'From here on,' Hamilton said, 'no talking. Not one word. And watch where you put your feet. I don't want to hear as much as the crackle of a broken twig. Understood?' He looked at Maria, who looked pale and exhausted, not so much from the rigours of the walk, for there had been none, but because she had not slept at all: the previous night's experience, as Ramon had said, had been something more than traumatic.

'It's not much further. Half an hour, at most, then we'll have a rest and carry on during the afternoon.'

'I'm all right,' she said. 'It's just that I'm beginning to hate this rainforest. I suppose you'll be telling me again that no-one asked me to come.'

'A snake on every tree, is that it?' She nodded. 'No more worry,'

Hamilton said. 'You'll never again spend a night in the forest. That's another promise.'

Tracy said slowly: 'I take it that that can mean only one thing. I take it that we'll be in the Lost City tonight.'

'If things go as I hope, yes.'

'You know where you are?' 'Yes.'

'You've known ever since we left the hovercraft.'

'True. How did you know?'

'Because you haven't used your compa.s.s since.'

Half an hour later, exactly as he had forecast, Hamilton, finger to his lips, stopped and waited for the others to come up to him. When he spoke, it was in a whisper.

'On your lives. Not a sound. Stay hidden until I tell you otherwise. On your hands and knees then lie p.r.o.ne until I give the word.'

And so on hands and knees they advanced in total silence. Hamilton dropped forward and eased himself slowly ahead, using elbows and toes.

He stopped again and waited until the others had joined him. He pointed forward, through the trees. Irr a lush green valley below them they could see an Indian village. There were dozens of large huts and, in the centre, a very large communal hut, which looked as if it could accommodate at least two hundred people with ease. The place seemed to be deserted until suddenly a small copper-coloured child appeared carrying a flint axe and a nut which he placed on a flat stone and proceeded to belabour. It was like a scene from the Stone Age, from the dawn of prehistory. A laughing woman, statuesque and also copper-coloured, emerged from the same hut and picked up the child.

In slow wonderment, Tracy said: 'That colour? That appearance? Those aren't Indians.'

'Keep your voice down,' Hamilton said urgently. 'They're Indians all right but they do not come from the Amazon basin. They come from the Pacific.'

Tracy stared at him, still in wonderment, and shook his head.

Suddenly people, scores of them, began to emerge from the communal hut.

That they were not Amazonian Indians was obvious from the fact that there were as many women as men among them: normally, in the Amazonian basin, women are banned from the meeting places of elders and warriors.

All were of the same copper colour, all possessed of a proud, almost regal bearing. They began to disperse towards their huts.

Smith touched Hamilton on the arm and said in a low voice: 'Who are those people?'

'The Muscias.' Smith turned pale.

'G.o.dd.a.m.ned Muscias!' he said in a vicious whisper. 'What the h.e.l.l are you playing at? Head-hunters, you said. Head-shrinkers! Cannibals! I'm off!'

'Off where, you clown? You've got no place left to run to. Stay here.

Don't, don't, don't show yourselves.'

The advice was probably superfluous. No-one, clearly, had the slightest intention of showing himself.

Hamilton rose and walked confidently into the clearing. He had gone at least ten paces before he was noticed. There was a sudden silence, the babble of voices ceased, then the chatter redoubled in volume. An exceptionally tall Indian, old and with his forearms almost covered in what were unquestionably gold bracelets, gazed for some seconds then ran forward. He and Hamilton embraced each other.

The old man, who was surely the chief, and Hamilton engaged in an animated, if incomprehensible, conversation. The chief, with an expression of incredulity on his face, repeatedly shook his head. Just as firmly Hamilton nodded his. Suddenly, Hamilton extended his right arm and made a semi-circular motion, bringing his arm to a sudden halt. The chief looked long at him, seized him by the arms, smiled and nodded his head. He turned and spoke rapidly to his -people.

Tracy said: 'I'd say those two people have met somewhere before.'

The chief finished addressing his people, all of whom had now gathered in the clearing, and spoke again to Hamilton, who nodded and turned.

Hamilton shouted to his waiting companions: 'You can come now. Keep your hands well away from any weapon.'

Not quite dazedly, but not understanding what was happening, the other eight members of the party entered the clearing.

Hamilton said: 'This is Chief Corumba.' He introduced each of the eight in turn. The chief gravely acknowledged each introduction, shaking each in turn by hand.

Hiller said: 'But Indians don't shake hands.'

'This Indian does.'

Maria touched Hamilton on the arm. 'But those savage head-hunters --'

'These are the kindliest, most gentle, most peaceable people on earth. In their language they do not have a word for war because they do not know what war is. They are a lost children from a lost age and the people who built the Lost City.'

Serrano said: 'And I thought I knew more about the tribes of the Mato Grosso than any man alive.'

'And so you may, Serrano, so you may. If, that is to say, I can take the word of Colonel Diaz.'

'Colonel Diaz?' Smith said. He was clearly floundering in deep water.

'Who's Colonel Diaz?'

'A friend of mine.'

Tracy said: 'But their ferocious reputation --'

'A fiction invented by Dr Hannibal Huston, the man who found these lost people. He thought that such a reputation might ensure them -- what shall we say? -- a little privacy.'

'Huston?' Hiller said. 'Huston? You - you found Huston?'

'Years ago.'

'But you've only been in the Mato Grosso for four months.'

'I have known it for many years. Remember in the Hotel de Paris in Romono you mentioned my search for the golden people? I forgot to mention that I also met them years ago. Here they are. The Children of the Sun.'

Maria said: 'And Dr Huston is still in the Lost City?'

'He's still there. Come, I believe these good people want to offer us some hospitality. First, however, I owe you a small explanation about them.'

'High time, too,' Smith said. 'Why all the dramatic, stealthy approach to them?'

'Because if we had approached as a group they would have run away. They have every good reason to fear those from the outside world. We, ironically known as the civilizados -- in practically everything that matters they're a d.a.m.ned sight more civilised than we are -- bring them so-called .progress, which harms them, so-called change, which harms them, so-called civilisation, which harms them even more, and disease, which kills them. These people have no natural resistance to measles, or influenza. Either of those are to them what bubonic plague was to Europeans and Asiatics in the Middle Ages. Half a tribe can be wiped out in a fortnight. The same thing happened to the people of Tierra del Fuego. Well-meaning missionaries gave them simple clothes, primarily so that the women could cover their nakedness. The blankets came from a hospital where there had been a measles epidemic. Most of the people were wiped out.'

Tracy said: 'But our presence here. Surely that endangers them?'

'No. Almost half the Muscias were destroyed by measles or influenza or a combination of both. These people here are the survivors, having acquired natural immunity the hard way. As I said, it was Dr Huston who found them. Although mainly famous as an explorer, his real life's work lay elsewhere. He was one of the original sertanistas -- men wise in jungle ways -- and a founder member of the FUNAI, the National Foundation for the Indian, people who dedicate their lives to protecting the Indians and rendering them harmless to civilizados. "Pacification" is the term generally used but in truth what they mainly required was protection against the civilizados. Sure, many of the tribes were genuinely savage -- well, not so many, there are less than two hundred thousand pure-blood Indians left -- but their savagery sprang from fear and very understandably so. Even in modern times, those civilised gentlemen from the outer world, and by no means all Brazilians, either, have machine-gunned them, dynamited them from the air and given them poisoned food.'

'This is all news to me,' Smith said, 'and I've lived in this country for many years. Frankly, I find it very hard to believe.'

'Serrano will confirm it.'

'I confirm it. I take it that you, too, are a sertanista.'

'Yes. Not always a very happy job. We have our failures. The Chapate and the h.o.r.ena, as you've seen, are not too keen on the idea of co-operation with the outside world. And, inevitably, we bring disease as we did here. Come along, Chief Corumba is summoning us to eat. It may taste a little odd, but I can a.s.sure you that no harm will come to any of you.'

One hour later the visitors were still seated around a rough wooden table outside the communal hut. Before them lay the remains of an excellent if rather exotic meal -- game, fish, fruit and other unknown delicacies concerning the nature of which it had been thought more prudent not to ask: all had been washed down with cacha.s.sa, a rather potent brew. At the end, Hamilton thanked Chief Corumba on behalf of all of them and turned to the others. 'I think it's time we were on our way.' Tracy said: 'One thing intrigues me. I've never seen so many gold ornaments in my life.' 'I thought that might intrigue you.' 'Where do these people come from?' 'They don't know themselves. A lost people who have lost everything and that includes their history. It was Dr Huston's theory that they are the descendants of the Quimbaya, an ancient tribe from the Cauca or Magdalena valleys in the western Andes of Colombia.'

Smith stared at him. 'So what in G.o.d's name are they doing here?'

'n.o.body knows. Huston thinks they left their homeland all those hundreds of years ago. He thinks they may have fled to the east, found the head-waters of the Amazon, come all the way down until they reached the Rio Tocantis, turned up that until they came to the Araguaia, then up the Rio da Morte. Again, who knows? Stranger migrations have happened. It could have taken them generations: they were weighed down with many possessions. I believe it. Wait till you see the Lost City and you'll understand why I do believe it.'

Smith said: 'How far away is this d.a.m.ned city?'

'Five hours. Six.'

'Five hours!'

'And easy going. Uphill, but no swamps, no quicksands.' He turned to Chief Corumba, who smiled and again warmly embraced Hamilton.

'Wishing us good luck?' Smith said.

'Among quite a few other things. I'll have a longer chat with him tomorrow.'

'Tomorrow!'

'Why ever not?'

Smith, Tracy and Hiller exchanged flickering glances. None of the three said anything.

Just before they walked away Hamilton spoke-quietly to Maria. 'Stay behind with these people. They will look after you, I promise. Where we're going is no place for a lady.'

'I'm coming.'

'Suit yourself. There's an excellent chance you'll be dead by nightfall.'

'You don't much care for me, do you?'

'Enough to ask you to stay behind.'

In the late afternoon Hamilton and his party were still making their way towards the Lost City. The going underfoot was excellent, dry, leafy and springy.

Unfortunately for people like Smith, the incline was fairly severe and the heat was, of course, as always oppressive.

Hamilton said: 'I think we'll have a half-hour break here. We're ahead of time -- we can't move in until it's dark. Besides, some of you may think you've earned a rest.'

'Too b.l.o.o.d.y right, we have,' Smith said. 'How much longer do you intend to crucify us?'

He sank wearily to the ground and mopped his streaming face with a bandana. He was not the only one co do so. With the exception of Hamilton and the twins, everyone seemed to be suffering from a shortage of breath and leaden, aching legs. Hamilton had, indeed, been setting a brisk pace.

'You've done very well, all of you,' Hamilton said. 'Mind you, you might have done even better if you hadn't guzzled and drunk like pigs down in the village. We've climbed almost two thousand feet since leaving there.'

Smith said: 'How -- much -- longer?'

'From here to the top? Another half hour. No more. I'm afraid we'll have to do a bit more climbing after that -- downhill, mind you, but a pretty steep downhill.'

'Half an hour,' Smith said. 'Nothing.'

'Wait until you start going down.'

'The last lap,' Hamilton said. 'We are ten yards from the brink of a ravine. Anyone who hasn't a head for heights had better say so now.'

If anyone didn't have a head for heights he or she wasn't saying so.

Hamilton began to crawl forward. The rest followed. Hamilton stopped and motioned to the others to join him.

Hamilton said: 'You see what I see?'

Smith said: 'Jesus!'

Maria said: 'The Lost City!'

Tracy said: 'Shangri-la!'

'El Dorado,' Hamilton said.

'What?' Smith said. 'What was that?'

'Nothing, really. There never was an El Dorado. It means the golden man.

New Inca rulers were covered in gold dust and dipped -- only temporarily, of course -- in a lake. You see that peculiar stepped pyramid with the flat top at the far end?'

The question was really unnecessary. It was the dominant feature of the Lost City.

'That's one of the reasons -- there are two others - why Huston thought that the Children of the Sun came from Colombia. It's what you call a ziggurat. Originally it was a temple -- tower in Babylonia or a.s.syria.

No traces of those remain in the Old World -- the Egyptians built a quite different form of pyramid.'