Terry Pratchett - The Long Mars

Frank said, ‘And the elevator?’

‘Maybe they moved the root station here, before the end, from Pavonis or wherever else. Kind of romantic, but very long-term thinking. They lived in a hole in the ground to make sure they saved their air and water, but they kept their ladder to the planets.’

Sally peered into the pit. ‘So what’s down there now?’

‘Life,’ said Willis. ‘I can tell that much. There’s oxygen, methane – the atmosphere is unstable, chemically. So something must be photosynthesizing away, pumping all that oxygen into the air.’ He glanced around, at the way the slanting morning sunlight caught only the upper surface of the pit walls. ‘No, not photosynthesis. Not primarily anyhow – not enough direct light, in the depths. Maybe it’s like the deep-sea organisms on Earth, out of sight of sunlight, feeding on seeps of minerals and energy from underground. We’re close enough to the Tharsis volcanoes for that to work; the big magma pockets under those babies must leak a lot of heat.’

Sally asked, ‘So this is the last refuge of their civilization. Where’s the city lights, car exhausts, radio chatter?’

‘None of that, I’m afraid. There is one splash of metal.’

Frank looked startled. ‘Metal?’

‘An irregular form. Down on the floor of the pit.’

Sally said wistfully, ‘All this makes me think of Rectangles.’

Willis wasn’t interested, but Frank glanced at her. ‘Where?’

‘A Long Earth world I discovered with Lobsang and Joshua. We called it Rectangles, for the traces of foundation ruins we found on the ground. Another site with relics of a vanished civilization.’

‘Right. And a cache of high-tech weapons.’

She looked at Frank in surprise. ‘How did you know that? Oh. Jansson told you.’

‘We spoke a lot. Especially when she was in her last days, during Yellowstone. Told me a lot about her life. Her time with you—’

‘We’ll have to go down,’ Willis said, cutting across their talk. ‘Into the hole.’

Sally took a breath. ‘I was afraid you’d say that.’

‘In the spirit of noble exploration, I suppose,’ Frank said.

‘No. So that I can get up close and personal with that cable. And get a look at the root station.’

‘OK,’ Sally said dubiously. ‘Suppose, hypothetically, we agree we’re going to do this. How? We don’t have twenty miles of rope – do we, Frank?’

‘No. Anyhow we’d need a lot more, for doubling up, fail-safes.’

‘We don’t have winches, or jet packs—’

‘We fly down,’ Willis said. ‘We take one of the gliders, and fly down.’ He looked at them both. ‘You’re going to say no, aren’t you? Look. You can see how wide this pit is. A half-mile across – plenty of room for a spiral flight, down and back up.’

‘The air at the base is a hell of a lot thicker than the design optimum, Willis,’ Frank protested.

‘You know as well as I do that fifty per cent bar is still within the performance envelope. And besides, there’s a lot of heat seeping out of this hole in the ground. We can ride back up using the thermals; that will help.

‘Here’s the plan. Two of us will ride one glider down, leaving the other glider on the surface as backup, together with one pilot. We can offload stores before the flight. There are obvious fallback strategies, if anything goes wrong. Maybe we could even climb back up, out of this pit. The gravity is a baby.’

Frank said, ‘Why not send down a drone plane?’

‘Not equipped to take samples.’

‘But—’

‘End of discussion,’ Willis said. ‘We came here for that damn space elevator. We ain’t going home without a piece of it. Got that? OK. Let’s get down to specifics.’

They argued about how to split the crew. They agreed that one should stay on the surface, two descend. Which one, which two?

In fact the logic was clear. Willis was always going to go into the pit. Sally was the least good pilot, but as the youngest and fittest she had the best chance of climbing out of that hole in the ground if things got bad enough. Frank, meanwhile, the best pilot, was the obvious choice for the reserve on the surface.

Willis and Sally it would be, then.

Willis fretted through the day that Frank insisted they took in offloading Thor , the glider to be used for the descent, testing through its systems one more time, checking over their pressure suits and other gear, working out communications protocols and the like. And if Willis was restless, Frank was visibly unhappy, whether because the stunt was so obviously dangerous or because he was the guy left behind to mind the store, Sally wasn’t sure.

Come the evening they had a hot meal in one of the bubble tents, washed up, and took to their sleeping bags early. The plan was to rise at dawn and use the full day to descend, do whatever had to be done at the base of the pit, and climb back out again before the sun fell.

That night Sally slept no better and no worse than she had during the whole trip. Another legacy of her solitary, nomadic life: she had adapted to getting by on whatever sleep she could snatch, as and when she got the chance. She was always aware, though, oddly, of the thread to the sky just a couple of miles away, silent, ancient, with space at its tip and some kind of fallen culture at its feet. Her life had always been odd, even before Step Day. Just when she’d thought it couldn’t get any odder . . .

Thor lifted, propelled by the methane rockets, as obedient and responsive as ever. Willis was piloting.

Once they were into their glide Willis made one circle over the landing site. Sally looked down at the ground, at Woden gleaming bone white in the morning sun, and their bubble tents like blisters on the scuffed Martian dust. Frank Wood stood alone, staring up. He waved, and Willis waggled the wings in response.

Sally still had that faint alarm bell ringing in the back of her head. There was something about this situation that wasn’t right, that they hadn’t thought through or prepared for. Well, Frank Wood was more experienced than Sally in this kind of situation, less intelligent than Willis maybe but calmer, more capable in many ways. If something did blow up, she’d have to rely on Frank’s instincts to save the day.

Thor turned away from the landing site and towards the pit, and Sally turned her attention to the challenge facing her.

They were over the pit in only a couple of minutes. Willis, getting the feel of the craft, took Thor banking in tight circles over the opening, keeping one eye on the elevator cable. ‘I can see the cable easily,’ he said with some relief. ‘Also I rigged up a proximity sensor that will ping if we get too close. Short of flying straight at the damn thread, we should be OK.’

‘Don’t tempt fate, Dad.’

‘Now you sound like your maternal grandfather, Patrick. Remember him? The gloomy Irishman. OK, let’s take her down.’

He began a lazy spiral around the axial cable, cutting the speed, Sally guessed, as low as he dared without risking a stall. Soon they were descending towards the mouth of the pit, the low sunlight wheeling through the glider cabin – and then, with a smooth wash of rising shadow, they fell beneath the lip of the hole, with its artfully consolidated ridge. The sun caught only the uppermost stretch of the wall of crimson rock, and soon they were falling into the darkness.

Sally felt an odd sense of claustrophobia. But that was logical, for her, with the instincts of a natural stepper. Sally had grown up knowing in her bones that as a last resort, whatever difficulty she got into, she could always just step away, even without a Stepper box. Even on the Long Mars that was true, though she would generally just be swapping one lethal landscape for another. But you couldn’t step out of a pit, a hole dug into the ground, because there would be earth and bedrock in the worlds to either side stepwise. A pit, a basement, a cellar, even a mine, was therefore a simple defence against stepping aggressors, as had been figured out very early after Step Day, even by neighbourhood cops like Monica Jansson.