The sand?' said Shadwell. 'You think that was the sand?'

The boy shook his head.

'Of course not,' said Shadwell. That's the voice of the one we've come to meet.'

Jabir threw a handful of bone-white sticks onto the fire. It devoured them immediately.

'Do you understand?' Shadwell asked.

Ibn Talaq looked up from his work, and stared at Shadwell.

They understand,' said Hobart.

'I thought maybe they'd lose their nerve.'

Ibn Talaq seemed to sense the implication of this remark.

'Rub al Khali,' he said, 'we know. All of it. We know.'

Shadwell grasped the point. They were Murra. Their tribe laid claim to this territory as its own. To retreat before the mysteries of the Empty Quarter would be tantamount to disinheritance.

'How close are we?' said Hobart.

'I don't know,' Shadwell replied. 'You heard it the same as me. Perhaps very near.'

'Do you think it knows we're here?' said Hobart.

'Perhaps,' said Shadwell. 'Does it matter?'

'I suppose not.'

'If it doesn't know tonight, it will by tomorrow.'

2.

They set out at dawn the next day, to cover as much distance as they could before the sun mounted too high, following the same bearing as they'd followed on the previous four days.

For the first time in their journey the landscape they were crossing showed some subtle change, as the rhythmical rise and fall of the dunes gave way to much larger, irregular rises.

The sand of these hills was soft, and collapsed in sibilant avalanches beneath the feet of animal and human alike. Nobody could ride. The travellers coaxed the animals, still jittery after the night before, up the ever steeper slopes with curses and kindness in equal measure, only to reach the top and find a yet larger dune ahead of them.

Without any words being exchanged, Ibn Talaq had relinquished his position at the head of the quartet, and it was Shadwell who now set the pace, leading the party up the faces of the dunes and down into the troughs between. There, the subtlest of winds blew, more distressing in its ingratiating way than any storm, for it seemed to whisper as it ran over the sand, its message just beyond the reach of comprehension.

Shadwell knew what words it carried, however: Climb, it said, climb if you dare. One more hill, and you'll find all you ever wanted waiting - and with its coaxing he'd lead the way up the next slope, out of the cool shadow and into the blinding sunlight.

They were close, Shadwell knew; very close. Though, in the early afternoon, Jabir began to complain, demanding that they rest the animals, Shadwell would have none of it. He forced the pace, his mind divided from his body's discomfort; almost floating. Sweat was nothing; pain was nothing. All of it could be endured.

And then, at the top of a dune it had taken the better part of an hour to climb, the murmurs in the wind were confirmed.

They had left the dunes behind them. Ahead the terrain was absolutely flat as far as the eye could see, though that wasn't many miles, for the wind carried a cargo of sand that veiled the horizon like smoke. Even in the Rub al Khali this wasteland was a new refinement of desolation: a connoisseur's nowhere.

'God Almighty,' said Hobart, as he climbed to where Shadwell stood.

The Salesman took hold of Hobart's arm. His breath was rapid and rasping; his sun-skinned face dripped sweat.

'Don't let me fall,' he murmured. 'We're close now.'

'Why don't we wait awhile before going any farther?' said Hobart. 'Maybe rest, until tomorrow?'

'Don't you want to meet your Dragon?' Shadwell asked.

Hobart said nothing to this.

Then I'll go alone,' was Shadwell's response. He dropped the camel's reins and began to stagger down the slope to meet the plain.

Hobart scanned the sterility before him. What Shadwell said was true: they were close, he felt it. And that thought, which days ago had excited him, now put a terror into him. He'd seen enough of the Quarter to know that the Dragon that occupied it was not the glittering monster of his dreams. It defied his imagination to conjure the terror that nested in such a place.

But one thing he knew: it would care not at all for the Law, or its keepers.

He might turn from it still, he thought, if he were resolute. Persuade the guides that Shadwell was leading them to extinction, and that they'd all be wiser leaving the Salesman to his insanity. Already Shadwell was at the bottom of the slope, and marching away from the dune, not even bothering to glance behind him to see that the rest were following. Let him go, a part of Hobart said: let him have his Scourge if that's what he wants; and death too.

But fearful as he was he couldn't quite bring himself to turn his back on the wasteland. His mind, which was narrowed now to a tunnel, showed him again his hands alive with an unconsuming flame. In that rare moment of vision he'd tasted power he'd never quite been able to put words to, and nothing his subsequent experience had brought - the defeats and humiliations - could extinguish the memory.

Somewhere, far from here, those who'd defeated him -who'd perverted the Laws of the real and the righteous still lived. To go back amongst them with fire at his fingertips and lay their wretched heads low - that was an ambition worth enduring the wasteland for.

Dreaming of flame, he took up the reins of Shadwell's camel, and followed in the Salesman's footsteps down onto the mirror-bright sand.

III.

THE WALL.

Distance was impossible to judge on the plain they now crossed. The dunes at their backs were soon obscured by the sand-thickened air, and ahead, the same veil shut the vista from sight. Though the wind was insistent, it did nothing to alleviate the assault of the sun: it merely added misery to misery, dragging at the legs until every step was a torment. But nothing slowed Shadwell. He marched like a man possessed until - after an hour of this inferno - he stopped dead, and pointed through the blur of heat and wind. There,' he said.

Hobart, who'd come abreast of him, narrowed his dazzled eyes and followed the direction of Shadwell's finger. But the sand clouds defied his scrutiny. 'Nothing,' he said. Shadwell seized hold of his arm. 'Damn you, look.'

And this time Hobart realized Shadwell was not deceived. Some distance from where they stood the ground seemed to rise up again.

'What is it?' Hobart shouted against the wind. 'A wall,' Shadwell said.

It looked more like a range of hills than a wall, Hobart thought, for it ran along the entire visible horizon. Yet, though there were breaks in its length here and there, its regularity suggested Shadwell's judgement was correct. It was indeed a wall.

Without further exchange, they began the march towards it.

There was no sign of any structure rising on the far side, but its builders must have valued whatever it had been made to enclose and protect, for with every yard they drew closer, its sheer scale became awesomely apparent. It rose fifty feet or more above the desert floor; yet such was the skill of the masons there was no visible sign of how it had been constructed.

Twenty yards from the wall the party halted, leaving Shadwell to approach it unaccompanied. He stretched his hand out to touch the stone, which was hot beneath his finger-tips, its surface so smooth it was almost silken. It was as if the wall had been raised out of molten rock, shaped by intelligences that could mould lava like cold clay. Clearly there was no practical way of scaling a surface so innocent of niche or scar, even if any of them had possessed the energy to do so.

There must be a gate,' said Shadwell. 'We'll walk 'til we find it.'

The sun was well past its peak now, the day beginning to cool. But the wind was not about to give the travellers a moment's respite. It seemed to be keeping guard along the wall, lashing at their legs as though eager to throw them to the ground. But having got so far without being slaughtered, the party's fears had been replaced by curiosity as to what lay on the other side. The Arabs had found their voices again, and kept up a constant dialogue, doubtless planning how they'd boast of their find once home.