BABBITT. — THE VON WALTENHOFEN PHENOMENON. 



245 



process would not affect the iioii- magnetic condition. This is the 

 initial condition for the next magnetization and, if not twice the same, 

 might well be the cause of the variations observed in the early part 

 of the magnetization-reversal curves. It seems to be the more prob- 

 able cause, inasmuch as the previous magnetizations were pretty nearly 

 alike and would be expected to give less haphazard variations thaa 

 •were actually observed. If 

 the demagnetizing process 

 for any given maximum of 

 B, or at any rate that part 

 of it which affected appre- 

 ciably the non-magnetic 

 condition of the iron, were 

 carried out always in the 

 same manner, I am in- 

 clined to believe that in 

 most cases the sixth or 

 seventh magnetization- 

 reversal curves would be 

 duplicated by those that 

 followed. However, it 

 seems to be impossible to 

 obtain a second time the 

 magnetic condition exhib- 

 ited, for a given maximum 

 of B, by any point of the 

 first few curves. The same 

 value of B might be ob- 

 tained, but that does not 

 mean the same magnetic 

 condition ; for the next 

 reversal in the two cases 

 would yield distinctly different values of B. 



The tedious process of making each demagnetization the same was 

 not suited to the apparatus at hand and would require a large amount 

 of time and trouble. Furthermore, the relative effect of the various 

 parts of the demagnetizing process on the non-magnetic condition is 

 practically unknown. These two facts eliminated for the present a 

 continuation of the work by the comparison of any two curves separated 

 by a process of demagnetization. Even such knowledge as I have indi- 

 cated would be of no avail for the first few curves of a set, where it is 

 probably impossible to duplicate any point of the magnetic condition. 



Figure 7. Set II: B 6000: sixth magneti- 

 zation; O indicates 1-step reversals; X 3-step 

 reversals. 



