ing cotton yellow, which he asserts to be 

 much cheaper, and which appears better 

 in several respects, particularly as to the 

 mordant. It is as follows : 



The mordant to be used is the acetite 

 of alumen, formed by dissolving one 

 pound of sugar of lead, and three pounds 

 of alum, in a sufficient quantity of warm 

 water. In this liquor, heated to 100, the 

 cotton is to be steeped two hours,after be- 

 ing first properly rinsed. It is then taken 

 out and moderately pressed over a ves- 

 sel, to prevent waste of the liquor. It is 

 then dried in a stove heat, and after being 

 again soaked in the aluminous solution, 

 is wrung out a second time and dried : it 

 is then barely wetted with lime-water, 

 and afterwards dried ; and if a full and 

 bright colour is wanted, it may be neces- 

 sary to soak the stuff again in the diluted 

 aluminous mordant, and, after drying, to 

 wet it a second time with lime-water : 

 after it has been soaked for the last time 

 it should be well rinced in clean water, to 

 separate the uncombtned portion of the 

 mordart, which might injure the applica- 

 tion of the colouring matter. By the use 

 of the lime-water, a greater proportion of 

 alumen combines with the stuff, as well 

 as a certain portion of lime. 



In the preparation of the dyeing bath 

 from twelve to eighteen pounds of quer- 

 citron bark are inclosed in a bag, for 



every hundred pounds of the stuff, vary- 

 ing the proportion according to the shade 

 required. The bark is put into the water 

 while cold, and immediately after the 

 stuff is immersed, and agitated or turned 

 in it for an hour or an hour and a half, 

 during which the water should be gra- 

 dually heated, and the temperature rais- 

 ed to 120. At the end of this time the 

 heat is increased, and the dyeing liquor 

 brought.to a boiling temperature ; but 

 at this temperature the stuff must only 

 remain in it for a few minutes, because 

 otherwise the yellow assumes a brownish 

 hue. The stuff, having thus acquired a 

 sufficient colour, is taken out, rinsed, and 

 dried. 



Many attempts have been made to imi- 

 tate the shade of yellow which nankeens 

 possess ; but none have hitherto succeed- 

 ed, so as to produce a colour whose dif- 

 ference from the real nankeen could not 

 be in general distinguished at first sight ; 

 or in the very few instances where this 

 was at all doubtful, a little wear soon be- 

 trayed this deception. Chaptal has recom* 

 mended a colour procured from salt of 

 iron for this purpose; and in the processes 

 of others, iron in general has been the co- 

 louring substance used ; but a colour 

 from iron has the evident defect of get- 

 ting black stains from the least touch of 

 any astringent liquor, to which it is per- 

 petually liable wherever tea is used. It 

 is therefore useless to insert receipts for 

 a colour which never yet came suffi- 

 ciently near what it was intended, to pro- 

 duce the least competition in the market 

 with the real article. 



Nankeen is made of cotton, whose co- 

 lour is naturally such as we see it ; some 

 of the best grows in Bhaugalpore in the 

 East Indies; it would be an object well 

 worth the attention of the cotton plant- 

 ers in the West India Isands, to get over 

 plants or seeds of this species of cotton, 

 to raise it for the English market. Per- 

 haps the Bhaugalpore cotton might be 

 imported from the East cheap enough for 

 the use of our manufacturers, which 

 would save the nation much of the large 

 sums that go out of it annually for the 

 purchase of nankeens. 



Of dyeing Wool green. 



Having given an account of the most 

 approved processes for dyeing the four 

 simple colours, black, red, blue and yel- 

 low, we now proceed to the compound co- 

 lours ; which are so called, because in ge- 

 neral they are produced in dyeing by mix- 





