4 Mr. W. N. Bond on the Properties of 



measured, this is equivalent, approximately, to constant 

 stress at any one point. 



Fig. 4 shows the result of an experiment in which the- 

 load was changed for an equal one acting in the opposite 

 direction, after a certain amount of bending had taken place. 

 Finally the crystal was loaded as at the start. 



Fiji'. 4. 



fc. 



id 



TTi 



Length 1= 25 omA 

 Defth d= .2*o«3 

 Breadth b s '24 c/wj 

 Loid m= SOgra-KS. 



50 Hours. 



Fig. 5 shows the effect of varying the sense and the mag- 

 nitude of the load on another crystal clamped, as before, at 

 one end. We see that for small stresses the deflexion 

 tends to a limiting value. The rate of bending is not 



