Ragnarok : the age of fire and gravel

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WAS IT CAUSED BY GLACIERS? be?

CHAPTER V. WAS IT CAUSED BY GLACIERS?

Wnuat is a glacier? It is a river of ice, crowded by the weight of mountain-ice down into some valley, along which it descends by a slow, almost imperceptible motion, due to a power of the ice, under the force of gravity, to rearrange its molecules. It is fed by the mountains and melted by the sun.

The glaciers are lecal in character, and comparatively few in number ; they are confined to valleys having some general slope downward. The whole Alpine mass does not move down upon the plain. The movement downward is limited to these glacier-rivers.

The glacier complies with some of the conditions of the problem. We can suppose it capable of taking in its giant paw a mass of rock, and using it as a graver to carve deep grooves in the rock below it ; and we can see in it a great agency for breaking up rocks and carrying the detritus down upon the plains. But here the resemblance ends,

That high authority upon this subject, James Geikie, Says:

“ But we can not fail to remark that, although scratched and polished stones occur not infrequently in the frontal moraines of Alpine glaciers, yet at the same time these moraines do not at all resemble till. The moraine consists for the most part of a confused heap of rough angu-

dur stones and blocks, and loose sand and débris ; scratched 2