CHAP. 42.—THE COLOURING OF TISSUES.
In Egypt, too, they employ a very remarkable process for the colouring of tissues. After pressing the material, which is white at first, they saturate it, not with colours, but with mordents that are calculated to absorb colour. This done, the tissues, still unchanged in appearance, are plunged into a cauldron of boiling dye, and are removed the next moment fully coloured. It is a singular fact, too, that although the dye in the pan is of one uniform colour, the material when taken out of it is of various colours, according to the nature of the mordents that have been respectively applied to it: these colours, too, will never wash out. Thus the dye-pan, which under ordinary circumstances, no doubt, would have made but one colour of several, if coloured tissues had been put into it, is here made to yield several colours from a single dye. At the same moment that it dyes the tissues, it boils in the colour; and it is the fact, that material which has been thus submitted to the action of fire becomes stouter and more serviceable for wear, than it would have been if it had not been subjected to the process.