'Only predict.' Charles Sub-Lunar, from The Lights In The Sky Are Photofloods

In the false dawn a warm wind blew out of the east, shaking the dry reed cases.

The marsh mist broke into ribbons and curled away. Small night creatures burrowed hastily into the slime. In the distance, hidden by the baroque mist curls, a night bird screeched in the floating reed beds.

In one of the big lakes near the open sea three delicate white windshells hoisted their papery sails and tacked slowly towards the incoming surf.

Dom waited just beyond the breakers, two metres below the dancing surface, a thin stream of bubbles rising from his gill pack. He heard the shells long before he saw them. They sounded like skates on distant ice.

He grinned to himself. There would only be one chance. Some of those pretty trailing tendrils were lethal. There might never be another chance, ever. He tensed.

And knifed upwards.

The shell bucked violently as he grabbed the blunt prow, and he swung his legs hard over to avoid hitting the dangling green fronds. The world dissolved into a salt-tasting, cold white bubble of foam. Small silver fish slipped desperately past him, and then he was lying across the upper hull.

The shell had gone berserk, flailing with the bony mast in great slow sweeps. Dom watched it, getting his breath back, and then half-leapt, half-scrambled to the big white bulge near the base of the mast.

A shadow passed over him, and he rolled to one side as the mast nicked a furrow in the hull. As it passed he followed it, grabbed at the nerve knot, and pulled himself forward.

His fingers sought for the right spot. He found it.

The shell stopped its frenzied rush through the wavetops, hitting the water again with a slap that jarred Dom's teeth. The sail wavered uncertainly.

Dom continued stroking until the creature was soothed and then stood up.

It didn't count unless you stood up. The best dagon fishers could ride a shell with their toes. How he had envied them - and how carefully he had watched from the family barge on feast days, when the fishermen came in two or three hundred abreast on their half-tame shells with See-Why setting, a bright purple star, into the sea. Some of the younger men danced on their shells, spinning and leaping and juggling torches and all the time keeping the shell under perfect control.

Kneeling in front of the nerve knot he guided the big semi-vegetable back through the twisting waterways of the marsh, through acres of sea lilies and past floating reed islands. On several of them blue flamingoes hissed at him and stalked imperiously away.

Occasionally he glanced up and northwards, searching for tell-tale specks in the air. Korodore would find him eventually, but Dom was pretty certain that he wouldn't pick him up straight away. He'd probably keep him under benevolent observation for a few hours because, after all, Korodore had been young once. Even Korodore. Whereas Grandmother gave the impression that she had been born aged eighty.

Besides, Korodore would bear in mind that tomorrow Dom would be Chairman and legally his boss. Dom doubted if that would influence him one jot. Old Korodore relished duty if it came sternly...

He smiled proudly as the shell cut smoothly through the quiet water. At least the fishermen would not be able to call him a blackhand, even if he wasn't quite a fully-fledged greenhand. That last initiation of the dagon fishermen could only be got out in the deeps, on a moonlit night, when the dagons rose out of the deep with their razor-sharp shells agape.

The shell bumped against the reed bed and Dom leapt lightly ashore, leaving it drifting in the little lagoon.

Joker's Tower, which had been dominating the western sky, loomed up before him. He hurried forward.

See-Why had risen and bathed the slim pyramid in pink light. The mist had left the reed beds round the base but the apex, five miles above the sea, was lost in perpetual cloud. Dom pushed his way through the dry reeds until he was within half a metre of the smooth, milk-white wall.

He reached out gingerly.

Hrsh-Hgn had once, realizing vaguely that interminable lectures on planetary economics might not be palatable fare for a boy, smiled and switched off the faxboard. He had fetched his copy of Sub-Lunar's Galactic Chronicles and told Dom about the Jokers.

'Name the races classed as Human under the Humanity Act,' he began.

'Phnobes, men, drosks and the First Sirian Bank,' Dom rattled off. 'Also Class Five robots by Sub-Clause One may apply for Human Status.'

'Yess. And the other racess?'

Dom ticked them off on his fingers. 'Creapii are Super-Human. Class Four robots are sub-human, sundogs are unclassified.'

'Yess?'

'The other races I'm not sure about,' admitted Dom. 'The Jovians and the rest. You never taught me anything about them.'

'It iss not necessary. They are so alien, you undersstand. We share no common ground. Things humanity considers universal among self-aware races - a sense of identity, for example - are merely products of a temperate bipedal evolution. But all the fifty-two races so far discovered arose in the last five million standard years.'

'You told me about that yesterday,' said Dom, 'Sub-Lunar's Theory of Galactic Sapience.'

Then the phnobe had told him about the jokers. The creapii had found the first joker tower and, all else having failed to open it, had dropped a live nigrocavernal matrix on it. The tower was later found to be intact. Three neighbouring stellar systems had been wrecked, however.

The phnobes never discovered a joker tower: they had always known of one. The tower of Phnobis, rising from the sea into the perpetual cloud cover, was the cause and basis of the planet-wide Frss-Gnhs religion - literally, Pillar of the Universe.

Earth-human colonists had found seven, one of them floating in the asteroid belt of the Old Sol system. That was when the Joker Institute was set up.

The young races of men, creapii, phnobe and drosk found themselves watching one another in awe across a galaxy littered with the memories of a race that had died before human time began. And out of that awe arose the legends of Jokers' World, the glittering goal that was to taunt adventurers and fools and treasure hunters across the light years...

Dom touched the tower. There was the faintest tingle, a sudden stab of pain. He leapt back, frantically rubbing life back into his frozen fingers. The coldness of the towers was always greatest at noon, when they drank in heat, yet grew icy.

Dom set off round the tower, feeling the cold reaching out towards him. Looking up he thought he saw the air within a foot of the smooth walls darken, as if light was just a gas and was being sucked in by the spire. It wasn't logical, but the idea had a certain artistic appeal.

Towards noon a security flyer glittered briefly on the western horizon, heading south. Dom stepped sideways into a clump of reeds... And wondered what he was doing in the marsh. Freedom, that was it. The last day of real freedom. His last chance to see Widdershins without a security guard standing on either side of him and a score of more subtle protections all round. He had planned it, down to squashing Korodore's ubiquitous robot insects that spied on him - always for his own protection - in his bedroom.

And now he'd have to go home and face Grandmother. He was beginning to feel just a little foolish. He wondered what he had expected from the tower: some feeling of cosmic awe, probably, a sense of the deeps of Time. Certainly not this sinister, insidious sensation of being watched. It was just like being at home.