Chapter Nine
Formation of Ice—Dangers of Disrupting Ice—Anecdote—Drifting Ice—Drift of the “Fox”—“Nipping” Anecdote—Loss of the “Breadalbane.”
It is well known that when fresh water becomes so cold that its temperature is 32 degrees of Fahrenheit’s scale, it loses its liquid form and becomes ice. A somewhat lower temperature than this is necessary to freeze salt water; the reason being, that greater force is required to expel the salt which the sea holds in solution,—which salt is always more or less expelled in the process of freezing.
Ice commences to form in the shape of needles, which shoot out at angles from each other. In smooth water, under the influence of intense cold, the process is rapid, and a thin cake soon covers the water, and increases in thickness hour by hour. But when the sea is agitated the process is retarded, and the fine needles are broken up into what arctic navigators call sludge. This, however, soon begins to cake, and is broken by the swell into small cakes; which, as they thicken, again unite, and are again broken up into larger masses. These masses, by rubbing against each other, have their edges slightly rounded up, and in this form receive the name of pancake ice.
When a quantity of ice covers the ocean in a wide level sheet of considerable extent, it is called an ice-field. Fields of this kind are often seen by navigators hundreds of miles in extent, and nearly thirty feet thick. Ice of such thickness, however, only shows five or six feet above water. When fields are broken by heavy ocean-swells, the edges are violently forced up, and fall in débris on the surface; thus hummocks or mounds are formed.
When field-ice breaks up under the influence of an ocean-swell, caused by a storm, the results are terrific.
An exceedingly graphic account of an incident of this kind is given by Dr Brown, in his “History of the Propagation of Christianity.” He writes:—
“The missionaries met a sledge with Esquimaux, turning in from the sea, who threw out some hints that it might be as well for them to return. After some time, their own Esquimaux hinted that there was a ground-swell under the ice. It was then scarcely perceptible, except on lying down and applying the ear close to the ice, when a hollow, disagreeable, grating sound was heard ascending from the abyss. As the motion of the sea under the ice had grown more perceptible, they became alarmed, and began to think it prudent to keep close to the shore. The ice also had fissures in many places, some of which formed chasms of one or two feet; but as these are not uncommon in ice even in its best state, and the dogs easily leap over them, they are frightful only to strangers.
“As the wind rose to a storm, the swell had now increased so much that its effects on the ice were extraordinary, and really alarming. The sledges, instead of gliding smoothly along as on an even surface, sometimes ran with violence after the dogs, and sometimes seemed with difficulty to ascend a rising hill. Noises, too, like the report of cannon, were now distinctly heard in many directions, from the bursting of the ice at a distance. Alarmed at these frightful phenomena, our travellers drove with all haste towards the shore; and, as they approached it, the prospect before them was tremendous. The ice having burst loose from the rocks, was tossed to and fro, and broken in a thousand pieces against the precipices with a dreadful noise; which, added to the raging of the sea, the roaring of the wind, and the driving of the snow, so overpowered them as almost completely to deprive them of the use of their eyes and ears.
“To make the land was now the only resource that remained, but it was with the utmost difficulty that the frightened dogs could be driven forward; and as the whole body of the ice frequently sank below the summits of the rocks, and then rose above them, the only time for landing was the moment it gained the level of the coast—a circumstance which rendered the attempt extremely nice and hazardous.
“Both sledges, however, succeeded in gaining the shore, and were drawn up off the beach, though not without great difficulty. Scarcely had they reached it, when that part of the ice from which they had just escaped burst asunder, and the water, rushing up from beneath, instantly precipitated it into the ocean. In a moment, as if by a signal, the whole mass of ice for several miles along the coast, and extending as far as the eye could reach, began to break up, and to be overwhelmed by the waves. The spectacle was awfully grand. The immense fields of ice rising out of the ocean clashing against each other, and then plunging into the deep with a violence which no language can describe, and with a noise like the discharge of a thousand cannon, was a sight which must have filled the most unreflecting mind with feelings of solemnity.
“The Brethren were overwhelmed with amazement at their miraculous escape, and even the Esquimaux expressed gratitude to God for their deliverance.”
Such is the terrible aspect in which field-ice is seen when broken up and converted into smaller masses or floes. When these lie closely together the mass is called pack-ice; in which shape it usually drifts away with the southern currents, and, separating as it travels south, is met with in loose floating masses, of every fantastic form. There is always, as we have said, a large quantity of floe and pack-ice in the polar seas, which becomes incorporated with the new ice of the succeeding winter; and not infrequently whale and discovery ships get frozen into the pack, and remain there as firmly embedded as if they lay high and dry on land. When the pack is thus re-frozen, it usually remains stationary; but there are occasions and circumstances in which the entire body of a pack drifts slowly southward even during the whole year; showing clearly that oceanic circulation is by no means arrested by the icy hand of the hyperborean winter.
A very remarkable drift of this kind is recorded by Captain McClintock of the Fox, which is worthy of being noticed here, as illustrative of the subject we are now considering and also as showing in a remarkable manner the awful dangers to which navigators may be exposed by the disruption of the pack in spring, and the wonderful, almost miraculous, manner in which they are delivered from imminent destruction.
In attempting to cross Baffin’s Bay, by penetrating what is called the “middle ice,” the Fox was beset, and finally frozen in for the winter; and here, although their voyage may be said to have just commenced, they were destined to spend many months in helpless inactivity and comparative peril and privation. Their little vessel lay in the centre of a field of ice of immense extent; so large, indeed, that they could not venture to undertake a journey to ascertain its limits. Yet this field slowly and steadily descended Baffin’s Bay during the whole winter, and passed over no fewer than 1385 statute miles in the space of 242 days, during which period the Fox was firmly embedded in it!
It is with difficulty the mind can form any adequate conception of the position of those voyagers;—unable to move from their icy bed, yet constantly drifting over miles and miles of ocean; uncertain as to the where or the when of their deliverance from the pack; exposed to the terrible dangers of disrupting ice, and surrounded by the depressing gloom of the long arctic night.
At length deliverance came; but it came surrounded by terrors. In February, McClintock writes thus: “Daylight reveals to us evidences of vast ice-movements having taken place during the dark months, when we fancied all was still and quiet; and we now see how greatly we have been favoured, what innumerable chances of destruction we have unconsciously escaped. A few days ago, the ice suddenly cracked within ten yards of the ship, and gave her such a smart shock that every one rushed on deck with astonishing alacrity. One of these sudden disruptions occurred between me and the ship, when I was returning from the iceberg. The sun was just setting as I found myself cut off… At length I reached a place where the jagged edges of the floes met; so crossed, and got safely on board.”
Again, in March, he says, “Last night the ice closed, shutting up our lane; but its opposite sides continued for several hours to move vast each other, rubbing off all projections, crushing and forcing out of the water masses four feet thick. Although one hundred and twenty yards distant, this pressure shook the ship and cracked the intervening ice.”
Soon after that, a heavy gale burst upon them from the south-east, encircling them with snow-drift so dense that they could neither hear nor see what was going on twenty yards off. At night the ship became suddenly detached from her wintry bed, and heeled over to the storm, inducing them to believe that the whole pack had been broken in, and was pressing against them. This was not the case. A large mass of ice had protected them; but at a distance of about fifty yards, ice of four and a half feet thick had been crushed to atoms. Soon after, the protecting mass yielded, and the Fox received a nip which lifted her stern about a foot, while occasional groaning from her sturdy little hull replied to the wild surgings of the ice without.
But all this was as nothing compared with the scene of desperate turmoil and confusion which took place when the ice finally broke up, and a gale raised a fearful swell; so that the Fox found herself surrounded by huge masses, which tossed and ground against each other furiously, and any two of which pieces could have crushed in her sides as if she had been made of walnut shell. Gradually the pack opened out, and the vessel, by aid of wind and steam, was mercifully delivered from her dangerous position.
Before passing from the subject of risk to navigators to the consideration of other forms and aspects of polar ice, let us take a glance at an effectual case of nipping. There have been many partial and severe nips, the descriptions of which are all more or less graphic; but few ships have come so suddenly to the end of their career as did the Breadalbane, a small vessel that was used as a transport ship to the expedition in search of Sir John Franklin in 1852. One who was on board when it occurred thus describes it:—
Sunday, August 21st.—About ten minutes past four, the ice passing the ship awoke me, and the door of my cabin, from the pressure, opened. I hurriedly put on my clothes, and on getting on deck found some hands on the ice endeavouring to save the boats; but the latter were instantly crushed to pieces. They little thought, when using their efforts to save the boats, that the ship was in so perilous a situation.
I went forward to hail the Phoenix (another ship that was fortunately near) for men to save the boats; and whilst doing so, the ropes by which we were secured parted, and a heavy nip took us, making every timber creak, and the ship tremble all over. I looked in the main hold, and saw the beams giving way. I hailed those on the ice, and told them of our critical situation, they not for one moment suspecting it. I then rushed to my cabin, hauled out my portmanteau on deck, and roared like a bull to those in their beds to jump out and save their lives. The startling effect on them might be more easily imagined than described. On reaching the deck, those on the ice called out to me to jump over the side, that the ship was going over. I left my portmanteau, and jumped over the side on the loose ice, and with difficulty, and with the assistance of those on the ice, succeeded in getting on the unbroken part, with the loss of the slippers I had on when quitting the vessel, with wet feet, etcetera. The cold was little thought of at the exciting moment—life, not property, being the object to be saved.
“After being on the ice about five minutes, the timbers, etcetera, in the ship cracking up as matches would in the hand, it eased for a short time; and I, with some others, returned to the ship, with the view of saving some of our effects.
“Captain Inglefield now came running towards the ship, and ordered me to see if the ice was through it. On looking down into the hold, I saw all the beams, etcetera, falling about in a manner that would have been certain death to me had I ventured down there. But there was no occasion for that (I mean to ascertain the fact of the ice being through), it being too evident that the ship could not last many minutes. I then sounded the well, and found five feet in the hold; and, whilst in the act of sounding, a heavier nip than before pressed out the starboard bow, and the ice was forced right into the forecastle. Every one then abandoned the ship, with what few clothes they saved—some with only what they had on. The ship now began to sink fast, and from the time her bowsprit touched the ice until her mast-heads were out of sight, did not occupy above one minute and a half!
“It was a very sad and unceremonious way of being turned out of our ship. From the time the first nip took her, until her disappearance, did not occupy more than fifteen minutes.”
Such is the account of the fate of the Breadalbane. While we read it, we cannot help feeling that many arctic ships must have perished in a similar manner. It is wonderful, nevertheless, how many of those that dare the dangers of the ice survive the conflict. Undoubtedly this is owing, to a large extent, to the fact that ships’ bottoms are rounded; so that when a severe nip takes place, there is a tendency in the ice to slip under their rounded bottoms, and squeeze the vessels up out of the water. Were it not for this, few ships that have gone to those seas would ever have returned.
A catastrophe such as that which befell the Breadalbane shows the immense power of field-ice. Hundreds of somewhat similar incidents might be cited to illustrate this power; but we content ourselves with the selection of one instance, which exhibits it in a remarkable manner, and at the same time shows the way in which heavy vessels are sometimes forced out of the water.
In the year 1836, Captain Back commanded the Terror, which was sent out to make geographical discoveries in the polar regions, and spent the winter of that year in the ice. Few ships have undergone severer tests than did the Terror on that voyage. The severest treatment she experienced was in the spring, when the disruption of the winter ice began to take place. The evening of the 7th of March was specially fraught with danger. We quote the gallant commander’s graphic account:—
“Ominous rushing sounds were heard far off to the north-east and north-west. These gradually drew nearer as the flood made its way, either under the compact bodies that withstood the shock, or along the cracks and openings—gaining in these latter a furious velocity, to which everything seemed to yield.
“It happened that there were several of these around the ship; and when they opened on us like so many conduits pouring their contents to a common centre, the concussion was absolutely appalling, rending the lining and bulkheads in every part, loosening some shores and stanchions, so that the slightest effort would have thrown them down, and compressing others with such force as to make the turpentine ooze out of their extremities. One fir plank, placed horizontally between the beams and the shores actually glittered with globules. At the same time the pressure was going on from the larboard side, where the three heaviest parts of the ruin of the floe remained, cracked here and there, but yet adhering in firm and solid bodies. These, of course, were irresistible; and after much groaning, splitting, and cracking, accompanied by sounds like the explosion of cannon, the ship rose fore and aft, and heeled over about ten degrees to starboard.”
Again, on the 11th, Back says: “At this time she showed symptoms of suffering in the hull, which was evidently undergoing a severe ordeal. Inexplicable noises, in which the sharp sounds of splitting and the harsher ones of grinding were most distinct, came in quick succession, and then again stopped suddenly, leaving all so still that not even a breath was heard.
“In an instant the ship was felt to rise under our feet, and the roaring and rushing commenced with a deafening din alongside, abeam and astern, at one and the same instant. Alongside, the grinding masses held the ship tight as in a vice; while the overwhelming pressure of the entire body, advancing from the west, so wedged the stern and starboard quarter, that the greatest apprehensions were entertained for the stern-post and framework abaft.
“Some idea of the power exerted on this occasion may be gathered from this:– At the moment which I am now describing, the fore-part of the ship was literally buried as high as the flukes of the anchors in a dock of perpendicular walls of ice; so that, in that part, she might well have been thought immovable. Still, such was the force applied to her abaft, that after much cracking and perceptible yielding of the beams, which seemed to curve upwards, she actually rose by sheer pressure above the dock forward; and then, with sudden jerks, did the same abaft. During these convulsions, many of the carpenters and others stationed below were violently thrown down on the deck, as people are in an earthquake. It was a moment of intense suspense.
“On the 16th, another rush drove irresistibly on the larboard quarter and stern, and forcing the ship ahead, raised her on the ice. A chaotic ruin followed… The ship was careened fully four streaks, and sprang a leak as before. Scarcely were ten minutes left us for the expression of our astonishment that anything of human build could outlive such assaults, when another equally violent rush succeeded; and in its way toward the starboard quarter threw up a rolling wave thirty feet high, crowned by a blue square mass of many tons, resembling the entire side of a house, which, after hanging for some time in doubtful poise on the ridge, at length fell with a crash into the hollow, in which, as in a cavern, the after-part of the ship seemed embedded. It was, indeed, an awful crisis, rendered more frightful from the mistiness of the night and dimness of the moon.
“The poor ship cracked and trembled violently, and no one could say that the next minute would not be her last—and, indeed, his own too, for with her our means of safety would probably perish.”
It is unnecessary to give additional instances of this kind, in order to show the terrible power of field-ice. Indeed, it requires little in the way of illumination to prove that masses of solid matter, many thousands of tons in weight, can, when in motion, utterly destroy the most powerful engines of human construction.
We shall now turn our attention to another, and a very prominent form, in which arctic ice presents itself—namely, that of icebergs.
Chapter Ten
Icebergs—Their Appearance and Forms—Their Cause—Glaciers—Their Nature and Origin—Anecdote of Scoresby—Risk among Icebergs—McClure’s Experience
There are not only ice-fields, ice-floes, etcetera, in the polar seas, but there are ice-mountains, or bergs.
It was long a matter of uncertainty as to where and how those immense mountains, that are met with occasionally at sea, were formed. We are now in a position to tell definitely where they originate, and how they are produced. They are not masses of frozen sea water. Their birth-place is in the valleys of the far north, and they are formed by the accumulation of the snows and ice of ages. This is a somewhat general way of stating the matter; but our subsequent explanations will, we trust, make our meaning abundantly clear.
Icebergs are found floating in great numbers in the arctic seas. They drift southward each spring with the general body of polar ice, and frequently travel pretty far south in the Atlantic before the heat of the water and atmosphere united accomplishes their dissolution. They sometimes travel as far south as Florida with the southerly current that flows along that coast; but the warm waters of the Gulf Stream, together with its northerly flow, form an impassable barrier between these ice-mountains and Europe.
Icebergs assume every variety of form, and almost every size. They sometimes resemble castles, sometimes churches with glittering spires, and sometimes the peaked and jagged mountains of Norway. They are also frequently seen in the form of immense misshapen and top-heavy masses.
In size they vary from one hundred to seven or eight hundred feet in height. One iceberg, seen by Ross in Baffin’s Bay, was above two miles in length, nearly the same in width, and fifty feet high. But in stating this, we have not given the reader any idea of its vast proportions; for it is well known that all icebergs, or masses of ice, have a much greater proportion of their bulk under than above water—in other words, they sink very deep. The relative proportion that sinks depends on the nature of the ice. Of some kinds, there is usually ten times as much below as there is above water; of other kinds, there may be eight or five parts below. In all cases there is much more below than above so that a mountain of a hundred feet high—if afloat—may be safely calculated to be a mass of ice not far short of a thousand feet thick.
As these bergs float southward with the currents, they melt very rapidly. The heat of the sun and the action of the waves gradually round off the sharp angles and topple down the spires that characterised them in the land of their birth. The process of dissolution, too, is carried on internally; for rain and melted water on the surface percolates through the mass, rendering it porous. As the waves cut away the base, the centre of gravity is thrown out, and the whole berg turns over with a terrible crash. Sometimes loud reports like cannon-shots are heard, and the huge mountain splits asunder; while, not unfrequently, the whole berg falls into a heap of chaotic ruins, and floats away in a mass of smaller pieces which disappear gradually in their parent sea.
The formation of icebergs has, as we have said, puzzled mankind for many years. Their existence has long been known: for, even before men dared to venture their lives in the polar regions, navigators, in crossing the Atlantic Ocean, frequently met with these marble-like mountains; and, what is worse, sometimes ran at full speed against them, and were sunk with all on board. Bergs are frequently enveloped in dense fogs, caused by the cold atmosphere by which they are surrounded condensing the moisture of the warmer atmosphere which they encounter on their voyage southward; hence they are exceedingly dangerous to navigation. But now to speak of their formation.
Many of the great valleys of the far north are completely filled up with solid ice. Observe, we do not say that they are merely covered over with ice; they are absolutely filled up with it from top to bottom. Those ice-masses are known by the name of glaciers; and they are found in most of the elevated regions of the Earth,—on the Alps and the mountains of Norway, for instance,—but they exist in greater abundance about the poles than elsewhere.
Glaciers never melt. They have existed for unknown ages, probably since the world began; and they will, in all likelihood, continue to exist until the world comes to an end,—at least until the present economy of the world terminates. They began with the first fall of snow, and as falls of snow during the long winters of the polar regions are frequent and heavy, the accumulated masses are many feet deep, especially in places where drifts are gathered—sometimes fifteen, twenty, thirty, and even forty feet deep. The summer sun could not melt such drifts entirely. New snow was added each winter, until the valleys of the far north were filled up; and so they remain filled up to this day.
In order to understand the nature of glaciers clearly, let us turn back to those remote ages that rolled over this Earth long before man was created. Let us in spirit leap back to the time when no living creature existed, even before the great mastodon began to leave his huge foot-prints on the sands of time.
We have reached one of the large valleys of the arctic regions. It is solemn, grand, and still. No merry birds, no prowling creatures, are there to disturb the universal calm. The Creator has not yet formed the living creatures and pronounced them “very good.” It is the world’s first winter. As we look upward to the sky, we observe the first white snow-flakes falling gently to the ground. They reach it, and, for the first time, that valley is covered with a garment of virgin snow. The valley is upwards of two miles broad. It rises from the sea, and goes far back into the mountains, perhaps to the extent of ten or twelve miles. The mountains that flank it are five or six thousand feet high. We have seen such valleys in Norway, within the arctic circle. Before that first winter has passed, many and many a fall of snow has thickened and pressed down that first coat; and many a furious storm has caught up the snow from the mountain-tops and swept it into the valley, adding to and piling up the mass, and packing it firmly down.
Spring arrives. The short but warm arctic summer bursts upon that vale, melting the surface of the snow; and the water thus produced sinks through the mass, converting it into a sort of thick slush—half snow, half water,—not liquid, yet not solid; just solid enough to lie there apparently without motion; yet just liquid enough to creep by slow, absolutely imperceptible degrees, down the valley. The snow in all the mountain gorges is similarly affected: it creeps (it cannot be said to flow) out and joins that in the vale. But we cannot perceive any of the motion of which we are writing. The mass of snow seems to be as still and motionless as the rocks on which we stand; nay, if we choose we may walk on its hard surface almost without leaving the slightest print of our foot. But if we throw a large stone on the surface of the snow and mark the spot, and return again after many days, we shall find that the stone has descended the valley a short distance. We shall also observe that the snow has now a variety of markings on its surface; which might lead us to fancy, had we not known better, that it had once been a river, which, while raging down to the sea with all its curling rapids and whirling eddies, had been arrested in all instant by the ice-king and frozen solid,—in fact, it has all the graceful lines and forms of fluidity, with all the steady, motionless aspect of solidity. It really moves, this vast body of snow; but, like the hour hand of a watch, its motion cannot be recognised, though we should observe it with prolonged, unflagging attention. We have called it a vast body of snow, but this is only comparatively speaking. It will be vaster yet before we have done with it. At present it is but a thick semi-fluid covering, lying at the bottom of this ancient arctic vale.
The brief summer ends. Much of the winter snow has been melted and returned to the sea; but much, very much more, is still lying deep upon the ground. The world’s second winter comes. The first frost effectually puts a stop to all the melting and moving that we have been describing. The snow-river no longer moves—it is arrested. The water no longer percolates through the snow—it is frozen. The mass is no longer semi-fluid—it is solid ice; and the first step in the process of a glacier’s formation is begun.
Thereafter this process is continued from year to year, each winter adding largely to its bulk, each summer deducting slightly therefrom. The growing mass of ice ascends the mountain-sides, swallows the rocks and shrubs and trees in its progress, until its body becomes a thousand feet thick: the extreme summits of the mountain-peaks alone tower above the snowy waste, and the mass at the bottom is now, by the pressure of superincumbent masses, pure ice, hard and clear as crystal.
When the great glacier grows old it still maintains its stealthy downward motion during every summer. It has reached the shore, and has been pushed, like a huge white tongue, out into the sea.
“But what has all this to do with icebergs?” it may be inquired. Much, very much. It is common enough, in commenting on a child, to speak of the parent. The glacier is the mother of the iceberg.
When, in the world’s early morning, the embryo glacier reached the sea, its thin edges were easily broken off by the waves; but as it increased and still further encroached, these edges became thicker and thicker, until at last a wall of pure ice, several hundred feet high, presented its glittering front to the ocean. It was hard and massive; the sun of summer had little effect on its frigid face, and it seemed to bid defiance to the sea itself. But things often are not what they seem. Each billow sapped its foundation; it soon began to overhang its base. At length the cohesion of the mass was not sufficient to sustain its weight. A rending, accompanied by sounds like heaven’s artillery, took place; the crystal mountain bowed its brow and fell with thunderous crash upon the water; then, rocking slowly under the impulse of its dread plunge, the first iceberg floated off to sea!
It is right to remark here that this explanation is, to some extent, disputed—at least there is a difference of opinion as to the manner in which the iceberg leaves its parent glacier. There is no dispute as to its origin. This difference will be explained shortly in a quotation from Dr Kane’s work; meanwhile, in support of the present theory, let us listen to the words of one who saw with his own eyes something similar to what has been described. Dr Scoresby, than whom a better man never explored the arctic seas, says:—
“In July 1818, I was particularly fortunate in witnessing one of the grandest effects which these polar glaciers ever present. A strong north-westerly swell, having for some hours been beating on the shore, had loosened a number of fragments attached to the iceberg, and various heaps of broken ice denoted recent shoots of the seaward edge. As we advanced towards it, with a view of proceeding close to its base, I observed a few little pieces fall from the top; and while my eye was fixed upon the place, an immense column, probably fifty feet square, and one hundred and fifty feet high, began to leave the parent ice at the top, and, leaning majestically forward, with an accelerated velocity fell, with an awful crash, into the sea.