( 844 ) 
TABLE 5. 
it proceeds slowly downwards, passes, through a flat numerical 
maximum in the orange, after which the rotation decreases very 
slowly. The relation between rotation and magnetization, as in the 
cases above, exhibits distinct proportionality and we have > 530 
(Table 6, Fig. 7). 
TABLE 6. 
■&(kgs) a (mm) 
0.54 — 6.5 
3.20 
6.32 
10.37 
— 1.02' 
— 3.67' 
— 6.47' 
+ 0.03' = 0.5 „ 
± 0.05' = 0.4 „ 
± o.oar = o.i , 
± 0.93' = 0.2 „ 
± 0.03' S 0.2 „ 
It would be interesting to study the magneto-optic behaviour of 
the nearly non-magnetic nickel-iron alloy, which contains 25 percent 
nickel. 
