METEORS OP AUGUST AND NOVEMBER. TOl 



Arago/' Biot/' Quetelet,'' Olbers/" Boguslawski," Bessel/' Littrow/' and 

 others. The earliest notice on this subject in Europe v/as by Arago, in 1835, 

 after the November term of 1834. The intimation on this subject by Olmsted, 

 and its distinct announcement by Twining early in the summer of 1834, are 

 matters of record, and have one year's priority to that of Arago, for the No- 

 vember meteors, and two years' priority to a similar announcement (since so 

 happily verified) for the August period first made by Quetelet, in December, 

 1836. The last seven anniversaries of the 12th and 13th of November have 

 been carefully watched in Philadelphia by Professor Bache and others, without 

 rewarding them with the display of any unusual phenomenon, except, perhaps, 

 that of the characteristic small deflection of the convergent point already de- 

 scribed. At New Haven, and several other stations, however, an unusual 

 number, and peculiar convergent point have been noticed; and in Europe, 

 in 1836, 1837, and 1838, the extraordinary phenomenon is said to have pre- 

 sented its anniversary return. Boguslawski reports its return in 1839, in mo- 

 derate numbers. In 1840, I believe, no unusual number was seen. The de- 

 cision of the question, whether the theory of the annual periodicity of the No- 

 vember phenomenon must be considered as established by past experience, 

 depends upon the sense in which the word periodicity is employed. If by this 

 term we mean the recurrence of such remarkable and brilliant displays as 

 those of 1799 and 1833, and, perhaps, of 1832, it is clear that no return since 

 1833 has been witnessed. If, on the contrary, we restrict the term to the ap- 

 pearance of twenty or more of these bodies per hour, or twice the average 

 number, I suppose that the years 1834 — 1839, inclusive, have presented such 



*7 Annuaire, &c., 1836. *« Sill., already quoted. ^^ Catalogue, &c. 



^° Astr. Nachr. No. 372, p. 180. Olbers considers the display witnessed by Kliiver, at Bremen, 

 November 13th, 1838, as the " peculiar November phenomenon," such as occurred on the 11th, 

 in 1799, on the 12th, in 1832 and 1833, and since 1834 on the 13th, always returning somewhat 

 later. Those of the 12th November, 1838, though quite numerous, he rejects, as not moving in 

 parallel paths, nor coming from the constellation Leo, as was the case with those of the 13th. 



^^ Astr. Nachr. 391 and 412. 



'" Bessel states the number of meteors seen November 13th, 1838, at the Kdnigsberg Observa- 

 tory, at one hundred per hour. Astr. Nachr., 371. 



5^ Littrow reports the number, at same date, seen per hour at the Vienna Observatory, to be 

 one hundred and sixty-seven, see Annalen, &c., 1838, p. xvi., and ascribes the convergent point 

 to the observer's motion in space. 

 VIII. — 2 A 



