"What can you guess about the alien race that built this place?" asked Joe as he ran his hands across a set of tools, picking one up and putting it back down. "What do we know about them?"

"They're humanoid, definitely," replied Mark as he gazed at a rack of instruments. "We've already agreed on that. I a.s.sume that the two figures I saw last night are from the people who constructed this amazing facility. Can't guess why they're not out in force here, unless there are only a few of them aboard. Can't guess why they don't show themselves. Don't know how old this asteroid is or what it is for. But they're definitely humanoid. Even if I hadn't seen them, we could tell that by the shape of the tools and everything else we've seen."

"And the food they gave us is not too different from what we're used to. And think about this: they put fresh fruit in those food packages.

They must have a hydroponic orchard somewhere in this asteroid. There must be a huge portion of this complex that no human has ever seen-and maybe can't get into! This place is big enough to house an entire city.

Maybe there are thousands of them here! George said that he only explored a tiny part of the inhabitable region when he was here.

Everything we've seen tells me that they're a lot like us."

"That might tell us something about the nature of the universe, Joe. I like to wonder about things like that."

"And look, these s.p.a.cecraft have wings. They're not just for travel in the void; they're made for flight on a planet with an atmosphere."

Zip came over the joined the conversation. "If they helped us get from the warehouse area to this hangar, why aren't they helping us get into the s.p.a.ceships?"

"Maybe there're only two of them-the two I saw last night," suggested Mark. "Maybe they're caretakers or something like that, and not s.p.a.cemen. Maybe they don't know much more than we do how to get into these beauties."

"Well, whatever the reason, I guess we're on our own, at least for the time being."

"Looks like some sort of laser here," said Joe, picking up an object that resembled a flashlight. It had two dials on it with signs of calibration, and a b.u.t.ton that was probably intended to activate it.

"If it is a laser, and if these dials move the power from low to high, who knows which end is which?"

"Take it into the power plant and aim it at the floor. An instrument that small can't have too much power and won't hurt a half mile of solid iron. See what happens," suggested Mark.

Joe shrugged. "Okay." He went over to the door through which they had come a half hour before. He was back in a few minutes.

"It's a laser, all right. This dial here changes the intensity of the beam from low to high, and this one-well, watch. There's a barrel of powder over here. Talc.u.m or something." He reached in, took a handful of the dust, and dropped it back into the barrel. A cloud of dust rose up. He activated the laser through it. A bright blue beam appeared. He turned a dial and the beam became a brilliant green.

"Lasers of different frequencies, all in one tool!" Mark exclaimed.

"Yeah, and it's got red too!"

"Lots of possibilities with this," said Zip. "I'll bet it can be used to open the s.p.a.cecraft. The doors can't be only voice-activated, or they couldn't open the door in a vacuum. What else is there? Heat, magnetism, light? They used heat, body heat, on the panel back in the room where we were kept prisoner. Heat won't work in deep s.p.a.ce. Let's try light. We've got the tool here."

The Starmen went back over to the s.p.a.cecraft. Joe set the laser for blue light and ran the beam over the surface of the ship. For several minutes he tried various colors and intensities. When he set the laser for yellow light, there was a change in the surface of the ship.

"Ah!" said all three Starmen at once. The outline of a door appeared, with markings in several places. Joe experimented a little more, placing different intensities on the markings. In a moment he was rewarded. The door recessed a few inches into the ship, and slid aside with quiet efficiency. Joe immediately stepped through the portal.

The furnishings of the alien s.p.a.cecraft were similar to what the Starmen were familiar with, but the control panel was more challenging.

Some controls were obvious, since they were necessary for any s.p.a.cecraft; others were completely unfamiliar.

After about an hour of looking around, Joe sighed, "Gonna need more time, Zip."

"I know. We'll just have to dedicate ourselves to it until we feel confident enough to take the ship into s.p.a.ce."

"I'm making some progress here," announced Mark. He was at a side panel near the navigation station. As he worked the keyboard, various schemata appeared in quick sequence. "I can't read anything, but it's obvious that these are engines. I can't recognize everything that's coming up, but most of it I can. See, here is a circuit diagram, and this part here can only be a reaction chamber. I think this ship might use cold fusion for power, but I can't know for sure until I can read this stuff, or see it in action."

"You figure it out, Mark, and I'll fly it," said Joe confidently.

"Well, this stuff is you boys' specialty," said Zip. "I've got to think ahead to the next problem. a.s.suming we can get this rig to fly, and a.s.suming we can open the airlock, we've still got to escape the pirates. I doubt this ship is one of the invisible ones, and they'll have us spotted and speared in less then three minutes if we just fly out of here, saying, 'Thanks for the hospitality, sorry we have to leave so soon.'"

"You can figure it out, Zip! We'll get this grand machine ready!" Joe was enjoying the challenge. It was hard to keep him down.

After eight hours of work on the s.p.a.cecraft and with dinner behind them, Joe said to Mark, "Let's go back into the power plant and see if we can't find some way to sabotage the system so that the pirates can't find us when we take off. You can bring up some files on those huge screens. Maybe we can even find some way to close down their whole operation."

"Sounds good to me," said Mark, picking up a gla.s.s of water. He took a sip and swished his mouth with it, then swallowed. "Best we can do without toothbrushes, I guess."

"If it were that easy," said Zip, "our hosts would probably have shut down the pirates long before this. After all, it's their plant and they know it better than anyone."

"You've got to be right, Zip, but I don't like sitting around. We've been in this room all day and I'm ready for a break. I really do like that huge plant. Man! Imagine a room ten miles long!"

The three Starmen descended the metal stairs and exited into the enormous plant. A few yards away was one of the large computer terminals. Mark went over to it and activated it.

"I can recognize a few things, now that I've been through so many of the files upstairs," he informed his partners. "This, I think, is the lighting system." He pressed a b.u.t.ton. There was a loud "chunk" sound and the plant lit up brightly.

"Ow!" said the three Starmen and covered their eyes. They were not prepared for the sudden brightness. When they could tolerate the light, they looked above them. Without a word, Mark lay down on his back and just stared upward. Rank after rank of lights went up on the iron framework for nearly a mile. A ceiling the color of charcoal was barely visible, with what looked like rectangular viewports imbedded in it.

Joe and Zip remained standing and looked to their left. The lights blazed for about half a mile. Beyond that point was darkness.

"It will take a lifetime to learn everything there is to know about this place," said Mark dreamily.

"I think we'll be back someday," replied Zip. "What else can you do, Mark?"

Mark got up and turned the lights off. It took nearly a minute for their eyes to adjust to the dimness. While Mark looked through file after file, Joe and Zip wandered through some of the iron latticework.

They climbed spiral staircases for a level or two before descending again, and examined the connections of tubes, pipes, and circuits.

"I've got something!" called out Mark. The others ran to him. He pointed at the screen. "See, this is the main power generator. I can tell because of the coils over here and the way the circuits are connected. There are about eight of these; they must be s.p.a.ced in a row a little over a mile apart. They can operate singly or in combination.

But look! They don't just power the life-support systems-in fact, I haven't found that part at all yet. But these are thrust systems! Do you know what that means? This asteroid is a s.p.a.cecraft! It's made to travel!"

"Can't be!" said Joe, flabbergasted

"It is. Look." Mark flipped past a few more files, pointing out the connections and the diagrams of chambers, coils, and energy field generators. "I'm just barely getting a glance at this stuff, of course, and I don't understand it all, but I have no doubt about what I've seen so far."

"Why don't you look for that life-support file and see if you can turn off the pirates' energy or something?" Joe suggested.

"No, Joe," said Zip. "As I said before, if it were a good idea, our hosts would probably have done it already. I think that whatever they're not doing, we shouldn't try to do. Remember, even St. George didn't want to fiddle with something he didn't understand."

"George is a real nice guy, Zip," said Joe, "but I still think he's breathed a little too much vacuum for his own good. You have to experiment in life, sometimes."

"I want to learn more about this power system! This is amazing!"

rhapsodized Mark. "If I'm right, this b.u.t.ton here will..." He pressed it. Almost at once a stream of paper began to feed out of a slot to the right of the terminal and fell down, sheet by sheet, into a gathering tray. Mark picked up the first sheet.

"It's printing out the diagrams of the thrust system. just like that.

You're right, Joe-this place is great!"