Smithsonian Rppnrt, 1913,~Ha 



Plate 5. 



Fig. 8.— Zeeman Doublet Photographed in Laboratory Spectrum. 



The middle .section shows the doublet. The adjacent section.s indicate the appearance 

 of the spectrum line in the absence of a magnetic field. 



Fig. 9.— n, 6, Spectra of Two Sun Spots. 



The triple line indicates a magnetic field of 4,500 

 gausses in a and of 2,900 gausse.s in b. 



