“I see nothing against it. If the world is not habitable again now it never will be. It is a good two days since the contact now, and if the atmosphere had been burnt up or carried away by the attraction of the comet it would either be much colder or much hotter than that.”
“Very well then, up it comes, and then we shall get our last question answered.”
It was Alan who thus questioned and answered his father. All had gone well with the refugees of Mount Austral and the remnant of the Aerian race. Their science and their faith in themselves had been triumphantly justified by the event and had carried them safely through the sternest ordeal that man had ever been called upon to face.
And now there was only one more chance to be met, one more problem to be solved. The temperature showed that the earth still possessed an atmosphere, but was that atmosphere capable of supporting human life? If yes, all would be well and they could go forth into the wasted world and possess and replenish it. If no, then all their labour would have been in vain and they might as well have died in battle or with those friends and kin who had taken their silent and dignified farewell of the world in the last days of the State of Aeria.
They had a calorimeter and a pressure-gauge communicating with the outer world to tell the temperature and the height of the water in the valley. The former, after rising for a few hours to over a thousand degrees, had now sunk back to normal, while the latter stood at thirty feet above the entrance doors to the cavern.
The machinery for raising the sluice-gate was put into motion and they watched it with almost breathless anxiety lest the straining or shifting of the rocks, which had been very perceptible during the terrific convulsions which had apparently lasted for nearly ten hours, should have so dislocated the grooves that the gate could not be raised.
There were a few preliminary creaks and groans, a hitch and an increased strain on the lifting chains, and then the great sheet of steel rose easily and smoothly to the top of the channel and the pent-up waters rushed forth in a black boiling flood through the narrow opening and roared away, foaming and tossing along the bottom of the crevasse, once more on their way to their unknown destination.
Very soon after this it was discovered that the waters were subsiding much more rapidly than could be accounted for by the volume that escaped through the subterranean channel. It was therefore necessary to conclude that there must have been some convulsion in another part of the mountains which had opened a fresh channel from the lake to the outer world.
The next step was to raise the two inner of the three doors which guarded the entrance to the caverns. The raising of the first one showed the ice still intact between it and the second, and this had to be broken up and removed before the second could be reached. Then the middle door was raised an inch or so and the water spurted out from beneath it.