RESEMBLING THE SOLAR CORONA. 203 



Until the eclipse of 187 1 there was considerable doubt 

 how far the accounts given by observers of the corona 

 could be relied upon ; but Mr. Brothers' s photograph has 

 left no doubt on the subject. In this photograph we have 

 a lasting picture of what hitherto has only been seen by a 

 few favoured philosophers, and by them only during a 

 few moments of excitement. 



This picture shows the beautiful radial structure of the 

 corona, and the dark rifts which intersect it ; and it also 

 shows the disk of the moon, clear and free from light. I 

 have not yet seen any of the photographs of the last eclipse ; 

 but I hear there are several, and that they show the radial 

 structure and rifts even more distinctly than this one does ; 

 but whether they do or not, one photograph is positive evi- 

 dence ; the absence of more simply means nothing. 



The features to which I refer as those which distinguish 

 the solar corona are : — 



1. Its rifts and general radiating appearance. 



2. The crossing and bending of rays. 



3. Its self- luminosity, shown by the spectroscopic obser- 

 vations of Professor Young. 



4. The way in which its appearance changes and nickers. 

 When taken in connexion with the blackness of the 



moon's disk (which shows that the corona did not exist or 

 owe its existence to matter between the moon and the 

 plate on which the photograph was taken) these features 

 show that we see on the card the picture of something 

 which actually existed in the neighbourhood of the sun — 

 that the bright rays which we see photographed were 

 actually bright rays of light-giving matter, standing out 

 from the sun to an enormous distance. The rifts and 

 general irregularity of the picture show that these rays 

 do not come out uniformly all over the sun's surface, 

 but that they are partial and local, in some places thinly 

 distributed, and in others absent altogether. The rays 



