204 



H. XAOIAOKA. 



essential change. If the twist be still more increased, two eases are 

 quite possible; either the going and the returning branches of the 

 curve Avili continually tend to approach, or the going will ultimately 

 lie below the returning branch, so that reversal of hysteresis ^vill 

 declare itself. 



Reversal of hysteresis. — To solve this question, a wire 27 ems. long 

 and 0.6b' mm. "thick was treated in the usual way, and twisted through 

 ± 360°. The twist thus applied was very large ami amounted io 

 13°"3- per cm. After a number of twistings and untwisting«, the fol- 

 lowing reading's of deflections were taken for ti = 2A). 



