CHANGE OF ELASTIC' CONSTANTS OF FERROMAGNETICS. 



r)7 



In general features, the change of rigidity is similar to that 

 of the former alloy, but the rate of increase is less for the present 

 alloy than for the former. Under slight tension, we observe, in 

 the alloy, a slight decrease of rigidity in very weak fields. Such 

 an initial decrease is not observable in the former alloy. This 

 decrease of rigidity, however, diminishes with increasing tension, 

 vanishing with a tension of 3895 gr./mm.^ 



One of the two hysteresis-curves (Fig. 60) refers to the first 

 cycle, while the other (Fig. 61) to a cycle after several cyclic 

 changes of field. The form of the curve closely resembles the 

 inverted form of the hysteresis curve of the magnetic change of 

 length in iron, as discovered by Professor Nagaoka. 



