Ice jam

“ Trimmer first pointed out in what manner the unequal failure of support caused by the liquefaction of underlying or intercalated snow and ice might give rise to such complicated foldings.*
(* See chapter 12.)
When "ice-jams" occur on the St. Lawrence and other Canadian rivers (latitude 46 degrees north) , the sheets of ice, which become packed or forced under or over one another, assume in most cases a highly inclined and sometimes even a vertical position. ”

“ To the vagaries of the temperature he must reconcile himself as best he may. But let his bête noire, the snow—if so violent an antithesis be permissible—appear, and he will be on the alert at once. The snow-flakes, delicately adjusting themselves to one another as they settle down upon the ice, build up among their crystals myriads of tiny air-cavities, and the whole forms a veritable blanket which hinders radiation. It is warm for the same reason that a down comfortable is—it prevents the escape of heat. Now, what shall our ice-farmer do? ”

“ They sit in the sun, when they are tired of skating, and see that though a torrid luminary beats down on the frozen surface, burning and browning the faces of their friends, the ice remains perfectly dry and unmelted; they trudge through snow, and find that they are not wet; they see the thermometer marking anything up or down to thirty degrees of frost, and go out coatless and very likely hatless, and are conscious only of an agreeable and bracing warmth ”

“ A multitude of grounded icebergs showed a shoal, which appears to bar the northern entrance to Jones's Sound; and, during the night, a sudden gale from the north, together with high water in the tides, set them all floating and dancing around us in a very exciting style. Edging constantly along large floe-pieces, we were eventually carried next day into the packed ice, through which our way had to be found under double-reefed sails, the two pretty screw-schooners thrashing away in gallant style, until a dead calm again left us to steam our best ”

“ But this building-up of the rink requires immense patience and forethought. Night after night when the building is going on,{28} and the weather is warm and beastly, the head iceman, if he is really competent, will sit up through the long tale of dark hours, keeping himself awake with coffee, and watching the thermometer to see when it registers sufficient degrees of frost to enable him to put more water on to the ice. He will wait all through a cloudy night, hoping for the sky to clear, in order to get a half inch more foundation. ”

“ A fresh wind makes the cold very unbearable. In walking to-day, my beard and mustache became one solid mass of ice. I inadvertently put out my tongue, and it instantly froze fast to my lip. This being nothing new, costing only a smart pull and a bleeding abrasion afterward, I put up my mittened hands to ‘blow hot’ and thaw the unruly member from its imprisonment. Instead of succeeding, my mitten was itself a mass of ice in a moment: it fastened on the upper side of my tongue, and flattened it out like a batter-cake between the two disks of a hot griddle. ”

“ At any temperature below 32° F.,—that is, freezing-point,—the movement of heat is sufficient to loosen the molecules of water from their rigid bonds of cohesion. But at 32° the movement is so diminished that the atoms lock themselves together, and unite in a solid. This act of union, however, is controlled by well-known laws. To the unintelligent eye a block of ice seems neither more interesting nor more beautiful than a sheet of glass; but to the instructed mind the ice is to the glass what an oratorio of Handel is to the scream of a ballad-singer. Ice is music, glass is noise ”

“ Standing on our little deck, and looking out on the floe, we had the strange spectacle of an undulating solidity, a propagated wave borne in swell-like ridges, as if our ice was a carpet shaken by Titans. I can not convey the effect of this sublime spectacle. The ice, broken into polyhedric masses, gave at a few hundred yards no indications to the eye of the lines of separation; besides which, the infiltration of salt water had no doubt increased the plasticity of the material. ”

“ Balanced around its heart, far down in the deep, and in its cold solidity “dry as summer dust”—poised upon its centre with perfect exactness, it is evident that the loss of a single ton of ice shifts that centre, shifts it an ounce-notch on the bar of the mighty scale, destroys the equilibrium, and subjects the whole to the necessity of some small movement in order to regain its rest. ”

“ Our lives were only a wearing repetition of what had gone before—fierce cold, alarms, the roaring and tumbling of the ice pack, tremendous squeezes and pressures from the floes, and night and day the wheezing of the steam pumps, pumping, forever pumping. It seemed almost a reasonable supposition to conclude that we must have the whole Arctic Ocean nearly pumped dry to judge by the length of time we had been at it and by the huge masses of ice banked up against our bulwarks and spreading out over the floes where the streams of sea water flowing from our scuppers had frozen. ”

“ In the course of a tramp to-day about noon, the thermometer standing at -18°, I came across a wonderful instance of the yielding elasticity of ice under intense pressure. About two hundred yards from the brig, on her starboard quarter, was an unbroken plain of level ice, which before our recent break-up used to form one of my daily walks. It measured one hundred and thirty paces in its longer diameter and eighty-five in its shorter, and its thickness I ascertained this morning was over five feet. ”

“ The strong floe of ice-table under ice-table, and hummock upon hummock, makes our position one of nearly complete solidity. We are glued up in ice; and to liberate us, some fearful disruption must take place. Twenty-five feet of solid ice is no feeble matrix, for a brig drawing but ten. Yet the water is wider, and still widening around us; so that now we hold on—that is, our floe holds on, to the great mass to the north of us, like a little peninsular cape.
“To the south every thing is in drifting motion—water, sludge, frost-smoke—but no seals. ”

“ We have butted several times against projecting floes, but it is as unmoved as solid rock. Very foggy: Rescue not visible. Thermometer at 29 degrees.
“We recognize, among the floe fragments around us, old play-fellows. Here we played foot-ball; there we skated; by this hummock crag stood my thermometers; and here I shot a bear. We are passing slowly from them, or they from us. Now and then a rubbish pile will show itself, cresting the pure ice. Even an old champagne basket, full of nothing but sadly-pleasant associations, is recognized upon a distant floe. ”

“ I had hardly welcomed the spectacle when I saw that we had passed upon a new belt of ice that was obviously unsafe. To the right and left and front was one great expanse of snow-flowered ice. The nearest solid floe was a mere lump, which stood like an island in the white level. To turn was impossible; we had to keep up our gait. We urged on the dogs with whip and voice, the ice rolling like leather beneath the sledge-runners; it was more than a mile to the lump of solid ice. Fear gave to the poor beasts their utmost speed, and our voices were soon hushed to silence. ”

“ Daily the sun got lower; so did the mercury in the thermometer; and often for days there was no sight of the former because of flying snow and the deep haze of frost-fog. The ice set more and more firmly about the Bowhead, and the pack which ground and crushed against the edge of the shore ice outside the headland no longer made any answering movement in the frozen stretch about her. The winter was upon them, and there were times when their ice igloo was put to severe tests as a frost defender. ”

“ Nothing can be conceived more completely embodying inhospitable desolation. From mast-head the eye traveled wearily over a broad champaigne of modulating ice, crowned at its ridges with broken masses, like breakers frozen as they rolled toward the beach. ”

“ The thermometer had been at 21° and 23° for several nights, and scarcely rose above 32° in the daytime. Our little harbor at Barlow’s Inlet was completely blocked in by heavy masses; the new ice gave plenty of sport to the skaters; but on shipboard it was « 70 » uncomfortably cold. As yet we had no fires below; and, after drawing around me the India-rubber curtains of my berth, with my lamp burning inside, I frequently wrote my journal in a freezing temperature. “This is not very cold, no doubt”—I quote from an entry of the 8th—“not very cold to your forty-five minus men of Arctic winters ”

“ I wish them luck; but the thermometer fifty-seven degrees below freezing is unfavorable to a fête chainpêtre.
“December 12. Every thing solid, and looking as if it had always been so; yet, a few days ago, I had this journal of mine stitched up in its tarred canvas-bag, and ready for a fling upon the ice four times in the twenty-four hours. The floes have stopped abrading each other, and are driving ahead right peacefully, with our brig mounted on top: how far we are from the edges, it is too dark to see. ”

“ No bird with a well-regulated mind would possibly trust himself out in this temperature.”
On the debit side, the temperatures reached unbelievable depths. 57° below zero was recorded by our thermometers (the spirit ones, for the mercurial bulbs froze solidly at around -40°) . The pack ice reached thicknesses of thirty-five and forty feet below the water where underrunning floes, freezing together, consolidated into a kind of glacial layer cake. ”

“ Those parts of the external world from which the influence of the sun is withdrawn for the greatest length of time thus become intensely cold, excepting in the immediate vicinity of the polar openings, where the issue of warm air, from the internal cavity, tempers the atmosphere: but at a short distance from the verge of the opening the very influence of this warm air generates cold, by parting rapidly with its latent heat and condensing into snow and hail, which causes the circle of ice between [146] the 70th and 80th degrees of latitude, called the “icy hoop.” ”

“ The ice once formed in such cavities, only melts slowly; for one knows that ice in melting, absorbs 60° of heat; and where find this heat in an air always very cold and nearly still? During a great cold, the ice forms with great promptness, while it melts with much slowness, even when the temperature of the air is several degrees above zero; what must then not be this slowness when the temperature of the interior air only rises in summer one degree above freezing point. It would need several summers to melt this ice if it did not reform each winter. ”

“ But as 1879 faded into 1880, we drifted to the northward, and the Arctic winter struck us in all its cold fury, we were [Pg 133] given a choice opportunity to try to our hearts’ content ice of every thickness, formed under every temperature from barely freezing down to -60° F., and we could no longer blink the facts. ”

“ Crash!" went the cakes of ice as they came up the incline, and slid down the long wooden chutes, where the men hooked them off and piled them up. Pile after pile was made of the ice, until it was stacked up like an ice berg, inside the store house.
"Why doesn't the ice melt when the hot summer comes?" asked Hal.
"Because this building keeps the hot sun off the ice," explained the foreman. "Very little heat can get in our ice house, and it takes heat to melt ice. ”

“ The men measure out an area six feet by three feet, and take a preliminary temperature of the surface-ice by inserting a thermometer in a drilled hole. Then the ice begins to fly, and it is not long before they are down one foot. Nevertheless it would surprise those acquainted only with fresh water ice to find how tough, sticky and intractable is sea-ice. It is always well to work on a definite plan, channelling in various directions, and then removing the intervening lumps by a few rough sweeps of the pick. ”

“ They’re what make icebergs.”
“How on earth can they make icebergs?” asked Jim, studying the precipitous face of the glacier.
“Water cuts under ’em and they break off, and the pieces are the bergs,” explained the captain. “That’s what we call calving.”
“Well, it’s the prettiest colored thing I’ve ever seen,” declared Jim. “It’s for all the world like a giant opal and constantly changing. Gosh, it doesn’t look like any ice I ever saw.”
The Narwhal was now sailing close to the outer edge of the pack ice and a sharp lookout was kept for seals or whales. ”

“ At least this thickness is required if the ice is to last properly, for even in mid-winter the most sickening series of climatic catastrophes may occur, which, unless there is good thickness of ice originally built up, may spoil the rink altogether. For on hot sunny days, though the surface of the ice remains quite dry, very great evaporation occurs, and the dryness of the air drinks up the melted ice before it visibly or tangibly becomes water. ”

“ The rate at which ice is formed decreases as the thickness of the floe increases, and it ceases to be formed as soon as the floe becomes a non-conductor of the temperature of [4] the air by the increase of its mass, or when the driving of the ice-tables one over the other, or the enormous and constantly accumulating covering of snow, places limits to the penetration of the cold. ”