Elasticity of Ferromagnetic Substances by Magnetization. 



Table XXXIII. (continued). 



AX= +3-50x10°, t=16°'7 C. 



N=700xl06. 



N= 14-09 xlOc. 



= 1-2 



■'•83. 



= 25 



'f.OO 



DO. 





cK ,™ 





SK 



H. 



7 - xio j . 



H. 



7T XlO 2 . ! 







6-8 



-0-08 



151 



-019 



15-4 



-0-31 



•»..) 



-0-55 



222 



-0-57 



48-2 



-1-65 



48-5 



-160 



82-4 



-2-35 



82-4 



-2-29 



127-1 



-2-56 



127-5 



-2-38 



102-5 



-1-94 



193-2 



- 164 



288 



-067 



286 



-0-34 



398 



4-0-59 



386 



4-0-59 



508 



4-1-37 



495 



4-l-o4 



In the above tables. X is the moment of force applied in 

 C.G.S. units, and the corresponding twist of the specimen 

 as calculated from the modulus of rigidity. The change of 



rigidity obtained by our direct method is denoted by T . , 



8K 7 n 

 and that obtained by the indirect method, by -y^-. The 



8K / ... . n 



values of ==— fairlv coincide with those obtained by the 

 K H 



previous experiment ; but it is to be noticed that the field 



here given is not the effective one, but the external field 



applied. The difference between ^- and ^ — is remarkable; 



its amount is of the same order of magnitude as the change 



itself. The increase of the angle of twist slightly affects the 



change of rigidity, alwavs diminishing it in absolute amount. 



SK 

 The general feature of ^~ is quite similar to that for nickel 



wire with weak tension, as obtained by the oscillation 

 method. 



It is curious to observe that the residual twist is always 

 positive and uniformlv increases with the field, as shown 

 in PI. IV. fig. 42. ^ gK , 



It may be noticed that the course of the curve of ■==- 



SE 



K H 



closely resembles that of -^- as given by the flexure method . 



In both cases, the right order of applying the stress and the 

 field is inverted. 



