'Fishermen are the same everywhere,' Taita remarked, but he made

appropriate sounds of amazement. Poto seemed neglected by his tribe and, for once, had the attention of all. He was enjoying the company of his new friends.I 'Why did your tribe leave such good fishing grounds?' Taita asked.

'Another stronger and more numerous people came from the east and we could not resist them. They drove us northwards along the river to this place.' He looked downcast for a moment, then brightened again.

'When I was initiated and circumcised, my father took me to the great waterfall that is the birthplace of this, our river.' He indicated the Nile on whose banks they sat. 'The waterfall is called Tungula Madzi, the Waters that Thunder.'

'Why such an unusual name?'j 'The roar of the falling waters and the mighty rocks they bring crashing down can be heard from a distance of two days' march. The spray stands above the falls like a silver cloud in the sky.'

'You have looked upon such a sight as this?' Taita asked, and turned his Inner Eye upon the ancient.

'With these very eyes!' Poto cried. His aura burnt brightly, like the flame of an oil lamp before it dies from lack of fuel. He was telling the truth.

'You believe that this is the birthplace of the river?' Taita's pulse raced with excitement.

'On the ghost of my father, the falls are where the river rises.'

'What lies above and beyond them?'

'Water,' said Poto flatly. 'Nothing but water. Water to the ends of the world.'¦ 'You saw no land beyond the falls?'™ 'Nothing but water.'

'You did not see a burning mountain that sends a cloud of smoke into the sky?'I 'Nothing,' said Poto. 'Nothing but water.'

'Will you lead us to this waterfall?' Taita asked.

When Nakonto translated the question to him, Poto looked alarmed.

'I can never return. The people thereabouts are my enemies, and they will kill me and eat me. I cannot follow the river because, as you can see, the river is cursed and dying.'

'I will make you a gift of a full bag of glass beads if you come with us,'

Taita promised. 'You will be the richest man in all your tribe.'

Poto did not hesitate. He had turned the colour of ashes and was trembling with terror. 'No! Never! Not for a hundred bags of beads. If

they eat me, my soul will never pass through the flames. It will become a hyena and wander for all time in the night, eating rotting carcasses and offal.' He made as if to jump up and run, but Taita restrained him with a gentle touch, then exerted his influence to calm and reassure him. He let him drink two large swallows of beer before he spoke to him again.

'Is there another who will guide us?'

Poto shook his head vigorously. 'They are all afraid, even more than I am.'

They sat in silence for a while, then Poto began to fidget and shuffle his feet. Taita waited patiently for him to reach some difficult decision.

At last he coughed, and spat a large clot of yellow mucus into the dust.

'Perhaps there is somebody,' he ventured. 'But, no, he must be dead. He was an old man when last I saw him, and that was long ago. Even then he was older than you, revered elder.' He bobbed his head respectfully at Taita. 'He is among the last of our people who remain from the time that we were a tribe of consequence.'

'Who is he? Where will I find him?' Taita asked.

'His name is Kalulu. I will show you where to find him.' Again Poto began to draw with his toe in the dust. 'If you follow the great river, which is dying, you will come at last to where it meets one of the many lakes. This is a mighty stretch of water. We call it Semliki Nianzu.' He drew it as an elliptical flattened circle.

'Is it here that we will find the waterfall that is the birthplace of the river?' Taita demanded.

'No. The river cuts through the lake like the head of a spear through the body of a fish.' He slashed his toe through the circle. 'Our river is the outlet, the inlet is on the far south bank of the lake.'

'How will I find it?'

'You will not, unless somebody like Kalulu leads you to it. He lives in the marshes, on a floating island of reeds on the lake. Near the outlet of the river.'

'How will I find him?'

'By searching diligently and by good fortune.' Poto shrugged. 'Or perhaps he will find you.' Then, almost as an afterthought, he added, 'Kalulu is a shaman of great mystical powers, but he has no legs.'

When they left the village Taita gave Poto a double handful of glass beads and the old man wept. 'You have made me rich, and my old age happy. Now I can buy two young wives to look after me.'

The Nile flowed a little more strongly as they moved south along its bank, but they could tell from the high-water line that the level was much lower than it had been in former times.

'It has shrunk twenty-fold,' Meren calculated, and Taita agreed, even though he did not say so. Sometimes Meren had to be reminded that he was not an adept, and that some matters were better left to those qualified to deal with them.

As they journeyed along the west bank, horses and men grew stronger with each day that passed. They were all fully recovered from the effects of the fly by the time they reached the lake, which was as Poto had described it to them. It was vast.

'It must be a sea, not merely a lake,' Meren declared, and Taita sent him to fetch a pitcher of water from it.

'Now taste it, my good Meren,' he ordered. Gingerly Meren took a sip, and let it run round his mouth. Then he drank the rest of the pitcher.

'Salt sea?' Taita smiled kindly.

'Nay, Magus, sweet as honey. I was mistaken, and you were right.'

The lake was so large that it seemed to create its own wind system.

In the dawn the air was still and cool. What looked like smoke rose high into the air from the surface. The men discussed this animatedly.

'The water is heated by a volcano,' said one.

'No,' said another. 'The water rises like mist. It will fall again elsewhere as rain.'

'Nay, it is the fiery breath of a sea monster that lives in the waters,'

Meren said with authority.

In the end they looked at Taita for the truth.

'Spiders,' said Taita, which threw them into further passionate argument.

'Spiders do not fly. He means flies - dragon flies.'

'He toys with our credibility,' said Meren. 'I know him well. He loves his little jokes.'

Two days later the wind veered and one of the cloudy up-wellings drifted over the camp. Then as it reached land it began to descend. Fenn leapt high in the air and snatched something out of it.

'Spiders!' she squealed. 'Taita is never wrong.' The cloud was formed by countless newly hatched spiders, so immature as to be almost transparent.

Each had woven a gossamer sail, which it used to catch the dawn breeze and sail aloft to be transported to some new quarter of the lake.

As soon as the sun struck the surface the wind picked up, until by noon it was whipping the water to foaming frenzy. During the afternoon it subsided until, at sunset, all was calm and serene. Flights of flamingoes strung out along the horizon in wavy pink lines. Hippopotamuses wallowed like granite boulders, grunting and bellowing in the shallows, cavernous pink jaws gaping to threaten rivals with their long incisors. Mighty crocodiles stretched out on the sandbars, sunning themselves, holding their mouths wide open so that water birds could pick the scraps of flesh from between their stubby yellow fangs. The nights were still, with the stars reflected on the velvety black waters.

To the west the lake was so extensive that there was no sight of land, other than a few small islands that seemed to sail like dhows on the wind-torn surface. To the south, they could just make out the far shore of the lake. There were no high mountain peaks or volcanoes, just a blue tracing of low hills.