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 he had soon cleared away the earth, and hollowed out a kind of passage sloping gently down to the crust of ice.
He next attacked the brittle mass, which had been covered over with sand and earth for so many centuries. It would not take more than an hour to hollow out a subterranean retreat, or rather a burrow with walls of ice, which would keep in the heat, and therefore serve well for a resting-place during the short night.
Whilst Long was working away like a white ant, Hobson communicated the result of his observations to Mrs Barnett. He did not disguise from her that the construction of Victoria Island rendered him very uneasy. He felt sure that the thinness of the ice would lead to the opening of ravines on the surface before long; where, it would be impossible to foresee, and of course it would be equally impossible to prevent them. The wandering Island might at any moment settle down in consequence of a change in its specific gravity, or break up into more or less numerous islets, the duration of which must necessarily be ephemeral. He judged, therefore, that it would be best for the members of the colony to keep together as much as possible, and not to leave the fort, that they might all share the same chances.
Hobson was proceeding further to unfold his views when cries for help were heard.
Mrs Barnett started to her feet, and both looked round in every direction, but nothing was to be seen.
The cries were now redoubled, and Hobson exclaimed—
“The Sergeant! the Sergeant!”
And followed by Mrs Barnett, he rushed towards the burrow, and he had scarcely reached the opening of the snow-house before he saw Sergeant Long clutching with both hands at his knife, which he had stuck in the wall of ice, and calling out loudly, although with the most perfect self-possession.
His head and arms alone were visible. Whilst he was digging, the ice had given way suddenly beneath him, and he was plunged into water up to his waist.
Hobson merely said—
And creeping through the passage, he was soon at the edge of the hole. The poor Sergeant seized his hand, and he was soon rescued from his perilous position.