"Down the lining of the hull, outside the passengers' quarters to the upper dirigible projectors," and he led the way down a series of steep steel stairways, through bulkheads and partitions of steel. "One thing I forgot to tell you about--the detectors. They're worked on the same principle as the lights, and are just about as efficient. Instead, of light, though, they send out cones of electromagnetic waves, which set up induced currents in any conductor encountered beyond our own shell. Since all dangerous meteorites have been shown to contain conducting material, that is enough to locate them, for radio finders automatically determine the direction, distance, and magnitude of the disturbance, and swing a light on it. That was what happened when that light swung toward us, back there in the prow." "Are there any of those life-boats, that I've heard discussed so much lately, near here?" asked the girl. "Lots of 'em--here's one right here," and at the next landing he opened a vacuum-insulated steel door, snapped on a light, and waved his hand. "You can't see much of it from here, but it's a complete space-ship in itself, capable of maintaining a dozen or fifteen persons during a two-weeks' cruise in space." "Why isn't it a good idea to retain them? Accidents are still possible, are they not?" "Of course, and there is no question of doing away with them entirely. Modern ships, however, have only enough of them to take care of the largest number of persons ever to be carried by the vessel." "Has the _Arcturus_ more than she needs?" "I'll say she has, and more of everything else, except room for pay-load." "I've heard them talking about junking her. I think it's a shame."