All the complex processes and machinery of the textile industry are but developments of the old-time methods of the home. Brief outlines only will be given here for the processes are most intricate in detail.
The spinning of cotton yarn (thread) is typical of all the fibers. The stages may be divided into--
1. Opening and picking. 2. Carding. 3. Combing. 4. Drawing. 5. Spinning.
The picking and carding have for their object the removal of all foreign substances with as little damage to the fiber as possible. The foreign substances in cotton are sand, dirt, pieces of leaves, seed, husk, etc., which have become mixed with the fiber during the process of growing, ginning and transportation.
The cotton bales are opened and thrown into the automatic feeder which carries up a layer of cotton on a spiked apron from which it is removed by a rapidly revolving "doffer" underneath which is a screen which catches some of the dirt. It is next fed between rolls in front of a rapidly revolving blunt-edged knife which throws out more of the dirt through a screen. There is a suction of air through the screen which helps remove the foreign substances. The cotton passes through several of such machines, being formed into a soft web or "lap" which is wound into a roll.
The carding machine further cleans the fibers and lays them in a general parallel position. From this machine the web is formed into "sliver," a loose rope of cotton fiber about two inches in diameter. This is received in circular cans.
The cotton from the bale is thrown into _A_, carried by the spiked aprons _B_ and _C_, evened by _E_, removed from the apron by _F_ (some of the dirt falls through the screen into box _G_) is beaten by the revolving "knife," _N P_, more dirt being removed through screen _N_, then goes through the flue _C_ to the next machine.]
The combing is omitted for short fiber cotton, but is used in worsted spinning and with long staple cotton to remove the short fibers. Cotton to be used for making yarn suitable for hosiery, underwear, sewing thread, lace, and for very fine cotton fabrics is carded.
In drawing, from six to sixteen "slivers" are run together and the fibers drawn out in several stages until the soft rope is about an eighth of an inch in diameter, called "roving." This tends to get rid of any unevenness and makes the fibers all parallel. From this machine the roving is wound on a bobbin ready for the spinning frame.