324 ff^ool in Relation to Science with Practice. 
sequently, a very important quality; for if wo take fibres which laclc this 
property, and twist them, if they possess any elasticity they will not remain 
twisted, not having any hold upon each other. Human hair will illustrate 
this. 
PIC I 
A.REI O.DZ L> 
"These structural peculiarities of wool are found to be so permanent, that 
hardly any amount of wear will in jure them ; hence it is found that woollen 
clothing reduced to the veriest ra;2;s may be torn uj) and its fibres se])arated 
into the state of wool a^ain, and then recarded and spun into yarns for the 
weaving of excellent cloths. The discovery of this fact during the present 
century has added very rnucli to our national wealth, by the prevention o{ 
waste and the creation of a new class of manufactures." 
But here I am bound to say that Youatt's " Serration as 
