BABBITT. — THE VON WALTENHOFEN PHENOMENON. 



233 



Along this Hue three investigators have worked Fromme ^^ studied 

 the difference in the magnetic condition of bundles of iron wires accord- 

 ing as they were in the magnetizing solenoid when the current was 

 applied or were put in afterward. To be sure, he found a difference ; 

 but since part of his process included handling the bundles while under 

 the influence of the field it seems to me that we should not accept his 



Tsmmm 

 TPSmmssm 



CP 



III II 1 1 II hO — I 



A [^ 



nAMM^ 



RG ^ 



Figure 3. 



results as conclusive. The jarring ii and straining of the wires due to 

 the handling might account for them. Rlicker ^^ took hysteresis curves 

 consisting of various numbers of steps for a small toroid of soft iron 

 wire and observed a decrease in the maximum flux through the iron as 

 the number of steps was increased. For his specimen this decrease was 

 the most pronounced when the induction per square centimeter, B, 

 was about 4000 and amounted then to 6 per cent of the total induc- 

 tion. B. 0. Peirce ^^ compared step-by-step hysteresis curves of a 

 toroid which had a finely divided core, with similar curves calculated 

 from the manner of growth of the current in the magnetizing coil ; an 

 oscillograph supplied the necessary current-curves. Beyond the prob- 

 able errors of this method he could detect no difference between the 

 two sets of curves. 



At present, therefore, we have two diametrically opposed conclusions 

 supported by experiment. 



" Wied. Ann., 4, 76 (1878). 

 " Inaug. Diss. Halle, 1905. 



" Ibid., 5, 345 (1878). 



" These Proceedings, 43 (1907). 



