1 890.] Molecular Theory of Induced Magnetism. 349 



magnets slightly, without making any of them become unstable ; the 

 second stage (6) brings the molecules into the general direction 

 shown in fig. 5 or rather that is the direction they assume when $ 



FIG. 5. 



is removed, and the residual magnetism contributed by the group is 

 then the sum of their moments resolved along . When is acting, 

 the components along are slightly greater, for the molecules 

 are then (stably) deflected through a small angle towards the line 

 of . 



Let be further increased we now have the third stage (c, 

 fig. 3), which consists in the closer approach to saturation that is 

 caused by the molecules being more nearly pulled into exact line 

 with <$ (fig. 6). Whether there will be instability during the 

 deflection of them from the lines of fig. 5 will depend on the close- 

 ness of the poles, and on the inclination of the lines of fig. 5 to the 

 direction of > (see below). In some groups, saturation will be 

 complete with a finite value of ; in others, it will only be closely 

 approximated to. In magnetising any actual specimen of iron, we 

 have, of course, to deal with a multitude of groups the lines to 

 which lie at very various inclinations to >. If we remove the 

 force at any point in stage (c), we find very little, if any, more 



