Wasteland of flint

obviously taken meticulous care of the ultralight. There were many signs of microfauna infection, but they had been cleaned and patched. Gretchen, for her part, took the time to clean all of the exposed surfaces with the magnetic sweeper. Then she surveyed the interior of the cabin with her goggles dialed up into ultra. Seems clean, she thought.

After stowing her baggage and prepping the ultralight for takeoff, Gretchen ran a test on the shipboard systems, including the cameras and the geosensing array Russovsky had added to the underside of the wings. Everything checked out. She amused herself for a few minutes with the cameras, zooming the viewfinders and seeing what kind of magnification they were capable of. They were of moderate quality, so she left them focused on the horizon in case something happened.

Gretchen climbed up into the wreck. The shuttle had been reduced to a skeleton of twisted metal and soot- blackened surfaces. A jumble of unidentifiable wreckage filled the interior, leaving no way to crawl inside. Every nook and cranny was filled with spidery stone filaments and tubelike extrusions. Anderssen grimaced at the mess, then climbed down and began to circle the debris, paying close attention to the hull surface.

Atmospheric shuttles were fitted with heat-ablative polyceramic sheathing. This one had been twisted and warped by the impact of the crash, stripping away long sections of the hex-shaped tiles, leaving them scattered across the sandy floor of the valley. Anderssen bent down and gingerly turned over one of the black hexagons. To her surprise, the underside of the composite was dusty but not eaten away or encrusted with the mineralization she'd come to associate with the microfauna.

'They don't eat everything,' she mused, picking up the tile. Under a rubbing fingertip, the ceramic came away clean and shiny. Gretchen frowned before realizing the composite would be designed for minimal air resistance as well as its heat-shedding properties. 'Huh. We could collect the whole set and make ourselves a house.'

Emboldened by this discovery, she took out an excavation tool and wedged the metal tip between a pair of tiles still attached to the wreck. Both tiles popped off, revealing a honeycombed, stonelike crust beneath. Gretchen drew back, but even the unaided eye could see the delicate filaments so-suddenly exposed to the bare sun wither and corrode. 'Sister! They're already eating away the hull.'

Her comm woke with a buzz and Hummingbird's harsh voice filled her ears.

'They are. The first storm of any magnitude will tear the sheathing away, scattering the tiles, and then there will be only dead stone.'

Gretchen turned, following the winking light of her directional finder and saw a tan and black shape climbing down the face of a long, low dune to her west. A line of footprints smudged the perfectly smooth face. 'Where have you been?'

'Two men survived the crash, one injured, one not,' the nauallis said, his breathing a little short with the effort of moving in sand. Gretchen could hear a background hiss of his rebreather and the hum of suit systems over the comm link. 'They went toward those hills.'

The distant figure raised an arm, pointing west.

'Did you find their bodies?' Gretchen continued to move along the edge of the wreck, turning bits of metal and plastic over with her tool. 'Or any sign they were picked up?'

'They found a cave at the edge of the hills. A deep cave. They did not come out.'

Anderssen clicked her teeth in amusement. 'You mean you didn't find any more tracks.'

'No.' Hummingbird's voice was still thready. 'The cave could have another exit, but I did not explore beyond the mouth. The floor was covered with minute bluish crystals – they were not disturbed beyond a certain point.'

'Hmm.' Gretchen had rounded the western side of the wreck and stood near the tents again, staring at the long scarlike furrow torn across the valley. 'These crystals only grow in shadow?'

'Yes.' The nauallis began to make better time, having descended the dune to the gravel-strewn floor of the valley. 'But there is enough space for two men to find shelter. How swiftly do these structures grow?'

'A good question, old crow.' Gretchen bent down and began to unstake the nauallis's pressure tent. 'If they have something to eat – and are protected from UV – you can watch them expand with the naked eye.'

There was a sigh on the comm, followed by an intermittent hissing sound. 'Then both men could have gone deeper into the cave and the crystals might have regrown, covering their tracks.'

'I suppose.' Gretchen made a face, examining the bottom of Hummingbird's tent. The reinforced floor was discolored and ragged. So much for impact-resistant microfiber. This looks worse than mine does, but it's been sitting here longer. At least a half-hour longer! Better figure out some way to sterilize the ground when we camp. Ah, I know! She stirred the sand with her boot, watching sparkling motes appear among the reddish grains, then disappear. 'We should make camp early each day,' she said in an offhand voice.

'Very well.' Hummingbird approached, striding easily across the hard-packed gravel. Gretchen looked him over and saw he'd managed to get his head scarf and cloak properly secured and draped. 'What are you doing with my tent?'

'Seeing how badly it's been damaged,' she said, dropping the rotting plastic back on the ground. 'Do you have a spare?'

Hummingbird shook his head as he came up. At close range, his eyes were only smudged shadows within the cowl of his kaffiyeh. 'What happened?'

'The sand is hungry. I guess it likes the taste of double-flex, single-porosity polymer.' Gretchen stifled a sigh and tried not to glare at the Nбhuatl. 'We'll have to double-bunk in mine. We'll keep yours as a ground cover for as long as the fabric lasts.'

The nauallis turned over the tent himself and Gretchen heard the hiss of an interrupted breathing tube again. 'I see,' Hummingbird said at last. 'What about the aircraft?'

'What about any of our equipment?' she snapped in annoyance. 'Everything we have is at risk. Are we leaving here today?'

The nauallis shook his head. 'There are some things I have to do first.'

'Get busy, then.' Gretchen felt a stab of worry, staring at the Midge landing gear. All three wheels were resting in the sand. Great, an inch of dust is dangerous. Well – if we land on solid rock, we should be safe. What are those wheels made of? I'd better find something to protect them with.

The day passed and grew hotter. The nauallis wandered around the wreckage in an aimless fashion, apparently ignoring the fierce, white-hot glare of the sun. Gretchen kept to the thin sliver of shade under the corroded, decaying wing of the shuttle. Her suit was insulated and cooled, but the thin atmosphere of Ephesus offered only meager protection against the radiation flooding down from the system primary. She amused herself by peeling hexagonal tiles from the skin of the shuttle. Each hex was cut with alternating tongues and grooves, allowing a secure fit between the sections.

Gretchen looked up, her attention drawn by a faint muttering sound. She felt disoriented and realized the sun had changed position noticeably, twisting the shadows cast by the wreckage and the boulders to the west. The quality of the air seemed different – though there was no single factor she could bring to mind to account for the feeling.

The nauallis passed by, facing into the sun. Hummingbird seemed to be limping, dragging his feet. Further, he was hunched over and swinging his arms as if he were weighed down by a tremendous weight.

'Crow? Are you all right?' Anderssen rose from her pile of black hexagons. An adhesive from her tool belt seemed to adhere to the ceramic, allowing her to make a series of meter square pads from the material. The first assembly was buried in sand at the base of the shuttle wing. She planned on excavating the offering in a couple of hours to see if the microfauna liked the taste of the bonding agent. 'Have you hurt your leg?'

There was no answer, only a faint hissing and chuckling sound on the comm link. Gretchen felt a queer, stomach-churning tension overtake her and jogged out into the sunlight. The nauallis had turned away, heading out along the line of the shuttle's impact. Despite his unsteady gait, Hummingbird made good time. Anderssen blinked in surprise – it seemed the Nбhuatl had suddenly leapt ahead, receding before her eyes. She began to run.

The nauallis shambled along the line of the skid, a long rough gouge in the sand and stony soil. He seemed to waver, weaving his body, kneeling, almost crawling on the ground, moving as if a wind