WHAT IS THE CORONA i 41 1 



light of the atmosphere than ordinary atmospheric glare bears 

 to actual sunlight, a very small proportion indeed. 



But a fatal objection to the theory that the corona is due 

 either to the glare from the prominences or to light reflected 

 from the surrounding air, consisted in the fact that the so- 

 called glare ought to cover the moon's disc. 



Mr Proctor next referred to a number of observations in 

 support of the view that the coronal light is not terrestrial ; 

 such as the appearance of glare during partial eclipses, the 

 glare always trenching on the lunar disc ; the relatively greater 

 darkness of the central part of the lunar disc in annular 

 eclipses ; the visibility of that part of the lunar disc which lies 

 beyond the sun in partial eclipses, the limb being seen dark on 

 the background of the sky ; and the visibility of the corona 

 in partial eclipses; were its most distinctive peculiarities, 

 having been recognised when the sun's face is not wholly 

 covered. 

 - What, then, is the actual nature of the corona ? 



May it not consist of the denser parts of meteoric systems 

 travelling round the sun ? 



Leverrier has shown, and Mr Buxendell has helped to show, 

 that the motion of Mercury's perihelion indicates the presence 

 of a ring of bodies in the vicinity of the sun ; but we have 

 good reason for believing that for each meteor system our 

 earth encounters, there must be millions on millions whose 

 perihelia lie within the earth's orbit. Since the earth meets 

 with fifty-six such systems, it will be seen how enormous pro- 

 bably is the total number. 



