372 ANNUAL OF SCIENTIFIC DISCOVERY. 



appeared, as has been heretofore observed, to proceed directly from 

 the space situated a lit.tle below Cassiopceia's Chair, or to move in lines 

 of direction which, if continued back, would pass through that space. 

 Many of the meteors observed were followed by trains of momentary 

 duration, but none were seen of extraordinary size or brilliancy, and 

 some were mere luminous points, which, darted with excessive, ve- 

 locity. During a part of the time in which the observations were 

 made, an aurora of moderate intensity was visible. On the 10th of 

 August three observers counted 312 shooting stars between lOh. and 

 12h., and between midnight and 3 A.M., 351 different meteors were 

 noted, although many were lost by an intermission of about an hour 

 on the part of one of the observers. 



Numerous meteors were also noticed at the Cambridge Observatory 

 on the evenings of August 9th and 10th, the majority of which might 

 be traced as radiating from a point midway between Cassiopeia and 

 the pole. An aurora was also visible on the evening of the 10th. 



According to a report made by M. Angles to the French Academy, 

 great numbers of meteors were observed, on the night of the 10th, 

 near Roanne, France. From 9 p. M. until 2i A. M., the sky being clear, 

 nearly 400 were observed, although the observations did not embrace 

 one fifth of the heavens. Their general direction was northerly. 



As has been the case for some years past, the meteoric visitation of 

 Nov. 13 seems to have failed, although the weather was generally un- 

 favorable so as to prevent good observations. In fifteen minutes on 

 the morning of that day, however, only three or four meteors were 

 seen, although it was quite clear. 



METEOR OF AUGUST 19, 1847. 



M. PETIT, Director of the Observatory of Toulouse, has communi- 

 cated to the Academy of Sciences of that city a memoir on the deter- 

 mination of the orbits of meteors, not only relatively with respect to 

 the earth, but absolutely with reference to the sun. This memoir 

 contains formulae applicable to all cases where observations thoroughly 

 to be depended on are procured. The meteor of August 19, 1847, 

 afforded such observations, and in a letter published in the Astrono- 

 mische Nachrichtcn, No. 701, M. Petit states the following extraordi- 

 nary result of his calculations. The meteor, when first seen, was at a 

 distance from the earth's surface of 217,900 metres, and when last 

 in sight, of 68,900. Its relative velocity with respect to the earth 

 was 41,700 metres per second, and its absolute velocity in its orbit 

 about the sun, 70,094. At the moment of its first apparition, it was in 

 the act of describing a hyperbolic orbit about the sun, having for its 

 perihelion distance 0.9783952. and a semi-axis of 0.2385498. But 

 since at that instant it had already undergone some effect of perturba- 

 tion, both by the earth and moon, allowing for this, M. Petit con- 

 cludes, that, previous to entering the sphere of the earth's appreciable 

 action, its orbit was hyperbolic, with an eccentricity 3.95134, peri- 

 helion distance 0.95626, and semi-axis 0.32401. This meteor, there- 

 fore, must have come from the regions of space exterior to our system,, 



