In short, 300 years after Leiv, a fleet arrived at the mouth of the Mediterranean. Most of the vessels were under sail although there were one or two, small, fast and inclined to blow up, that could move into the wind. The sails of the big ships bore the Great Eagle of Valhalla on a striped background alternating the colours of the sky, the snow and blood.

The Battle of Gibraltar was short. Europe had been through 200 years of stagnation.

There was no answer to cannon.

'I take the point,' said Marco. 'This Leiv is an important figure in Earth history. This is not, however, Earth.'

'It looks like Earth,' said Kin. 'An Earth that was only imagined, but Earth.'

'Are you seriously suggesting--'

'I'll tell you what I'm suggesting. I think you and Silver are right. I think humans built this place. I can't think why.'

Silver grunted. 'Surely there would be records--'

'Not if the Company suppressed them!'

It was the logical answer. The Company had built this artefact in secret. 'Jalo' had been a plant, sent to bring them here. Why would the Company build the disc? Kin thought she knew the answer, and she didn't like it. But she couldn't figure out why there had been such a performance to bring them here.

But at least it was all logical. What other answer was there? Mysterious aliens? They would have to be very mysterious. If it was the Company, Kin hated it.

'We are in danger from every quarter,' said Marco enthusiastically. 'We must wear our lift belts at all times. I suggest we move towards a centre of civilization. We might find some clues as to the disc's origins.'

'Then there's our transport,' said Kin, pointing. 'I don't know how long suit power lasts against gravity, but if there's any sea to cross I'd like to do it in a boat.'

'They may yet turn out to be hostile,' said Marco, watching the men.

'When they see you and Silver?'

In fact introducing the aliens presented a problem. Kin solved it by walking down to the encampment naked. After her earlier appearance as the goddess of mercy, she was confident that the men would sooner rape an alligator.

Leiv rushed towards her and sank to his knees. She looked down at him with an expression she hoped was benevolent.

He was smaller than most of the crew. She wondered how he exerted his authority -- until she saw the shrewd glint in his eye, even now, that said here was the master of the unsporting kick and the kidney punch. She felt glad of the stunner, now concealed in her palm.

'You're about to have an amazing opportunity to make new friends,' she said sweetly. 'This is one saga they'll never believe. OK, Silver, come on out.'

The shand appeared at the decent distance, pushing through the bushes further along the beach. As she plodded nearer several men hurried off in the other direction. When they saw her tusks several others followed them.

Grinning fit to burst, Kin walked across to the shand and put a hand in one huge, leather-palmed paw.

'Stop smiling,' she said through clenched teeth.

'I fought it would put them at eafe?'

'On you it looks hungry.'

Leiv was still standing rooted to the sand as Kin led the shand up to him. She took the man's hand in hers.

'Kneel and grovel,' she murmured.

Silver folded up obediently. Leiv looked at her and then at Kin. Finally he reached out and prodded Silver's arm.

'Good boy,' said Kin, beaming. He jumped back.

To introduce phase two Kin began to whistle the old robot-Morris tune Mrs Widgery's Lodger.

Silver danced mournfully on the sand, gazing heavenward with an expression of acute distaste. But she held the rhythm. She also moved awkwardly. Kin, who had seen her move like oiled water, admired that last touch. Anything sufficiently ungainly was funny. Funny wasn't dangerous.

The men began to trickle back. Silver danced on, kicking up little sandstorms and shuffling from one foot to the other. Kin stopped whistling.

'You've passed,' she said. 'They're practically about to feed you lumps of sugar. Have a rest. Try to avoid yawning. Marco?'

Marco hissed. He stepped out of the bushes.

In his grey ship-suit and a cloak hastily made out of a thermoblanket he looked passably human, if emaciated. His eyes were too big and his nose was too long. His face was grey as the suit.

But he had masses of flame-red hair. It wasn't really hair but it was red. Perhaps it made up for the eyes.

The men watched him warily, but no-one fled this time.

One of them stepped up to Leiv and growled something, drawing a short sword. That led to a moment of confusion that ended with Marco crouched to spring and the man lying on the sand with his sword ten feet away. Then Leiv stopped twisting his arm and took a running kick. The man screamed.

'Now we launch the boat,' said Kin firmly.

Silver padded towards the beached vessel and braced herself with a shoulder against the prow. Nothing happened for a moment, and then the boat slid down the beach, only stopping when the stern was moving urgently in the current.

Kin took Leiv's arm and led him firmly towards it. He was quick on the uptake. Within five minutes the men were on board, the dumbwaiter was humming to itself by the mast, and all eyes were on Silver, hovering out to sea on the end of the cable.

There was an area of dead water where the sea parted round the island before dropping into nothingness. By the time the current tugged feebly at it the boat was flying over the waves.

Two incidents enlivened the journey. Marco was handed a horn of some sweet substance by a nervous Leiv.

He sniffed it suspiciously and poured some into the 'waiter. 'It appears to be some kind of glucose drink,' he said. 'What do you think, Kin?'

'Did you try it on the 'waiter?'

'It gave a green light. Could it be some form of strengthening potion?'

He drank half the horn, and smacked what passed for lips. Then he laughed vaguely and drank the other half.

Later he programmed the dumbwaiter to duplicate it, and when the men had got over their amazement at the disposable plastic cups they were passed back as fast as they could be filled. Spasmodic singing broke out, and there was an occasional clattering of oars as rowers missed their stroke. Finally Kin, after Leiv's unspoken plea, switched off the machine.

Later Silver tried her hand at rowing. Sitting amidships and grasping two oars, she followed the stroke easily. One by one the rowers stopped to watch her. The boat didn't slow until her oars snapped.

Marco found Kin sitting in the skin shelter behind the mast, drinking martinis and thinking.

'I wish a private word,' he said.

'Fine,' said Kin, patting the rug beside her. 'How is the head now?'

'Better. That drink obviously contains dangerous impurities. I don't think I will try any more for an hour or so.' He fished in his belt pouch and pulled out a roll of plastic. It opened out into an aerial photograph of the disc.

'I got the computer to prepare it before we left the ship,' he said.

'Why didn't you show it to me before?'

'I did not wish to encourage any foolhardy explorations. However, now that we are penetrating the disc... Look at the photo. What is missing?'

Kin took the sheet. 'A lot,' she said. 'You know that. No Valhalla. That's why Leiv found the waterfall. No Brasil. The Peaceful Ocean is tiny, look, round here on the back of Asia--'

'Any additions?'

Kin peered at the map. 'I don't know,' she said. Marco used a double-jointed thumb to point to the centre of the disc.

'The cloud cover makes it a bit indistinct, but that shouldn't be there. That island in the Arabian Sea. You notice it's perfectly circular? It is the geographical hub of the disc.'

'What about it?'

'Don't you see? It is an anomaly. We'll find the disc civilization there if anywhere. These people are barbarians. Intelligent, yes -- but space-going?'