I thought in wonder of the sea-shells to be picked up from the desert a thousand miles from the sea but had no foreshadowing that I would be picking them myself. The night was calm and still. I suddenly became aware of the startling incongruity of Max Stafford, hot-shot businessman from the City of London, lying in a place improbably called Atakor beneath the Finger of God which was not far from the End of the World.

Suddenly London ceased to matter. Lord Brinton and Andrew McGovern ceased to matter; Charlie Malleson and Jack Ellis ceased to matter; Gloria and Alix Aarvik ceased to matter. All the pettifogging business of our so-called civilization seemed to slough away like an outworn skin and I felt incredibly happy. I slept.

I woke in the thin light of dawn conscious of movement and sound. When I lifted my head I saw Byrne filling the petrol tank from a jerrican – it was that metallic noise that had roused me. I leaned up on one elbow and saw Mokhtar in the desert mosque; he was making obeisances to the east in the dawn ritual of Islam. I waited until he had finished because I did not want to disturb his devotions, then I arose.

Thirty minutes later after a breakfast of cold roast venison, bread and hot mint tea we were on our way again, a long plume of dust stretching away behind us. Slowly the majestic peak of Ilamen receded and new vistas of tortured rock came into view. According to Byrne, we were on a well-travelled road but to a man more accustomed to city streets and motorway driving that seemed improbable. The so-called road was vestigial, distinguishable only by boulders a shade smaller than those elsewhere, and the truck was taking a beating. As for it being well-travelled I did not see a single person moving on it all the time I was in Atakor.

Nearly three hours later Byrne pointed ahead. 'Assekrem!'

There was a large hill or a small mountain, depending on how you looked at it, on the top of which appeared to be a building. 'Is that a house?' I asked, wondering who would build on a mountain top in the middle of a wilderness.

'It's the Hermitage. Tell you about it later.'

We drove on and, at last, Byrne stopped at the foot of the mountain. There seemed to be traces of long-gone cultivation about; the outlines of fields and now dry irrigation ditches. Byrne said, 'Now we climb to the top.'

'For God's sake, why?'

'To see what's on the other side,' he said sardonically. 'Come on.'

And so we climbed Assekrem. It was by no means a mountaineering feat; a track zig-zagged up the mountain, steep but not unbearably so, and yet I felt out of breath and panted for air. Half-way up Byrne obligingly stopped for a breather, although he did not seem in discomfort.

I leaned against the rock wall. 'I thought I was fitter than this.'

'Altitude. When you get to the top you'll be nine thousand feet high.'

I looked down to the plain below where I saw the truck with Mokhtar sitting in its shade. 'This hill isn't nine thousand feet high.'

'Above sea level,' said Byrne. 'At Tarn we were four and a half thousand high, and we've been climbing ever since.' He rearranged his veil as he was always doing.

'What's this about a Hermitage?'

'Ever hear of Charles de Foucauld?'

'No.'

'Frenchman, a Trappist monk. In his youth, so I hear, he was a hellion, but he caught religion bad in Morocco. He took his vows and came out here to help the Tuareg. I suppose he did help them in his way. Anyway, most of what the outside world knows -. about the Tuareg came from de Foucauld.'

'When was this?'

'About 1905. He lived in Tarn then, but it wasn't much of a place in those days. In 1911 he moved here and built the Hermitage with his own hands. He was a mystic, you see, and wanted a place for contemplation.'

I looked at the barren landscape. 'Some place I'

'You'll see why when we get to the top. He didn't stay long – it damn near killed him; so he went back to Tarn and that did kill him.'

''How so?'

'In 1916 the Germans bribed the Libyan Sennousi to stir up trouble with the desert tribes against the French. The Tuareg of the Tassili n' Ajjer joined with the Sennousi and sent a raiding party against Tarn. De Foucauld was caught and shot with his hands bound – and it was an accident. An excitable kid of fifteen let a gun go off. I don't think they meant to kill him. Everyone knew he was a marabout – a holy man.' He shrugged. 'Either way he was just as dead.'

I looked at Byrne closely. 'How do you know all this?'

He leaned forward and said gently, 'I can read, Stafford.' I felt myself redden under the implied rebuke, but he laughed suddenly. 'And I talked to some old guys over in the Tassili who had been on the raid against Tarn in 1916. Some of the books I read sure are wrong.' He half-turned as if about to set off again, but stopped. 'And there was someone else in Tarn not long ago like de Foucauld – but a woman. English, she was; name of Daisy Wakefield. Said she was related to some English lord – something to do with oil. Is there a Lord Wakefield?'

There is.

'Then that must be the guy.'

'Did you know her?'

'Sure, Daisy and I got on fine. That's how I caught up with the news; she subscribed to the London Times. A mite out-of-date by the time it got here but that didn't matter.'

'What happened to her?'

'She got old,' he said simply. 'She went north to El Golea and died there, God rest her soul,' He turned. 'Come on.'

'Byrne,' I said. 'Why are we climbing this mountain?'

'To see a guy at the top,' he said without turning.

I trudged after him and thought: My God! Wakefield oil! This damned desert seemed littered with improbable people. In fact, I was following one of them. Maybe two, counting Paul Billson.

The building at the top of Assekrem was simple enough. Three small rooms built of stone. There were two men there who ushered us inside. They were dark-skinned men with Negroid features. Byrne said casually, 'Don't handle any of the stuff here; it's de Foucauld's stuff – holy relics.'

I looked about with interest as he talked with the men. There was a simple wooden table on which were some books, a couple of old-fashioned steel pens and a dried-out ink-well. In one corner was a wooden cot with an inch-thick mattress which looked about as comfortable as concrete. On a wall was a picture of the Virgin.

Byrne came over to me. 'Billson went through three days ago, I think. Or it could have been two days because another truck went through the day after, and I'm not sure which was Billson. But that truck came out again yesterday.'

'We didn't see it.'

'Might have gone out the other way – through Akar-Akar.' He rubbed his jaw reflectively and looked at me. I noticed he hadn't bothered to keep up his veil in the presence of these men. He said abruptly, 'I want to show you something frightening – and why de Foucauld built here.'

He turned and went outside and I followed. He walked across the natural rock floor of a sort of patio to a low stone parapet, and then pointed north. 'That's where your boy is.'

I caught my breath. Assekrem was a pimple on the edge of a plateau. Below the parapet were vertiginous cliffs, and spread wide was the most awe-inspiring landscape I had ever seen. Range after range after range of mountains receded into the blue distance, but these were none of your tame mountains of the Scottish Highlands or even the half-tamed Swiss Alps. Some time in the past there had been a fearsome convulsion of the earth here; raw rock had ripped open the earth's belly with fangs of stone – and the fangs were still there. There was no regularity, just a jumble of lava fields and the protruding cores of volcanoes for as far as the eye could see, festering under a brassy sun. It was killer country.

'That's Koudia,' said Byrne. 'The land beyond the end of the world.'