326 



On the Hall and Corbino Effects. 



that might occur during the progress of ordinary experi- 

 ments. These changes would arise, in practice, through 

 opening the magnet, changing disks, and adjusting the 

 inductance-coils. The figures below show that such changes 

 do alter the aspect o£ the readings for positive and negative 

 fields as regards their symmetry about the balance-point for 

 zero field. 



Po-P+. 



P--IV 



33 



37 



31 



37 



28 



33 



34 5 



32-5 



35-5 



36-5 



36 



34 



30 



36 



P — P + is the difference between inductance balance-points 

 for zero fields and positive fields, and P_— P is the corre- 

 sponding difference for zero and negative fields. 



These rough determinations show that, by a simple change 

 of the position of the disk in a field so distorted, the aspect 

 of the figures as regards symmetry may be totally changed. 

 This is partly taken account of by using half the difference 

 between inductance settings for positive and negative fields 

 as a measure of the Corbino effect. But this does not take 

 into consideration the symmetrical distortion of the magnetic 

 field and, as pointed out above, the experiments with the 

 solenoid are to be regarded as much the more satisfactory 

 in that regard. 



The writer is greatly indebted to Professor E. P. Adams, 

 under whose direction this research was undertaken, for his 

 generous help and unfailing interest throughout the progress 

 of the work. 



Palmer Physical Laboratory, 

 Princeton, N.J. 



