Aletsch Glacier

“ The Aletsch glacier, in the Alps, is fifteen miles long, and some are even longer than this. They move very slowly - on an average about 20 to 27 inches in the centre, and 13 to 19 inches at the sides every twenty-four hours, in the summer and autumn. How they move, we cannot stop to discuss now; but if you will take a slab of thin ice and rest it upon its two ends only, you can prove to yourself that ice does bend, for in a few hours you will find that its own weight has drawn it down in the centre, so as to form a curve. ”

“ Ales′si, Galeazzo, a distinguished Italian architect, born at Perugia, 1512, died there in 1572. Many palaces, villas, and churches were erected after his designs, and at the request of Philip II of Spain he drew a plan for the Escurial.
Aletsch′-glacier, the greatest glacier in Switzerland, canton Valais, a prolongation of the immense mass of glaciers connected with the Jungfrau, the Aletschhorn (14,000 feet) , and other peaks; about 15 miles long.
Aleurites, a tree belonging to the nat. ord. Euphorbiaceæ, is found in tropical and subtropical parts of the world. ”

“ But, as some one says, on the Aletsch the boundary mountains form an insignificant cup-lip to the glacier itself, which, to my knowledge, may be compared to the same on the Plaine-Morte only. The Oberland peaks, which from Grindelwald or Lauterbrunnen exhibit such a wonderful wealth of design, are comparatively tame from the basin of the Aletsch. When we think of the Jungfrau we always think of her as seen from the pastures of the Wengern Alp. Seen from the Aletsch she is not particularly striking. One’s whole attention is focussed on the broad, silent reaches of snow. ”

“ It is a curious fact, that in the valley of Hassli the temperature frequently rises instead of falling as you ascend; at the Grimsel, the temperature is at times higher than at Meyringen below, where the warmer winds are not felt so directly. The glacier of Aletsch, on the southern slope of the Jungfrau, and into which many other glaciers enter, terminates also at a considerable height, because it turns into the valley of the Rhone, through which the southern winds blow constantly. ”

“ From the shoulder of the Hochstetter Dome down a long valley between the giant snow peaks of the Mount Cook Range on the one hand, and the rocky buttresses of the Malte Brun and Liebig Ranges on the other, swollen at intervals by tributary ice-streams, flowing with imperceptible movement, comes the Great Tasman Glacier—a veritable mer de glace—eighteen miles in length. Some six miles from its terminal face the Ball Glacier descends from the south-eastern shoulder of Aorangi, and pours its huge slabs of broken ice and a rubble of moraine into the parent stream. ”

“ The small débris-covered ice-streams, too small to reach the water, are typical of a large class of glaciers in southern Alaska, which are slowly wasting away and have become buried beneath débris concentrated at the surface by reason of their own melting. The Galiano glacier is a good example of this class. The Hubbard and Dalton glaciers are fine examples of another class of ice-streams which flow into the sea and end in ice-cliffs, and which for convenience we call tide-water glaciers. Nowhere can finer or more beautiful examples of this type be found than those in view from Haenke island. ”

“ It has lateral and medial moraines, ice pinnacles, crevasses, and many other details peculiar to glaciers. From its extremity, which is dark with dirt and stones, there flows a stream of turbid water. It is, in fact, a miniature similitude of the ice-streams on the neighboring mountain, some of which are forty or fifty miles in length and many times wider in their narrowest part than the little glacier before us is long. The more thoroughly we become acquainted with the mountains of southern Alaska the more interesting and more numerous do the Alpine glaciers of the third order become. ”

“ As the tide fell, large pieces fell from this front, and avalanches of ice-fragments crashed down into the sea and raised waves that rocked our ship and set the ice-floes grinding together. On the other point of the crescent of this bay there lay the largest glacier, an ice-field that swept down from two mountain gorges, and, spreading out in fan shape, descended in a long slope to a moraine of sand, pebbles, and boulders. Across its rolling front this glacier measured at least three miles, and the low, level moraine was one mile in width. ”

“ Elias region form two groups. The ice-streams from the mountain are of the type found in Switzerland, and hence termed Alpine glaciers. The great plateau of ice along the ocean formed by the union and expansion of Alpine glaciers from the mountains belongs to a class not previously described, but which in this paper have been called Piedmont glaciers. The representative of the latter type between Yakutat bay and Icy bay is the Malaspina glacier. ”

“ A low temperature alone can do nothing without moisture, and this fact quickly disposes of the popular notion that glaciers invariably exist in cold countries. Thibet, for instance, and also some parts of Arctic North America are destitute of ice streams, though eternal cold may be said to reign supreme in these parts.
Imagine for a moment the higher mountains clear of snow and ice, and then watch for the formation of a glacier. Snow falls and fills up all the valleys and gullies, avalanches descend from the higher parts, and a great accumulation gathers in all hollows. ”

“ The bed of last year’s streams is of course filled up with hard-frozen snow, so that there is no exit for the waters till the cup is full. The moment it begins to overflow the cutting of the channel takes place. The pent-up waters are let loose and evidently operate with extraordinary force, excavating a deep cañon out of the glacier. The floating ice acquires a momentum, whereby it not merely gets ripped and broken up, but forced forward on to the dry glacier ahead, great tables of it being turned up on end or piled on one another two or three deep. ”

“ The glaciers of Jotunheim are almost Alpine—more than Alpine, indeed, in [206] the development of their glorious ice-cascades, but less than Arctic in the outreach of their lower extremities. The glaciers of the Tropics, again, present peculiarities of their own, due to the fact that the ice evaporates rather than melts. Thus their surfaces are dry and almost granitic in aspect. Their towering séracs seldom fall. Avalanches are much rarer than one would expect. Glacier streams are insignificant. Thus it is in the Bolivian Andes and thus also in the regions of Kenya and Ruwenzori. ”

“ It is one of the many fields of ice which stellates from a center fifteen miles back of the Muir front and covers the valley of the mountains between the Pacific and the headwaters of the Yukon river. Nine glaciers now discharge icebergs into the bay. All of these glaciers have receded from one to four miles in the past twenty years. Kate Field says, “In Switzerland a glacier is a vast bed of dirty air-holed ice that has fastened itself like a cold porous plaster to the Alps. In Alaska a glacier is a wonderful torrent that seems to have been frozen when about to plunge into the sea.” ”

“ For some reason or other the temperature gradually fell, and great glaciers forming in the northern regions, the highlands of Canada and the Arctic Circles, submerged Northern Europe and reduced Canada and half of the United States to the present condition of Greenland. Those who see glaciers to-day can form little idea of the enormous possibilities of semi-fluid ice. Only in Alaska, where the Muir Glacier empties itself into the Muir inlet at the rate of seventy feet a day, can we form any idea of the glacier as a destructive agency. ”

“ At best the surface was very bumpy, and I foresaw a bad time coming for the sledges. The ice phenomena would have struck any Alpine climber as curious. Every year there are added, even to the central and crevassed portion of an arctic glacier, accumulations of ice formed by the thawing and re-freezing of the winter snow, and these patchwork additions take the most unexpected forms. For instance, a crevasse that happens to be full of water will be roofed over with ice a few feet thick. If the rest of the water is then drained off a tunnel is formed, across which again crevasses may open. ”

“ Mazama, Rusk, Lava, Pinnacle and Avalanche glaciers lie beneath cliffs too steep to carry ice-streams. Their income is mainly collected from the slopes, and if they receive snow from the broad summit at all, it is chiefly in the avalanches of early summer. Nearly all the glaciers, however, are thus fed in part, the steep east and west faces making Mount Adams famous for its avalanches.
Mount Adams, seen from the northeast, with the Lyman glaciers in center, Rusk glacier on extreme left, and Lava glacier, right. The ridge beyond Lava glacier is the north-side route to the summit. ”

“ The cliffs at its head are being continually broken and worn away by the action of frost. The rocks that fall from them either tumble on to the névé and are carried down or roll into the bergschrund, and so get under the ice, where no doubt they are ground to dust, and may do some excavating in the process. That, however, can only be in the upper regions; lower down, the waters below the glacier are the excavating agent, rather than the glacier itself, except, perhaps, at the edge of some sub-glacial cliff beneath an icefall. ”

“ The nature, origin, and aspect of the moraines, the mode of melting of the ice beneath them, and the isolated pinnacles of ice which support large solitary 478 boulders, agree so entirely with descriptions of glaciers in other parts of the world, that it is unnecessary to dwell upon them. The large glaciers are often a good deal lower in their central parts than where they are covered by a bulky moraine; and a curious ravine-like hollow, between the moraine and the bare ice, which makes the former appear as if entirely disconnected from the glacier, is of very common occurrence. ”

“ Blocks seen to fall from particular points are afterwards noticed lower down. On the moraines rocks are found of a totally different mineralogical character from those composing the mountains right and left; and in all such cases strata of the same character are found bordering the glacier higher up. Hence the conclusion that the foreign boulders have been floated down by the ice. Further, the ends or “snouts” of many glaciers act like ploughshares on the land in front of them, overturning with irresistible energy the huts and châlets that lie in their path. ”

“ These ice-caps covering great regions are by far the most important types. Between these “polar” or “continental glaciers” and the “alpine” type there are many grades. Smaller detached ice-caps may rest upon high plateaus as in Iceland, or several tongues of ice coming down neighbouring valleys may splay out into convergent lobes on lower ground and form a “piedmont glacier” such as the Malaspina Glacier in Alaska. When the snow-field lies in a small depression the glacier may remain suspended in the hollow and advance no farther than the edge of the snow-field. ”

“ Mount Darwin sends its one great glacier sweeping down into the main stream; then the Hochstetter Dome stands at the head of the Tasman Glacier itself, and westward rise the noble summits of Mounts Elie de Beaumont, Green, and De la Bêche—the last a most beautiful triple peak, queen of the whole group, and over 10,000 feet in height. Still following round, the eye falls on the Rudolf Glacier descending from the peak of the same name, then Mounts Jervois, Spencer, Glacier Peak, and lastly Mount Haidinger, a fine flat-topped mountain clothed from base to summit in broken ice. ”

“ Reaching a level place, the speed of flow is reduced so that the surface becomes frozen over in cold weather. Snow falls upon the ice thus formed, and a roof is made, the remains of which, even at this advanced period of the summer, were two feet thick or more. The glacier in its onward movement is compressed between the Terrier and the De Geer range opposite, and every portion of it feels this compression, which, operating on the frozen roof of the river, bends it up into an icy tunnel of regular form. ”

“ Many persons who visited the Mer de Glace some twenty or more years ago remember that it then came down nearly to the level of the valley of Chamonix, while the Rhone glacier reached almost to where the lower hotel now stands. In old days, too, the two arms of the Fee glacier united below the Gletscher alp, so that the cows had to pass across the ice in order to reach their summer pastures. A period of advance is always preceded for some years by a noticeable swelling of the upper portions of glaciers ”

“ A column of ice, 1,400 feet high, he estimates to lie upon the ground with a pressure of nearly a quarter of a ton to each square inch of surface, nor does he find reason to doubt that the temperature of the earth's surface beneath the glacier is about 32°. He cites the fact that from beneath glaciers in Greenland muddy streams are continually discharged. It is possible, therefore, that the antarctic glaciers, covering vast level tracts, are prevented from accumulating to a thickness much exceeding 1,400 feet, by waste in the bottom portions, where constant melting and regelation are going on. ”