In point of quality wool belongs next to cotton, although in price there is a long distance between them. A scaly structure on the surface of wool (Fig. 59), especially marked in sheep's wool, gives it virtues possessed by no other fiber. It is by reason of these scales that wool mats together, that air is held in the spaces of a woolen garment, that it absorbs a great amount of moisture without seeming wet - characteristics which all have their value in clothing. Elasticity, strength, and luster also are attributes of wool, and the kink, more or less conspicuous, aids in spinning and also in identifying the fiber. The finish given to the best grades of woolen cloth makes them stand the weather better than do other materials. There are a number of fibers commonly classed as wools which vary somewhat from sheep's wool. The more hair-like fibers from different goats and the camel do not possess the felting quality of wool, but on the other hand are more lustrous. Very attractive upholstery fabrics are made of goats' hair. Angora goat hair is manufactured into mohair as well as the various angora knitted fabrics. Camel's hair has a number of uses, and the public is more or less familiar with alpaca from the animal of that name. Wool fiber alone may be spun a second time. Loosely twisted threads, such as those in knitted fabrics or worsted goods, may be pulled to pieces and the fiber spun again either alone or in combination with new wool or cotton, the product being known as shoddy.*

* Medium priced linens for institution and home. Mary Schenck Woolman. Journal of Home Economics, 9:10:447-451.

As compared with other textile fibers, wool is light in weight in proportion to its warmth. Wool absorbs moisture very slowly. It retains drops of moisture on the outside fibers, and the lustrous surface of these fibers often causes the drops to slide off. Thus it actually sheds moisture. The durability of materials made from wool is due to the elastic nature of the fiber. Wools absorb dyestuffs readily and ordinarily retain them in their original color during the full life of the fiber. The felting, or matting, quality of wool is much increased by treating the wool with acid or alkaline solutions or even with boiling water. Such treatment softens the fiber and opens up the scales to such an extent that, when the fabric is cooled or dried, the fibers interlock more firmly than under ordinary conditions.*

* Charlotte Gibbs Baker. Seven Textile Fibers. Journal of Home Economics, 8:3:144-147.

Fig. 59. - Wool fiber, showing the characteristic scales and the serrated surface.