The Ocean and Its Wonders, R. M. Ballantyne [best motivational books .txt] 📗
- Author: R. M. Ballantyne
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Now, this incident suggests the probability, that, had the face of the glacier projected into deep water, the mass which broke off might have fallen into the sea without being broken to pieces, and might have floated away as a berg. We confess, however, to be partial to the view expressed by some writers, that the great glaciers continue year by year to thrust their thick tongues out to sea, until the projecting masses reach water sufficiently deep to float them, when they are quietly cracked off from their parent and carried away without any fall or plunge. The following remarks by Dr Kane will make this more clear. Writing of the iceberg, he says:
“So far from falling into the sea, broken by its weight from the parent glacier, it rises from the sea. The process is at once gradual and comparatively quiet. The idea of icebergs being discharged, so universal among systematic writers, and so recently admitted by myself, seems to me at variance with the regulated and progressive action of nature. Developed by such a process, the thousands of bergs which throng these seas should keep the air and water in perpetual commotion—one fearful succession of explosive detonations and propagated waves. But it is only the lesser masses falling into deep waters which could justify the popular opinion. The enormous masses of the Great Glacier (of Greenland) are propelled step by step, and year by year, until, reaching water capable of supporting them, they are floated off, to be lost in the temperatures of other regions...
“The height of the ice-wall at the nearest point was about three hundred feet, measured from the water’s edge; and the unbroken right line of its diminishing perspective showed that this might be regarded as its constant measurement. It seemed, in fact, a great icy table-land, abutting with a clean precipice against the sea. This is, indeed, characteristic of all those arctic glaciers which issue from central reservoirs, or mers de glace, upon the fords or bays, and is strikingly in contrast with the dependent or hanging glacier of the ravines.”
Elsewhere the same writer speaks of this glacier as a line of cliff, rising in a solid glassy wall to a height of three hundred feet above the water-level, and with an unfathomable depth below it; and its curved face, sixty miles in length, from Cape Agassiz to Cape Forbes, vanished into unknown space at not more than a single day’s rail-road travel from the pole. The interior with which it communicated, and from which it issued, was an unsurveyed mer de glace, or sea of ice, of apparently boundless dimensions; and from one part of this great cliff he saw long lines of huge bergs floating slowly away.
Here, we think, is ice enough and of sufficient dimensions to account for the largest bergs that were ever beheld.
It will be at once seen, then, that icebergs, though found floating in the sea, are not necessarily of the sea. They are composed entirely of fresh water, and arctic ships can at any time procure a plentiful supply of good soft drinkable water from the pools that are formed in the hollows of the bergs.
The risk of approaching icebergs in the arctic regions is not so great as when they are found floating further south; because when in their native regions they are comparatively tough, whereas on their southern journeys they become more or less disintegrated—in fact, the blow of an axe is sometimes sufficient to cause a rent, which in its turn will induce other rents and failings asunder, so that the whole mass runs the risk of being entirely broken up. Hence the danger of ships, in certain circumstances, venturing to anchor to them. Nevertheless this is a common practice—sometimes a necessity—among discovery ships and whalers. It is a convenient practice too; for many a vessel has been saved from absolute destruction by getting under the lee of a good sound iceberg, where she has lain as safely, for the time being, as if in a harbour.
When Captain McClure was endeavouring to make the north-west passage in 1851, he was saved, from what appeared to be at least very probable destruction, by a small iceberg. On the 17th of September he writes:
“There were several heavy floes in the vicinity. One, full six miles in length, passed at the rate of two knots, crushing everything that impeded its progress, and grazed our starboard-bow. Fortunately there was but young ice upon the opposite side, which yielded to the pressure; had it otherwise occurred, the vessel must inevitably have been cut asunder. In the afternoon we secured to a moderately-sized iceberg, drawing eight fathoms, which appeared to offer a fair refuge, and from which we never afterwards parted.”
To this lump of ice the ship clung with the tenacity of a bosom friend, and followed it, literally, through thick and thin! There is something almost ludicrous, as well as striking, in McClure’s account of their connection with this bit of ice. It conveyed them to their furthest north-east position, and back round the Princess Royal Islands—passed the largest within five hundred yards—returned along the coast of Prince Albert’s Land—and finally froze in at latitude 70 degrees 50 minutes north, longitude 117 degrees 55 minutes west, on the 30th September; during which circumnavigation they received many severe “nips,” and were frequently driven close to the shore, from which their dear friend the iceberg, small though he was, kept them off.
Icebergs assume almost every conceivable form, and are seen of every size—sometimes, also, in great numbers. Scoresby mentions one occasion on which he was surrounded by bergs to the number of several hundreds.
Now, all this ice that we have been speaking of, besides being, in a secondary way, a passive agent in the affairs of man (chiefly in barring his progress northward), is one of the most potent agents in the economy of nature. It is the means by which the world is kept cool enough for man and beast to dwell in. The polar regions—north and south—are, as it were, the world’s refrigerators; tempering the heated air of the south, and, in connection with the torrid zone, spreading throughout the Earth those beneficial influences which gladden the sphere of man’s temporal existence.
There are many things in this world which, up to within a few years back, have been to men a source of surprise and mystery.
Some of these problems have been solved by recent travellers, and not a few of them are referable to polar oceans and ice.
In many parts of our coasts we find very striking and enormously large boulder-stones lying on the beach, perfectly isolated, and their edges rounded away like pebbles, as if they had been rolled on some antediluvian beach strewn with Titanic stones. These boulders are frequently found upon the loose sands of the sea-shore, far removed from any rocks or mountains from which they might be supposed to have been broken; and, more than that, totally different in their nature from the geological formations of the districts in which they are found. “Whence came these?” has been the question of the inquisitive of all ages, “and how came they there?”
There may, for aught we know to the contrary, be more than one answer to these questions; but there is at least one which is quite satisfactory as to how and whence at least some of them have come. Ice was the means of conveying these boulders to their present positions.
It has been said that once upon a time a large part of this country was under the dominion of ice, even as the polar regions and some of the mountains and valleys of Norway are at the present day; that the boulders we see in elevated places were conveyed thither by glacier action; and that when the glacial period passed away, they were left there on the hill-sides—sometimes almost on the mountain-tops. But this is not the question we are considering just now. We are now inquiring into the origin of those huge boulders that are found upon our coasts and on the coasts of other lands—boulders which could not have rolled down from the hills, for there are no hills at all near many of them; and those hills that are near some of them are of different geological formation.
This question will be answered at once, and one of the phenomena of arctic ice and oceanic agency will be exhibited, by reference to the recent discoveries of the celebrated arctic voyager, Dr Kane of the American Navy.
While wintering far beyond the head of Baffin’s Bay, and beyond the most northerly point, in that direction, that had at that time been reached by any previous traveller, Dr Kane made many interesting observations and discoveries. He seems to have penetrated deep into the heart of Nature’s northern secrets. Among other things, he ascertained the manner in which boulders are transported from their northern home.
The slow, creeping movement of glaciers, to which we have already referred, is one means whereby large boulders are formed. At the lower edge of one of the glaciers of Norway we saw boulders, thirty or forty feet in diameter, which had been rolled and forced, probably for ages, down the valley by the glacier, and thrust out on the sea-beach, where they lay with their angles and corners rubbed off and their surfaces rounded and smoothed as completely as those of the pebbles by which they were surrounded.
Had these boulders been formed in the arctic regions, they might have been thrust out upon the thick solid crust of the frozen sea, which in time would have been broken off and floated away; thus rafting the boulders to other shores. The formation of boulders, and their positions, are facts that we have seen. Their being carried out to sea by ice-rafts is a fact that Dr Kane has seen and recorded. On the wild rocky shores where his ship was set fast, there was a belt of ice lining the margin of the sea, which he termed the “ice-belt,” or the “ice-foot.” This belt never melted completely, and was usually fast to the shore. In fact it was that portion of the sea-ice which was left behind each spring when the general body of ice was broken up and swept away. Referring to this, he writes:
“The spot at which we landed I have called Cape James Kent. It was a lofty headland, and the land-ice which hugged its base was covered with rocks from the cliffs above. As I looked over this ice-belt, losing itself in the far distance, and covered with its millions of tons of rubbish, greenstones, limestones, chlorite, slates, rounded and angular, massive and ground to powder, its importance as a geological agent, in the transportation of drift, struck me with great force.
“Its whole substance was studded with these varied contributions from the shore; and further to the south, upon the now frozen waters of Marshall Bay, I could recognise raft after raft from the last year’s ice-belt which had been caught by the winter, each one laden with its heavy freight of foreign material.
“The water torrents and thaws of summer unite with the tides in disengaging the ice-belt from the coast; but it is not uncommon for large bergs to drive against it and carry away the growths of many years. I have found masses
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