THE GROWTH OF THE EARTH.

Temuka Leader, Volume I, Issue 95, 13 November 1878, Page 3

THE GROWTH OF THE EARTH.

Richard A. Proctor, in a lecture before the Society of Arts, in England, ssii-l vn speaking of meteors, that the earth is con'M;U;i!y growing by direct acereti<" : , and mast continue to do so while it remains a member of the present, ci.sinical syst ■m. This is due to the meteors of all sixes which travel in vast belts in irregular courses about the sun. These belts are numerous, and from time t.» time the earth plunges through one of them, attracting to itself the meteoric fragments and particles which come within its sphere of attraction. Not a night passes without the appearance of falling stars, and of course they continue to fall during the day, though usually unseen by human eyes. It is computed that hundreds of thousands of these extra-terrene bodies fall upon the earth every twenfy-fuur hours. The addition of a few thousand tons yearly to the earth's weight is practicably imperceptible, but it undoubtedly takes place, and in the course of millions of years, may have its effect. To this a Lowell astronomer adds : It should not be understood from the above that these " shooting stars" often reach the earth as solid matter at all. They are very small ; rarely weighing more than half a grain, according to Professor Young, and are invisible as they approach the earth until they come quite near. Before they reach the outer limit of our atmhsphere, some forty-five miles from the ground, they are doubtless cold and dark, but the friction caused by their passage through the air generates a heat which first fuses them. thus rendering them visible, and then burns them up ; that it reduces them to smoke and vapour so that whatever weight they bring is added to the atmosphere only. Once in a great while one comes along large enough to reach the ground without being consumed, and this gives us the much prized aerolite. Where the meteors come fiom is an unsettled question. Probably most scientists incline to the belief that they are fragments of cosmical matter which have been floating in space until reached by the attraction of the earth. Others' have suggested that they are the wreck of exploded planets, but the fragments resulting from such an explosion, if ever there was one, would hardly be as as small as the meteors are. With a little more probability some hoM that they are parts of the sun, hurled into space by solar volcanoes. The surface of the sun is continually being shaken by explosions of greater or less magnitude, and the explosion viewed by Professor Young a few years since undoubtedly threw matter beyond the influence of the sun's attraction ; at least such was the computation of Professor Proctor, mentioned above. Such matter must have been in the form of vapour, which would probably be widely diffused, and that it is quite possible that those who have seen aerolites have had genuine pieces of the sun within reach. The number of shooting stars is probably more rather than less than is stated by Proctor. It is not a rare thing, especially in autumn, for an observer to see one every five minutes on a clear night, and yet his field of vision does not more than one or two square miles, probably, and the meteors are of course falling just as thickly everywhere else, which would allow for the arrival of millions in a single twenty-four hours.