Charley remembered something about a molecular lattice, but it didn't make any sense to him, and was only a puzzle. But the professor told him all about the technique, in a very earnest and scientific voice that was convincing to listen to, and showed him mice that he'd cut the tails off of, and the mice had brand-new tails, and even feet in one or two cases. There were a whole lot of small animals in cages, all together in back of the professor's tent, and Charley looked at all of them. The professor had a flashlight, and everything was very clear and bright. When the demonstration was over, Charley had no doubts at all. It was obvious to him that the professor could do just what he said he could do: grow limbs on things. Charley scratched his head with his left foot, nervously. "That's why I came to you," the professor said. "I need a human being--just to show the scientific world that my technique works on human beings. And I've worked with you for a number of years now, Charley." "Five," Charley said. "Five since you came with Wrout." "I like you," the professor said. "I want to make you the first, the very first, person to be helped by my technique." Charley shifted his feet. "You mean you want to give me arms," he said. "That's right," the professor said. "No," Charley said. * * * * * Professor Lightning nodded. "Now, then," he said. "We'll get right to work on ... Charley, my boy, what did you say?" Charley licked his lips. "I said no," he said. Professor Lightning waited a long minute. "You mean you don't believe me," he said at last. "You think I'm some sort of a crackpot." "Not at all," Charley said politely. "I guess if you say you can do this ... well, I see all the animals, and everything, and I guess you can do it. That's O.K." "But you're doubtful," Professor Lightning said. Charley shook his head. "No," he said. "You can do it, all right. I guess I'm sure of that, professor." [Illustration] "Then," the professor said, in a tenser voice, "you think it might be dangerous. You think you might be hurt, or that things might not work out right, or--" "Gee," Charley said, "I never thought of anything like that, professor. I know you wouldn't want to hurt me." "I certainly wouldn't," Professor Lightning said. "I want to help you. I want to make you normal. Like everybody else." "Sure," Charley said uncomfortably. "Then you'll do it," Professor Lightning said. "I knew you would, Charley. It's a great opportunity. And I offered it to you because you--" "Gee, I know," Charley said, feeling more uncomfortable than ever. "And don't think I don't appreciate it. But look at it my way, professor." He paused. "Suppose I had two arms--just like everybody else, the way you tell me. What would happen to me?"