2 Mr. II. E. Strickland on the Satellitary Nature 



happen to pass at the moment when the earth is crossing their 

 node, which can ever be visible to us. How then, let me ask, 

 is it brought about that these innumerable planetary bodies, 

 which are so continually entering our atmosphere and passing 

 within a few miles of the earth, never come in contact with it? 

 for be it remembered that aerolites are not regarded as being 

 the shooting stars themselves, but only as fragments left be- 

 hind them in their course. Can we suppose that our earth, 

 a body of nearly 8000 miles diameter, should be incessantly 

 forcing its way through showers of these planetary bodies, 

 hundreds of which daily approach in their circumsolar revo- 

 lutions within from 16 to 140 miles of the earth, and yet that 

 they should never impinge upon its surface? Should we not 

 in that case continually hear of these fiery masses, with dia- 

 meters from 80 to 2600 feet, and velocities of 36 miles a se- 

 cond, dashing into the body of our earth like cannon-balls 

 into an earthen rampart? If, in order to meet this objection, 

 it be asserted that the real diameter of the shooting stars has 

 been over-estimated, and that aerolites are not fragments of, 

 but are identical with these bodies themselves, which accord- 

 ingly really do fall upon the earth's surface, still on the doc- 

 trine of chances it would follow that the earth's disc, which 

 presents a far larger surface than that portion of its atmo- 

 sphere which surrounds and projects beyond its limb, must 

 receive a proportionally larger number of these projectiles. 



The attraction of the earth would still further increase the 

 amount of those asteroids which would come in contact with 

 it, as compared with those which pass through and escape 

 from the atmosphevic stratum ; yet, what is the real propor- 

 tion between the two classes of phaenomena? We find in 

 reality that shooting stars, that is, asteroids rendered visible 

 by atmospheric contact, occur to the amount of scores, some- 

 times of hundreds, every night, while the fall of aerolites upon 

 the earth's surface is a phaenomenon of very much rarer oc- 

 currence. It seems evident therefore that there is some cause 

 which renders the circulation of asteroids in orbits approxi- 

 mately parallel to the earth's surface, the normal condition, 

 to which the fall of aerolites to the ground (whether we regard 

 them as being the entire nuclei, or merely detached fragments 

 of these meteors) forms only a casual exception. 



To what then must we attribute this constant flight of aste- 

 roids in lines closely approximating, yet not impinging upon, 

 the earth's surface? It seems evident that we cannot regard 

 them as solar planets, pursuing their course through the sy- 

 stem regardless of intervening obstacles, as they must inevi- 

 tably in that case come into very frequent contact with our 



