62 



Journal of Agricultural Research voi. xix. No. a 



40 to 80 per cent, although the curve makes almost a straight line from 

 70 per cent up to the point of saturation. The elasticity curves for 

 scoured and unscoured wool are nearly parallel, rising as the humidity 

 changes from 40 to 80 per cent and falling from this point to that of 



saturation. 



SUMMARY 



(i) The tensile strength of wool increases with the decrease in the 

 diameter of the wool fiber. 



(2) Fine wool has a breaking strength varying more closely with the 

 first than with the second power of the diameter. 



4-4 



42 



\40 



34 



"32 

 \30 



\2e 



%-^ 



24 



40 s5o SO yo <9o s^mem^ 



Fig. 4.— Graphs showing the effect of humidity upon the breaking strength and elasticity of wool fiber. 



(3) Coarse wool has a breaking strength varying with a figure which 

 lies somewhere between the first and second powers of the diameter. 



(4) It is necessary to mix samples of fine wool carefully before testing 

 in a testing machine if the best results are to be obtained. 



(5) The breaking strength and tensile strength of both scoured and 

 unscoured wool decrease with an increase in relative humidity from 40 

 to 80 per cent and show a tendency to increase from this point to that of 

 saturation. 



(6) The elasticity of scoured and unscoured wool increases with an 

 increase in relative humidity from 40 to 80 per cent and decreases from 

 this point to that of saturation. 



