Za scowled down at the ashes. 'My father made fire.'

Old Mother muttered, 'So he did - and he died for it.'

Za's father had gone hunting one day, and had never returned.

Such incidents were common enough. Often the beast was quicker or more cunning than the hunter. It kept the numbers of the Tribe low, and meant more food for those who lived.

'My father died hunting,' rumbled Za angrily.

'Gor was a great hunter. I never saw the beast that could destroy him. He angered the gods by making fire.'

Za stared at her in angry confusion. 'He taught me how to make the sharp stones for spears and axes. He taught me how to make traps for the bear and the tiger. He would have taught me how to make fire, if the beast had not killed him.'

'So that everyone would bow to you as they bowed to him,'

sneered Old Mother. But she knew Za spoke the truth. The secret of making fire was the most jealously guarded of all, handed down from chief to chief. Gor had hung on to the secret as long as he could - a full grown son can be a rival, too. He was always promising that one day soon he would teach Za how to make fire - but he died before the promise could be kept.

Now Za was chief, partly because he was Gor's son, more because he was the strongest warrior of the Tribe. But he still lacked the one magical attribute of a true chief - the ability to make the fire come from his hands into the wood. Suddenly, Za leapt to his feet, and loomed threateningly over Old Mother. 'Tell me what my father did to make fire!'

'He crouched over the wood, and moved his hands as you do.

But always, he kept his back turned, hiding the wood with his body. I never saw the moment when the fire came. That is all I know.'

'Ah, get out of my sight, old woman. You should have died with him.'

Old Mother rose and hobbled away. 'Fire is evil,' she muttered.

'Gor died because his pride angered the gods. It is better to live without fire, as we did in the old times.' She laughed triumphantly.

'The fire is gone now. Za will never make fire.'

Za was crouched over the pile of sticks again. 'Throw on more of the ashes of the dead fire,' he ordered. 'Perhaps the spirit of the fire still lives in them.'

Hur threw on more ashes, and Za went on gripping the charred sticks, striking them together, willing the fire to come. The girl Hur crouched at his side, her lips close to his ear. 'The old men talk against you, Za. They say it would be better for the stranger Kal to lead us. They say you sit all day rubbing your hands together, while Kal brings us meat.'

'Without meat we go hungry,' said Za. 'But without fire we shall die when the cold time comes again. Without fire, the beasts of the forest will raid our caves when they are hungry, steal our women and children while we sleep.'

'Old men see no further than the meat that fills their bellies.

They will make Kal the leader. And Horg, my father, will give me to him.'

Horg was one of the elders of the Tribe. He was old now, but he was still a man of great influence.

Since he was no longer the strongest, he would support the strongest. It was the law of survival.

'Kal!' said Za moodily. 'Kal is no leader. It is not so easy to be leader.'

Kal had appeared from over the mountains one day, sole survivor of some distant tribe that had perished in the great cold. He had brought the body of a newly killed buck with him as a peace offering. Kal was a fine hunter, a quick thinker and a great talker.

Instead of killing him, as was their custom with strangers, the Tribe had allowed him to join them. It had been, thought Za, a great mistake not killing Kal. By now, Kal had gathered a considerable following, and there were those who spoke of him for chief.

Za knew instinctively that Kal was no fit leader for the Tribe.

He was greedy and ruthless, wanting everything for himself. Za took the biggest share of the kill, and the warmest skins, as was his right, but he cared for the Tribe as well, seeing that hunting parties were organised, and that even in times of hardship the women and children were given food. A leader must think of many things.

'Kal is no leader,' muttered Za again.

Hur said, 'The leader is the one who makes fire!'

Za sent the pile of sticks flying with one sweep of his powerful arm. 'Where has the fire gone? Where?'

Ian Chesterton came back to consciousness with a bruised body and a throbbing head. Cautiously, he raised his hand and rubbed it over his scalp. There was a lump just above one ear. It was sore, but there didn't seem to be any blood.

A voice called, 'Ian? Ian are you all right?'

He opened his eyes and saw Barbara kneeling beside him.

'This is getting to be a habit,' he muttered. 'I'm all right, I think. Must have hit my head when...' He broke off as the memory of the evening's extraordinary events came flooding back. 'Well, at least we've stopped moving.' Ian got gingerly to his feet, looked round and saw Susan and the Doctor standing by the central console, studying one of the instrument banks.

'The base seems to be steady,' Susan was saying.

The Doctor nodded, checking another row of dials. 'Layer of sand, and thin topsoil - nearby rock formations... good... good...'

Susan turned, smiling at Ian and Barbara. 'Are you feeling better? We've left 1963, I'm afraid.'

The Doctor nodded in agreement. 'Oh yes, undoubtedly. I'll tell you where we are in a moment - and when!' The Doctor leaned over the console and rapped a dial sharply with his knuckles. 'Zero!' he said indignantly. 'Zero? That can't be right. This yearometer still isn't working properly, Susan.' He realised Susan hadn't been talking to him at all, followed the direction of her glance, and saw Ian and Barbara sitting on the floor. 'Oh, yes, you two!' he said airily, as if he'd just remembered their existence. 'What are you doing down there? You can get up now, our journey's finished.'

Barbara was staring at him in horror. 'What's happened?' she demanded. 'Where are we?' Ian struggled to his feet, groaning a little.

'Barbara, don't tell me they've got you believing all that nonsense.'

'It's true, Mr Chesterton,' said Susan, 'We've travelled a great distance in Space and in Time. Look at the scanner screen!'

The Doctor sniffed. 'That's right, look up there!' He pointed to a small square screen suspended above the console. It showed a bleak and rocky plain, the edge of what looked like a forest and a view of distant mountains.

As Ian stared at the screen in amazement, the Doctor said scornfully, 'They don't understand, and I suspect they don't want to!'

He looked at Ian. 'Well, there you are young man, a new world for you.'

'It's just sand,' said Ian stupidly. 'Sand and rocks.'

'Exactly. That's the immediate view outside the ship.'

'Are you trying to tell me that's what we'll see when we go outside - not the junk yard in Totters Lane?'

'Oh yes,' said Susan brightly. 'You'll be able to see for yourself soon.'

'I don't believe it,' said Ian flatly.

The Doctor sighed. 'You really are very stubborn, aren't you, young man?'

'All right, just you show me some proof, some concrete evidence.' Ian looked sympathetically at Susan. 'I don't want to hurt you, Susan, but it's time you were brought back to reality.'

'You're wrong, Mr Chesterton,' said Susan sadly.

The Doctor sniffed indignantly. 'He's saying I'm a charlatan!

Just what evidence would satisfy you, young man?'

'That's easy. Just open the doors, Doctor Foreman.'

'Foreman?' muttered the Doctor, as if he'd never heard the name before. 'Foreman? What's he talking about now?'