xx President's Address 



the Cape of Good Hope there was clear weather, and the 

 astronomers there saw the rare spectacle of a comet 

 approaching the sun, visually touching its edge, and dis- 

 appear as it passed in front of it. It has been an old wish 

 of astronomers to witness such an occurrence, with the view 

 of ascertaining the amount of opacity, if any, presented by 

 the head and nucleus of these bodies. Moreover, it had 

 been stated that in 1819 the comet was seen passing over 

 the sun's disc like a cloud, but doubts have always been 

 entertained as to the accuracy of this statement. Messrs. 

 Finlay and Elkin, assistants at the Cape Observatory, 

 watched most carefully with splendid instruments to solve 

 this question ; but although they saw the comet until it 

 seemingly touched the edge of the sun, no sign was seen of 

 it after, and it passed over the whole solar disc without a 

 trace being visible, although the observers knew its exact 

 position and could keep the wires of their telescope bisect- 

 ing the position it occupied. If there was any opaque 

 matter it was too minute to become visible with the power- 

 ful telescopes used. The comet at this part of its orbit 

 moved with immense velocity — at least sixteen times the 

 mean velocity of the earth in its orbit, or nearly 300 miles a 

 second. It passed around the sun, making the half-circuit 

 of that body in three and a half hours, with a velocity 

 almost inconceivable. Had it not been for its great velocity 

 at this portion of its orbit, when in rounding the sun it 

 swept through its coronal regions, it must have been drawn 

 into our luminary, or at least become greatly altered, both 

 in physical appearance and in the character of its orbit after 

 perihelion. That its orbit was not sensibly affected by so 

 close an approach has been shown by the calculations of 

 Dr. Kreutz, but the character of the comet underwent a 

 remarkable change after it. The nucleus round and nebu- 

 lous before perihelion became afterwards shaped like a long- 

 grain of rice, and was seen to contain first two and then 

 three bright condensations forming a triple nucleus. About 

 14th October Professor Schmidt, the astronomer at Athens, 



