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that European giant alone, independently of the surrounding summits and of thirty-four great icy rivers or glaciers which bound that region, and which cover an area of 1,819 miles in extent, this gives only a faint idea of the vastness and sublimity of Swiss scenery.
And even the monarch of the Alps becomes small when we compare him with the wonderful height of Mount Everest, the highest of the Himalaya mountains of India, which is declared by recent measurements to be 29,002 feet above the level of the sea. But in the Himalayas the limit of snow and of vegetation is so much higher than in our mountains, that corn will grow at the elevation of 18,544 feet, which is 2,800 feet higher than the top of Mont Blanc. Yet glaciers, which were until lately supposed not to exist in the Himalaya chain, are now discovered to be numerous and large, but terminating on the north side of the mountains at about 16,000 feet above the sea level, and on the southern side at about 12,000 feet. The greater dryness of the atmosphere on the northern side of the Himalayas is the reason given for the fact that the region of ice and snow does not descend so low as on the south side.
The grandeur of such mountains is immensely enhanced by those icy rivers, which are formed and fed by their snow-clad summits, which fill their hollows and declivities, and descend by their own weight through the valleys to the plains. The best notion of a glacier may, perhaps, be gained by supposing some mighty river, a mile broad, and several hundred feet deep, pouring with vast waves down the rocky side of a mountain ; but suddenly checked in its course, and converted into ice, the gigantic waves split asunder, and projecting in sharp angles from the surface, while the whole is sparkling with dazzling brilliancy. Something of this sort filled the imagination of the poet Coleridge, when he thus addressed the glaciers of Mont Blanc
“Ye ice-falls ! ye, that from the mountain's brow
The last line alludes to the avalanche, which is another of the grand effects produced by ice and snow, and which itself assists in forming the glacier.
The vast quantity of snow which falls every winter in lower latitudes is melted by the heat of the succeeding summer; but that which falls upon high mountains, and is beyond the melting power of the solar rays, accumulates to such an extent,
that it slides off the mountain slope by its own weight, or by the action of winds and tempests, and forms “the avalanche — the thunderbolt of snow.” The snow of these upper regions is also brought down by the warmth of spring acting just below the snow line. The water formed by the melting of the snow filters through to a great depth, where it is frozen. The process goes on year after year; the snow which falls above the snow line, is not melted until it is shot down to a lower level, where in melting, and again freezing, it forms the ice of the glacier. These vast fields of ice, the result of thousands of avalanches, do not generally remain fixed in the spot where they are first formed. There are certain glaciers in the Alps which seem to have been permanent and stationary from an unknown period, but there are many others occupying the upper valleys and slopes of lofty mountains, which make a gradual, never-ceasing progress, not visible to the eye, yet always going on. Such a glacier descends with slow but resistless motion into the lower valleys—a river of ice always wasting, and always being renewed; no human power can impede or direct its progress; onward it comes, numbering perhaps not more than thirty feet in a year —until in course of time it may overturn the huts of the peasantry, and exterminate, beneath its ponderous icy foot, orchards, and fields of smiling corn. A glacier may advance in this way during a course of years, and then may be checked, or
even made to retire by a succession of severe
If we descend from the vast solitudes of snowy mountains, and of icy plains, to the habitable parts of the north, where severe frost in winter is compensated by brilliant sunshine and genial weather in summer, we again become aware of that which is grand and magnificent, and sometimes even terrible in the formation, and in the breaking up of the ice in mighty rivers.
One of the grandest and most rapid rivers in the world is the St. Lawrence, but this gigantic stream is converted, during four months of every year, into a field of rugged ice, and its freezing and thawing sometimes present phenomena of an appalling character. These were eminently displayed during the progress of that wonderful undertaking, the building of the Victoria Bridge, at Montreal, which was commenced in January, 1854, completed in December, 1859, and opened by H.R.H. the Prince of Wales, August 25th, 1860. One of the most formidable difficulties in the way of this work arose from what is called the
Shoving of the Ice,” which takes place twice a year, and is well described by Mr. Hodges in a magnificent volume presented to the Prince on that occasion, and containing a full account of the progress and the perils of the undertaking.
"Ice begins to form in the St. Lawrence," he says, “about the middle of December. Then along the shores, and in the shallow, quiet places where the current is least strong, a thin ice begins to make its appearance, gradually showing signs of increasing strength and thickness. Soon after, pieces of ice begin to come down from the lakes above; and then, as winter advances, anchor, or ground ice comes down in vast quantities, thickening the otherwise comparatively clear water of the river." He describes this ground ice as growing in rapid currents and attaching itself to rocks in the bed of the river in spongy masses, several feet deep, not unlike the spawn of frogs. A very slight thaw disengages it, and, rising to the surface, it floats along with the current. This ice grows in the neighbourhood of rapids, or where the water has become mixed with air by the rapidity of the current. It sometimes accumulates there in such quantities as to form a bar, similar to bars of sand at the mouths of rivers, and keeping back the waters several feet above their usual level. « This frequently happens at the foot of the Cedar rapids, at the head of the lake of St. Louis, where a branch of the Ottawa empties itself into the St. Lawrence. On such occasions, the water is dammed up to such a height as to change its course, and run into the Ottawa at the rate of some four or five miles an hour. From thence it eventually finds its way back into the St. Lawrence by the rapids of St. Anne's celebrated by Moore in the Canadian Boat Song'), after performing a circuit of some ten or twelve miles. The accumulation of ice continues, probably for several weeks, till the river is