The lift halted at the muster deck and the door slid open. "So here's what we'll do," said Pritchard as they stepped off. The old man heard him out and then nodded slowly, his rheumy eyes narrowing. They waited while the men arrived, the whole ship's company of twenty cadet hunters (less McManus, now) and five crewmen. They all stood around eyeing Pritchard and the captain. The air was heavy with that lurking stench, but it was not too thick here to be unbreathable. As soon as the gas mask detail had shoved the last of the cartons off the lift Pritchard started for the controls. The muster deck was a heavily insulated circular chamber a bit forward from amidships. The entire ship could be controlled from there. In emergencies it could be detached from the ship and used as a temporary space raft, having all necessary supplies in its padded wall lockers. "First," announced Pritchard, "we're going to button this ship up tight." He reached for the ventilator switch and flicked it on. Little motors all over the inner and outer hulls began wheeling shut the valves that closed the six-inch holes that were the ventilating system's intake and exhaust ports. In a matter of seconds the _Apollo_ would stop breathing the wine-like night air of Thisbe II. On the wall above the switch little green lights began to blink off one by one. As if gradually understanding his strategy, the men began to move up behind Pritchard, their eyes on the bank of fiery green points winking out. The last little gem flickered, died, and then, strangely, flamed up again. And, just as it went out for good, the entire muster deck gave a lurch. Feet scuffled, slipped, staggered. Here and there a body thudded to the steel plates of the floor. Pritchard's voice rose thundering above the abrupt commotion. "Grab hold! Something's got the ship--something--" The muster deck swung in a wild circle, men sliding helplessly, caroming off the walls. Pritchard's flailing hand caught something and his long bony fingers laced about it in a grip of steel. In benumbed fascination, he saw his body lengthen out, straining against that grip, appearing to levitate from the deck. The whole chamber tilted slowly until it seemed to hang below him. Men were slipping and falling down into the curved well of its farther wall, but some had grabbed out at holds here and there--a door-pull, or a stanchion, and dangled like Pritchard. At the last instant he understood that the _Apollo_ was falling. He had just time to pull himself up, to give his arm some play against the shock to come-- The great pointed cylinder struck with an awesome, deafening clangor--fell with a single bounce across its landing burn and settled to roll over approximately one-third its circumference.