Ice barrier

“ The Great Ice Barrier, also called the Ross Barrier, lies between South Victoria Land and King Edward VII. Land and has an extent of about 515 miles. The first to reach this mighty ice formation was Sir James Clark Ross in 1841. He did not dare approach the great ice wall, 100 feet high, with his two sailing ships, the Erebus and the Terror, whose progress southward was impeded by this mighty obstacle. He examined the ice wall from a distance, however, as far as possible. ”

“ Any tourist who has crossed or ascended an Alpine glacier with only a knapsack to carry, can understand the difficulty of dragging a cartload of provisions, etc., over such accumulations of iceberg fragments and of sea-ice squeezed and crumbled up between them. It is evident that we must either find a natural breach in this Arctic barrier or devise some other means of scaling it. ”

“ In one place the ice suddenly arched up like a bow while we were looking at it, burst into fragments, collapsed at the exterior margins of fracture, and by the work of a moment created a long barrier line of ruins ten feet high. Our position was one of peril. We had crossed two miles of ice. A change of tide relieved the strain, and we returned.
“The nearest break-up to our homestead floe is about one hundred and fifty yards off. It is now to the south; though our position, constantly changing, alters the bearing by the hour. ”

“ Insulation inside and out is the subject we are now attacking.
The young ice is going to and fro, but the sea refuses to freeze over so far—except in the region of Pram Point, where a bay has remained for some four days holding some pieces of Barrier in its grip. These pieces have come from the edge of the Barrier and some are crumbling already, showing a deep and rapid surface deposit of snow and therefore the probability that they are drifted sea ice not more than a year or two old, the depth of the drift being due to proximity to an old Barrier edge. ”

“ A floe is a detached portion of a field; a large area of floes, closely compact together, is known as pack-ice; while drift-ice is loose ice in motion, and not so firmly welded as to prevent a ship from forcing her way through the yielding fragments.
IN AN ICE-PACK, MELVILLE BAY.
This “pack-ice,” however, is the great obstacle to Arctic exploration; and frequently it presents a barrier which no human enterprise or skill can overpass. At times, it has been found possible to cut a channel through it, or it breaks up and opens a water-way through which the bold adventurer steers. ”

“ This was one of the places in which the barrier is within the floe ice several miles.
"The temperature being so low in the summer months, there is but little chance of the ice melting or disappearing, as from accounts frequently takes place in the Arctic Ocean. Your time being unlimited will allow you to wait some days in a situation to make experiments.
"I conceive that the ice of the permanent barrier changes very little from year to year: along the line of our exploration it looks too solid and fast to be moved by any thing short of a continued temperature. ”

“ It is fronted by an undulating barrier, the van of a mighty ice-sheet that is being forced outward from the high interior of the Antarctic Continent and apparently is sweeping over low hills, plains, and shallow seas as the great Arctic ice-sheet once pressed over Northern Europe. The barrier surface, seen from the sea, is of a faint golden brown colour. It terminates usually in cliffs ranging from 10 to 300 ft. in height, but in a very few places sweeps down level with the sea. The cliffs are of dazzling whiteness, with wonderful blue shadows. ”

“ Several heavy pieces of ice were passed, evidently the fragments of the barrier or broken-up bergs, of which it was very remarkable we had not seen one during a run of one hundred and sixty miles along the barrier; from which, no doubt, some must occasionally break away. ”

“ By the time the outside ice has moved away so as to leave only the floes grounded on the bar the inside ice breaks up into loose masses, moving up and down with wind and current and ready to move off through the first break in the barrier. ”

“ My hypothesis of the solidity of the Barrier -- that is, of its resting upon underlying land -- seems to be confirmed at all points by our observations during our twelve months' stay on it. In the course of the winter and spring the pack-ice is forced up against the Barrier into pressure-ridges of as much as 40 feet in height. ”

“ It is rather pushed from behind than moving forward by its own gravitation. The flow is probably different also in this respect, that, like a rapid river, there is a sort of rotatory movement of the ice of a glacier which is plastic by virtue of its disintegrated grains, each surrounded with a film of saline water, whereas very little of such movement would occur in the case of the barrier ice, and consequently the marks of stratification remain visible in the bergs which are calved from it. ”

“ Ice-foot. A sheath of ice adhering along the shores of polar lands. The formation may be composed of attached remnants of floe-ice, frozen sea-spray and drift-snow. Nunatak. An island-like outcrop of rock projecting through a sheet of enveloping land-ice. Shelf-ice. A thick, floating, fresh water ice-formation pushing out from the land and continuous with an extensive glacier. Narrow prolongations or peninsulas of the shelf-ice may be referred to as ice-tongues or glacier-tongues. Barrier is a term which has been rather loosely applied in the literature of Antarctic Exploration. ”

“ But as the above-mentioned causes continue to act, the ice is also elevated by a perpetual aggregation of particles, till by a series of similar operations an icy mound or barrier is formed, so high as to force the water over the opposite bank, and thus produce an apparent inundation. ”

“ As we approached the promontory on the south of Crown-Prince Rudolf’s Land, we came upon innumerable icebergs, from one hundred to two hundred feet high, which made an incessant cracking and snapping sound in the sunshine. The Middendorf glacier, with an enormous sea-wall, ran towards the north to a great distance. Deep layers of snow and great rents in the sea-ice, the consequence of the falling-in of icebergs, filled the intervening spaces between them. Into these fissures we were continually falling, drenching our canvas boots and clothes with sea-water. ”

“ The pressure of the great body of snow above, the change of the atmospheric conditions, assisted by gravity, are the causes which enter into the formation of the solid glacier ice. These conditions may be increased or diminished by earthquakes and mild winters. Like a great river it advances toward the mouth of the valley, and as the immense body of ice moves downward, it brings with it by erosion huge pieces of rock, earth, and trees. ”

“ Then we have the struggle and confusion which attend the encounter of the young glacier with the first obstacles. An irresistible impulse urges the still half-formed ice over the edge, and it is transformed in a moment into a maze 343 of towers and blue abysses, of walls of marble-like snow seamed with the soft veins which mark each year's fall, of crystal-roofed and fretted vaults hung with pendant icicles. ”

“ Now and then one broke and fell apart before our eyes, sending up a funnel-shaped spray of color,—rose, pale green, or azure.
At every blast of the steamer's whistle great masses of ice came thundering headlong into the sea—to emerge presently, icebergs. Canoeists approach glaciers closely at their peril, never knowing when an iceberg may shoot to the surface and wreck their boat. Even larger craft are by no means safe, and tourists desiring a close approach should voyage with intrepid captains who sail safely through everything. ”

“ After the melting of the snow there appears besides a number of inequalities, and the clefts previously covered with a fragile snow-bridge now gape before the wanderer where he goes forward, with their bluish-black abysses, bottomless as far as we can depend on ocular evidence. At some places there are also to be found in the ice extensive shallow depressions, down whose sides innumerable rapid streams flow in beds of azure-blue ice, often of such a volume of water as to form actual rivers. ”

“ Picture this, and you will have an image of power not to be seen by the action of any other forces upon the earth.
The disturbance of the water was inconceivably fine. Waves of enormous magnitude were rolled up with great violence against the glacier, covering it with spray; and billows came tearing down the fiord, their progress marked by the crackling and crumbling ice, which was everywhere in a state of wildest agitation for the space of several miles. Over the smaller icebergs the water broke completely, as if a tempest were piling up the seas and heaving them fiercely against the shore. ”

“ But the slaughter among the seals and penguins would have been horrible with us, and many dogs might have been carried away on the breaking sea-ice. The tied-up ones lay under the lee of a line of cases, each in his own hole. They curled up quite snugly buried in the snow-drift when blizzards were blowing, and lay exactly in the same way when sledging on the Barrier, the first duty of the dog-driver after pitching his own tent being to dig holes for each of his dogs. ”

“ Illumined by the sun, the spray and angular crystal masses are indescribably beautiful. Some of the discharges pour in fragments from clefts in the wall like waterfalls, white and mealy-looking, even dusty with minute swirling ice-particles, followed by a rushing succession of thunder-tones combining into a huge, blunt, solemn roar. Most of these crumbling discharges are from the excessively shattered central part of the ice-wall; the solid deep-blue masses from the ends of the wall forming the large bergs rise from the bottom of the glacier. ”

“ Occasional glimpses unfold the polish, the colors, and the graceful winding of sea-shells. A strong current in connection with the wind forces us, I am glad to say, to a more safe and comfortable distance. The last ten minutes has given us a startling illustration of the dangers of which we have been forewarned: a crack like a field-piece was followed by the falling of ice, on the opposite side of the berg, attended with a sullen roar.
We round to, and take the breeze in our faces. The ice is up the wind, square before us, and we must after it by a tack or two. ”

“ Early in the morning, the wind freshened, and blew in toward the island; the ice piling against the rocky precipice under our lee, and opening in broken masses to windward. The Rescue managed to make fast to a crag between us and the shore, but our ice-anchors missed. At four in the afternoon we were within rifle-shot of the land, and still drifting; the wind a gale, and the sea-swell coming in heavily. ”

“ The crowded and crushed snow masses, nevé-like emerged upon all the lower shoulders of the huge crest in glacial fields of ice. Here their Arctic currents, sweeping around the lower summits, were reinforced by new accessions, springing from these lesser altitudes, which in confusion poured upon them, and by many avenues of obstruction and accidents of interference, repulse and rupture, converted the great multiplied ice zone, encircling the whole congery of peaks, and plunging outward over vertical escarpments to lower levels, into a stupendous spectacle of chaos. ”

“ Standing on our little deck, and looking out on the floe, we had the strange spectacle of an undulating solidity, a propagated wave borne in swell-like ridges, as if our ice was a carpet shaken by Titans. I can not convey the effect of this sublime spectacle. The ice, broken into polyhedric masses, gave at a few hundred yards no indications to the eye of the lines of separation; besides which, the infiltration of salt water had no doubt increased the plasticity of the material. ”

“ So the guide sullenly struck his ice-axe into the fissure, and climbed up it hand over hand, and took his lunatic up and down the Dent Blanche at a time when its ascent ought by all the laws of ice-craft to have been impossible.
CROSSING GLACIERS.
To turn from rock to snow climbing. Accidents are constantly happening on glaciers; yet the observance of the most elementary precautions ought to make such accidents absolutely impossible.
An open glacier, of course, is safe enough under any circumstances. ”

“ Ice, unlike water, is brittle, so it splits up into crevasses whenever the glacier flows over a steep or uneven 10 rocky bed. High up, where snow still lies, these chasms in the ice are often bridged over, and if a person ventures on one of these snow bridges it may break, and he may fall down the crevasse, which may be so deep that no bottom can be found to it. He is then either killed by the fall or frozen to death. If, as I have explained before, several climbers are roped together, they form a long string, like the tail of a kite, and not more than one is likely to break through at a time. ”

“ The boulders are detached fragments, which fell from various rocky heights overhanging the ice-stream, rested on the surface of the ice-sheet, were borne along by it through hundreds of miles, and when, in the course of ages untold, the climate became milder, and the glaciers gradually shrunk and eventually disappeared, these fragments, often bearing the marks of ice-scraping, and oftener rounded by ice-action, fell to the soil beneath, and remain to this day, to bear their silent witness to the course once taken by the giant ice-stream. ”