Jack and Mark were deeply impressed by the good sense of the professor's observations; and both Andy and Roebach were disturbed. They watched the disintegration of the ice with considerable worriment. It seemed to melt away much quicker during these hours of sunshine than it had on the previous occasion when the orb of day shone fully upon the surface of the island in the air. The soil they had camped upon began to crumble away, too, for the heat was insidiously melting the ice under the morainial deposit. At the time which should be high noon--when the sun was directly overhead in its course--one end of the patch of soil, forest and all, slumped into the water with a loud crash, and at once the fierce current tore the rubbish apart and carried it onward to the brink of the crevasse, into the maw of which it fell. "Wash is perfectly right in his statement," Jack Darrow said. "This is no place for any of us. As soon as the ice freezes up after the sun sets we must travel as fast as we can after the wolves." "And I wish we could travel as fast as they can," muttered Andy Sudds. "I wish we had Mr. Roebach's dogs and sleds," said Mark. "All right. As long as you're wishing, though, why not wish for the right thing?" demanded Jack. "And what is that, Master Jack?" asked the oil man. "Wish we were aboard the _Snowbird_ and that she was all right. That's what _I_ wish." "And I reckon the boy's right," said Phineas Roebach, with a sigh. "As much as I object to flying through the air, an airship now would be a God-send indeed." What bear meat the wolves had not destroyed the water now washed away. The party had only that which Andy had smoked over the fire. But this was easily carried and their packs were not heavy when they prepared to leave the camp as soon after sunset as the frost would allow. The terrific change from the heat of midsummer to the cold of midwinter, and all within something near twenty-four hours, was hard indeed to bear. The professor calculated that the drop in temperature from high noon was, two hours after sunset, exactly seventy degrees Fahrenheit. "Human life will become extinct upon this fragmentary planet, if nothing further happens to it, in a very few years," he said, thoughtfully. "We are not attuned to such frightful changes." They had eaten, and had packed their supplies. The earth had long since appeared again and the radiance she reflected fell softly upon the ice-field. It glistened like silver, stretching, miles and miles away before them when they climbed down from the fringe of trees in which they had encamped, and set out down the glacier.