OF FERROMAGNETIC WIRES BY MAGNETIZATION. 



11 



\Yith the other annealed nickel steel {?>b% Ni), whose thickness 

 is 1.50 mm., the njiture of the ma2:netic elong-ation and the eitect of 

 tension are generally the same as those of the former alloy, as sh(^wn 

 in Fig. 11. The course of the curve for heavy loading is, however, 

 quite difl'erent from that for light loading. For a tension of 4.76 

 kilograms per square millimeter, the wire first contracts and then 

 elongates when the field is gradually increased, so that the form of the 

 curve is similar to that of the maofnetic chano^e of leng^th in cobalt. 

 Fig. 12 shows that the rate of diminution of the magnetic elongation 

 b}' tension decreases as the tension is increased. 



The curves corresponding to T=^0 in Figs. 8 and 11 are the 

 results obtained by Professor Nagaoka and one of us, and are 

 reproduced here for the sake of comparison. 



The following table contains some of the results of our measure- 

 ments : — 



