172 DYES 



over the rotating roll, receiving color from the engraved design ; 

 in this way, the color pattern is automatically printed on the 

 cloth with perfect regularity. In cases where the fabrics do 

 not unite directly with the coloring matter, the design is supplied 

 with a mordant and the impression made on the fabric is that 

 of the mordant. Then the fabric is transferred to a dye bath 

 and the mordanted portions, represented by the design, unite 

 with the coloring matter and form the desired color patterns. 



Unless the printing is well done, the coloring matter does 

 not thoroughly penetrate the material, and only a faint blurred 

 design appears on the back of the cloth ; the gaudy designs 

 of cheap calicoes and ginghams often do not show at all on 

 the under side. Such carelessly made prints are not fast to 

 washing or light, and soon fade. But in the better grades of 

 material the printing is well done, the color designs are fairly 

 fast, and a little care in the laundry suffices to eliminate any 

 danger of fading. 



Color designs of the greatest durability are produced by 

 the weaving together of colored yarns. When yarn is dyed, 

 the coloring matter penetrates to every part of the fiber, and 

 hence the patterns formed by the weaving together of well- 

 dyed yarns are very fast to light and water. 



If the color designs to be woven in the cloth are intricate, 

 complex machinery and skillful handwork are necessary ; hence, 

 patterns formed by the weaving of colored yarns are expensive 

 and less common than printed fabrics. 



