Here the Minister for Health rapped on a door and ushered Calhoun through it. They entered a huge room filled with the complex of desks, cameras, and observing and recording instruments that the study of a living organism requires. The setup for study of dead things is quite different. Here, halfway down the room's length, there was a massive sheet of glass that divided the apartment into two. On the far side of the glass there was, obviously, an aseptic environment room now being used as an isolation chamber. A man paced up and down beyond the glass. Calhoun knew he must be a para because he was cut off in idea and in fact from normal humanity. The air supplied to him could be heated almost white-hot and then chilled before being introduced into the aseptic chamber for him to breath, if such a thing was desired. Or the air removed could be made incandescent so no possible germ or its spores could get out. Wastes removed would be destroyed by passage through a carbon arc after innumerable previous sterilizing processes. In such rooms, centuries before, plants had been grown from antiseptic-soaked seeds and chicks hatched from germ-free eggs, and even small animals delivered by aseptic Caesarean section to live in an environment in which there was no living microorganism. From rooms like this men had first learned that some types of bacteria outside the human body were essential to human health. But this man was not a volunteer for such research. He paced up and down, his hands clenching and unclenching. When Calhoun and the Minister for Health entered the outer room, he glared at them. He cursed them, though inaudibly because of the sheet of glass. He hated them hideously because they were not as he was; because they were not imprisoned behind thick glass walls through which his every action and almost his every thought could be watched. But there was more to his hatred than that. In the midst of fury so great that his face seemed almost purple, he suddenly yawned uncontrollably. Calhoun blinked and stared. The man behind the glass wall yawned again and again. He was helpless to stop it. If such a thing could be, he was in a paroxysm of yawning, though his eyes glared and he beat his fists together. The muscles controlling the act of yawning worked independently of the rage that should have made yawning impossible. And he was ashamed, and he was infuriated, and he yawned more violently than seemed possible. "A man's been known to dislocate his jaw, yawning like that," said Calhoun detachedly. A bland voice spoke behind him. "But if this man's jaw is dislocated, no one can help him. He is a para. We cannot join him." * * * * *