The force of their leap sent them flying through that dozen feet of space to strike the Martian at the moment his tube levelled. One hissing call he uttered as they struck him, and then with all his strength Lanier had grasped the crocodilian body and bent it backward. Something in it snapped, and the Martian collapsed limply. The two looked wildly around. Nothing showed that the Martian's call had been heard, and after a moment's glance that showed the head of the centipede machine already freed, they were clambering up into its control room, closing the door. Randall seized the knob with which he had seen the machines operated. As he pulled it toward him the machine moved across the tunnel opening and raced smoothly over the cavern's floor. As he turned the knob the machine turned swiftly in the same direction. He headed the long mechanism toward one of the upward-curving tunnels which the Martians had blasted larger in descending. They were almost to it when there flashed up into the cavity from one of the downward tunnel openings a centipede-machine, and then another, and another. The Martians in their transparent-windowed control rooms took in at a glance the dead crocodilian on the floor, and then the three great machines were darting toward that of Randall and Lanier. "The Martian we killed!" Randall cried. "They heard his call and are coming after us!" "Turn to the wall!" Lanier shouted to him. "I have the rays--" * * * * * At that moment there was a clicking beside Randall and he glimpsed Lanier pulling forth two small grips he had found, then saw that two crimson rays were stabbing from tubes in their machine's front toward the others even as their own rays darted back. The beams that had been loosed toward them grazed past them as Randall whirled their machine to the wall, and he saw one of the three attacking mechanisms vanish as Lanier's beams struck it. Around--back--with instinctive, lightninglike motions he whirled their centipede-machine in the great dim-lit cave as the two remaining ones leapt again to the attack. Their rays shot right and left to catch the two men's vehicle in a trap of death, and as Randall swung their own mechanism straight ahead he glimpsed at the cavern's far end the great earthen worm god still upreared. On either side of them the red beams burned as they leapt forward, but as though running a gauntlet of death Randall kept the machine racing forward in the succeeding second until the two others loomed on either side of it. Then Lanier's beams were driving in turn to right and left of them and the two vanished as though by magic as they were struck. "Up to the surface!" Lanier cried, his eyes on the glowing dial of his wrist-watch. "We've been held hours here--we've but a half-hour or more before earth midnight!" * * * * *