At about the ventilators?" "Take us days to remove all the screens and purifiers," said Hoskins, "and then we'd be up against the intake ports. You could stroll out through any of them about as far as your forearm. And after that it's hull-metal, skipper. _That_ you don't cut, not with a piece of the Sun's core." The Captain got up and began pacing, slowly and steadily, as if the problem could be trodden out like ripe grapes. He closed his eyes and said, "I've been circling around that idea for thirty minutes now. Look: the hull can't be cut because it is built so it can't fail. It doesn't fail. The port controls were also built so they wouldn't fail. They do fail. The thing that keeps us in stays in shape. The thing that lets us out goes bad. Effect: we stay inside. Cause: something that wants us to stay inside." "Oh," said Johnny clearly. They looked at him. He raised his head, stiffened his spine against the bulkhead. Paresi smiled at him. "Sure, Johnny. The machine didn't fail. It was--controlled. It's all right." Then he turne