A A—Unripe Fibers; B B—Half-ripe Fibers; C C—Ripe Fibers.
Spinning Qualities
Very fine yarn can be spun from cotton because of the spiral character of the fibers. This twist of the fibers is peculiar to cotton, being present in no other animal or vegetable fiber. On account of this twist, cotton cloths are much more elastic in character than those woven from linen, the fibers of which are stiff and straight.
After the removal of the seed, no other fiber is so free from impurities—5 per cent is the loss sustained by cleaning and bleaching. In its natural condition, cotton will not dye readily because of a waxy substance on the surface of the fibers. This must be removed by washing.
Picking and Ginning
Cotton should be picked only when it is fully ripe when the pods are fully burst and the fibers expanded. The unripe fiber is glassy, does not attain its full strength and resists the dye. After picking, the cotton is sent to the ginning factory to have the seed removed. It is then pressed into bales by hydraulic presses, five hundred pounds being the standard bale in the United States.
COTTON BALES
Physical Characteristics
Purified bleached cotton is nearly pure cellulose. It resists the action of alkalis well, but is harmed by hot, strong acids, or if acid is allowed to dry on the fabric. It is not harmed by high temperature, and so may be ironed with a hot iron.