He sprinted ahead now, noiselessly. The scavengers squealed in renewed fury, racing along beside him. Once he stumbled, felt a horrid mass of the things swarming. But he fought his way up. By the time he reached the light, he was sure he had gained a considerable distance on his pursuer. He hurried around the bend, saw that the faint light came from a radium lamp in the ceiling. It had probably been there for years. But what held his attention, and brought him to a standstill, was the figure huddling against the wall. It was an Earthman and he was still alive. His clothes were in shreds and the rats had been at him--before he reached this light where the rats did not come. He struggled up weakly, gazed at Ketrik out of idiotic eyes. Ketrik hurried forward, pulled the man erect. One look into his gibbering face, and Ketrik felt his stomach turn over in a prodigious yawn. _It had taken more than the rats and darkness to do this! The Earthman's mind had been literally and deliberately blasted!_ Ketrik suddenly remembered what Mark had said of Dr. Ransome, whom they'd found drifting near the moon ... his mind that of a week-old infant.... He hurriedly searched the man's clothes, but found nothing. He knew this must be one of the operatives whom Mark had sent a month before--E-39 or EV-5. The other must be dead, somewhere in this tunnel or back at their communications base in the mountains. He spoke softly to the man, but the other only cringed in terror. Then, with unexpected strength, he tore himself from Ketrik's grasp and was scuttling away, back around the bend of the corridor. Ketrik followed, called a warning. He reached the bend too late. He heard the hiss of a heat-gun and saw the vivid blue streak of it from out of the darkness--a streak that touched the Earthman's chest and sent him crumpling. Ketrik fired at the spot where the ray had appeared, fired instinctively but unerringly. He heard a soft moan that ended abruptly, then a clatter of sound. He moved slowly forward, hugging the wall. He feared a trick. Past the little radius of light where the Earthman's body lay, he stumbled upon the Martian Special. He flashed his electro again and saw that the man was unmistakably dead. He went back to the Earthman, stared down for a moment. There was no doubt that he had unwittingly saved Ketrik's life. "Guess you served your purpose here, after all," Ketrik murmured, but his thoughts at that moment were not as calloused as the words. With a few strokes of his electro, he removed the crystyte globe of radium from the ceiling; and carrying this light, he was no longer bothered by the scavengers. For hours he proceeded along the tunnel. At last, infinitely weary and wracked with pain, he reached a blank wall. Searching around it, he at last found a loose stone which he pulled away. A tiny metal lever was revealed. After tugging interminably at it and pounding the rust away, Ketrik managed to pull it slowly back.