CHANGE OF ELASTIC CONSTANTS OF FERR0MAC4NET1CS. 



01) 



In general behaviour, the change of rigidity and its hyste- 

 resis resemble those of 45'?o Ni., except that tlie amount of the 

 change is a little less than that for this alloy. Comparing the 

 above results with those for well annealed nickel steel of the same 

 percentage, we observe that the effect of annealing remarkably 

 increases the change of rigidity. 



(a) IVIeasurement of the change of rigidity by 

 ordinary method. 



In a paper by Messrs S. Shimizu, S. Kusakabe and one of 

 us,''' the change of rigidity of ferromagnetic bars is given, having 

 been determined by first apj^lying the torsion and then the 

 magnetic field. To investigate whether the results are the same 

 or not, if the order of applying the torsion and the field, is 

 reversed, the same arrangement used in the experiment above cited 

 was availed of. The essential parts of the arrangement remained 

 unchanged, except for the mirror system. The rotating cylinder, 



to which the mirror was 



fixed, was horizontally 

 supported by means of 

 two very weak spiral 

 springs (ss) attached to 

 the sides of a carriage 

 (c) similar to that used 

 in our measurement of 

 the change of elasticity. 

 To the carriage, was 

 rigidly fixed a horizon- 

 tal axis, the conical ends 



*) K- Honda, S. Shimizu anil S. Kusakabe, \oc. cit. 



