CHANGE OF VOLUM r: AXD OF LENGTH. 65 



' -Wendepunkt '; after tliat the change becomes slower, but still goes 

 on increasing nearly in a straight line. Up to H=2000, the 

 rate of change shows no tendency to decrease. Witli a still 

 stronger held, the increase of volume will prol)al)ly become 

 more considerable. 



12. In our former experiment, the range of the magnetizing 

 force was confined to a few hundred C. G. S. units. In the present 

 experiment, the increased field strength unveiled the character of 

 the change of the volume considered as function of the intensitv 

 of magnetization. As will be seen from the curves (Fig. 2.) in 

 dotted lines, the increase in nickel and steel takes place quite 

 slowly befoi'e the magnetization reaches saturation. As soon as 

 the magnetization reaches this state, the increase becomes very 

 rapid, so that the branch of the curve ascends nearly parallel to 

 the axis of volume increase. There we find that a sliolit increase 

 in magnetization is attended with a laige increase of volume. 

 As the rate of increase appears to be nearly constant, it would be 

 very interesting, if we could push the field strength still farther to 

 see whether the volume change ultimately attains an asymptotic 

 value. 



The observed changes of volume and of length are exhibited 

 in the followins: table : — 



]) Cantone, Atti della R. Accad. dei Lincei, 6, (1), 257, 1891. 



