746 



THE POPULAR SCIENCE MONTHLY. 



surrounded with a cloak of metallic vapors proportionately far 

 more extensive than the sun's, yet, smothered as the great star 



DRACO 



URSA MAJOR 



HERCULES 



CORONA BOREALIS 



^1926 



CANES VENATICl 



+1866 I 1 'i^ 



' 3936 



COMA 



i^n^^- 



/? 



BOOTES 



SERPENS 



VIRGO 



Map No. 11. 



seems in some respects to be, it rivals Sirius itself in the intensity 

 of its radiant energy. 



If we suppose the radiation of Arcturus to be the same per 

 unit of surface as the sun's, it follows that Arcturus exceeds the 



