Page:Popular Science Monthly Volume 64.djvu/355

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PEAKING broadly, we know as yet of no fundamental reason why meteorite falls should be any more numerous upon one part of the earth's surface than upon another.

Compared with the vast area of space in which meteorites wander, our earth is but a point, which draws into itself from time to time one of these masses. Moreover, it is a rotating and wabbling point, ever presenting new surfaces to the portions of space in which it is traveling. The marksman who displays his skill by shooting glass balls thrown into the air would have the difficulty of his task enormously increased if he should endeavor to strike successively the same point upon the ball, especially if it had in addition to its forward motion one of rapid rotation about a wabbling axis. It is true that there is some prospect of our being able after much study and comparison of data to locate a few meteorite swarms with sufficient accuracy to warrant a conclusion as to what point upon the earth stones from them will strike, but this possibility seems at present quite remote. At present we can only presume that a gentle rain of meteorites has fallen regularly and impartially upon the earth since the morning stars first sang together.

The latest and best calculations, which are by Professor Berwerth, of Vienna, have shown that the number of meteorites actually falling upon the earth at the present time each year, not including of course shooting stars or meteors, is about nine hundred. Two or three of these bodies fall, then, somewhere upon the earth every twenty-four hours. But about three fourths of the earth's surface is covered with water, and the missiles impinging upon this area are lost. Upon the remaining one fourth, however, 225 falls should take place, accompanied by phenomena such as to make the occurrence noteworthy, A large part of the land is, however, unpopulated and our figure of 225 may, therefore, be cut in half in order to take account of this factor. Again, falls taking place in the night would, in many cases, not be observed, and as a last concession we may halve our figure on this account. It would finally seem then that about 55 meteorite falls capable of record might be expected to take place each year, and in a century the total should be 5,500. As a matter of fact, the total number of recorded meteorite falls, including some from as far back as the fifteenth century, is only about 350.