THE 



POPULAR SCIENCE 

 MONTHLY. 



AUGUST, 1872. 



THE AUGUST AND NOVEMBER METEORS. 



By Db. H. SCHELLEN. 



WHOEVER has observed the heavens on a clear night with some 

 amount of attention and patience, cannot fail to have noticed the 

 phenomenon of a falling star, one of those well-known fiery meteors 

 which suddenly blaze forth in any quarter of the heavens, descend 

 toward the earth, generally with great rapidity, in either a vertical or 

 slanting direction, and disappear after a few seconds at a higher or 

 lower altitude. As a rule, falling stars can only be seen of an evening, 

 or at night, owing to the great brightness of daylight ; but many 

 instances have occurred in which their brilliancy has been so great as 

 to render them visible in the daytime, as well when the sky was over- 

 cast as when it was perfectly cloudless. It has been calculated that 

 the average number of these meteors passing through the earth's atmos- 

 phere, and sufficiently bright to be seen at night with the naked eye, 

 is not less than 7,500,000 during the space of twenty-four hours, and 

 this number must be increased to 400,000,000 if those be included which 

 a telescope would reveal. In many nights, however, the number of 

 these meteors is so great that they pass over the heavens like flakes of 

 snow, and for several hours are too numerous to be counted. Early in 

 the morning of the 12th of November, 1799, Humboldt and Bonpland 

 saw before sunrise, when on the coast of Mexico, thousands of me- 

 teors during the space of four hours, most of which left a track behind 

 them of from 5 to 10 in length ; they mostly disappeared without any 

 display of sparks, but some seemed to burst, and others, again, had a 

 nucleus as bright as Jupiter, which emitted sparks. On the 12th of 

 November, 1833, there fell another shower of meteors, in which, ac- 

 cording to Arago's estimation, 240,000 passed over the heavens, as 

 seen from the place of observation, in three hours. 



Only in very rare instances do these fiery substances fall upon the 

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