THE ECLIPSE OF 1871. 1 1 1 



coveries made during the late eclipse. It had long 

 been recognised that the solar corona appears to consist 

 of two portions distinct from each other. The inner 

 portion received (from the Astronomer-Koyal, we 

 believe) the name of the ring-formed corona, because 

 not marked by any noteworthy indentations, gaps, rifts, 

 or the like, but presenting the appearance of a some- 

 what uniform ring of whitish light around the black 

 disc of the eclipsing moon. It was to this corona that 

 some of the observers of the eclipse of December 1870, 

 mist&Renly supposing its recognition at that time to be 

 a real discovery, proposed to assign the name leuko- 

 sphere. The term was intended to indicate the 

 apparent whiteness of the inner corona. But under 

 favourable circumstances the envelope presents a 

 slightly ruddy tinge, with traces of green. 



Astronomers had begun to recognise the fact that 

 the inner ring-formed corona must be a solar appen- 

 dage, whatever may be thought of the fainter radiated 

 corona which surrounds it. The light of the ring- 

 formed corona had been examined with the spectro- 

 scope, and appears to resemble in some respects that 

 of the aurora borealis, insomuch that some astronomers 

 expressed their belief that this envelope is a perpetual 

 solar aurora. The startling nature of this conception 

 will be realised when it is mentioned that at a 

 moderate computation the ring-formed corona has a 

 depth exceeding twenty times the diameter of the 

 earth on which we live, while the actual portion of 

 space occupied by these auroral lights (if the theory 



