“I’m afraid there is, Doctor,” pointed out Estnerdole. “You can’t get into the tank. It’s lying on its right side, with the door underneath. Unless there is some outside connection you can reach to replenish the oxygen in your armor, you are rather limited in your supply.” The man was silent for several seconds, except for a brief muttering which the students could not make out clearly. “You’re right, Es,” he said at last. “It is an emergency after all, for me. Do you suppose you people are strong enough to turn the tank right side up?” The Mesklinites were somewhat doubtful, but clustered around to try. LaVerne, who shared the exaggerated idea of Mesklinite physical strength which was so common among human beings, was not surprised when the vehicle stirred under their efforts; indeed, he was disappointed when it lofted only a few millimeters. After some seconds it settled back where it had been, and one of the students reappeared from the narrow space underneath. “We can move it, but that’s all. We’d have to get this side up several body lengths before it would rock over the right way, and there’s nothing to stand on.” Destigmet wriggled into view behind the speaker. “I can think of only two things to do, and you’ve already suggested one of them,” he said. “The first is for someone to start climbing again. The other is for us to lift the tank once more, while you pack snow under it to hold it up and let us get a fresh purchase. Maybe we can work it up that way before you run out of air.”
“All right,” agreed LaVerne. “It would be better if I had something to serve as a shovel, but let’s get at it. I’m using oxygen just standing here worrying.” For a while it looked possible, if not really hopeful. Carrying the dusty snow in his armored hands proved impractical, but he found that he could do fairly well pushing a mass of it ahead of him as he crawled — and crawling was far easier than trying to walk. Essentially, he was sweeping rather than carrying. He managed to get what would have been several shovelfuls, if he had had a shovel, against the space at the edge of the tank where the Mesklinites had disappeared once more. At his call they strained upward again, and as quickly as he could he pushed the material into the widening space. “That’s all,” he reported when he had done his best, and the students relaxed again. So did the pile of snow. LaVerne, optimistic by nature, felt sure that the tank had not settled quite back to its original position, and kept trying; but after an hour which left him more exhausted than he had ever felt in his three Earth years on Mesklin, he had to admit that the idea was qualitatively sound but quantitatively inadequate. During those days, the student who was trying to climb the slope had made little progress. Once he had gotten nearly a third of the way before sliding most of the way back in a smother of white dust; four or five times he had lost the fight in the first yard or two. The rest of his attempts came between those limits. But it finally became evident that the man’s air was not going to be the real limiting factor. Destigmet pointed out another one to him. “Some time ago, Doctor, one of your fellows taught us about a fact he claimed was very basic — the Law of Conservation of Energy. If I have the terminology right, we can apply very large forces by your standards, but as that law should tell you, there is a limit to the amount of work we can do without food. None of us expected to need food in this class, and we brought none with us.” One of the others cut in. “Won’t people from the College start looking for us anyway? This class should have been over days ago.” LaVerne frowned invisibly behind the blood-stained face plate, which he had no means of cleaning. “They’ll be looking, but finding us will be another story,” he said. “They’d expect to see the tank miles away on the smooth surface of the peninsula. When they don’t, they’ll think we got swept into the sea, or went off to the forest country for some reason. They won’t look over this area closely enough to find the hole we left, I suspect. It’s possible we’ll get out of this with their help, but don’t count on it.” Estnerdole suddenly became excited. “Why not build a tower we can climb, with the water ice from the cliff? We can chip it out easily enough without tools, or even melt it out with the snow — no, that wouldn’t leave us any to work with, but—” His voice trailed off as more difficulties became apparent to him. LaVerne was pessimistic, too, after the just-completed practical demonstration of how much material would be needed even to prop up the tank. Then he brightened. “We could use the ice to get this machine upright — big chunks of it would be more practical and easier to move than the snow. Of course, even that doesn’t get us any closer to getting out of here; the tank certainly isn’t going to climb this sandhill even if I get into it. If only—” He paused, and the ensuing silence stretched out for long seconds. Even with the man hidden in his armor, the listeners got the impression that something had happened. Then he spoke again, and his tone confirmed the suspicion. “Thanks, Es. That does it. Start digging ice, gentlemen. We’ll be out of here in a couple of hours!” Actually, it took less than three days.