on the Night of Nov, 13. 1833. 387 



days after, in a directly contrary direction ? It is certainly pos- 

 sible, and more than probable, that both occurrences had one 

 origin; but, on Professor Olmsted's arguments, they could 

 not, without involving difficulties of a serious nature. Surely 

 he would not contend that the meteors seen by Sir W. Ha- 

 milton in the electrical display on Vesuvius (VII. 301.) 

 were otherwise than volcanic : — yet, why do we not call them 

 cometic f 



The whole argument of the professor rests on the general 

 assumption that these displays of falling meteors are different 

 from all others which have been denominated, and even by 

 him, aerolites : now, evidence undoubtedly goes to establish 

 their similarity. The singularity of these occurrences being 

 so commonly about a particular day in November had pre- 

 viously struck me, and certainly lends an air of probability to 

 the professor's supposition. But periodicity is not, surely, 

 confined to extra-terrestrial bodies. I shall, perhaps, have 

 an opportunity of showing, in some future portion of my 

 observations on the earth's derangements, that those disturb- 

 ances obey a periodical law, and that, consequently, all their 

 results obey the same impression. Professor Olmsted asserts 

 that it is his belief that what has commonly been designated 

 as the zodiacal light is identical with the light from his meteoric 

 comet ; and that the frequent displays of that light, recently, 

 so correspond with the assigned position of the comet as to 

 involve the identity of both. On this point I shall be silent ; 

 farther observation, and the eyes of astronomers, will be the 

 best means of elucidating it. 



After having made these remarks, it is incumbent upon me 

 to offer a few words in defence of my own previous attempt 

 to explain the connection of the meteors with my subject. In 

 order to bring the topic within my reach, I must quote from 

 Professor Olmsted himself, who remarks that the meteors were 

 directed to the earth in a shower from a cloud, which must 

 have remained stationary a long time at a great height above 

 the earth (p. 142.) : he calculates, above 2238 miles, (p. 144.) 

 I have always been of opinion, in which many persons will 

 agree (see Mr. Lees, in The Analyst^ No. i. p. 36.), that phi- 

 losophers are too apt to talk of hundreds and thousands, 

 when, perhaps, units and tens would be nearer the mark. I 

 allude expressly to the frequent mention of bodies entering 

 the earth's atmosphere from tremendous heights. Is it actu- 

 ally known what is the real height of the earth's atmosphere ? 

 and can any one define it ? It appears to me more probable 

 that space is filled with atmosphere, denser, doubtless, towards 

 all bodies moving therein ; and that it is not philosophical to 



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