Dr. Manschoff beamed down at him from the top of the river bank. "Don't be alarmed," he said. "I wasn't following you with any intent to eavesdrop. I was merely concerned about him." His eyes flickered as he directed his gaze past Harry's shoulder, and Harry turned again to look at Arnold Ritchie. * * * * * The little man was no longer standing and he was no longer alone. Two attendants now supported him, one on either side, and Ritchie himself sagged against their grip with eyes closed. A hypodermic needle in one attendant's hand indicated the reason for Ritchie's sudden collapse. "Merely a heavy sedative," Dr. Manschoff murmured. "We came prepared, in expectation of just such an emergency." He nodded at his companions. "Better take him back now," he said. "I'll look in on him this evening, when he comes out of it." "Sorry about all this," Manschoff continued, sitting down next to Harry as the orderlies lifted Ritchie's inert form and carried him up the slanting slope. "It's entirely my fault. I misjudged my patient--never should have permitted him such a degree of freedom. Obviously, he's not ready for it yet. I do hope he didn't upset you in any way." "No. He seemed quite"--Harry hesitated, then went on hastily--"logical." "Indeed he is." Dr. Manschoff smiled. "Paranoid delusions, as they used to call them, can often be rationalized most convincingly. And from what little I heard, he was doing an excellent job, wasn't he?" "Well--" "I know." A slight sigh erased the smile. "Leffingwell and I are mad scientists, conducting biological experiments on human guinea pigs. We've assembled patients for breeding purposes and the government is secretly subsidizing us. Also, we incinerate our victims--again, with full governmental permission. All very logical, isn't it?" "I didn't mean that," Harry told him. "It's just that he said Sue was pregnant and he was hinting things." "Said?" Manschoff stood up. "_Hinted?_ I'm surprised he didn't go further than that. Just today, we discovered he'd been using the office facilities--he had a sort of probationary position, as you may have guessed, helping out the staff in administration--to provide tangible proof of his artistic creations. He was writing out 'official reports' and then photostating them. Apparently he intended to circulate the results as 'evidence' to support his delusions. Look, here's a sample." Dr. Manschoff passed a square of glossy paper to Harry, who scanned it quickly. It was another laboratory report similar to the one Ritchie had shown him, but containing a different set of names. "No telling how long this sort of thing has been going on," Manschoff said. "He may have made dozens. Naturally, the moment we discovered it, we realized prompt action was necessary. He'll need special attention." "But what's wrong with him?"