As I contend that many tidal waves are caused by icebergs plunging into the ocean, let us see what grounds there are for that belief. First, something causes the waves: they do not start of their own accord. If an iceberg were to plunge into the ocean, a great commotion would be raised and several large waves would be started. But how far would they run? That would depend upon many different conditions--such as the size of the wave and the force that set it moving. A pebble falling five feet will make but a small ripple, while a rock ten feet in diameter, falling one hundred feet, will make a mighty wave. Then, if no obstructions be met, and the wind be favorable, that wave would go a long way. According to Wells's "Natural Philosophy," it might get larger instead of smaller. "This wave," says he, "propagates itself
A wave is a form, not a thing; the form advances, but not the substance of the wave. Two icebergs might frequently plunge in from different directions, and send forth just such conditions as Wells writes about. Or the one plunging in first might be farther away, and as waves move comparatively slowly, they might frequently meet at some common centre, and be increased in size and force, as he suggests. Could anything else produce so large a wave? If not, why should we not give the greatest cause credit for the greatest effect? The wonderful ice-pressure can be produced from different causes: winds, The perplexing situations met with in the Arctic Circle, the grand scenes of every kind, and the things difficult to understand, remind one of the man reading the dictionary: the words were fine, but he couldn't make much of the story. It is so with the explorers: everything is grand; the ice roars, and crushes when everything is calm; the heavens are lighted up most beautifully when there is no storm; the winds blow terribly out of the clear sky: none of these things can be understood. Nansen's remarks about the tide having nothing to do with ice-pressure, must be accounted for in some other way. That other way is a tidal wave. In the same volume, farther on, he says: "The ice-pressure was not noticeable after 1 o'clock on Friday night until it suddenly recommenced last night. First I heard a rumbling outside, and some snow fell down from the rigging upon the tent-roof as I sat reading; I thought it sounded like packing in the ice, and just then the Fram received a violent shock, such as she had not received last winter. I was rocked backward and forward on the chest on which I was sitting. Finding that the trembling and rumbling continued, I went out. There was a loud roar of ice, packing to the west and northwest, which continued uniformly for a couple of hours or so. * * * Just after I had come on board again, shortly before noon, the ice suddenly began to press on again. I went out to have a look; it was again in the When speaking of ice-pressure, nearly all explorers speak of great ridges. Melville calls it a "frozen wave." Bernacchi says the ice was lifted seventy, eighty, and ninety feet. Nansen termed it a ridge; and all agree that they look like great ridges, or waves, that can be heard for miles in the distance before they reach the ship, and for a long time after they have passed. If the descriptions given by the several explorers do not correctly represent a set of great waves, I do not know how to describe them. Melville describes, in expressive manner, a scene in which ice-pressure played a part during his sojourn in the Arctic regions. "It was in one of these oppressive intervals succeeding a gale," says he, "when the roar and crash of the distant masses could be distinctly heard, that the floe in which
The reader will notice that these weird doings occurred after a storm; and during it the ice, as a whole, moved along with but slight disturbance. The swell that comes after a storm has no connection with it. If a storm raises no swell after raging continuously for ten to twenty-four hours, it would take a great deal to make me believe that after it had subsided it had anything to do with the swell that came later. Melville's description, just cited, proves to my mind that the whole affair Nansen's accounts of this subject are most appropriate. On page 278 of Volume I, he says: "We had kept company quite long enough with the old--now broken-up--floe, so worked ourselves a little way astern after dinner, as the ice was beginning to draw together. "Towards evening the pressure began again in earnest, and was especially bad around the remains of our floe, so that I believe we may congratulate ourselves on having left it. It is evident that the pressure here stands in connection with--is perhaps caused by--the tidal wave. It occurs with the greatest regularity. The ice Farther on, in the same volume, we read: "For when the packing begins in earnest it seems as though there could be no spot on the earth's surface left unshaken. First you hear a sound like the thundering rumbling of an earthquake far away on the great waste; then you hear it in several places, always coming nearer and nearer. The silent ice world re-echoes with thunders; Nature's giants are awakening to the battle. The ice cracks on every side of you, and begins to pile itself up; and all of a sudden you, too, On page 383 Nansen begins other descriptions that are worth reproducing: "Most violent pressures are beginning again. I must go on deck and look at it. The loud roar meets one as one opens the door. It is coming from the bow now, as well as from the stern. It is clear that the pressure ridges are being thrown up in both openings, so if they reach us we shall be taken by both ends and lifted lightly and gently out of the water. There is pressure near us on all sides. Creaking has begun in the old hummock on the port quarter; it is getting louder, and, so far as I can see, the hummock is slowly rising. A lane has opened right across the large floe on the port side; you can see the water, dark as it is. Now both pressure and noise get worse and worse; the ship shakes and I feel as if I myself were being gently lifted with the stern rail, where I stand gazing out at the welter of ice masses that resemble giant snakes writhing and twisting "No, that was not the end of the pressure. When I was on deck, at a quarter to 12, roaring and trembling began in the ice forward on the port side; then suddenly came one loud boom after another, sounding out in the distance, and the ship Concerning ice-pressure, Bernacchi, writing of his voyage in the Antarctic, on page 120, vividly conveys to the reader a picture of what he saw. "A deep sonorous roar was audible like the din of a battle; a battle indeed! A great battle of Nature was raging. We rushed down towards the shore from whence the noise came, and on reaching it a sight met our eyes which baffles description; a scene absolutely frightful in its grandeur. A moving mountain of ice had risen up; a sudden and terribleTHE TIDAL WAVE.