EFFECT OF MAGNETIZATION ON THE PERMANENT IWIST OF NICKEL.329 



The above table shows how the iiiïtwi.stiiig' proceeds as the 

 streno^th of the field is increased. AVith the increase of the mao-netizino- 

 force, untwisting becomes greater and greater, until at a certain point, 

 the ratio of the untwisting to the corresponding magnetizing f^rce 

 reaches a maximum ; in other words, the curve of untwisting has a 

 Wendepunkt. After this, the untwisting takes place very slowly, so 

 that ultimatel}^ the curve (Fig. I, PI. XXXYIII) becomes almost 

 straight. Up to ^ = 180, the curve doesjnot reach a maximum. 



In comparing the curves obtained with different wires, we easily see 

 that the untwisting is greater for tlie thinner wire. Fc^r it will he noticed 

 in the experiments first given that the permanent twist is greater for 

 the thicker wire. Nevertheless, even with sucli liandicapping, it is tlie 

 thinner wire which has the greater untwisting as shown at a glance on 

 the curves. 



