78 Messrs. K. Honda and T. Terada on the Change of 



Soft Iron. PI. IV. figs. 43 & 44. 

 Table XXXIV. 



* = 19°-0 C. 



N =700xl0c. 



n=: 



L4-09xlO G . 



N=21-27X10 6 . 



0=:19"-65. 



0= 



=39" -56. 



0=59"-7O. 





3K' 





8K /™ 





8K' 



H. 





IT. 



K-X10». 



H. 



K^XW- 



73 



0-01 



8-4 



002 



9-3 



001 



22-0 



0-07 



22-0 



007 



22-0 



0-06 



400 



Oil 



39-6 



0-14 



39-6 



012 



733 



0-23 



733 



0-27 



72 6 



0-25 



111-3 



0-63 



1110 



0-68 



110-1) 



0-65 



160-5 



0-95 



160-5 



1-03 



160-5 



1-02 



252 



1-34 



252 



1 -42 



252 



1-43 



322 



1-51 



315 



1-58 



315 



1-60 



396 



1-66 



395 



1-73 



396 



1-75 



511 



1-79 



508 



1-87 



509 



1-87 



Since the time of the previous experiment, the specimen 

 had been once annealed at a temperature of about 1100° C, 



so that the change of rigidity ^—~ was somewhat increased 



in the present experiment. The effect of the amplitude of 

 twist on the change of rigidity is very small ; the increase of 

 the twist slightly augments the change of rigidity up to the 

 range of the twist used. The residual twist is always positive 



as in the case of nickel. T5^- is always inappreciable in the 



K XI 



greater 



present arrangement ; if it exist at all, it cannot be 



than 0*05 per cent, for the maximum field used. 



£K' 

 Thus, in nickel and iron rods, vy— is always far greater 



SK . Kn . 



than ^7 — , so that relation (3) cannot be satisfied even 



XV II 



approximately. 



In concluding the descriptions of the results of our 

 experiments, the following remarks may be added. Since we 

 measured the changes of elasticity and of rigidity for the 

 same wires of ferromagnetic metals and alloys, it will be now 

 interesting to calculate the change of Poisson ratio by 

 magnetization. As we have seen, the change of elastic con- 

 stants is considerably affected by tension, it is necessary to 



