=There are many beautiful colored silks.= Silk is usually dyed (Fig. 79) in the yarn in hanks. The poor qualities, however, are dyed after the silk is woven into the piece. Silk is dyed by dipping the skeins or yards of silk in great vats of dye. For dyeing, the coal-tar products (aniline dyes) are used. Did you know that coal could produce such beautiful colors? That is a long story of the many wonderful things which can be made from tar. Do you know that 25 per cent of the weight of the raw silk is made up of the gummy substance? The dyer boils out some of the gum; and, if he wishes to produce cheap silks and make much money, he makes up for the weight of gum boiled out, by using tin. The silk is dipped in bichloride of tin or other substances; and it takes up, or absorbs, until sometimes it weighs twice or even four times as much as the boiled-off silks. This tin is bought for silk. Women who do not know think they are buying heavy silk and are getting a good quality because it is so heavy. This solution of tin rots the silk, and, when the silk comes in contact with light and air, it crumbles away. Perhaps you have at home a sample of silk which has done this. Marjorie's Cousin Ann saw some petticoats of silk which went to pieces just hanging in a closet. Sometimes that happens when store keepers keep the petticoats for some time. One can see the holes by holding the silk up to the light. In order to know what one is buying one must study about materials and about how they are made. [Illustration: _Courtesy of Cheney Bros._ FIG. 80.--Warping or preparing silk for the loom.] =Have you ever seen a picture of silk being dyed in the skein?= Marjorie's cousin says it is done by machinery. See how many skeins are on the big wheel, or drum as it is called. As it turns, the skeins are dipped in the vat of dye. [Illustration: _Courtesy of Cheney Bros._ FIG. 81.--Silk weaving on a hand loom in Japan.]