METEORS OF AUGUST AND NOVEMBER. 121 



phenomenon again in all its splendour, as in 1799 and 1833. In the interval, 

 however, it is of the highest importance that philosophers of every country 

 should give the most careful attention, on the well known days of November, 

 to the current appearances of these periodical shooting stars, as they are pro- 

 perly called in contradistinction from those sporadic meteors which occur 

 throughout the year." 



The objections of Dr. Olbers to the theory of the zodiacal light as the origin 

 of the November meteors, ascribed to Biot, but, in fact, first proposed by Pro- 

 fessor Olmsted, and still I believe maintained, are stated in the 281st and 282d 

 pages of the same work. Dr. Olbers pronounces it impossible to explain the 

 motions of the November meteors, whose relative velocity he states at from 

 sixteen to twenty geographical miles per second, by the supposition of a direct 

 orbit round the sun, such as theory ascribes to the zodiacal light. Moreover, 

 the nodes of the sun's equator are not in the 20th degree of Taurus, but in the 

 20° of Gemini. 



I may here remark, in confirmation of Olbers' statement, that the data of 

 Tables I. and III., as presented in Table VI., give to the November meteors 

 an orbit inclined 121°. 1 to the ecliptic, in other words retrograde. 



The opinion of the younger Littrow,'^ based upon a year's observations of 

 these bodies, is as follows : — " Shooting stars are most probably of cosmical 

 origin, as is shown by their return at stated periods of the year, and at parti- 

 cular portions of the heavens, both of which seem to depend upon the motion 

 of the earth." 



" The dates of the 10th of August and 12th of November are properly con- 

 sidered as periods when a richer fall of shooting stars may be expected." 



" The phenomena of these two dates are different from those of ordinary 

 nights. While the former exhibit a certain regularity in the place of their ap- 

 pearance and their directions, the latter seem to wander without rule in all 

 parts of the heavens." 



" The shooting stars of August and November are also of a different nature, 

 in as much as they appear in quite opposite parts of the heavens, and the 

 former are seen going towards that part of the celestial sphere from which the 



^^ Annalen, &c., for 1838, p. xviii. 

 VIII. — 2 F 



