The solid stone quivered like jelly. "I got it," said Andy, awe in his voice. "Their blaster. A pellet exploded when the spring hit it, and that set off the magazine." He hesitated, then continued. "There's not ... enough left for identification purposes." The girl was crying. "Anyhow ... you didn't murder them," she sobbed. "And I'm glad--you didn't." "So am I, kind of. We got maybe a week or two to be glad in. We have a few condensed food tablets in my pack. Everything else is back at camp. The tablets will last a little while...." He could hear the girl crying softly, but the closing of the entrance had shut off the last gleam of light from the cave, and he couldn't see her. Awkwardly he reached out in the darkness, found her, drew her gently to him. For a long time there was silence broken only by an occasional soft whisper of sound as one or the other changed his position. Andy realized that he was a little thirsty, and he wondered if this was the forerunner of the violent pangs to come. He was aware of her soft whisper. "Sh--Look--" A spot of weirdly glowing light was moving slowly along the cavern floor. Without body, or visible means of locomotion, it seemed to flow along. Andy felt his hair rising as he looked at it. "Give me your heat-gun," he whispered, and the weapon was passed over to him. He lined up the sights and waited. * * * * * The small spectral figure slowly approached. It hesitated, moved back, then came forward again. Andy forgot that he was thirsty, that he would soon be hungry, that he was doomed to die. He could hear the girl breathing hard. What was the glowing figure? Was it friendly. He did not know, did not dare to guess. Perhaps it was seeking them, perhaps it recognized food in them. Perhaps it was some form of electrical energy, perhaps it resembled jelly, like the blobs that existed on Callisto that were so avid for human flesh. Andy held the sights of the heat gun on it, waited. He did not know whether the gun would affect it. The girl was breathing in long, slow pants, like she was holding her breath. It came nearer, shining like a gigantic fire-fly except that the glow was pale blue instead of golden. It was within twenty feet of them. "Shoot!" Frieda whimpered. "Shoot, quickly...." He started to squeeze the trigger. "Boss," a familiar but unhappy voice spoke. "Something is wrong with me. I shine." "Oscar!" Andy shouted dropping his gun. "You imp! Where in hell have you been?" The glowing spot bounded forward, leaped into Andy's arms. "Do something for me, Boss. I shine and I don't like it." The girl's laughter sounded silly. "I'll do something for you. I'll buy you a barrel of sugar."