WOOL. 



211 



of wool is often carried out by hat manufacturers, who find the burs in 

 the wool difficult to deal with. When the vegetable burs and impurities 

 have been carbonised in the stages of hat body-making, the carbonising 

 serves a very useful purpose. 



Carbonising is employed in the treatment of rags composed of mixed 

 woollen materials, such as stuff goods with a cotton warp and woollen 

 weft, or a mohair weft with cotton warp. Carbonising in this case 

 destroys the vegetable fibres of the yarn, while the animal fibres are 

 preserved and afterwards used in the manufacture of some other kinds 

 of low-class goods. The fibres of wool that have been extracted from 

 mixed goods are known in the trade as " Extract Wool." 



Fig. 137. Worsted yarn (magn. ). 



Worsted Yarns. Fig. 137 represents the warp and weft yarns of a 

 worsted fabric. The principle of construction in these two yarns is 

 nearly the same. They are built on the same principle as combed cotton 

 yams ; the shorter fibres have been eliminated, and the longer woollen 

 fibres lie in close contiguity together. The thinner yarn is the twist 

 warp, and the thicker one is the soft covering weft in which the wavi- 

 ness is well marked, and contrasts with that of the lighter spun warp 

 thread. 



Worsteds. In Bradford combed worsted yarns the drawing and re- 

 drawing of the threads is carried to a high pitch of perfection. As an 

 instance of the care and attention bestowed upon it, a quotation may be 

 made from Mr. Charles Vickerman's Woollen Spinning as follows : " Take 



