CHAPTER VIII 

 MOISTURE IN WOOL 



Testing wool or tops for moisture Amount of moisture permissible in 



wool and tops. 



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WOOL is the most hygroscopic of all textile fibres that is, its power 

 to retain moisture is greater than any other textile fibre. The 

 normal amount of moisture in wool is 16 per cent., and if a sample 

 contains, say, 20 per cent, of moisture, it will lose 4 per cent, of its 

 weight if kept for any length of time in a normal temperature. 

 Greasy wool will not absorb so much water as scoured wool or 

 tops. Buyers can therefore detect moisture in greasy wool much 

 more easily than they can when it is in the scoured state. The 

 reason for this is, that all the grease or yolk is removed from the 

 scoured wool, and the moisture gains free access to the fibre and 

 lodges in its interstices and cells, whereas in the greasy state it 

 is much more difficult for the moisture to obtain access to the fibre 

 because it is surrounded by a thin coating of yolk. Consequently, 

 the moisture is more easily detected, being mostly confined to the 

 outside of the fibre. All wool that is shorn damp will lose weight 

 if kept for any length of time, till the moisture it contains does not 

 exceed 16 per cent. Sometimes, in the back-country, where the 

 wool is shorn in excessively hot weather, the moisture it contains 

 may.be below the 16 per cent. In this case the wool will gain 

 weight when kept for a short time in a normal temperature. In 

 Bradford the wool merchants have fixed a standard amount of 

 moisture in the various classes of raw and partially manufactured 

 wool. These standards were obtained by testing for several months 



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