Tightened the strings. He stuffed that pouch into the next smaller and followed by forcing that one into the small belt-pouch, which he tied at his waist. Inconvenient, though temporary. He would have no quick access to his weapons should some calamity arise, at least for the duration of the descent. Not that he could fight clinging like a drunk goat to the cliff-side in any case.

He made his way to the chute and looked over the edge. Icarium was making swift progress, already fifteen or more man-heights down.

What would they find down there? Rocks. Or something that should have remained buried for all time.

Mappo began his descent.

Before long, the passage of the sun swept all light from the crevasse.

They continued in deep gloom, the air cool and stale. There was no sound, barring the occasional scrape of Icarium's scabbard against stone from somewhere below, the only indication that the Jhag still lived, that he had not fallen, for, had he lost his grip and plummeted, Mappo knew that he would make no outcry.

The Trell's arms were getting tired, the calves of his legs aching, his fingers growing numb, but he maintained his steady pace, feeling strangely relentless, as if this was a descent with no end and he was eager to prove it, the only possible proof being to continue on. For ever. There was something telling in that desire, but he was not prepared to be mindful of it.

The air grew colder. Mappo watched the plumes of his breath frosting the stone face opposite him, sparkling in some faint, sourceless illumination. He could smell old ice, somewhere below, and a whisper of unease quickened his breathing.

A hand on the heel of his left, down-reaching foot startled him.

'We are here,' Icarium murmured.

'Abyss take us,' Mappo gasped, pushing away from the wall and landing with sagging legs on a slick, slanted floor. He flung his arms out to regain balance, then straightened. 'Are you certain? Perhaps this slope is but a ledge, and should we lose our footing-'

'We will get wet. Come, there is a lake of some sort.'

'Ah, I see it. It… glows…'

They edged down until the motionless sweep of water was before them. A vague, greenish-blue illumination, coming from below, revealed the lake's depth. They could see to the bottom, perhaps ten man-heights down, rough and studded with rotted tree stumps or broken stalagmites, pale green and limned in white.

'We descended a third of a league for this?' Mappo asked, his voice echoing, then he laughed.

'Look further in,' Icarium directed, and the Trell heard excitement in his companion's tone.

The stumps marched outward four or five paces, then stopped. Beyond, details indistinct, squatted a massive, blockish shape. Vague patterns marked its visible sides, and its top. Odd, angular projections reached out from the far side, like spider's legs. The breath hissed from Mappo. 'Does it live?' he asked.

'A mechanism of some sort,' Icarium said. 'The metal is very nearly white, do you see? No corrosion. It looks as if it had been built yesterday… but I believe, my friend, that it is ancient.'

Mappo hesitated, then asked, 'Is it one of yours?'

Icarium glanced at him, eyes bright. 'No. And that is the wonder of it.'

'No? Are you sure? We have found others-'

'I am certain. I do not know how, but there is no doubt in my mind.

This was constructed by someone else, Mappo.'

The Trell crouched down and dipped his hand into the water, then snatched it back. 'Gods, that's cold!'

'No obstacle to me,' Icarium said, smiling, the polished lower tusks sliding into view.

'You mean to swim down and examine it? Never mind, the answer is plain. Very well, I shall seek out some level ground, and pitch our camp.'

The Jhag was tugging off his clothes.

Mappo set off along the slope. The gloom was sufficiently relieved by the glowing water that he was able to make certain of each step he took, moving up until his left hand was brushing the cold stone wall.

After fifteen or so paces that hand slipped into a narrow crack, and, upon regaining contact, immediately noted a change of texture and shape in the surface under his blunt fingertips. The Trell halted and began a closer examination along its length.

This stone was basalt, ragged, bulging out until the slope beneath his feet dwindled, then disappeared. Sharp cracks emanated out across the angled floor and into the lake, the black fissures reappearing on the lake's bottom. The basalt was some kind of intrusion, he concluded.

Perhaps the entire crevasse had been created by its arrival.

Mappo retreated until he had room to sit, perched with his back against the rock, eyes on the now rippled surface of the lake. He drew out a reed and began cleaning his teeth as he considered the matter.

He could not imagine a natural process creating such an intrusion.

Contrary as earth pressures were, far beneath the land's surface, there was no colliding escarpment shaping things in this part of the subcontinent.

No, there had been a gate, and the basalt formation had come through it. Catastrophically. From its realm… into solid bedrock on this world.

What was it? But he knew.

A sky keep.

Mappo rose and faced the ravaged basalt once more. And that which Icarium now studies at the bottom of the lake… it came from this. So it follows, does it not, that there must be some sort of portal. A way in. Now he was curious indeed. What secrets lay within? Among the rituals of inculcation the Nameless Ones had intoned in the course of Mappo's vow were tales of the sky keeps, the dread K'Chain Che'Malle fortresses that floated like clouds in the air. An invasion of sorts, according to the Nameless Ones, in the ages before the rise of the First Empire, when the people who would one day found it did little more than wander in small bands – not even tribes, little different, in fact, from mortal Imass. An invasion that, in this region at least, failed. The tales said little of who or what had opposed them. Jaghut, perhaps. Or Forkrul Assail, or the Elder Gods themselves.

He heard splashing and peered through the gloom to see Icarium pull himself, awkwardly, onto the strand. Mappo rose and approached.

'Dead,' Icarium gasped, and Mappo saw that his friend was racked with shivers.

'The mechanism?'

The Jhag shook his head. 'Omtose Phellack. This water… dead ice.

Dead… blood.'

Mappo waited for Icarium to recover. He studied the now swirling, agitated surface of the lake, wondering when last that water had known motion, the heat of a living body. For the latter, it had clearly been thirsty.

'There is a corpse inside that thing,' the Jhag said after a time.

'K'Chain Che'Malle.'

'Yes. How did you know?'

'I have found the sky keep it emerged from. Part of it remains exposed, extruding from the wall.'

'A strange creature,' Icarium muttered. 'I have no memory of ever seeing one before, yet I knew its name.'

'As far as I know, friend, you have never encountered them in your travels. Yet you hold knowledge of them, nonetheless.'

'I need to think on this.'

'Yes.'

'Strange creature,' he said again. 'So reptilian. Desiccated, of course, as one would expect. Powerful, I would think. The hind limbs, the forearms. Huge jaws. Stubby tail-'

Mappo looked up. 'Stubby tail. You are certain of that?'

'Yes. The beast was reclined, and within reach were levers – it was a master of the mechanism's operation.'

'There was a porthole you could look through?'

'No. The white metal became transparent wherever I cast my gaze.'

'Revealing the mechanism's inner workings?'

'Only the area where the K'Chain Che'Malle was seated. A carriage of some sort, I believe, a means of transportation and exploration… yet not intended to accommodate being submerged in water; nor was it an excavating device – the jointed arms would have been insufficient for that. No, the unveiling of Omtose Phellack caught it unawares.