Page:The Strand Magazine (Volume 3).djvu/503

 glow with different and even richer tints. The cloud effects in mountain districts are brighter and more varied than in flatter regions. The morning and evening tints are seen to the greatest advantage, and clouds floating high in the heavens sometimes glitter with the most exquisite iridescent hues,

On low ground one may indeed be in the clouds, but not above them. But as we look down from mountains and see them floating far below us we almost seem as if we were looking down on earth from one of the heavenly bodies.

Not even in the Alps is there anything more beautiful than the "after glow" which lights up the snow and ice with a rosy tint for some minutes after the sun has set. Long after the lower slopes are already in the shade, the summit of Mont Blanc, for instance, is transfigured by the light of the setting sun glowing on the snow. It seems almost like the light from another world, and vanishes as suddenly and mysteriously as it comes.

As we look up from the valleys the mountain peaks seem like separate pinnacles projecting far above the general level. This, however is a very erroneous impression, and when we examine the view from the top of any of the higher mountains, or even from one of very moderate elevation, if well placed, such as, say, the well-known Piz Languard, we see that in many cases they must have once formed a dome, or even a tableland, out of which the valleys have been carved. Geologists tell us that the Alps were once, at least, twice as high as they are now, and the highest peaks are those which have suffered least from the wear and tear of time.

Geography, moreover, acquires a new interest when we once realise that mountains are no mere accidents, but that for every mountain chain, for every peak and valley, there is a cause and an explanation.

We used to speak of the everlasting hills, and are only beginning to realise the vast and many changes which our earth has undergone

The elevation of mountain chains was at first, naturally enough, attributed to direct upward pressure from below. It was supposed that forces acting from underneath raised them to their present position. To attribute them to subsidence seems almost a paradox, and yet it is not difficult to show that, in some cases at least, this is probably the real explanation. The earth, as know, has been gradually cooling, and as it contracted in doing so the strata would necessarily be thrown into folds. When an apple dries and shrivels in winter the surface, as we all know, becomes covered with ridges. Or, again, if we were to place some sheets of paper