70 



H. NAGAOKA AND K. HONDA. 



4.74 X 10"^ wLicli corresponds to a pull of 0.1 Kilog. per sq. mm. 



There is nothing remarkable in nickel. Longitudinal pull 

 produces decrease of magnetization, which becomes gradually less 

 as the field strength is increased. This is such a well established 

 experimental fact that we need not enter into further discussion 

 of the subject. 



16. Effect of Jiijdrostatic pressure. — We can easily see that 

 the change of magnetization ol due to change of volume a by 

 hydrostatic pressure is given by 



<?!=-( Z:'+-'|'-)//^ 



If we calculate the chan<>;e of mairnotization due to contrac- 

 tions 4.68 x 10"'\ 5,oö x 10", 8,42 x 10 " and t),o3 x 10 " for nickel, 

 soft iron, steel, and wolfram steel respectively, each corresponding 

 to a pressure of 10 atm., avc obtain the following values : 



