"The pressure-chamber door-slide was closed. I knew the mechanism of these exit-portes. There were four of them in the hull-bottom of the _Seven Stars_--two on each side. There was an inner door-slide; a sealed pressure-room some ten feet square and six feet high; and an outer door-slide. Ordinarily the mechanism was automatic. The outer slide must be closed if the inner one was open. To make an exit, one went into the pressure-room; closed the catwalk door, and with manual control slowly opened the outer slide, so that the air in the sealed room would hiss out into space. After which, with a thirty-second interval, the outer slide would close and the inner one slowly open, admitting the ship's air again into the pressure-room. "Someone worked the manual controls wrong!" Kellogg was muttering. He gestured to where there was a duplicate set of controls out here in the corridor. "That outer slide opened too quickly!" We could hear the last of the air rushing out with a wild gush. A stab of horror went into my heart. Brenda Carson in there, trying to escape from the ship--not knowing how to work the controls--opening that outer slide too quickly. The air in the pressure-room was gone in a few seconds. Then we heard the click of the outer slide closing. The inner door began very slowly opening. With a muttered curse of impatience Kellogg twitched at the control levers here. The inner door slid wide. We clutched at the catwalk rail to hold ourselves against the gust of wind as the little pressure-room filled. And then we rushed into it. Pressure suits, powered as I knew by tiny gravity-repulsers and a rocket-stream mechanism, stood here in racks. One of them lay here on the floor, entangled with a rack-post so that it had not blown out. Brenda evidently had tried to get into it and failed. "Look! Good Lord--poor little thing--" Kellogg murmured. He had slid aside a tiny bull's-eye shade. Through it a segment of space outside the hull was visible. We had only a glimpse of a ghastly body, mangled by the explosion of the pressure within itself, out in the pressureless vacuum of space. It floated past us, some forty feet out. Held poised by the gravity, the nearness and bulk of the _Seven Stars_. Horrible little satellite, already finding an orbit of its own, slowly circling around us. * * * * * I staggered back from the bull's-eye. As I rushed back along the catwalk my horrified mind was clamoring with the vague thought: had Brenda operated that pressure-mechanism wrongly? Or had someone on the catwalk, at the controls there, done it? That thought, too, was stricken away. I reached the forward deck triangle. The bow-peak lookout was calling up to Captain Wilkes: "Passenger overboard! Brenda Carson! It's Miss Brenda Carson!" Dead girl in the space-light. I could not look at the horrible thing as it rounded our bow and came slowly floating past again. "You, Fanning--what's happened? Brenda Carson, he says."