234 BELL SYSTEM TECUSICAL JOURNAL 



These effects, of course, might be produced even without a magnetic 

 field but the results of this paper indicate that conditions in the wave 

 front will l)e complicated still further by a rotation of the electric 

 vector and by the existence of bending and double refraction due to 

 the magnetic field, these effects being exaggerated in the neighbor- 

 hood of the critical frequenc\-. Due to the magnetic field we have 

 also the possibility of summation effects between components of the 

 wa\e which were split off by the action of the field and consequently 

 had traveled by different paths at different speeds. It is obviously 

 impossible to make any general statement concerning the nature of 

 the effects which will be produced by this complicated array of causes 

 but future experimental work will, we hope, allow us to estimate 

 the relative importance of the various elements. 



