knocked all the breath out of his body—but he was unhurt. The lesser gravity had saved him from mortal injury and chance had thrown him on top of the subsidence instead of underneath it. He lay still in an abyss of dark, quivering, listening.
There was only one sound. Tick—tock. Tick—tock.
THEN it had failed. The mechanism was still working! Scrambling to his feet Cliff pulled his torch from his belt and tested it gingerly. It flickered for a moment then steadied. He flashed the beam round on an incredible vision of chaos. The explosion had blown the roof out of the cavern, buried several of the smaller balls under a mountain of debris. Equipment, particularly the rubbish magnetizers that had been on the upper levels, had tumbled down here, undamaged thanks to their massively strong casings. Of Townshend and Val there was no sign. They were somewhere amidst all this with the life crushed out of them.
Cliff's gaze swung to the giant ball. It was smoky black from the explosion, but otherwise untouched and unbudged. The solemn ticking was like a knife to Cliff's nerves. He looked round him desperately, trying to imagine how much time there was left. Now the x-ray machines had been smashed in the upheaval he had no means of seeing where the indicator had reached.
With a thud he sat down, trying frantically to think of a last possible way. His own life didn't matter now: it was Earth that counted, with its millions of unsuspecting souls. In the gloom and the dark of those moments the mechanism was his only company.
Tick—tock. Tick—tock. And each move bringing nearer the consumation of a posthumous plot to destroy and avenge.
CHAPTER VI
Alone—with Ticking Death
TICK-tock. Tick-tock. Tick-tock.
As Cliff sat there, each swing of the giant pendulum grew more inexorable, its ticking growing in the utter silence of a dead planet's interior until it became a thundering vibration that pounded in his ears like the measured tread of Death himself.
Tick-tock! Tick-tock! TICK-TOCK!
Cliff leaped to his feet, his brain reeling.
"No!" he shouted. "By the gods, no!"
Furiously he rushed at the giant ball, beat against it with his fists as though the physical contact would relieve the terrific pressure that was building up inside him; a pressure that bade fair to equal the awful potentiality that was stored up in that sphere of destruction. He backed away with a sob, fingers bleeding, and tore his ray gun from his holster.
He held it on the ball until its charge was exhausted; then he hurled the useless tool at it.
The gun rang against the immutable metal, clattered away into the shadows of the cavern.
Silence fell again, except for the sound of the pendulum, measured, undisturbed, grimly purposeful.
TICK-TOCK! TICK-TOCK!
Cliff stared about, through the gloom.
"Science," he muttered. "An incredible, diabolic science. These Martians knew too much."
He moved about among the tumbled rubbish of the explosion, braving the possibility of still further hidden devices of sudden death stabbing burning horror down upon him from the darkness.
"Thousands of years ago they all
