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by the adjunction of higher ice, the elevation of its border by the pressure of the surrounding ice, or the irregularity of its own surface, several inches of ice must be added to its thickness on the returning winter, by the conversion of the snow-water into solid ice. This process repeated for many successive years, or ages, together with the enlargement of its under-side from the ocean, might be deemed sufficient to produce the most stupendous bodies of ice that have yet been discovered; at the same time that the ice thus formed, would doubtless correspond with the purity and transparency of that of fields in general.
Fields may sometimes have their origin in heavy close packs, which, being cemented together by the intervention of new ice, may become one solid mass. In this way are produced such fields as exhibit a rugged, hummocky surface.
Fields commonly make their appearance about the month of June, though sometimes earlier : -they are frequently the resort of young whales; strong north and westerly winds expose them to the Greenlandmen, by driving off the loose ice. Some fields exhibit a perfect level plain, without a fissure or hummock, so clear indeed, that I imagine, upon one which I saw, a coach might be driven a hundred miles in a direct line, without any obstruction. Most commonly, however, the surface contains some hummocks, which somewhat relieve the uniformity of intense light, by a tinge of delicate green, in cavities where the light gains admittance
in an oblique direction, by passing through a portion of ice.
The invariable tendency of fields to drift to the south-westward, even in calms, is the means of many being yearly destroyed. They have frequently been observed to advance a hundred miles in this direction, within the space of one month, notwithstanding the occurrence of winds from every quarter. On emerging from amidst the smaller ice, which before sheltered them, they are soon broken up by the swell, are partly dissolved, and partly converted into drift ice. The places of such are supplied by others from the north. White bears here find an occasional habitation, and will travel inany leagues from land upon the field They have been repeatedly met with, not only upon these continuous sheets of ice, but on the ice of close packs, to the utmost extent to which ships have penetrated.
On the tremendous Concussions of
The occasional rapid motion of fields, with the strange effects produced on any opposing substance, exhibited by such immense bodies, is one of the most striking objects this country presents, and is certainly the most terrific. They not unfrequently acquire a rotatory movement, whereby their circumference attains a velocity of several miles per hour. A field, thus in motion, coming in contact with another at rest, or more especially with a contrary direction of movement, produces a dreadful shock. A body of more than ten thousand millions of tons in weight, meeting with resistance, when in.
motion, the consequences may possibly be conceived! The weaker field is crushed with an awful noise; sometimes the destruction is mutual pieces of huge dimensions and weight, are not unfrequently piled upon the top, to the height of twenty or thirty feet, whilst doubtless a proportionate quantity is depressed beneath. The view of those stupendous effects in safety, exhibits a picture sublimely grand; but where there is danger of being overwhelmed, terror and dismay must be the predominant feelings. The whalefishers at all times require unremitting vigilance to secure their safety, but scarcely in any situation so much, as when navigating nidst those fields: in foggy weather, they are particularly dangerous, as their motions cannot then be distinctly observed. It may easily be imagined, that the strongest ship can no more withstand the shock of the contact of two fields, than a sheet of paper can stop a musket-ball. Numbers of vessels, since the establishment of the fishery, have been thus destroyed; some have been thrown upon the ice, some have had their hulls completely torn open, and others have been buried beneath the heaped fragments of the ice.
In the year 1804, I had a good opportunity of witnessing the effects produced by the lesser masses in motion. Passing between two fields of bay-ice, about a foot in thickness, they were observed rapidly to approach each other, and before our ship could pass the strait, they met with a velocity of three or four miles per hour: the one overlaid the other, and pre
sently covered many acres of surface. The ship proving an obstacle to the course of the ice, it squeezed up on both sides, shaking her in a dreadful manner, and producing a loud grinding, or lengthened acute tremulous noise, accordingly as the degree of pressure was diminished or increased, until it had risen as high as the deck. After about two hours, the velocity was diminished to a state of rest; and soon afterwards, the two sheets of ice receded from each other, nearly as rapidly as they before advanced. The ship, in this case, did not receive any injury, but had the ice been only half a foot thicker, she would probably have been wrecked.
In the month of May of the present year, (1813), I witnessed a more tremendous scene. Whilst navigating amidst the most ponderous ice which the Greenland seas present, in the prospect of making our escape from a state of besetment, our progress was unexpectedly arrested by an isthmus of ice, about a mile in breadth, formed by the coalition of the point of an immense field on the north, with that of an aggregation of floes on the south. north field, we moored the ship, in the hope of the ice separating in this place. I then quitted the ship, and travelled over the ice to the point of collison, to observe the state of the bar which now prevented our release. I immediately discovered that the two points had but recently met; that already a prodigious mass of rubbish had been squeezed upon the top, and that the motion had not abated. The fields continued to overlay each other with a majestic
motion, producing a noise resembling that of complicated machinery, or distant thunder. The pressure was so immense, that numerous fissures were occasioned, and the ice repeatedly rent beneath my feet. In one of the fissures, I found the snow on the level to be three and a half feet deep, and the ice upwards of twelve. In one place, hummocks had been thrown up to the height of twenty feet from the surface of the field, and at least twenty-five feet from the level of the water; they extended fifty or sixty yards in length, and fifteen in breadth, forming a mass of about two thousand tons in weight. The majestic unvaried movement of the ice, the singular noise with which it was accompanied,-the tremendous power exerted,-and the wonderful effects produced, were calculated to excite sensations of novelty and grandeur, in the mind of even the most careless spectator!
Sometimes these motions of the ice may be accounted for. Fields are disturbed by currents,-the wind, or the pressure of other ice against them. Though the set of the current be generally towards the south-west, yet it seems occasionally to vary the wind forces all ice to leeward, with a velocity nearly in the inverse proportion to its depth under water; light ice consequently drives faster than heavy ice, and loose ice than fields: loose ice meeting the side of a field in its course, becomes deflected, and its reaction causes a circular motion of the field. Fields may approximate each other, from three causes: first, If the lighter ice be to windward, it will, of ne
cessity, be impelled towards the heavier secondly, As the wind frequently commences blowing on the windward side of the ice, and continues several hours before it is felt a few miles distant to leeward, the field begins to drift, before the wind can produce any impression on ice on its opposite side; and, thirdly, which is not an uncommon case, by the two fields being impelled towards each other by winds acting on each from opposite quarters.
The closing of heavy ice, encircling a quantity of bay-ice, causes it to run together with such force, that it overlaps wherever two sheets meet, until it sometimes attains the thickness of many feet. Drift-ice does not often coalesce with such a pressure as to endanger any ship which may happen to be beset in it: when, however, land opposes its drift, or the ship is a great distance immured amongst it, the pressure is sometimes alarming.
The term icebergs has commonly been applied to those immense bodies of ice situated on the land, "filling the valleys between the high mountains," and generally exhibiting a square perpendicular front towards the sea. They recede backward inland to an extent never explored. Martin, Crantz, Phipps, and others, have described those wonders of nature, and all agree as to their manner of formation, in the congelation of the sleet and rains of summer, and of the accumulated snow, partly dissolved by the summer sun, which, on its decline,
freezes to a transport ice. They are as permanent as the rocks on which they rest: For although large portions may be frequently separated, yet the annual growth replaces the loss, and probably, on the whole, produces a perpetual increase. I have seen those styled the Seven Icebergs, situated in the valleys of the north-west coast of Spitzbergen; their perpendicular front may be about 300 feet in height; the green colour, and glistening surface of which, form a pleasing variety in prospect, with the magnificence of the encompassing snow-clad mountains, which, as they recede from the eye, seem to "rise crag above crag," in endless perspective.
Large pieces may be separated from those ice-bergs in the summer season, when they are particularly fragile, by their ponderous overhanging masses overcoming the force of cohesion; or otherwise, by the powerful expansion of the water, filling any excavation or deep-seated cavity, when its dimensions are enlarged by freezing, thereby exerting a tremendous force, and bursting the whole asunder.
Magnitude of Icebergs.
If all the floating islands of ice thus proceed from disruptions of the icebergs generated on the land, how is it that so few are met with in Greenland, and those comparatively so diminutive, whilst Baffin's Bay affords them so plentifully, and of such amazing size? The largest I ever saw in Greenland, was about a thousand yards in circumference, nearly square, of a regular flat surface, twenty feet above the level of the sea; and as it was composed of the most dense kind of ice, it must have been 150 or 160 feet in thickness, and in weight about two millions of tons. But masses have been repeatedly seen in Davis' Straits, near two miles in length, and one-third as broad, whose rugged mountainous summits were reared with various spires to the height of more than a hundred feet, whilst their base must have reached to the depth of a hundred and fifty yards beneath the surface of the sea. Others, again, have been observed, possessing an even surface, of five or six square miles in area, elevated thirty yards above the sea, and fairly run aground in water of ninety or a hundred fathoms in depth; the weight of which must have been upwards of two thousand millions of tons!
Pieces thus or otherwise detached, are hurled into the sea with a dreadful crash; if they are received into deep water, they are liable to be drifted off the land, and, under the form of ice-islands, or ice-mountains, they likewise Icebergs may arise in sheltered Bays still retain their parent name of icebergs. I much question, however, if all the floating bergs seen in the seas west of Old Greenland, thus derive their origin; their number is so great, and their dimensions so immense.
of the Land.
Spitzbergen is possessed of every character which is supposed to be necessary for the formation of the largest icebergs; high mountains, deep extensive valleys, intense
frost, and occasional thaws; yet here a berg is very rarely met with, and the largest I ever heard of, was not to be compared with the productions of Baffin's Bay. Icebergs, I therefore conclude, may have their principal origin in the deep sheltered narrow bays, with which Old or West Greenland abounds. In this respect it possesses a decided advantage over Spitzbergen, since, on the west side, the coast now alone visited, few sheltered spots occur; at least those situations the most protected from the influences of the wind and prevailing currents, are found annually to disembogue themselves of their ice. On the eastern coast, if we may rely on the charts, and credit the affirmations of the Dutch, many more suitable spots are offered, wherein ice may be increased for ages; the most prevailing winds, and the common set of the current on these shores, having no tendency to dislodge it, until its enormous growth has carried it beyond the limits of security and undisturbed rest. And from this Eastern coast it is, (which is favourable to the supposition,) that most of the icebergs which have been seen, seem to have drifted,-they being mostly met with in the vicinity of Cherry Island, or between it and the southern Cape of Spitzbergen, where the course of the current is supposed to be from the northeast towards the south-west. The ice of bergs invariably producing
pure fresh-water, when dissolved, is no argument against the majority having their origin amidst sea-water; for fields, which, from their flat surface, and large ex
tent, must have their rise on the bosom of the ocean, commonly afford a solution equally fresh.
Icebergs generated at a distance
from any known Land.
Müller relates a circumstance which intimates, that some icebergs have their origin in the wide expanse of the ocean. He informs us, that in the year 1714, one Markoff, a Cossack, with some other persons, were sent to explore the ocean north of Russia, by order of the Russian government; but being foiled in his object, by the immense aggregation of drift-ice, he conceived the design of trying during the winter season to travel over the then more compact ice. Accordingly, he prepared several of the country sledges, drawn by dogs; and, accompanied by eight persons, he set out on the 15th March (O. S.) from the mouth of the Yani, on the coast of Siberia, in latitude 71° N. and longitude about 132o E. He proceeded for seven days northward, until he reached the 77th or 78th degree of north latitude, when his progress was impeded by ice elevated into prodigious mountains. From the top of these, he could see nothing but mountainous ice to the northward; at the same time falling short of provisions for his dogs, he returned with difficulty: several of his dogs died for want, and were given to the rest for their support. On the 3d of April he reached the Siberian shore, after an absence of nineteen days, during which he travelled 800 miles.
Here, therefore, is a fact of a continent, if we may so speak, of