ON COMETS. 97 



and is therefore seen for a shorter time after sunset or 

 before sunrise, as the case may be (for quite as many 

 comets are seen in the morning before sunrise as in the 

 evening after sunset). At last it approaches so near the 

 sun as to rise or set very nearly at the same time, and so 

 ceases to be seen except it should be so very bright and 

 so great a comet as to be visible in presence of the sun. 

 (6.) When this has taken place, however, the comet is 

 by no means to be considered as dead and buried. After 

 a time it reappears, having passed by the sun, or perhaps 

 before or behind it, and got so far away on the other side 

 as to rise before the sun or set after him. If it first 

 appeared after sunset in the west, it will now reappear in 

 the east before sunrise. And what is very remarkable, 

 its shape and size are usually totally different after its 

 reappearance from what they were before its disappear- 

 ance. Some, indeed, never reappear at all. The path 

 they pursue carries them into situations where they could 

 not be seen by the same spectators who saw them before. 

 Others like those which appeared in 1858 and 1861, 

 without altogether disappearing as if swallowed up by the 

 sun after attaining a certain maximum or climax of 

 splendour and size die away, and at the same time move 

 southward, and are seen, as that of 1858 was (on the 

 nth of October for the first time), in the southern hemi- 

 sphere, the faded remnants of a brighter and more glori- 

 ous existence of which we here witnessed the grandest 

 display. And on the other hand we here receive as it 

 were many comets from the southern sky, whose greatest 

 display the inhabitants of the southern parts of the earth 



