ON MAGNETOSTRICTION. 



27 



The common feature of the change is the approximate propor- 

 tionality of the effect to the magnetizing force. 



The amplitude of the change is, however, not directly proportional 

 to the intensity of magnetization, as the 46% Ni shows a smaller 

 effect than the 2i)% Ni, which is the least magnetizable among the 

 samples, with the exception of the 25% Ni, whose magnetization is 

 scarcely to be detected by ordinary means. In fields of 1600 C.Gr.S. 

 units, the change amounts to 



—^= 4.2x10-*^ for 46% Ni 



= 22.0x10-*= „ 36% Ni 



= 48.7x10-« „ 29% Ni 



= 0.2x10-« „ 25% Ni 



= 1.2 X 10"'= ,. soft iron. 



The difference between steels containing different percentages of 



