Chapter Thirteen.
At the North Pole.
The opening was so low and so narrow, that for the first fifty or sixty feet the explorers were I obliged to creep forward on their hands and knees; then it widened and became gradually higher, so that by the time they had penetrated a couple of hundred feet they were able to resume a perpendicular attitude. The cavern, if such it could be called, still however remained so narrow that it was only here and there possible for them to walk side by side. It was also very tortuous; and the heights varied momentarily, at one time compelling them to stoop almost double in order to pass beneath some immense projection, and anon increasing so greatly that the light of their torches failed to reach and reveal the roof. They observed several rifts or crevices to the right and left of them as they pressed forward, but, with one or two exceptions, these were quite impassable, and those which were not so were still so cramped that they offered no inducement to deviate from the main passage.
Groping thus in semi-darkness over painfully rough and broken ground, a full hour was spent, and the colonel was just expressing his conviction that they must have traversed a distance of fully two miles when a faint glimmer of daylight revealed itself on one of the rocky walls of the passage; and, turning sharply round an angle, the pair suddenly found themselves once more within a few yards of the open air.
Emerging into broad daylight a most wonderful spectacle greeted the two adventurous explorers. They found themselves standing on a narrow strip of coarse sandy beach at the bottom of an immense basin, measuring fully a mile in diameter, the sides of which were formed of lofty precipitous cliffs of volcanic rock, so smooth and so nearly vertical that nowhere, at least in their immediate neighbourhood, could they discover a spot capable of being scaled. Before them, and occupying the whole bottom of this enormous basin, stretched a placid lake, the water of which was as clear as crystal. A thin filmy veil of vapour rose everywhere from the surface of the water, softening the hard outlines of the more distant landscape, and imparting an aspect of dreamlike witchery and unreality which it would certainly have otherwise lacked.
“Why, the water is tepid!” exclaimed Sir Reginald, plunging his hand into the lake and raising a small quantity of its water in his palm, to ascertain by taste whether it was fresh or salt.
The colonel thereupon thrust his hand down, and satisfied himself by experiment of the truth of his companion’s statement. It was even more than tepid, it was positively warm.
The two were still discussing the probable reason for this phenomenon when their attention was suddenly arrested by a curious movement of the water in the centre of the lake. First a few tremulous ripples appeared, spreading outward from the centre; then the disturbance became more pronounced, until, within a minute, an area of some thirty or forty yards in diameter had assumed an appearance of violent ebullition. Suddenly a jet of steam and spray shot up out of the centre of this disturbed spot; and then, before either of the two bewildered spectators could find time to remark upon so curious a phenomenon, an immense column of purest crystal water shot into the air to a height of at least two hundred feet, and, gleaming and flashing in the sunbeams as it soared away above the level of the encircling cliffs, spread out into a dome-like sheet, and, leaving behind it aloft a dense cloud of vapour of dazzling whiteness, fell again into the lake in the form of a shower of boiling water.