Elasticity of Ferromagnetic Substances by Magnetization. 61 



one. while in the others the case is reversed. In commercial 



nickel, the increase of elasticity is the greatest ; in tungsten 



steel it is the least. In 50*72 per cent. Xi and 7CK-J2 per 



cent. Ni, the elasticity seems to attain a vague maximum at 



a high tension. ^-p 



In the calculation of -ry for different tensions, the values 

 rj 



of E for corresponding tensions were employed. This was 



absolutely necessary, since for different tensions^ E changed 



more than 10 per cent, in many of the specimens. 



(c) Comparison of the Results with those obtained 

 by the Flexure Method. 



In a previous paper by Messrs. S. Shimizu, S. Kusakabe, 

 and one of us, the change of elasticity of magnetic bars as 

 determined by the flexure method is given. It is highly 

 interesting to compare the results with those obtained by our 

 elongation method. 



In the flexure method, we observed a slight change of 

 flexure by magnetization when there was no suspended 

 weight ; this perhaps arises from the initial bending of the 

 specimen due to itso*vn weight. In subsequent experiments 

 of the kind, it was thought preferable to subtract this initial 

 change of flexure from that of flexure due to a suspended 

 load. We have therefore recalculated the former results, as 

 shown in Table XXIV. and in PI. III. figs. 26, 27. and 2S. 



Table XXIV. 





Soft 



Iron. 









Nu 



■/eel. 





1- 



500 gr. 



T = 



2540 gr. 



T= 



183 gr. 



T = 



727 gr. 



H. 



18-8 



^ X 10 2 . 



H. 



20-1 



T7 xl(R 



H. 



10-5 



fxio. 



IT. 



f XH* 



L]I 



-0-03 



+026 



-0-22 



100 



-0-19 



2(5-1 



4-U5(> 



2(i-9 



+0-55 





169 



-0-79 



16-7 



-0-72 



200 



+077 



339 



+0-76 





24-8 



-0-90 



21-9 



-0-95 



3(5 2 



4-0-89 



52-9 



+0-91 





34-5 



-1-52 



2Cr4 



-0-9S 



59-0 



4-1-01 



(59 4 



+097 





481 



— 0-53 



39-6 



-0-75 



133-4 



+ 1-04 



1290 



+ 99 





68-2 



+0-11 



68-2 



+008 



231 



-t-1-04 



212 



+1-00 









1173 



+ 1-35 



291 



+ 104 



290 



+ 1-02 





240 



+ 2-64 



2L8 



+2-57 



383 



+ 104 



398 



+ 107 





376 



496 



+301 



+ 3*29 



377 

 492 



+ 316 

 +3-25 



