120 COSxMOS. 



number of observations made in the United States of North 

 America, between the thirty-fifth and the forty-second degrees 

 of latitude, it would appear that all these meteors came from 

 the same point of space in the direction in which the Earth 

 was moving at the time. On the recurrence of falls of shoot- 

 ing stars in North America, in the month of November of the 

 years 1834 and 1837, and in the analogous falls observed at 

 Bremen in 1838, a like general parallelism of the orbits, and 

 ihe same direction of the meteors from the constellation Leo, 

 were again noticed. It has been supposed that a greater 

 parallelism was observable in the direction of periodic falls of 

 shooting stars than in those of sporadic occurrence ; and it has 

 further been remarked, that in the periodically-recurring falls 

 in the month of August, as, for instance, in the year 1839, vhe 

 meteors came principally from one point between Perseus and 

 Taurus, toward the latter of which constellations the Earth 

 was then moving. This peculiarity of the phenomenon, mani- 

 fested in the retrograde direction of the orbits in November 

 and August, should be thoroughly investigated by accurate 

 observations, in order that it may either be fully confirmed or 

 refuted. 



The heights of shooting stars, that is to say, the heights of 

 the points at which they begin and cease to be visible, vary 

 exceedingly, fluctuating between 16 and 140 miles. This 

 important result, and the enormous velocity of these problem- 

 atical asteroids, were first ascertained by Benzenberg and 

 Brandes, by simultaneous observations and determinations of 

 parallax at the extremities of a base line of 49,020 feet in 

 length.* The relative velocity of motion is from 18 to 36 

 miles in a second, and consequently equal to planetary velocity. 

 This planetary velocity,! as well as the direction of the orbits 

 ing stars was seen in North America, although the numbers were not 

 quite so considerable. (Poggend., Annalen, bd. xxxiv., s. 129.) 



On the 13th of November, 1835, a barn was set on fire by the fall of 

 a sporadic fire-ball, at Belley, in the Department de I'Ain. {Annuaire, 

 1836, p. 296.) 



In the year 1838, the stream showed itself most decidedly on the 

 night of the 13-14th of November. {Astron. Nachr., 1838, No. 372.) 



* I am well aware that, among the 62 shooting stars simultaneously 

 41 observed in Silesia, in 1823, at the suggestion of Professor Brandes 

 some appeared to have an elevation of 183 to 240, or even 400 miles. 

 (Brandes, Unterhaltungen fur Freunde der Astronomie und Physik, heft 

 L, s. 48. Instructive Narratives for the Lovers of Astronomy and Phys- 

 ics.) But Olbers considered that all determinations for elevations be- 

 yond 120 miles must be doubtful, owing to the smallness of the parallax. 



t The planetary velocity of translation, the movement in the orbit, ia 

 in Mercury 26-4, in Venus IP-^- and in the Earth 16-4 miles in a second. 



