Behind him Mith was silent for a long time. Then he said, "What can we do?"

"Beats me," said Hollerbach, a little harshly. "You're the Captain."

Mith got out of his chair and lumbered up to Hollerbach; his breath was hot on the old Scientist's neck, and Hollerbach could feel the pull of the Captain's weighty gut. "d.a.m.n it, stop patronizing me. What am I supposed to tell the crew?"

Abruptly Hollerbach felt very tired. He reached with one hand for the door frame and wished his chair weren't so far away. "Tell them not to give up hope," he said quietly. "Tell them we're doing all we know how to do. Or tell them nothing. As you see fit."

Mith thought it over. "Of course, not all your results are in." There was a trace of hope in his voice. "And you haven't completed that machine overhaul, have you?"

Hollerbach shook his head, eyes closed. "No, we haven't finished the overhaul."

"So maybe there's something wrong with the machines after all." Mith clapped his shoulder with a plate-sized hand. "All right, Hollerbach. Thanks. Look, keep me informed."

Hollerbach stiffened. "Of course."

Hollerbach watched Mith stride away across the deck, his belly oscillating. Mith wasn't too bright - but he was a good man. Not as good as his father, maybe, but a lot better than some of those who were now calling for his replacement.

Maybe a cheerful buffoon was right for the Raft in its present straits. Someone to keep their spirits up as the air turned to poisonHe laughed at himself. Come on, Hollerbach; you really are turning into an old fart.

He became aware of a p.r.i.c.kling over his bald pate; he glared up at the sky. That star overhead was a searing pinpoint, its complex orbit bringing it ever closer to the path of the Raft. Close enough to burn the skin, eh? He couldn't remember a star being allowed to fall so threateningly close before; the Raft should have been shifted long since. He'd have to get on to Navigator Cipse and his boys. He couldn't think what they were playing at.

Now a shadow swept across him, and he made out the silhouette of a tree rotating grandly far above the Raft. That would be Pallis, returning from the Belt. Another good man, Pallis... one of the few left.

He dropped his p.r.i.c.kling eyes and studied the deck plates beneath his feet. He thought of the human lives that had been expended on keeping this little metal island afloat in the air for so long.

And was it only to come to this, a final few generations of sour sullenness, falling at last to the poisoned air?

Maybe it would be better not to move the Raft out from under that star. Let it all go up in one last blaze of human glory"Sir?" Grye, one of his a.s.sistants, stood before him; the little round man nervously held out a battered sheaf of paper. "We've finished another test run."

So there was still work to do. "Well, don't stand about like that, man; if you're no use you're certainly no ornament. Bring that in and tell me what it says."

And he turned and led the way into his office.

The Raft had grown in the sky until it blocked out half the Nebula. A star was poised some tens of miles above the Raft, a turbulent ball of yellow fire a mile wide, and the Raft cast a broadening shadow down through miles of dusty air.

Under Pallis's direction Rees and Gover stoked the fire bowls and worked their way across the surface of the tree, waving large, light blankets over the billowing smoke. Pallis studied the canopy of smoke with a critical eye; never satisfied, he snapped and growled at the boys. But, steadily and surely, the tree's rise through the Nebula was moulded into a slow curve towards the Rim of the Raft.

As he worked Rees chanced the wrath of Pallis by drinking in the emergent details of the Raft. From below it showed as a ragged disc a half-mile wide; metal plates scattered highlights from the stars and light leaked through dozens of apertures in the deck. As the tree sailed up to the Rim the Raft foreshortened into a patchwork ellipse; Rees could see the sooty scars of welding around the edges of the nearer plates, and as his eye tracked across the ceiling-like surface the plates crowded into a blur, with the far side of the disc a level horizon.

At last, with a rush of air, the tree rose above the Rim and the upper surface of the Raft began to open out before Rees. Against his will he found himself drawn to the edge of the tree; he buried his hands in the foliage and stared, open-mouthed, as a torrent of color, noise and movement broke over him.

The Raft was an enormous dish that brimmed with life. Points of light were sprinkled over its surface like sugar-sim over a confectionery. The deck was studded with buildings of all shapes and sizes, constructed of wood panels or corrugated metal and jumbled together like toys. All around the Rim machines as tall as two men hulked like silent guardians; and at the heart of the Raft lay a huge silver cylinder, stranded like a trapped whale among the box-like constructions.

A confusion of smells a.s.saulted Rees's senses - sharp ozone from the Rim machines and other workshops and factories, woodsmoke from a thousand chimneys, the hint of exotic cooking scents from the cabins.

And people - more than Rees could count, so many that the Belt population would be easily lost among them - people walked about the Raft in great streams; and knots of running children exploded here and there into bursts of laughter.

He made out st.u.r.dy pyramids fixed to the deck, no more than waist high. Rees squinted, scanning the deck; the pyramids stood everywhere. He saw a couple lingering beside one, talking quietly, the man scuffing the metal cone with one foot; and there a group of children chased through a series of the pyramids in a complicated game of catch.

And out of each pyramid a cable soared straight upwards; Rees tilted his face back, following the line of the cables, and he gasped.

To each cable was tethered the trunk of a tree.

To Rees one flying tree had been wonder enough. Now, over the Raft, he was faced with a mighty forest. Every tethering cable was vertical and quite taut, and Rees could almost feel the exertion of the harnessed trees as they strained against the pull of the Core. The light of the Nebula was filtered by its pa.s.sage through the rotating ranks of trees, so that the deck of the Raft was immersed in a soothing gloom; around the forest dancing skitters softened the light to pastel pink.

Rees's tree rose until it pa.s.sed the highest layer of the forest. The Raft turned from a landscape back into an island in the air, crowned by a ma.s.s of shifting foliage. The sky above Rees seemed darker than usual, so that he felt he was suspended at the very edge of the Nebula, looking down over the mists surrounding the Core; and in all that universe of air the only sign of humanity was the Raft, a sc.r.a.p of metal suspended in miles of air.

There was a heavy hand on his shoulder. Rees started. Pallis stood over him, the canopy of smoke a backdrop to his stern face. "What's the matter?" he growled. "Never seen a few thousand trees before?"

Rees felt himself flush. "I..."

But Pallis was grinning through his scars. "Listen, I understand. Most people take it all for granted. But every time I see it from outside - it gives me a kind of tingle." A hundred questions tumbled through Rees's mind. What would it be like to walk on that surface? What must it have been like to build the Raft, hanging in the void above the Core?

But now wasn't the time; there was work to do. He got to his feet, wrapping his toes in the foliage like a regular woodsman.

"Now, then, miner," Pallis said, "we've got a tree to fly. We have to drop back into that forest. Let's get the bowls br.i.m.m.i.n.g; I want a canopy up there so thick I could walk about on it. All right?"

At last Pallis seemed satisfied with the tree's position over the Raft. "All right, lads. Now!"

Gover and Rees ran among the fire bowls, shoving handfuls of damp wood into the flames. Smoke rolled up to the canopy above them. Gover coughed as he worked, swearing; Rees found his eyes streaming, the sooty smoke scouring his throat.

The tree lurched beneath them, almost throwing Rees into the foliage, and began to fall clear of its canopy of smoke. Rees scanned the sky: the falling stars wheeled by noticeably slower than before; he guessed that the tree had lost a good third of its rotation in its attempt to escape smoke's darkness.

Pallis ran to the trunk and uncoiled a length of cable. He thrust his neck and shoulders down through the foliage and began to pay out the cable; Rees could see how he worked the cable to avoid snagging it on other trees.

At last the tree was sliding through the outer layers of the forest. Rees peered across at the trees they pa.s.sed, each slowly turning and straining with dignity against its tether. Here and there he made out men and women crawling through the foliage; they waved to Pallis and called in distant voices.

As it entered the gloom of the forest Rees sensed the tree's uncertainty. Its leaves turned this way and that as it tried to a.s.sess the irregular patterns of light playing over it. At last it came to a slow, grand decision, and its turning accelerated; with a smooth surge it rose by a few yards-and came to an abrupt halt. The cable attached to its trunk was taut now; it quivered and bowed through the air as it hauled at the tree. Rees followed the line of the cable; as he had expected its far end had reached the deck of the Raft, and two men were fixing it firmly to one of the waist-high pyramids.

He got to his knees and touched the familiar wood. Sap rushed through the shaped branch, making its surface vibrate like skin; Rees could sense the tree's agitation as it strove to escape this trap, and he felt an odd sympathy pull at his stomach.

Pallis made some final tests of the cable and then walked briskly around the wooden platform, checking that all the glowing bowls had been doused. At last he returned to the trunk and pulled a bundle of paperwork from a cavity in the wood. He crouched down and slipped through the foliage with a quiet rustle - and then popped his head back through. He peered around until he spotted Rees. "Aren't you coming, lad? Not much point staying here, you know. This old girl won't be going anywhere for a good few shifts. Well, come on; don't keep Gover from his food."

Hesitantly Rees made his way to the trunk. Pallis dropped through first. When he'd gone Gover hissed: "You're a long way from home, mine rat. Just remember - nothing here is yours. Nothing." And the apprentice slipped into the screen of leaves.

Heart thumping, Rees followed.

Like three water drops they slid down their cable through the scented gloom of the forest.

Rees worked his way hand over hand down the thin cable. At first the going was easy, but gradually a diffuse gravity field began to tug at his feet. Pallis and Gover waited at the base of the cable, peering up at him; he swung through the last few feet, avoiding the sloping sides of the anchor cone, and landed lightly on the deck.

A man walked up bearing a battered clip pad. The man was huge, his black hair and beard barely concealing a mask of scars more livid than Pallis's. A fine black braid was attached to the shoulder of his coverall. He scowled at Rees; the boy flinched at the power of the man's gaze. "You're welcome back, Pallis," the man said, his voice grim. "Although I can see from here you've brought back half your stock."

"Not quite, Decker," said Pallis coolly, handing over his paperwork. The two men moved into a huddle and went through Pallis's lists. Gover scuffed impatiently at the deck, wiping his nose against the back of his hand.

And Rees, wide-eyed, stared.

The deck beneath his feet swept through a network of cables away into a distance he could barely comprehend. He could see buildings and people set out in great swathes of life and activity; his head seemed to spin with the scale of it all, and he almost wished he were back in the comforting confines of the Belt.

He shook his head, trying to dispel his dizziness. He concentrated on immediate things: the easy pull of gravity, the gleaming surface beneath his feet. He tapped experimentally at the deck. It made a small ringing noise.

"Take it easy," Pallis growled. The big tree-pilot had finished his business and was standing before him. "The plate's only a millimeter thick, on average. Although it's b.u.t.tressed for strength."

Rees flexed his feet and jumped a few inches into the air, feeling the pull as he settled gently back. "That feels like half a gee."

Pallis nodded. "Closer to forty per cent. We're in the gravity well of the Raft itself. Obviously the Nebula Core is also pulling at us - but that's tiny; and in any event we couldn't feel it because the Raft is in orbit around the Core." He tilted his face up at the flying forest. "Most people think the trees are there to keep the Raft from falling into the Core, you know. But their function is to stabilize the Raft - to keep it from tipping over - and to counteract the effects of winds, and to let us move the Raft when we have to..." Pallis bent and peered into Rees's face, his scars a crimson net. "Are you OK? You look a little dizzy."

Rees tried to smile. "I'm fine. I suppose I'm just disconcerted at not being in a five-minute orbit."

Pallis laughed. "Well, you'll get used to it." He straightened. "Now then, young man, I have to decide what's to be done with you."

Rees felt a coldness p.r.i.c.kle over his scalp as he began to think ahead to the moment when he would be abandoned by the tree-pilot, and scorn for himself ran through his thoughts. Had he boldly left his home only to become dependent on the kindness of a stranger? Where was his courage?

He straightened his back and concentrated on what Pallis was saying.

"...I'll have to find an Officer," the pilot mused, scratching a stubbly chin. "Log you as a stowaway. Get you a temporary Cla.s.s a.s.signment until the next tree goes out. All that paperwork, d.a.m.n it...

"By the Bones, I'm too tired. And hungry, and dirty. Let's leave it until next shift. Rees, you can stop over at my cabin until it's sorted. You too, Gover, though the prospect is hardly enticing."

The apprentice stared into the distance; he didn't look around at the pilot's words.

"But I don't have supplies for three growing lads like us. Or even one, come to think of it. Gover, get out to the Rim and get a couple of shifts' worth on my number, will you? You too, Rees; why not? You'll enjoy the sightseeing. I'll go sc.r.a.pe a few layers of dust off my cabin."

And so Rees found himself trailing the apprentice through the swarm of cables. Gover stalked ahead, not deigning to wait; in all this murky, tree-shadowed world the apprentice was Rees's only fixed point, and so the miner made sure he didn't lose sight of Gover's unprepossessing back.

They came to a thoroughfare cut through the tangle of cables. It was crowded with people. Gover paused at the edge of the thoroughfare and stood in sullen silence, evidently waiting for something. Rees stood beside him and looked around. The clear, straight path was about ten yards wide: it was like looking along a tree-roofed tunnel. The path was lined with light; Rees made out globes fixed to the cables just like the globes in the depths of the star mine.

There were people everywhere, an even stream that flowed briskly in both directions along the path. Some of them stared at Rees's dishevelled appearance, but most politely looked away. They were all clean and well-groomed - although there were hollow eyes and pale cheeks, as if some sickness were haunting the Raft. Men and women alike wore a kind of coverall of some fine, gray material; some wore gold braid on their shoulders or cuffs, often woven in elaborate designs. Rees glanced down at his own battered tunic - and with a jolt recognized it as an aged descendant of the garments of the Raft population. So miners wore Raft cast-offs?

He wondered what Sheen would say about that...

Two small boys were standing before him, gazing with round eyes at his dingy tunic. Rees, horribly embarra.s.sed, hissed to Gover: "What are we waiting for? Can't we move on?"

Gover swivelled his head and fixed Rees with a look of dull contempt.

Rees tried to smile at the boys. They just stared.

Now there was a soft, rushing sound from the center of the Raft. Rees, with some relief, stepped out into the thoroughfare, and he made out the bizarre sight of a row of faces sliding towards him above the crowd. Gover stepped forward and held up a hand. Rees watched him curiously-and the rushing grew to a roar. Rees turned to see the blunt prow of a Mole bearing down on him. He stumbled back; the speeding cylinder narrowly missed his chest. The Mole rolled to a halt a few yards from Gover and Rees. A row of simple seats had been fixed to the upper surface of the Mole; people rode in them, watching him incuriously.

Rees found his mouth opening and closing. He had expected some wonderful sights on the Raft, but - this? The little boys' mouths were round with astonishment at his antics. Gover was grinning. "What's the matter, mine rat? Never seen a bus before?" The apprentice walked up to the Mole and, with a practiced swing, stepped up into a vacant seat.

Rees shook his head and hurried after the apprentice. There was a low shelf around the base of the Mole; Rees stepped onto it and turned cautiously, lowering himself into the seat next to Gover's - and the Mole jolted into motion. Rees tumbled sideways, clinging to chair arms; he had to wriggle around until he was facing outwards, and at last found himself gliding smoothly above the heads of the throng.

The boys ran after the Mole, shouting and waving; Rees did his best to ignore them, and after a few yards they tired and gave up.

Rees stared frankly at the man next to him, a thin, middle-aged individual with a sheaf of gold braid at his cuff. The man studied him with an expression of disdain, then moved almost imperceptibly to the far side of his seat.

He turned to Gover. "You call me a 'mine rat.' What exactly is a 'rat'?"

Gover sneered. "A creature of old Earth. A vermin, the lowest of the low. Have you heard of Earth? It's the place we-" he emphasized the word "-came from."

Rees thought that over; then he studied the machine he was riding. "What did you call this thing?"

Gover looked at him with mock pity. "This is a bus, mine rat. Just a little something we have here in the civilized world."

Rees studied the lines of the cylinder under its burden of furniture and pa.s.sengers. It was a Mole all right; there were the scorch marks showing where - something - had been cut away. On an impulse he leaned over and thumped the surface of the "bus" with his fist. "Status!"

Gover studiously ignored him. Rees was aware of his thin neighbor regarding him with curious disgust-and then the bus reported loudly, "Ma.s.sive sensor dysfunction."

The voice had sounded from somewhere under the thin man; he jumped and stared open-mouthed at the seat beneath him.

Gover looked at Rees with a grudging interest. "How did you do that?"

Rees smiled, relishing the moment. "Oh, it was nothing. You see, we have - ah - buses where I come from too. I'll tell you about it some time."

And with a delicious coolness he settled back to enjoy the ride.

The journey lasted only a few minutes. The bus paused frequently, pa.s.sengers alighting and climbing aboard at each stop.

They pa.s.sed abruptly out of the ma.s.s of cables and slid over a clear expanse of deck. Unimpeded Nebula light dazzled Rees. When he looked back the cables were like a wall of textured metal hundreds of feet tall, topped by discs of foliage.

The nose of the bus began to rise.

At first Rees thought it was his imagination. Then he noticed the pa.s.sengers shifting in their seats; and still the tilt increased, until it seemed to Rees that he was about to slide back down a metal slope to the cables.

He shook his head tiredly. He had had enough wonders for one shift. If only Gover would give him a few hints about what was going onHe closed his eyes. Come on, think it through, he told himself. He thought of the Raft as he had seen it from above. Had it looked bowl-shaped? No, it had been flat all the way to the Rim; he was sure of that. Then what?

Fear shot through him. Suppose the Raft was falling! Perhaps the cables on a thousand trees had snapped; perhaps the Raft was tipping over, spilling its human cargo into the pit of airHe snorted as with a little more thought he saw it. The bus was climbing out of the Raft's gravity well, which was deepest at the structure's center. If the bus's brakes failed now it would roll back along the plane in from the Rim towards the Raft's heart... just as if it were rolling downhill. In reality the Raft was, of course, a flat plate, fixed in s.p.a.ce; but its central gravity field made it seem to tilt to anyone standing close to the Rim.

When the slope had risen to one in one the bus shuddered to a halt. A set of steps had been fixed to the deck alongside the bus's path; they led to the very Rim. The pa.s.sengers jumped down. "You stay there," Gover told Rees; and he set off after the others up the shallow stairs.

Fixed almost at the Rim was the huge, silhouetted form of what must be a supply machine. The pa.s.sengers formed a small queue before it.

Rees obediently remained in his seat. He longed to examine the device at the Rim. But there would be another shift, time and fresh energy to pursue that.

It would be nice, though, to walk to the edge and peer into the depths of the Nebula... Perhaps he might even glimpse the Belt.

One by one the pa.s.sengers returned to the bus bearing supply packets, like those which Pallis had brought to the Belt. The last pa.s.senger thumped the nose of the bus; the battered old machine lurched into motion and set off down the imaginary slope.

Pallis's cabin was a simple cube part.i.tioned into three rooms: there was an eating area, a living room with seats and hammocks, and a cleaning area with a sink, toilet and shower head.

Pallis had changed into a long, heavy robe. The garment's breast bore a stylized representation of a tree in the green braid which Rees had come to recognize as the badge of Pallis's woodsman Cla.s.s. He told Rees and Gover to clean themselves up. When it was Rees's turn he approached the gleaming spigots with some awe; he barely recognized the clean, sparkling stuff that emerged as water.

Pallis prepared a meal, a rich meat-sim broth. Rees sat cross-legged on the cabin floor and ate eagerly. Gover sat in a chair wrapped in his customary silence.

Pallis's home was free of decoration save for two items in the living area. One was a cage constructed of woven slats of wood, suspended from the ceiling; within it five or six young trees hovered and fizzed, immature branches whirling. They filled the room with motion and the scent of wood. Rees saw how the skitters, one or two adorned with bright flowers, fizzed towards the cabin lights, b.u.mping in soft frustration against the walls of their cage. "I let them out when they're too big," Pallis told Rees. "They're just - company, I suppose. You know, there are some who bind up these babies with wire to stunt their growth, distort their shapes. I can't envisage doing that. No matter how attractive the result."

The other item of decoration was a photograph, a portrait of a woman. Such things weren't unknown in the Belt - the ancient, fading images were handed down through families like shabby heirlooms - but this portrait was fresh and vivid. With Pallis's permission Rees picked it up-and with a jolt he recognized the smiling face.