METEORIC STONES AND SHOOTING STARS. 



1. PROFESSOR ENCKE made a computation founded on the whole 

 collection of observations made on the meteors which appeared 

 in November, 1833, in the United States, over an extent of 

 country included between the latitudes 35 and 42, from which 

 he inferred that all these meteoric bodies had a common 

 direction, and that their motion was exactly contrary to that 

 which the earth had at the moment of their appearance. In 

 the great showers of shooting-stars which were afterwards 

 observed in November, 1834, 1837, and 1838, the same general 

 parallelism of the directions of their motion was ascertained, 

 and as before, they were observed to move from a certain point 

 in the constellation of Leo. 



A similar parallelism of direction has been observed in the 

 showers of shooting-stars which appear at other times of the 

 year, and it is ascertained that those which reappear in the 

 same month have always the same direction. 



On the 13th November, 1834, a like shower of shooting-stars 

 was witnessed in North America, but much less considerable in 

 point of numbers. 



On the 13th November, 1835, a meteorite fell in France in the 

 department De FAin, which set fire to a barn. 



On the same night a shooting-star, larger and brighter than 

 Jupiter, was seen at Lille. It left behind it a train of sparks 

 like those which issue from a rocket. 



2. Whatever be the origin of the phenomena of shooting-stars 

 it cannot fail to be interesting to learn the principal circum- 

 stances which observation has collected respecting them. 



Their apparent magnitudes are very various. Sometimes 

 they are not brighter or larger than the smallest star visible to 

 the naked eye, and at other times they surpass in splendour the 

 most brilliant of the planets. Sometimes the globular form can 

 be distinctly recognised upon them, and they are not distin- 

 guishable from the meteors called fire-balls. 



3. Shooting-stars seem to prevail equally in every climate 

 and in every state of the weather. They are occasionally seen 

 at all seasons of the year, but more frequently in summer or at 

 the end of the autumn. They appear usually to be followed by 

 a luminous train of intensely white light. 



A question will immediately arise, whether this be a real 

 continued physical line of light, or whether it must not rather 

 be ascribed to the same cause which makes us see a complete 

 circle of light when a lighted stick revolves rapidly in a circle 

 In that case the circle of light is not real, the effect being an 

 optical illusion. The membrane of the eye which is affected by 

 light has been ascertained to preserve the impression made upon 

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