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Their rate of motion is very slow, and slower in winter than in summer, being sometimes only a few inches, and sometimes two feet or more in the course of the day; but it never ceases entirely.

The fresh additions of snow which it is constantly receiving at its upper end, are forever pushing it on, urging it down the steep slopes and, more slowly, up the hills, and the motion is helped by the expansion and contraction of the ice with each variation of temperature, day and night, winter and summer. Every time it expands it must creep onward, be it ever so little; and when it contracts again, it cannot retreat up the slope against the enormous weight always pressing it downwards and onwards.

Then, too, it seems probable that the freezing and consequent expansion of the molecules of water, which must drain into it whenever the surface is ever so slightly melted, also help to urge the glacier onward.

The glacier's motion, like that of a river, is greatest on the surface, and greater in the middle than at the sides; and what with the strain resulting from this unequal motion, and the extremely rough, uneven character of its bed, its surface is also rough, and rent with cracks and fissures of all sizes, from a few inches to several feet

across.

Looking down upon it from a height, we should generally see on either side of the glacier a dark line, which, on closer examination, would prove to be a mound of rocky fragments, large and small, and huge blocks, many tons in weight, which have fallen from the cliffs and mountains bounding it on either side, and are thus gradually being carried down into the valley.

Thousands of tons of rock and rubbish are continually falling from the heights above; and when two glaciers meet, the two nearest "moraines," as these rubbish mounds are called, join together and form a central moraine, often twenty or thirty feet high. The three moraines then travel on together to the end of the glacier, where the ice melts and drops them, forming a “terminal moraine," perhaps eighty or a hundred feet high.

But glaciers, like rivers, are "dust makers" as well as "dust carriers"; for the joints which exist in all rocks make it easy both for running water and ice to force the blocks out of their places; and then, besides the immense heaps of rubbish which the glacier carries on its surface, large quantities also fall into its cracks and fissures, and, being jammed in between the ice and its bed, are pressed against the rocks by all the weight of the mass above.

These fragments of stone are, in fact, the glacier's tools, which it holds fast with more than a giant's grip and strength, and with which it either smooths and rounds the rocks over which it passes, or else scores them with deep grooves and ruts.

In the summer, when the glacier shrinks away from the sides of its bed, it is possible to creep in below the ice and to see both the long scratches made on the rocks and how finely these have been smoothed and polished by the sand, mud, and smaller stones, which result from the perpetual grinding of this mighty millstone.

Streams of water flow beneath every glacier, and, gushing forth at its foot, densely charged with the finest mud, form the sources of many a river; but the pebbles conveyed by a glacier stream differ from those of other streams in that they are angular.

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The glacier is not nearly such a neat workman as the river; for instead of sorting its load, dropping the larger pebbles here, the smaller there, the gravel in one place and the fine sand in another, the glacier drops its immense piles of sand, grit, stones, huge slabs, and rocks all together, and heaps them up anyhow into one great mound.

In other respects the action of the glacier is so like that of the river, that, but for the peculiar tokens of its presence in the shape of rounded, scratched, and polished rocks, there would often be some difficulty in deciding which of the two had been at work.

The perpetual grinding of the glacier millstone against the rocks, which produces the "stone meal," as it is called, naturally deepens its bed year by year: and in the course of centuries, if the supply of snow continues, it will scoop out deep channels with perpendicular cliffs.

Then, if such a change of climate should take place as has occurred many times in the earth's history, the glacier will either melt away altogether or shrink higher up among the mountains, and its former bed will become a valley with, perhaps, a glacier stream running at the bottom, and here and there some of the rounded rocks, which, from their fancied resemblance to sheep, the Swiss call "sheep rocks" (roches moutonnées).

But if the glacier terminates on the coast instead of inland, something else may happen; for if the land sinks

a thing which has often taken place then, as the glacier retreats, the sea will flow in and occupy its bed, and instead of a valley there will be a fiord. The wonderful series of fiords by which the coast of Norway is broken, and those of Patagonia, British Columbia, and Greenland, have all been thus slowly engraved by glaciers.

SPARROWS.

BY ADELINE D. T. WHITNEY.

Little birds sit on the telegraph wires,

And chitter, and flitter, and fold their wings; May be they think that, for them and their sires, Stretched always, on purpose, those wonderful strings: And, perhaps, the Thought that the world inspires, Did plan for the birds, among other things.

Little birds sit on the slender lines,

And the news of the world runs under their feet,
How value rises, and how declines,

How kings with their armies in battle meet,
And, all the while, 'mid the soundless signs,
They chirp their small gossipings, foolish, sweet.

Little things light on the lines of our lives,
Hopes, and joys, and acts of to-day,

And we think that for these the Lord contrives,
Nor catch what the hidden lightnings say.

Yet, from end to end, His meaning arrives,
And His word runs underneath, all the way.

Is life only wires and lightning, then,

Apart from that which about it clings?

Are the thoughts, and the works, and the prayers of men Only sparrows that light on God's telegraph strings, Holding a moment, and gone again?

Nay; He planned for the birds, with the larger things.

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