THE STORY OF ARTIFICIAL SILK ssi The first thing that must be done, before a new silk mill is built, is to analyse the water. Unless the water is pure, the silk will be dull and must be sold at a low price. Any investor, before he puts money into a new Artificial Silk enterprise, should ask if the water is suitable. Great care, too, must be taken in the drying of the filaments. They must not be dried too quickly. They are like furs in this respect. If they are dried too quickly, they will have a yellowish stain. Green stains, as well, sometimes appear because of a fault in the washing. An Artificial Silk mill requires its own Special climate. It needs a certain degree of humidity, just as a cotton mill does. It is a strange fact that the threads are more lustrous when they are dried under tension. This fact was first noticed in the mercerizing of cotton. The reason for this is that when a thread is stretched, the surface is not broken. It retains its gloss. Viscose silk has a bright silvery lustre. Acetate silk has a glistening metallic lustre. Cuprammonium silk has a glassy appearance. 6°