OF ARTS AND SCIENCES. 



183 



GROUP I. 



Group II., of cast bars, gave the following results. 



GROUP II. 



The bars of both groups were, subsequent to the above observations, 

 completely demagnetized, and then fre.shly magnetized. New deter- 

 minations gave the same results as before. The demagnetization was 

 accomplifihed by placing the bars inside two coils, which were traversed 

 by currents from an alternating dynamo. The coils were then slowly 

 drawn apart, and the bars maintained at a position central between 

 them. After treatment in this manner, they showed no appreciable 

 deflection when placed in position relative to the magnetometer. 



The results tabulated indicate that tungsten greatly increases the 

 magnetic moment of nickel, if the alloy be forged and rolled, but on 

 the other hand has but small influence if they be simply cast. Fur- 

 thermore, changes in the amount of tungsten do not appear to cause 

 corresponding changes in the magnetic properties. 



To see whether the remarkable effect in bars 2 and 3, as compared 

 with bar 1, of Group I. was owing to some molecular condition of their 



