EFFECT OF MAGNETIZATION ON THE PERMANENT TWIST OF NICKEL. 337 



The examination of the ab(3ve talkie shows that the first effect of 

 tAvist is always to decrease the magnetism of the wire. This decrease 

 soon ceases, and an increase sets in as the twist becomes larger. AVhen 

 the perm:ment magnetism is large, the increase is small, and the 

 oricrinal value of tlie mau'netic moment is not recovered. On theotlier 

 hand, for small values of permanent magnetism, the increase is consi- 

 deral)le; and as the twisting continues the wire acquires a greater magne- 

 tic moment than it had originally. When the wire is further twist- 

 ed, the magnetic moment reaches a maximum, and begins to decrease. 

 The maximum comes earlier for greater values of permanent magnetism. 

 The maximum increase ivi weakly magnetized wire occurs at tolerably 

 larf>'e twists, as an examinati(3n of the above tal)le will sliow. In 

 addition to this, the range of change in permanent magnetism l)y 

 twisting does not increase, but rather seems to diminish with the 

 auKHint of permanent magnetism, for moderate angles of twist. 



The experiments hitherto described show close relations between 

 the effects produced by twisting the permanently magnetized wire, and 

 those produced by magnetizing the permanently twisted wire. The 

 relation between the two can be most clearly represented by collecting 

 the results in the f)l lowing parallel statements. 



1 The permanent magnetism I. The permanent twist of nickel 

 of nickel wire is at first dimini- wire is at first diminished by 

 shed l)y twisting. magnetization. 



2. With Zan/t' ])ermanent mag- II. With swzaZ/ permanent twist, 

 netism, the decrease incre;ises with the untwisting increases with the 

 increased twist. strength of magnetizati(jn. 



3. Unless the permanent mag- III. Unless the permanent twist 

 netism is very large, tlie decrease is very small, the untwisting pro- 

 produced by twisting reaches a duced 1)y magnetization reaches a 

 maxhnum. Further twisting in- maximum. The twisting produced 



