H. E. J. G. Dü BOIS and G. J. ELIAS. The influence of temperature and 

 magnetisation on selective absorption spectra. 



■^—^ violet 



red 



1. Ruby bands in the solar spectrum. 



2. Ruby bands outside the field at 18-^. 



3. Ruby bands in the field at 18^, 



Proceedings Royal Acad. Amsterdam Vol. X. 



