"So am I," Rick put in. "I'm thinking of the breech-ends of these same tubes down below. And of an ordinary Fourth-of-July pinwheel made to spin by the tangential reaction of the gases of old fashioned gunpowder. And of what that screwball, Fane, muttered to himself. 'Give back a world.' Yeah. What was it that killed Mercury as a reasonably habitable planet?" "I see what you mean," Finden growled. "Mercury stopped rotating. But about the rest you're absolutely nuts." "Are we?" Lattimer challenged. "Does making a world rotate again, seem too big a job for a bank of atomic jets the size of these aimed just above the horizon? Those old Martians could have done it. And maybe our people could, too, allowing years of work and vast expenditure." At that moment Rick Mills understood Frank Fane as never before. "So this is supposed to be Fane's glory," Finden mused hoarsely, his eyes wide. "To give a ruined world back to civilization. Restore it. Not bad for an unknown pug-ugly even if the bug in his head says he has to kill everybody around and blame it on old war machines running amok by themselves so that there will be no division of triumph; so that, with all of us dopes dead, he'll look even bigger." Lattimer's lips twisted. They were about to utter curses. But then, beyond the window, there was a dazzling flare of light. The men didn't ask what kind of missile had been launched against them. That they fairly tumbled down the spiral was all that saved their lives. The terrible roar of sound itself seemed enough to kill. Automatic portals clanged above them to shut off the outrush of air and the influx of vaporized metal and radioactivity. "We've got to block all entrances to the jet room!" Rick shrieked. "And we've got to see that there are no tin soldiers running around loose. Then...." Rick's voice trailed away. With the blaster that had been Fane's, Lattimer brought down tunnel-roofs, barricading himself and his companions in the hall where the bases of the tubes were, behind tons of wreckage. It might help. * * * * * "Fane will try to dig us out, but now it should take a little time, I hope," Rick said. "We're buried deep in rock and snow and congealed atmosphere. And he probably hasn't enough war engines assembled around here to really try to blast through to us." "So what do we do?" Finden demanded. "Look around to see what we _can_ do," Lattimer shot back at him. They went down the row of great jet-tubes. To Rick's and Lattimer's trained eyes basic principles of function of these jets were not too hard to trace out. Regardless of what monsters on what world invented a thing, natural law remained the same. And so the shaping of metal and the directing of forces in any device had to remain the same everywhere.