She was pointing to a slender, graceful object that rested in a metal frame over their heads. It was very like an airplane, with short, stubby wings. But instead of propellers it had rocket nozzles. Wheels on its bottom, clung to a helical guide rail that spiraled upward inside a great, vertical tube that must find its way to the surface somewhere. Apparently the tube was the inside of the staff held by the golden colossus above. And the staff penetrated the cavern's roof. "Naturally, being as advanced in science as they were, those old people would keep something to get about with, wouldn't they?" Troubles questioned, as she climbed up the ladder to the craft's cabin entrance. * * * * * Opening the door was a difficult thing; but Perry bounded up the rungs and was helping her. He was ready to take his chances too, in spite of his talk. The door opened under the hammering pressure of his calloused palm. There was space inside for two or three people to lie prone. The controls were not unfamiliar. There was a joystick, and a second lever which must take the place of rudder pedals. Perry was wiggling, the control. They were stiff but not immovable. With an eye of a practiced airman, he noted what they did to the tail and wing fins. So far, so good. He turned a small valve on the dash. There was a creaky, rhythmic sputter from behind. Evidently there was still fuel in the tanks. In response to the brief rocket thrust, the craft rolled a little way up the spiral guide rail. Then back to norm as Perry returned the throttle to its original position. "So what?" he said with a shrug. "Nothing funny about finding this crate here. It's made of the same kind of evidently almost uncorrodable metals as the instruments here in the control room. So it should last forever. And the old-timers must have longed for the great outdoors sometimes. That's logical enough. But there isn't the sign of a weapon--nothing we could use to attack a giant. And Kerwin is a giant, now, in relation to us!" "How about bluff?" Troubles questioned, dimples of exasperation showing at the corners of her mouth. "Come on, bonehead. Quit stalling! Haven't you got any imagination at all?" Wilcox grinned at her, startled and admiring. Her attitude gave him a lifting sense of adventure. "Okay!" he drawled. "Funny, though--I used to think you were a friend of Kerwin's. Of course, you could be trying to pull a fast one yet, I suppose!" "And I could knock that pug schnozzle of yours flatter than it is, for that crack!" Troubles returned. "Come on! Let's see action--if you're good enough to get any out of this thing!" Perry opened the throttle. A little at first, then more and more. Speed was built up. It became a dizzy whirl. Around and around that spiral track, up and up.... * * * * *