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meteor swarms, due to gravity." Now meteorites are the only 

 tangible connection we have with " Cosmos " or infinite space ; we 

 know they are fragments, messengers if you Avill, from other worlds 

 than ours, and though few survive the rush through the earth's 

 atmosphere, yet a certain proportion reach the surface urdissolved 

 or uuvaporized, and can be submitted to chemical analysis. For 

 more than twenty years comets have been held to be clusters of 

 incandescent meteorites rendered luminous by collisions, and we all 

 know that the earth passes through two closed rings of meteors 

 every August and November, but we have now to grasp the idea 

 that infinite space is packed with meteors in unimaginable numbers, 

 flying about with immense velocity in all directions. To quote Mr. 

 liockyer : It is well known that observations of falling stars have 

 been used to determine roughly the average number of meteorites 

 which fall on the earth each 24 hours; and having this datum to 

 determine the average distance apart between the meteorites in 

 those parts of space which are traversed by the earth as a member 

 of the solar system. Dr. Schmidt, of Athens, from observations 

 made during 17 years, found that the mean hourly number of 

 luminous meteors visible on a clear moonless night by one observer 

 was 14, taking the time of observation from midnight to 1 a.m. 



' * It has been further experimentally shown that a large group 

 of obfaervers who might include the whole hemisphere in their 

 observations would see about six times as many as are visible to one 

 eye. Professor H. A. Newton and others have calculated that, 

 making all proper corrections, the number which might be visible 

 over the whole earth would be a little greater than 10,000 times 

 as many as could be seen at one place. From this we gather that 

 no less than 20 millions of luminous meteors fall upon our planet 

 daily, each of which in a dark clear night would present us with 

 the well-known phenomenon of a shooting star. 



" This number, however, by no means represents the total num- 

 ber of minute meteorites that enter our atmosphere, because many 

 entirely invisible to the naked eye are often seen in telescopes. It 

 has been suggested that the number of meteroites, if these were 

 included, would be increased at least twenty-fold ; this would give 

 us 400 millions ol meteorites falling on the earth's surface daily. 

 If we consider, however, only those visible to the naked eye, and if 

 we assume that the absolute velocity of the meteors in space is 

 equal to that of comets moving in parabolic orbits, Professor H. A. 

 Newton has shown that the average number of meteorites in the 

 space that the earth traverses is (in each volume equal to the earth) 

 about 30,000. This gives us a result in round numbers that the 

 meteorites are distributed each 250 miles away from its neigh- 

 bours. 



