The Ocean and Its Wonders/Chapter 9
t is well known that when fresh water becomes so cold that its temperature is 32° 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 debris 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, Esquimaux leaping over a chasm.
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 by 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 on 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 incorpoFloating ice.
incorporated with the new ice of the succeeding winter; and not unfrequently 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 M'Clintock 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 Foxwas 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, M'Clintock 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 past 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 snowdrift 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 up 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 Phœnix (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, &c. 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, &c., 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, &c., 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 illustration 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.
This work was published before January 1, 1929, and is in the public domain worldwide because the author died at least 100 years ago.
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