Nathan did all of these things, and as the work gradually slackened off even found time for a little local travelling and studying among the Thyre. And since the elders did not consider it fitting that a person of Nathan's importance should concern himself with the basic requirements of life, Atwei became his aide among the living just as Rogei was his spokesman among the dead. Dealing with all mundane matters, she left Nathan free to explore the possibilities of his unique talent.
In fact he was given too much freedom and failed to use it to his best advantage. For as the furious pace of his life slackened, so he allowed a host of dreams and memories of past, unbearable things to creep back in to plague him. He dreamed of Canker Canison's barking laugh as the loping dog-thing carried Misha away to the horror of some unthinkable future; and of his mother, a flame-eyed thrall in the service of a hideous vampire Lord; and of Nestor rotting in the river, a thing of weeds and sloughing grey flesh, dissolving into the mud. Nightmares such as these invariably brought Nathan gibbering awake, and Atwei would come running to comfort him..
In black bowels of earth beneath the colony, where even the fishermen of the Thyre must cast their nets by flaring torchlight, Atwei showed Nathan a section of the Great Dark River and explained as best she could its source and destination.
'As Sunside's rains roll down off the barrier mountains,' she said, her husky whisper echoing into the darkness and back from unknown places, 'and as storm-clouds burst less frequently over the furnace desert itself, so great bodies of water find their way underground. Many major tributaries may be found in the west, and others to the east, between the desert and the mountains. And so the Great Dark River under the earth is the sump of the world!
The hard bedrock of the underworld is tilted eastwards; likewise, naturally, the course of the river. Where the rocks are softest, the rain of centuries has formed many cavern systems. Of these, the safest and most suitable have become Thyre colonies. The underworld is as important to the Thyre as your forests are to you Szgany. Temperate, it provides shade from the sun in the heat of the long day, and is a refuge from the bitter chill of desert nights. We could not live without it, or without the river which is its dark lifeblood.
'During its life the river has carved wide ledges in the rock. Of these, the driest and safest are used as paths along which we may follow the water's course where it rushes through dark gullies. In parts the river is navigable over long miles, forming vast sunless lakes where the blind fishes swim; but in other places the way is tighter and the water roars furiously!
'As for its length: the river parallels the barrier mountains; it passes under the Great Red Waste, and meanders past a range of lesser mountains where dwell people much like yourself… or perhaps unlike yourself, for they give of their young to the Wamphyri. And so the river flows into the unknown. Some say it journeys to a sea far in the east, beyond the caverns of the necromancers; but this is rumour, because no one of the Thyre has ever been there.'
Nathan listened attentively to Atwei; he looked at the ledges carved by the river in the canyon walls of the channel through ages immemorial, at the blackly gurgling water flowing swiftly by, and the catches of the fishermen wriggling in their nets. And at one and the same time the river both repulsed and fascinated him. Merely to think of its sheer length was an awe-inspiring exercise in itself: more than three thousand miles of subterranean waterways, if Atwei was right, and Nathan was sure that she was. Why, Sunside's rivers were streams by comparison; the Great Dark River covered more miles than Nathan had seen in his entire life!
And yet it wasn't so much the river's size as its course which most affected Nathan's imagination: a course that followed the mountains east into that region beyond the Great Red Waste where the Wamphyri held sway, out of which they had returned into Starside. And as the river was a road to the Thyre, which they might follow on foot and by boat, colony to colony for all its many leagues, so might Nathan follow it…
Sunups came and went; Nathan's work in the Cavern of the Ancients neared completion; he told The Five that he planned to move on, and they swore him to secrecy. He promised that whatever the future held, he would never tell his brothers in the outside world what he had learned of the Thyre and their ways.
In the meantime his nightmares had got no better; if anything they were worse. Over and over Nathan lived through the hell of that night and morning in Settlement, the time of the Wamphyri raid. Also, he was aware of time fleeting by, and wondered how Lardis and the Szgany Lidesci fared now. Often in the Cavern of the Ancients he would sense his wolves trying to contact him. But they were distant and he was shielded by massive walls of rock; and anyway, what would they have to say except — it seemed likely — things he did not wish to hear? For by now, surely the Wamphyri were mighty again, a plague throughout all of Sunside.
Once (for once on his own), he fell asleep in the Cavern of the Ancients and dreamed that the numbers vortex waited for him. That mighty, bottomless whirlpool of figures tugged at him insistently; he felt that if only he knew the meaning of all of these rapidly mutating symbols.. they could open up whole new worlds to him. Any world would be better than the one he'd left behind, providing that it let him live among his own kind. And again he felt like a traitor who had turned tail and fled from his enemies, his friends, even from himself.
And now he must flee again, put greater distance between himself and the past, go searching for some shadowy fulfilment just around the corner of tomorrow…
In the Cavern of the Ancients he said his farewells. The dead were silent for a while. They would miss him.
But… he might return, one day? He couldn't say for definite, but possibly. Well, they had had their fair share of him, and the dead of other places were eager to meet him.
Nathan spoke to Shaeken. Working so much together, they had developed firm bonds, a warm friendship and understanding. And: 'In time, your works will be a blessing to the Thyre,' he told the great engineer.
They were nothing without you, Nathan, the other was flattered. But in a moment, and much more seriously: Nathan, these numbers which plague your dreams..
'Oh? You've been spying on me?' Nathan knew it wasn't so.
Hardly that! We can't help it. After all, you are the Necroscope. But the numbers: I've seen them, it's true. And as you know I have a small understanding of numbers.
'You understood the vortex?'
He sensed the shake of a head. Did I understand it? No. Was I afraid of it? Yes: even as a child fears the lightning! By comparison, my own calculations are ant tracks in the sand — quickly blown away — while yours are alive and work towards an end. And just as your deadspeak is unique among the living, so is the vortex yours alone. It is a part of you, Nathan! I'm no philosopher; my thoughts are shallow, mechanical things; but I sense that if one day you should fathom it, then you will be that much closer to your destiny. In Open-to-the-Sky there was upon a time an elder who was a mathematician. He is dead now, but what is that for a barrier? Perhaps you should seek him out.