16 INDIGO. 



Remarks 3 ; and by comparing these patterns with others 

 Fndigo?*''^ dyed with fine Spanish indigo, the colour of those 

 done with East-India indigo appeared equally 

 clear and brilliant. 



The colours dyed in this manner are not durable 

 on cotton ; but, in consequence of the brightness 

 of the colour, are much in demand, particularly 

 upon woollen goods. 



Having reserved small portions in dry powder 

 of the East-India indigos, A, B, C, and D, I 

 mixed them together, in order to afford me a 

 sufficient quantity to form with water, lime, &c. 

 the preparation called by dyers a " blue vat," and 

 which gives a permanent colour to cotton dipped 

 therein. 



To form and manage this liquor perfectly, is 

 perhaps the most difficult branch in the dyeing 

 business, and seldom succeeds in small experi- 

 ments. To prepare this dye, vessels containing 

 s upwards of four hundred gallons are generally 

 used, contrived in such a manner as to prevent 

 the cotton from touching the dregs at the bottom 

 of the vessel, which would otherwise impair the 

 beauty of the colour. 



Judge, then, of the difficulty I had to dye in a 

 half-pint glass, the patterns I send you marked 

 Nos. 4, 5, 6. I wish you, therefore, to consider 

 these patterns as calculated only to shew the 

 durability and intensity of the colour of the East- 

 India 



