MALVACEAE 523 



in a type known as the roller gin, as the fiber is injured by the 

 saw gin type. 



When seed cotton comes to the gin, it contains boll hulls 

 and trash. This is usually removed by passing the seed 

 cotton through a cleaner, before it reaches the gin saws. 

 The boll hulls are frequently used for fuel. 



Bleaching of Cotton. — The object of this process is to 

 remove the waxy coating of the fiber, in order that it may 

 absorb the dyestufi's easily, and also remove all the impurities 

 adhering to the fiber. Cotton may be bleached in any stage 

 of its manufacture, in the loose state, as yarn, or as cloth. 

 The process of bleaching is the most thorough and is carried 

 further in the making of print cloth than in the preparation 

 of other grades of cloth, as the cloth must be absolutely white 

 and free of all impurities in order that the printing colors 

 can be applied properly, and the patterns appear distinct 

 and sharp. The cloth is first singed to remove loose fibers 

 and lint, and leave a clear even surface. It is then taken 

 through the boiling out process, in which the cloth is given 

 one or more boilings in caustic soda in order to remove the 

 waxy, fatty and pectic substances from the fiber. After a 

 thorough washing in water, the cloth is treated with a 

 bleaching powder solution. The souring process follows, 

 in which the cloth by treatment with a dilute solution of 

 sulphuric acid is rendered free of the lime compotmds and 

 undecomposed chlorine derivatives. Another thorough 

 washing then follows, after which the cloth is given a finish, 

 the nature of which depends upon the use to which it will 

 be put. 



Uses of Cotton. — The lint is spim into thread or yarn, and 

 woven into all sorts of fabrics. The finer threads are made 

 from Sea Island cotton, while ordinary threads and yarns 

 are from long staple upland cotton. The short lint or fuzz, 



