And so Hobson had not been mistaken about the point of rupture. It was the isthmus which had yielded in the shock of the earthquake. Not a trace was to be seen of the American continent, not a single cliff, even the volcano on the west had disappeared. Nothing but the sea everywhere.
The island on this side ended in a cape, coming to an almost sharp point, and it was evident that the substratum of ice, fretted by the warmer waters of the current and exposed to all the fury of the elements, must rapidly dissolve.
The explorers resumed their march, following the course of the fracture, which ran from west to east in an almost straight line. Its edges were not jagged or broken, but clear cut, as if the division had been made with a sharp instrument, and here and there the conformation of the soil could be easily examined. The banks- half ice, half sand and earth-rose some ten feet from the water. They were perfectly perpendicular, without the slightest slope, and in some places there were traces of recent landslips. Sergeant Long pointed to several small blocks of ice floating in the offing, and rapidly melting, which had evidently been broken off from their island. The action of the warm surf would, of course, soon eat away the new coast-line, which time had not yet clothed with a kind of cement of snow and sand, such as covered the rest of the beach, and altogether the state of things was very far from reassuring.
Before taking any rest, Mrs Barnett, Hobson, and Long, were anxious to finish their examination of the southern edge of the island. There would be plenty of daylight, for the sun would not set until eleven o’clock P.M. The briliant orb of day was slowly advancing along the western horizon, and its oblique rays cast long shadows of themselves before the explorers, who conversed at intervals after long silent pauses, during which they gazed at the sea and thought of the dark future before them.
Hobson intended to encamp for the night at Washburn Bay. When there eighteen miles would have been traversed, and, if he were not mistaken, half his circular journey would be accomplished. After a few hours’ repose he meant to return to Fort Hope along the western coast.
No fresh incident marked the exploration of the short distance between Walruses’ Bay and Washburn Bay, and at seven o’clock in the evening the spot chosen for the encampment was reached. A similar change had taken place here. Of Washburn Bay, nothing remained but the curve formed by the coast-line of the island, and which was once its northern boundary. It stretched away without a break for seven miles to the cape they had named Cape Michael. This side of the island did not appear to have suffered at all in consequence of the rupture. The thickets of pine and birch, massed a little behind the cape, were in their fullest beauty at this time of year, and a good many furred animals were disporting themselves on the plain.
A halt was made at Washburn Bay, and the explorers were able to enjoy an extended view on the south, although they could not see any great distance on the north. The sun was so low on the horizon, that its rays were intercepted by the rising ground on the west, and did not reach the little bay. It was not, however, yet night, nor could it be called twilight, as the sun had not set.
“Lieutenant,” said Long, “if by some miracle a bell were now to ring, what do you suppose it would mean?”
“That it was supper-time,” replied Hobson. “Don’t you agree with me, Mrs Barnett?”
“Indeed I do,” replied the lady addressed, “and as our cloth is spread for us, let us sit down. This moss, although slightly worn, will suit us admirably, and was evidently intended for us by Providence.”
The bag of provisions was opened; some salt meat, a hare paté from Mrs Joliffe’s larder, with a few biscuits, formed their frugal supper.
The meal was quickly over, and Hobson returned to the southwest angle of the island, whilst Mrs Barnett rested at the foot of a low fir tree, and Sergeant Long made ready the night quarters.
The Lieutenant was anxious to examine the piece of ice which formed the island, to ascertain, if possible, something of its structure. A little bank, produced by a landslip, enabled him to step down to the level of the sea, and from there he was able to look closely at the steep wall which formed the coast. Where he stood the soil rose scarcely three feet above the water. The upper part consisted of a thin layer of earth and sand mixed with crushed shells; and the lower of hard, compact, and, if we may so express it, “metallic” ice, strong enough to support the upper soil of the island.
This layer of ice was not more than one foot above the sea-level. In consequence of the recent fracture, it was easy to see the regular disposition of the sheets of ice piled up horizontally, and which had evidently been produced by successive frosts in comparatively quieter waters.
We know that freezing commences on the surface of liquids, and as the cold increases, the thickness of the crust becomes greater, the solidification proceeding from the top downwards. That at least is the case in waters that are at rest; it has, however, been observed that the very reverse is the case in running waters-the ice forming at the bottom, and subsequently rising to the surface.
It was evident, then, that the floe which formed the foundation of Victoria Island had been formed in calm waters on the shores of the North American continent. The freezing had evidently commenced on the surface, and the thaw would begin at the bottom, according to a well-known law; so that the ice-field would gradually decrease in weight as it became thawed by the warmer waters through which it was passing, and the general level of the island would sink in proportion.
This was the great danger.
As we have just stated, Hobson noticed that the solid ice, the ice-field properly so called, was only about one foot above the sea-level! We know that four-fifths of a floating mass of ice are always submerged. For one foot of an iceberg or ice-field above the water, there are four below it. It must, however, be remarked that the density, or rather specific weight of floating ice, varies considerably according to its mode of formation or origin. The ice-masses which proceed from sea water, porous, opaque, and tinged with blue or green, according as they are struck by the rays of the sun, are lighter than ice formed from fresh water. All things considered, and making due allowance for the weight of the mineral and vegetable layer above the ice. Hobson concluded it to be about four or five feet thick below the sea-level. The different declivities of the island, the little hills and rising ground, would of course only affect the upper soil, and it might reasonably be supposed that the wandering island was not immersed more than five feet.
This made Hobson very anxious. Only five feet! Setting aside the causes of dissolution to which the ice-field might be subjected, would not the slightest shock cause a rupture of the surface? Might not a rough sea or a gale of wind cause a dislocation of the ice-field, which would lead to its breaking up into small portions, and to its final decomposition? Oh for the speedy arrival of the winter, with its bitter cold! Would that the column of mercury were frozen in its cistern! Nothing but the rigour of an Arctic winter could consolidate and thicken the foundation of their island, and establish a means of communication between it and the continent.
Hobson returned to the halting-place little cheered by his discoveries, and found Long busy making arrangements for the night; for he had no idea of sleeping beneath the open sky, although Mrs Barnett declared herself quite ready to do so. He told the Lieutenant that he intended to dig a hole in the ice big enough to hold three persons — in fact to make a kind of snow-hut, in which they would be protected from the cold night air.
“In the land of the Esquimaux,” he said, “nothing is wiser than to do as the Esquimaux do.”
Hobson approved, but advised the Sergeant not to dig too deeply, as the ice was not more than five feet thick.
Long set to work. With the aid of his hatchet and ice-chisel............