45 



magnetic poles and the intensity of the field at 

 different levels in the solar atmosphere. 



Our interest in the sun's magnetism is not con- 

 fined to the field of solar physics; its study should 

 aid in explaining the source and fluctuations of the 

 earth's magnetism and in the interpretation of 

 certain stellar phenomena. It is not improbable, 

 as Schuster has suggested, that every star, and 



m g 



SS^^Iw^^rSI^^! 



FIG. 35. Lines of Force about a Magnetized Sphere. 



perhaps every rotating body of whatever nature, 

 becomes a magnet through the fact of its rotation. 

 It is hoped that the loo-inch reflector will enable 

 this test for magnetism to be applied to certain 

 stars. 



It may be well to add that at the distance of the 

 earth the solar magnetic field can not be directly 

 appreciable, since the effect of one pole counteracts 

 the equal and opposite effect of the other pole. 



