Choking, Rik went to the center of the high room and looked into the horizontal face of the clock. The broad indicator arm was at its utmost numeral, and was pocked with rust. They'd lain here beyond the time-of-awakening by at least four times the years they'd planned!
"It can't be right," Rik gasped, his brain reeling for want of clean, cool air. "The mechanism has failed somehow." Afraid to think about it, he tilted the clock up on its base until the pedestal which supported it lay on its side upon the floor. The square block of metal that based the pedestal was now uptilted beyond the vertical, exposing a gaping trap in the floor. Rik did not like the tarnished look of the metal underside of the pedestal-base, forged of an alloy supposed to be incorruptible. A sick thought took hold of his insides then, as he placed one foot upon the rocky staircase under the floor. The clock-indicator had halted at its utmost numeral.
But what if they'd lain here even longer than that? There would be no way of knowing. No way at all.
He descended the staircase swiftly then, glad at least that the air was better down in the pump chamber. "It would be, of course," he reminded himself, "if the pump went off, even. This air would never be circulated, never have its chance to become corrupt with our exhalations." And then his musing was halted in midthought as he came upon the pump. Or upon what had been the pump.
Where rigid cylinders of gleaming metal had been, a few jagged teeth of brown corruption lay in a circle. The pistons were no better, though their thickness had preserved more of their original shape despite the inroads of age, so they could be recognized for what they were—had been. The central shaft was a long mound of flaking dust on the floor between the path of the pistons, and the wall-sized mass of the filters—woven of metal and powerful synthetic fibers—crumbled beneath the pressure of his finger.
He sought and found the ponderous casing in which the engine-empowering radioactive element had lain, and its thick walls tore away like wood pulp in his hands. The element, when he found it, was already become cold grey lead. And it had had a half-life of centuries....
Rik crumpled slowly to the floor, shutting his eyes, trying not to think of the eons which must have passed while they all lay sleeping the pseudodeath in the vaults. What might the world have become in the interim!
A current of cool air suddenly touched his face. His head came up instantly, his eyes seeking the source.
A feathery motion of torn edges in the filter showed him that it came through the gap he had torn there. Rik sprang to his feet then, leaped at the filter and tore out chunks by the armful, letting the pulverized material float in spinning clouds of dust motes behind him. The air grew stronger, came faster, as he ripped away the corruption, and then he could see the tunnel beyond.