Rigidity of Ferromagnetic Substances by Magnetization. 543 



5. Steel. — We have seen that in steel the change of elas- 

 ticity due to magnetization is mnch smaller than in soft iron. 

 So, in the case of rigidity, we also observed comparatively 

 little increase. The results are given in fig. 5. We see 



Fio-. 5. 

 C5' 



fe 









(5) 



' (4-) 









i ■ * 



(3) 

 (2) 



H 























BOO 4-00 600 800 



that the form of the curves is similar to that of magnetization 

 in steel. 



Here again, the change of rigidity is independent of the 

 twisting couple for all magnetizing fields : the values of 

 SK 

 -jr- for different fields are given in the following table and 



in fis:. 4 : — 



H 



^xlO 2 . 



iv 



60. 

 0-13 



200. 

 0-22 



400. 

 0-29 



600. 

 0-32 



830. 

 0-35 



The results of previous experimenters fairly agree with 

 those of the present case. The reciprocal relation between 

 torsion and magnetization also holds for steel. 



6. Wolfram Steel. — The change of elasticity in Wolfram 

 steel due to magnetization is nearly the same as that of soft 

 iron both in quality as well as in quantity. This remark also 

 applies to the present case, so that what we have said about 

 the change of rigidity in soft iron equally applies to the case 



£00 400 600 800 H 



of Wolfram steel, as will be seen from figs. G and 4, and the 

 following table : — 



H 20. 60. 1C0. 200. 400. 600. 800. 



0-15 073 0-85 0-98 



?>* 



1-10 1-16 1-22 



