306 VEGETABLE SUBSTANCES. 



shade. Practical dyers, however, class these likewise 

 under the title of mordants. 



Almost all the metallic oxides have an affinity for 

 the fibres of cloth, but only two are extensively used 

 as mordants, these are the oxides of tin and of iron. 

 Solutions of tin in acids, sulphate of copper, acetate 

 of lead and of copper, chloride of sodium (common 

 salt in a dry state), alum, lime, tan, and tartar are the 

 substances principally used as mordants. 



Their effects in topical dyeing constitutes that 

 "truly wonderful art," the art of calico-printing 1 , or of 

 communicating different colours to particular spots 

 or figures on the surface of cotton or linen cloth, 

 while the rest of the texture retains its original white- 

 ness. This art originated in India, where it has 

 been pursued, with little alteration, for more than 

 two thousand years, it having been practised during 

 all that period in a most elaborate manner by the 

 Hindoos. The account given of the mere preli- 

 minary steps affords an example of the complicated 

 and tedious processes in which these people love to 

 involve their arts, while it will offer a slight specimen 

 of the many subsequent operations needed for the 

 completion of the work. 



" The cotton cloths, on being brought from the 

 weavers partly bleached, were worn next to the skin 

 by the dyer, or some members of his family, during 

 the space of eight or ten days, after which time the 

 stuff underwent several macerations in water mixed 

 with goats' dung, accompanied by frequent interme- 

 diate beatings, washings, and dryings in the sunshine. 

 The cloth was then soaked for a considerable period 

 in a mixture of the mucilaginous astringent fruit of 

 the yellow myrobalans with curdled buffalo's milk ; 

 being thoroughly penetrated and impregnated there- 

 with, it was taken out from the liquor and well 



