124 ON COMETS. 



tail, which stretched half-way across the sky after sunset 

 in March of that year. But its head, as we here saw it, 

 was not worthy such a tail. Farther south, however, it 

 was seen in great splendour. I possess a picture by Mr 

 Piazzi Smythe, Astronomer-Royal of Edinburgh, of its 

 appearance at the Cape of Good Hope, which represents 

 it with an immensely long, brilliant, but very slender and 

 forked tail. Of all the comets on record, that approached 

 nearest the sun indeed, it was at first supposed that it 

 had actually grazed the sun's surface, but it proved to 

 have just missed by an interval of not more than 80,000 

 miles about a third of the distance of the moon from 

 tlie earth, which (in such a matter) is a very close shave 

 indeed to get clear off. There seems very considerable 

 reason to believe that this comet has figured as a great 

 comet on many occasions in history, and especially in 

 the year 1668, when just such a comet, with the same 

 remarkable peculiarity, of a comparatively feeble head 

 and an immense train, was seen at the same season of 

 the year, and in the very same situation among the stars. 

 Thirty-five years has been assigned with considerable 

 probability as its period of return, but it cannot be re- 

 garded as quite certain. (It will of course be understood 

 that the return of a great comet to the neighbourhood of 

 the sun by no means implies that it should be a con- 

 spicuous one, as seen from the earth. The phase of its 

 greatest development may be, and is, indeed, more likely 

 than not to be, ill-timed, as regards the relative situations 

 of the earth and sun, for its exhibition as a great celes- 

 tial phaenomenon.) 



