The two heard great thumping sounds from above, saw the tunnels leading from above becoming suddenly many times greater in size as red rays flashed down along them to gouge the tunnel's walls. Then down from those enlarged tunnels there were bursting long shining shapes, great centipede-machines crawling down the tunnels which their rays made larger before them! And as the centipede-machines burst down into the cavern their crimson rays stabbed right and left to cut paths of annihilation among the worms. "The Martians!" Lanier cried. "They didn't find us above--they knew we must have been taken by these things--and they've come down after us!" * * * * * "Back, Lanier!" Randall shouted. "Quick, before they see us, behind this--" As he spoke he was jerking Lanier with him behind the looming earthen statue of the great worm god. Crouched there between the statue and the cave's wall they were hidden precariously from the view of those in the cavern. And now that cavern had become a scene of horror unthinkable as the centipede-machines pouring down into it blasted the frantically crawling worm monsters with their rays. The worm monsters attempted no resistance, but sought only to escape into their downward tunnels, and in moments those not caught by the rays had vanished in the openings. But the centipede-machines, after racing swiftly around the cavity, were following them, were going down into those downward tunnels also, their rays blasting down ahead of each to make the tunnel large enough for them to follow. In a moment all but one had vanished down into the openings, the remaining one having its front or head jammed in one of the openings from the failure of its operator to blast a large enough opening before him. As Lanier and Randall watched tensely they saw the machine's control room door open and a Martian descend. He inspected the tunnel opening in which his vehicle was jammed, then with a hand ray-tube began to disintegrate the earth around that opening to free his machine. Randall clutched his companion's arm. "That machine!" he whispered. "If we could capture it, it would give us a chance to get back to the city--to Milton and the matter-transmitter!" Lanier started, then nodded swiftly. "We'll chance it," he whispered. "For our twenty-four hours here must be almost up." * * * * * They hesitated a moment, then crept forward from behind the great earthen statue. The Martian had his back to them, his attention on the freeing of his mechanism. Across the dim-lit cavern they crept softly, and were within a dozen feet of the Martian when some sound made him wheel quickly to confront them with the deadly tube. But even as he whirled the two had leaped.