'I'm sorry to be so abrupt. You're very shocked. But I don't like long goodbyes or arguments, and I knew that that was what I'd get if I told you ahead of time.'

He paused, looked at their pale faces, and said, Tm staying here. I prefer this world to the one we left. That's all.'

He turned and pressed the button that opened the vault-like door and stepped outside. As he did so, the tribespeople cried out and some raced toward him. They must have guessed that he had decided to stay with them, and they were happy. At least, most of them were. No man ever lived that was one hundred per cent popular.

Rachel cried out, 'Stop him! Stop him!'

'With what?' Drummond said. He had recovered swiftly from his shock and seemed almost as joyous as the tribesmen. "We don't have any guns, and he wouldn't pay any attention to them if we did. And, as he said, he could take all three of us on and not even get up a sweat.'

He ran to the pile that was to be Gribardsun's substitute and picked up a bag of artifacts. 'You two had better help me, and quick!' he said. 'We haven't got much time!'

Rachel was weeping by now and she looked as if she would like to run after Gribardsun. But she picked up a bag, too, and walked to the vessel after Drummond. Von Billmann followed her with two sacks. He lowered them to the floor by the entrance and blocked her as she tried to get out again. Drummond pressed the button, and all three were quickly shut in again. They got into their chairs and strapped themselves in and waited.

On the screen they could see Gribardsun standing before the tribe. He lifted a hand in farewell.

Sixty-three seconds passed. And they were back in the twenty-first century. The vessel was forty yards from the edge of the hill, and the walls around the buildings of the project towered over them. Then figures clad in white helmets and suits, carrying tanks on their backs and hoses in their hands, stepped out of a small building on their right. The first phase of the quarantine had started.

Von Billmann answered the chief administrator. The eyes of the entire world were on them; everyone of the nine thousand, nine hundred and ninety-nine channels were devoted to the time vessel. But Rachel was paying no attention to the outside. She had dropped the recording ball, no larger than a child's marble, into the machine, and she was listening to John Gribardsun's voice.

Seven days later, the three were allowed to leave. The first thing they did was to go to the valley below, where the overhang still existed. Here they saw the hole in the back wall, broken open by the archeologists and project scientists. Behind six feet of rock was the chamber Gribardsun had promised they would find. And they also found the great stacks of artifacts and records that he said he planned to leave there, if he lived long enough.

Most of the records were in the form of John's handwriting on vellum and then on paper. But his last message, made in 1872, was recorded in a ball in one of the machines he had taken from the vessel.

'To you three, Robert, Drummond, and Rachel, it's only been a week, but to me, almost 14,000 years have passed. I have lived for more than that; I have lived far longer than seems right.'

'I did not think, the day I said goodbye forever to you, that I would live nearly this long. I am completely unafraid of death - which makes me somewhat nonhuman. I'm not afraid - but I also have a very strong will to live. Yet the mathematical probabilities of my living this long were very low. So many accidents can happen in 14,000 years; so many people and beasts would try to kill me. But they failed, and though I came near dying a number of times, I still live.'

'I still live. But for how long? Today is January 31, a Wednesday. Tomorrow, or sometime in the next few days, I'll be conceived.'

'Will Time tolerate two John Gribardsuns?

'Is there something in the structure of Time which win kill me? Or will I be erased from the fabric of Space-Time?

'I'll know only if I am spared. If I am killed or erased, I will be conscious one second and unconscious, because dead or obliterated, the next.

'Whatever happens, I can't explain. I have lived as no other man has lived, and for longer than any other man has lived.

'As you know now, I was fortunate enough to be given an elixir by a witch doctor who was the last man of his tribe. He belonged to a family the original head of which, some generations before, had discovered how to make the elixir, a vile-tasting devil's brew, from certain African herbs, blood, and several other constituents I will not even hint at. He had a high regard for me because I saved his life and also because he thought I was some sort of a demigod. He knew of my rather peculiar upbringing.

'But all that was explained on the ball I gave Rachel.

'How are you, Rachel? And you, Drummond? And you, Robert?

'Strange to speak to the unborn. I have gotten accustomed to speaking with the long dead. But the unborn - Well, I won't take up the valuable recording space in the ball to talk about the paradoxes of Time. That could go on and on.

'Robert, I know that the expedition of 8000 B.C. located your pre-Indo-Hittite speakers. I was one of the informants, None of the expedition suspected that I had already recorded the pre-I-H dialects in far more detail than they would ever be able to do with their limited time. And they were looking for me, too. I suppose they were looking for me because of this message. But they failed. I won't tell you why, of course, because then the expedition would be able to identify me. Ever if, in a sense, the expedition has already occurred. Well, I said I'd not get into the paradoxes.

'You'll find, Robert, that your pre-Indo-Hittite speech of 8000 B.C. arose from the very last place you would have, suspected.

'Our two tribes, the Wota'shaimg and the Shluwg, eventually abandoned their original tongues and adopted the pidgin. The result was a simple analytical system. But over the course of six millennia, it became a polysyllabled synthetic speech which eventually developed into the pre-Indo-Hittite the second expedition studied. And this, of course, became the Germanic, Balto-Slavic, Indo-Iranian, Greek, Italic, Celtic, and a dozen other language families which were not recorded or even heard of by civilized peoples. Until now.'

Gribardsun chuckled and said, 'So if it hadn't been for time travel, Robert, Indo-Hittite, and hence, German, Yiddish, English, French, and all those other related tongues would never have existed.

'Yes, I know you're going to say that our tribes had different blood groups than the Indo-Hittite speakers. But many invasions - migrations, rather - occurred from the East, and our tribe, which had become rather large between 12,000 B.C. and 8000 B.C., absorbed so many of the newcomers, and imposed their language on so many, that the original blood group was largely lost.'

Von Billmann had turned pale shortly after Gribardsun started talking. He sat down. He seemed to be having trouble getting his breath. Rachel brought him a drink of water, and he sat up and looked around as if he hoped someone had strength to give him.

'Do you realize what he's saying? I won't be on the 8000 B.C. expedition! But why? Was I dead before it could be launched? Or - why?'

Anderson, the project head, turned on the recorder again, since no one could give an answer and they did not want to dwell on the subject.

'There was one other expedition, that which was sent in 3500 B.C. to the Mesopotamian area. The others that had been planned were not realized. I waited for them, but they did not show. I wonder why. Something catastrophic prevented them? I don't know, and you, of course, won't know why until it happens.

'Be that as it may, here are the collections I made. The expedition would never have been made if it had not been for me, as you now know. But I still feel a sense of obligation to the people who gave me this chance to live when the world was fresh. And I have had so much scientific training that I do appreciate what this collection will mean. So, throughout the millennia, I have cached artifacts and specimens and made notes. There are at least a hundred thousand photographs here, since I kept back some of the balls for this purpose. You will find photographs, surreptitiously taken, of course, of the original historical Hercules - myself - Nebuchadnezzar, the historical Moses - not myself - Julius Caesar, Shakespeare, Eric the Red, whom I took from behind a bush, having been waiting for six months for him to land, the historical Odysseus, the real city of Troy, the first Pharaoh, several of the first emperors of China and Kublai Khan and Marco Polo. There are also photos of the historical Jesus, Gautama, and Mohammed, Charlemagne, Saladin, the historical Beowulf, a group photograph of the actual founders of the city of Rome. No Romulus and Remus existed, I am sorry to say. 'I could go on, but you'll find everything catalogued. 'I was a merchant-ship captain supplying the Achaean army, and I am mentioned in Homer, though not exactly in the role of a merchant. But I stayed away from the fighting there, as I stayed away from most fighting. As I stayed away from most centers of civilization. I decided that if I was going to survive for a long time, I would have to live a backwoods, backcountry life. I spent altogether a thousand years in the wilds of Africa and another in Asia and the pre-Columbian Americas, though not in a continuous stretch, of course.