This was not like the Desert of No Return, not even like the western deserts they had crossed early in the journey. This was a featureless plain of gravel, dry clay, and a dusty, yellowish sand that tasted salty when it blew into your mouth. At night the stars made a tremendous dome, slowly swivelling towards the dawn. Though it was ferociously hot during the day, in the morning it could be cold enough to leave a frost that the animals licked from their blankets. Aside from the frost the only water, rarely glimpsed in almost dried-up streams, was brackish; even the horse and mule turned away from it. Sometimes a storm would blow up – wind, never rain – and the sand would take to the air, swirling around them, the particles stinging their faces and eyes, sometimes so violent they couldn’t make progress at all and they had to huddle in the small tent they had bought in Lop. But then the storms would blow away, and they would move on. They would find the wind had scraped away the earth down to a polished bedrock, and heaped the sand up in dunes like waves on an ocean.

So the next day passed, and the next. Often a day would pass with no landmarks at all, save a shallow dune or two: no mountains looming, no oases. Nothing to see but level sands stretching to the horizon, and the huge sky above. Gradually Avatak lost his sense of time and place, in this land like a dusty tabletop.

Pyxeas had him keep the journal, scratching in the date, and random observations and speculations. ‘Perhaps this was once a lake, or a sea,’ Pyxeas rasped. ‘A sea that somehow drained away. That would explain the flatness, and the salt. But where are the fish bones, and the wrecks of fishermen’s boats?’ And he would mumble and mutter, and subside back to his habitual state of half-sleep. Avatak did not care where the salt had come from. He made Pyxeas’ notes, but they were another man’s thoughts expressed in another man’s language; with a little practice he found he could ignore their meaning altogether, even as he wrote them down.

Still they walked, day after day, across a world reduced to its absolute essentials, to land below, sky above. ‘We walk through Pythagorean dualities,’ Pyxeas said. Avatak’s mind seemed to become as big as the sky, as if trying to fill all that empty space above, yet his spirit was diminished, to become a grain of sand as trivial as those under his feet. Was this how it was to die? To shrink into oneself, to shrivel to nothing, to become a dust speck in a universe grand and ancient that would continue without him, indifferent?