which may possibly be revolving with equal rapidity in an opposite direction -when masses not seldom twenty or thirty miles in diameter, and each weigh FORMS OF ICEBERGS. be utterly unable to resist their power. ing many millions of tons, clash together, imagination can hardly conceive a more appalling scene. The whalers at all times require unremitting vigilance to secure their safety, but scarcely in any situation so much as when navigating amidst these fields, which are more particularly dangerous in foggy weather, as their motions can not then be distinctly observed. No wonder that since the establishment of the fishery numbers of vessels have been crushed to pieces between two fields in motion, for the strongest ship ever built must needs Some have been uplifted and thrown upon the ice; some have had their hulls completely torn open; and others have been overrun by the ice, and buried beneath the fragments piled upon their wreck. The icebergs, which, as their name indicates, rise above the water to a much more considerable height than the ice-fields, have a very different origin, as they are not formed in the sea itself, but by the glaciers of the northern highlands. As our rivers are continually pouring their streams into the ocean, so many of the glaciers or ice-rivers of the Arctic zone, descending to the water-edge, are slowly but constantly forcing themselves farther and farther into the sea. In the summer season, when the ice is particularly fragile, the force of cohesion is often overcome by the weight of the prodigious masses that overhang the sea or have been undermined by its waters; and in the winter, when the air is probably 40° or 50° below zero and the sea from 28° to 30° above, the unequal expansion of those parts of the mass ex posed to so great a difference of temperature can not fail to produce the separation of large portions. Most of these swimming glacier-fragments, or icebergs, which are met with by the whaler in the Northern Atlantic, are formed on the mountainous west coast of Greenland by the large glaciers which discharge themselves into the fiords from Smith's Sound to Disco Bay, as here the sea is sufficiently deep to float them away, in spite of the enormous magnitude they frequently attain. As they drift along down Baffin's Bay and Davis's Strait, they not seldom run aground on some shallow shore, where, bidding defiance to the short summer, they frequently remain for many a year. Dr. Hayes measured an immense iceberg which had stranded off the little harbor of Tessuissak, to the north of Melville Bay. The square wall which faced toward his base of measurement was 315 feet high, and a fraction over three-quarters of a mile long. Being almost square-sided above the sea, the same shape must have extended beneath it; and since, by measurements made two days before, Hayes had discovered that fresh-water ice floating in salt water has above the surface to below it the proportion of one to seven, this crystallized mountain must have gone aground in a depth of nearly half a mile. A rude estimate of its size, made on the spot, gave in cubical contents about 27,000 millions of feet, and in weight something like 2000 millions of tons! Captain Ross in his first voyage mentions another of these wrecked bergs, which was found to be 4169 yards long, 3689 yards broad, and 51 feet high above the level of the sea. It was aground in 61 fathoms, and its weight was estimated by an officer of the "Alexander" at 1,292,397,673 tons. On ascending the flat top of this iceberg, it was found occupied by a huge white bear, who justly deeming "discretion the best part of valor," sprang into the sea before he could be fired at. The vast dimensions of the icebergs appear less astonishing when we consider that many of the glaciers or ice-rivers from which they are dislodged are equal in size or volume to the largest streams of continental Europe. Thus one of the eight glaciers existing in the district of Omenak, in Greenland, is no less than an English mile broad, and forms an ice-wall rising 160 feet above the sea. Further to the north, Melville Bay and Whale Sound are the seat of vast ice-rivers. Here Tyndall glacier forms a coast-line of ice over two miles long, almost burying its face in the sea, and carrying the eye along a broad and winding valley, up steps of ice of giant height, until at length the slope loses itself in the unknown ice-desert beyond. But grand above all is the magnificent Humboldt glacier, which, connecting Greenland and Washington Land, forms a solid glassy wall 300 feet above the water-level, with an unknown depth below it, while its curved face extends full sixty miles in length from Cape Agassiz to Cape Forbes. In the temperate zone it would be one of the mightiest rivers of the earth; here, in the frozen solitudes of the North, it slowly drops its vast fragments into the waters, making the solitudes around re-echo with their fall. As the Polar shores of continental America and Siberia are generally flat, and below the snow-line, they are consequently deprived both of glaciers and of the huge floating masses to which these give birth. In a high sea the waves beat against an iceberg as against a rock; and in calm weather where there is a swell, the noise made by their rising and falling is tremendous. Their usual form is that of a high vertical wall, gradually sloping down to the opposite side, which is very low; but frequently they exhibit the most fantastic shapes, particularly after they have been a long time. exposed to the corroding power of the waves, or of warm rains pelting them from above. A number of icebergs floating in the sea is one of the most magnificent spectacles of nature, but the wonderful beauty of these crystal cliffs never appears to greater advantage than when clothed by the midnight sun with all the splendid colors of twilight. "The bergs," says Dr. Hayes, describing one of these enchanting nights, "had wholly lost their chilly aspect, and glittering in the blaze of the brilliant heavens, seemed in the distance like masses of burnished metal or solid flame. Nearer at hand they were huge blocks of Parian marble inlaid with mammoth gems of pearl and opal. One in particular exhibited the perfection of the grand. Its form was not unlike that of the Colosseum, and it lay so far away that half its height was buried beneath the line of blood-red waters. The sun, slowly rolling along the horizon, passed behind it, and it seemed as if the old Roman ruins had suddenly taken fire. In the shadow of the bergs the water was a rich green, and nothing could be more soft and tender than the gradations of color made by the sea shoaling on the sloping tongue of a berg close beside us. The tint increased in intensity where the ice overhung the water, and a deep cavern near by exhibited the solid color of the malachite mingled with the transparency of the emerald, while in strange contrast a broad streak of cobalt blue ran diagonally through its body. The bewitching character of the scene was heightened by a thousand little cascades which leaped into the sea from these floating masses, the water being discharged from lakes of melted snow and ice which reposed in quietude far up in the valleys separating the high icy hills of their upper surface. From other bergs large pieces were now and then detached, plunging down into the water with deafening noise, while the slow moving swell of the ocean resounded through their broken archways." A similar gorgeous spectacle was witnessed by Dr. Kane in Melville Bay. The midnight sun came out over a great berg, kindling variously-colored fires on every part of its surface, and making the ice around the ship one great resplendency of gemwork, blazing carbuncles and rubies, and molten gold. In the night the icebergs are readily distinguished even at a distance by their natural effulgence, and in foggy weather by a peculiar blackness in the atmosphere. As they are not unfrequently drifted by the Greenland stream considerably to the south of Newfoundland, sometimes even as far as the fortieth or thirty-ninth degree of latitude (May, 1841, June, 1842), ships sailing through the north-western Atlantic require to be always on their guard against them. The ill-fated "President," one of our first ocean-steamers, which was lost on its way to New York, without leaving a trace behind, is supposed to have been sunk by a collision with an iceberg, and no doubt many a gallant bark has either foundered in the night, or been hurled by the storm against these floating rocks. |