PHOTOGRAPHS OF THE CORONA. 



Ill 



The following table gives a list of the photographs obtained 

 by members of the expeditions arranged in order of their 

 equivalent exposure ; all the photographs being reduced to the 

 standard of a camera with its focal length fifteen times that of 

 its aperture : 



Plates Nos. 1 and 2 gave no result, and Nos. 21 and 23 were 

 spoiled by the return of sunlight. 



In the above table no allowance has been made for the 

 rapidity of the plates used. 



The above photographs were handed for examination to Mr. 

 W. H. Wesley, who has most kindly prepared the diagram which 

 appears as frontispiece to this volume from the photographs, 

 and who has supplied the following report of the appearance of 

 the corona of 1898 from the photographs. 



