BABBITT. — THE VON WALTENHOFEN PHENOMENON. 



251 



Discussion of the Curves. 



Throughout, the reversals consisting of more than one step fall, with 

 very few exceptions, to within 0.1 of a per cent on the 1-step curves. 

 The exceptions occur where they are to be expected, namely, where 

 there would be, with 1-step reversals only, fairly sharp changes in the 

 direction of the curves. 



A difference between the 

 first magnetization-reversal 

 curves and those that follow 

 for the same maximum of B 

 appears in each set. It is 

 most noticeable for moderate 

 values of B, from 4000 to 

 6000. In this region the 

 first two or three curves of a 

 set are of a decidedly differ- 

 ent character ; the fall in the 

 induction as represented by 

 the first seems to be charac- 

 teristic, as does the rise and 

 fall in the second and third 

 magnetizations. The curves 

 for the higher inductions 

 show the rise and fall in the 

 first curve and not a fall 

 starting immediately. For 

 any maximum of the induc- 

 tion the last curves of a set 

 take on the same general 

 shape — a sharp rise to a 

 constant maximum value. 



The point brought out earlier becomes still more prominent and con- 

 clusive. It is that a comparison of the correspondingly numbered re- 

 versals on any two successive curves cannot be relied on for definite or 

 decisive conclusions as to the effect of various processes of magnetiza- 

 tion or production of the hysteresis cycle. It may be that if one chose 

 those parts of the curves which indicated a constant value of B, the 

 comparison would be of some value ; but even here there is room for 

 doubt. 



Figure 13. Set III: B 7400: fourth 

 magnetization; O indicates 1-step reversals; 

 X 5-step reversals. 



