126 COSMOS. 



25tli of April, between the Gth and 12th of December-, and, 

 to judge by the number of true falls of aerolites enumerated 

 by Capocci, also between the 27th and 29th of November, or 

 about the 1 7th of July. 



Although the phenomena hitherto observed appear to have 

 been independent of the distance from the pole, the tempera- 

 ture of the air, and other climatic relations, there is, however, 

 one perhaps accidentally coincident phenomenon which must 

 not be wholly disregarded. The Northern Light, the Aurora 

 Borealis, was unusually brilliant on the occurrence of the 

 splendid fall of meteors of the 12th and 13th November, 1833, 

 described by Olmsted. It was also observed at Bremen in 

 1838, where the periodic meteoric fall was, however, less re- 

 markable than at Richmond, near London. I have mentioned 

 in another work the singular fact observed by Admiral Wran- 

 gel, and frequently confirmed to me by himself,*' that when he 



probably the enormous fall of aSrolites that occurred at the Rio Assu, 

 near the village of Macao, in the !6razils, on the 11th of December, 1836. 

 (Brandes, Unterhalt. fur Freunde der Physik, 1825, heft i., s. 65, and 

 Comptes Rendus, t. v., p. 211.) Capocci, in the interval betvreen 1809 

 and 1839, a space of thirty years, has discovered twelve authenticated 

 cases of aerolites occurring betw^een the 27th and 29th of November, 

 besides others on the 13th of November, the 10th of August, and the 

 17th of July. (Comptes Rendus, t. xi., p. 357.) It is singular that in 

 the portion of the Earth's path corresponding vv^ith the months of Jan- 

 uary and February, and probably also with March, no periodic streams 

 of falling stars or aerolites have as yet been noticed ; although, when 

 in the South Sea in the year 1803, I observed on the 15th of March a 

 remarkably large number of falling stars, and they were seen to fall as 

 in a swarm in the city of Quito, shortly before the terrible earthquake 

 of Riobamba on the 4th of Februaiy, 1797. From the phenomena hith- 

 erto observed, the following epochs seem especially worthy of remark : 



22d to the 25th of April. 



17th of July (17th to the 26th of July ?). (Quet., Corr., 1837, p. 435.) 



10th of August. 



12th to the 14th of November. 



27th to the 29th of November. 



6th to the 12th of December. 



When we consider that the regions of space must be occupied by 

 myriads of comets, we are led by analogy, notwithstanding the differ- 

 ences existing between isolated comets and rings filled w^ith asteroids, 

 to regard the frequency of these meteoric streams with less astonish- 

 ment than the first consideration of the phenomenon would be likely 

 to excite. 



* Ferd. v. Wrangle, Reise Idngs der Nordkuste von Sibirien in den 

 Jahren, 1820-1824, th. ii., s. 259. Regarding the recurrence of the 

 denser swarm of the November stream after an interval of thirty-three 

 years, see Olbers, in Jahrb., 1837, s. 280. I was infonmed in Cumana 

 that shortly before the fearful earthquake of 1766, and consequently 

 thirty-three years (the same interval) before the great fall of stars on 



