She held up a little round satchel. It was exactly like the cases that people used in his country for carrying bowling b.a.l.l.s. Odin was puzzled.

And he a.s.sured himself that he would never understand women. Why would the girl be carrying a bowling ball with her into outer s.p.a.ce?

Odin joined Wolden, Ato, and Gunnar in the "engine" of the b.u.mpy little train. Here were real windows of quartz, and he could see more of the moon's surface as the tractor and its jointed cars wheeled about in a great circle and headed off in the direction from whence it had come.

Once there was a loud _Ping_ upon the roof above them. The tractor shook.

"A meteorite," the driver explained. "They're thick tonight. Don't worry.

There's a screen upon the roof that slows them down and melts 'em. The larger ones never reach us. Some of the tiny ones get through."

They came to a sheer mountain which in the beams of the tractor looked like a silver pyramid painted across a jet-black canvas.

As though answering an unheard vibration, a door opened and they lumbered in. The door closed behind them. For a moment they were in such darkness that even the beam from the tractor seemed alien. Then another door started to open before them and a widening shaft of light was there to greet them.

Odin was thinking that each race must have some craft at which it excels all others. If so, then the building of air-locks was certainly the Brons'

highest art.

Then they advanced into a cavern where five tiny atomic suns were strung out at equal distances upon the ceiling. The cavern was geometrical.

Roughly, it was a mile long, half a mile wide, and half a mile high. The floor was smooth; the walls were sheer. "As though they had been shaped by human hand," Odin thought, but he soon learned that other hands had sheered those walls.

In the very middle of the cavern was a little lake, shaped in the same proportion as the floor. It was surrounded by green gra.s.s, and at one corner was a profusion of water-lilies and cat-tails. There were no trees, but flowers were everywhere. A few small bushes. Here and there were great clumps of vines. Odin guessed them to be wild cuc.u.mber and trumpet vines, for they had grown riotously.

It was beautiful indeed, but there were other things to catch the eye. At least a hundred hemispheres--little igloos of porcelain--were scattered about the floor of the cave. Each one was a different color. They shimmered and glittered. Scarlet, mauve, mother-of-pearl, the blue Capri, and the blue of cobalt. Pinks, yellows, oranges. Every possible shade had gone into those porcelain igloos. And the lighted walls of the cavern were covered from floor to ceiling with numberless figures, marching, fighting, working, playing. At first, Odin thought it was a vast procession of armored knights with huge chests and closed visors. But none of them stood completely erect--and each of them had two sets of arms.

Straining his eyes at the windows to look up, Odin learned that the vast ceiling was completely covered by similar figures.

In contrast to these was one huge tower of rough stone which Odin guessed to be new.

So they came to the moon, and disembarked. And at last Odin felt the lightened pull of the moon's gravity. He felt so free that he laughed and leaped into the air and turned a somersault just as he had dreamed of doing. Then one of the Brons' scientists gave him a heavy pair of shoes--as if to remind him that no man can be altogether free.

As he glumly strapped the heavy shoes to his feet, Jack thought of something his father had told him: "No man was ever really free, unless it was Robinson Crusoe. Then Friday showed up and became Crusoe's servant, and Crusoe's freedom flew away."

Forty-eight hours had pa.s.sed since they came to the cavern. Odin and Gunnar had gone with Wolden to visit the Scientist who had led the first expedition to the moon. The Scientist, whose name was Gor, was explaining: "--They were hardly out of the Iron Age. That was how we found this place.

Our instruments detected a surplus of iron in this area. They must have developed fast--for life did not last long. Insectival, beyond a doubt.

Also, they had what we call The Moon Metal. Their houses, practically everything they used, are made of that. It must have been an accident. In cooling, the moon spewed this new alloy out upon its surface. Yes, it looks like porcelain--but it is as hard as steel. It has strange vibrations.

They had musical instruments--although they may have produced tingling vibrations instead of sound. When these people saw that all was lost, they retreated here and closed the cave.

"For over a thousand years, theirs was an economy of death and rottenness.

Mushrooms and toadstools were their food. Banks of rotting mushrooms made their light. Also, it appears they had some rocks which gave out a dim glow. Even their dead went to feed the mushrooms. And so they lived. With time on their hands they covered the walls with paintings. Also, we think they must have developed their music to a high degree--though we may never know about that. Then their water and air gave out and they died."

Good heavens, Odin thought, what a cold-blooded obituary for any race!

"And so, Wolden," the Scientist continued, "it has worked out well. We were lucky to find this spot. We fashioned the two doors first, for the cave was open when we reached it--I think a meteor must have crashed here long after these people died. After that, it was easy to build the lights and to draw moisture and air from the rocks. We have struck a balance now. I said all along that it could be done, if we could escape the constant interference from those ruffians above us--uh, Odin, I beg your pardon."

Odin always resented these cracks at his people so he ignored the request by asking another question. "But how did you do all this in so short a time? Those vines look like they have been growing for years."

"Just as they do in Alaska during the growing season. We kept our suns burning all the time. Soon we may be able to afford both day and night, but not yet.

"And after that," the Scientist went on, "we were able to get back to your work on the Time-s.p.a.ce Continuum. We have made some wonderful advances. I would like to show you--but Gunnar and Odin, I am boring you."

"Wouldn't you care to look at the new lake?" Wolden urged.

"I can take a hint," Gunnar grumbled. "n.o.body wants a fighting man about until the swords are flashing--"

As Odin and Gunnar went down the front steps of the tower, they met the girl Nea. She was swinging the bowling-ball-shaped satchel at her side.

When they greeted her, Odin felt that he could hold back his curiosity no longer. "Are you a bowler, Miss Nea?" he asked.

"A bowler!" Then she laughed a silvery laugh. "Oh, no. This is an invention of mine. My father and I were working on it. He died in the tunnel when it was flooded." For a second her dark eyes appeared infinitely sad. Then she laughed again. "But it is not perfected. It may not ever be perfected now.

I thought that perhaps Wolden and Gor might help me with it."

Gunnar muttered some words that might be roughly interpreted as "Fat Chance" and he and Odin left the girl on the steps.

As they walked around the little lake which was as smooth as a mirror, Gunnar explained. "Her mother was a cousin to Maya's mother. You know how the Brons number their kin to the seventh generation. Her father was one of the Scientists. A brilliant man--but a poor provider. However, he died n.o.bly. Remember, Nors-King, Nea's branch of the family is a strange group.

They have done brilliant things, but they have thought up some hare-brained schemes, too. As I said before, she is also kin to Grim Hagen--"

Another day had pa.s.sed. The voyagers had been summoned to a council hall within the tower. A screen was set up for the convenience of those who had been left upon the Nebula.

Wolden arose to speak. "My friends, a troubled question has entered my mind. As you know, I am a man of peace. My entire life has been spent in developing theories upon what I call this subject before me. I had thought it to be something that could be developed within three generations--if we were left at peace. But we were not left at peace. And I accepted your decision that we go forth into s.p.a.ce and find Grim Hagen. But now I have learned new things. This discovery of the Moon Metal has advanced my work by fifty years. Gor here has advanced it farther. We are upon the brink of perfecting my life's work. Now, I ask that I be relieved of command. Look, you have my son Ato. A much better commander than I could ever be. Let me stay here with my work, I beg of you."

So the votes were taken, following a century-old ritual. Wolden was relieved of command and Ato was given his place.

Hours later Gunnar and Odin sat with Ato in his quarters, making some last-minute decisions.

There was a knock at the door. Wolden entered, carrying a strange-looking slug-horn that glimmered like mother-of-pearl. "I want you to take this with you," he begged his son. "It is made of the Moon-Metal. I think I know its secret now. A vibration that defies a vacuum. I hope to perfect my work, but I may not. Here," he offered the tiny horn to his son. "Blow it if you need me. It is soundless, but it defies time and s.p.a.ce just as my work does. I carry a ring to match it. I may not succeed. But blow it when you need me, son, and if I can I'll be there--"

Tears were in the eyes of both when Ato took the slug-horn from his father.

CHAPTER 8

At their request, eight couples and their children were brought from The Nebula to the cavern. For the crew of the first ship had been old men--and the cavern had never known a child's laughter.

Then Ato led his group back to the moon's surface.

As a little conveyor belt hoisted him through the tube into the central core of the ship, Jack Odin found himself worrying a bit about Nea. She had decided to go on with them. Due to her experimental interests, Jack had supposed that she would stay with Wolden. But there she was, still carrying that perplexing case of hers. Quiet and sad-eyed, a little smaller than Maya, her face a little sharper, she still looked so much like Maya that Odin couldn't get his thoughts away from her.

There was one last period of final check-outs. Then Ato gave the signal, standing lean and tall in the control room, with a tight belt about his narrow waist, and Wolden's slug-horn fastened securely to it.

The Nebula leaped toward the star-studded skies.