Greg Egan
PHORESIS
PART ONE
1
Freya walked slowly across the ice, using her rake to scrape aside the thin cover of dirt and crystalline powder, peering down into the translucent slab below for any sign of a slender rootlet struggling to force its way out into the air.
Something dark and linear caught her eye, about a hand’s breadth deep. She stopped walking and squatted down for a closer look, then she took her pick and swung it into the ice. Once the surface shattered it was impossible to see anything beneath it, but after a dozen blows she stopped and cleared the debris out of the hole she’d made. She’d exposed the inclusion, but it wasn’t a root: it was just a streak of trapped gravel.
The sun was behind a bank of reddish clouds that covered most of the western sky and left the ice field in a state of ambiguous gloom, so she glanced up at Tvíburi, hoping to find that the time had sped by while she worked. But the twin world was still just a crescent: the afternoon shift was barely half over.
Freya was tired and hungry. She took a deep breath and held it in to make the most of it; by the time she exhaled she felt a little steadier. The air was thin from the sun’s recent tantrums, but thousands of villages besides her own would be performing the same time-tested remedy. The Yggdrasils thrived on the temperature difference between the buried ocean and the cool of the surface, but sometimes their roots didn’t make it all the way through the ice. Chipping away the final barrier let them complete their journey—and once they were exposed to the open air, they were free to dispense all the volatile treasures they’d pumped up from below.
Off to her right, her nearest neighbor was intent on her own patch, and too far away to converse with unless they shouted. Freya stopped procrastinating and recommitted herself to the task. The sooner they’d reached their quota, the sooner they could all go home.
The communal tent was noisy, and the long table was more crowded with diners than food, but Freya was glad to be out of the cold, walking barefoot on the tent’s tattered rugs. She eyed the remaining provisions and estimated a fair share, then she gathered the food up quickly before someone assumed she’d lost her appetite.
It was only as she sat down to eat that she realized she’d arrived in the middle of an argument. “And what about the soil?” Gro demanded. “This is just a stopgap! It might help us breathe, but it’s not going to give us so much as a handful of new soil.”
“You want to dig a whole new geyser while we’re out here?” Hanna teased her. “Cleave through a few thousand strides of ice and…” She gestured with her hands, miming an eruption. “What could be simpler?”
“So if we don’t know how to fix the problem, no one should talk about it?” Gro retorted. “In my mother’s day, the yields were at least a third more than they are now!”
“So tighten your stomach,” Bridget advised.
“And keep your brothers in check,” Hanna joked.
Gro’s demeanor was becoming increasingly sour. “Will you laugh when your children are born too small and sickly to survive?”
“You didn’t tell us you were pregnant,” Erna interjected solemnly, tentatively offering Gro some of her own food.
“I’m not!” Gro gripped the table in frustration. “So does anyone else believe that there’s a problem? Or am I just imagining it?”
Freya said, “The yields are going down, everyone’s seeing it.”
“At last! Thank you!” Gro stood up, as if to walk over and embrace her in gratitude, but then she changed her mind and sat down again.
“But I don’t know what we can do, except hope for a fresh geyser,” Freya added. She had never heard of any kind of intervention that could achieve such a goal.
Gro said, “How about acknowledging that this isn’t going to fix itself, and turning our minds to finding a solution?”
There was a moment of silence from the other members of the group, and then Hanna conceded, “There must have been a time before anyone thought about exposing the roots. When they all just sat around, too tired to move, waiting for the air to replenish itself.”
“Exactly,” Gro replied. “And if they’d kept on that way, we might not even be here now.”
“But a geyser?” Bridget protested.
“If it were easy,” Gro said, “it would have happened long ago. Keep it in your minds, that’s all I’m asking. Search your thoughts while you search the ground. It might even help you pass the time.”
The next morning, Freya took Gro’s advice, staring into the ice as diligently as ever as she trudged across the unbroken plain, but letting the impossible problem sit like a nagging onlooker in the back of her skull.
Geysers came and went, with no apparent pattern to their arrivaclass="underline" bursting out of the ice and then flowing twice a day, lasting anything from a year to a century. As fickle as the sun’s own eruptions, they provided an erratic counterbalance to those air-ablating blasts. But while Freya had no idea what caused the solar flares, every child was taught the origin of the geysers.
As Tvíbura and Tvíburi turned together, their mutual orbit swung them around in a single day, compared to the fifteen days it took them to circle the sun. So Tvíbura’s choice to fix her gaze upon her twin precluded the same relationship with her light-giving mother—and just as well, on every count Freya could think of. People joked about the lonely cousins in the realms where Tvíburi was hidden from sight, but while the gifts of nocturnal light and an immovable beacon to navigate by were great boons, if the world had instead been divided into the eternally sunlit and the eternally dark, neither half would have been grateful.
But the other benefits of Tvíbura’s rotational allegiance were just as crucial. Only a single point at the center of the world could fall freely, surrendering completely to its mother’s and sister’s pull; the rest of the rock, ice and ocean that was dragged along with it was forced to compromise, struggling to hold together despite gravity’s predilection for tugging harder on whatever happened to be nearest. And unlike the force wielded by Tvíburi, to which the world could accommodate once and for all, the sun’s stretching and squeezing cycled relentlessly as it rose and set. The rock at the core grew hot from this endless kneading—which kept the ocean around it from freezing solid all the way down. The ocean, trapped between rock and ice, was forced to push hard against its confines, and the same gravitational edicts acting on the ice itself left it groaning and splintering. When the flaws in the ice lined up, the pressure of the water was enough to drive the ocean’s riches all the way to the surface and beyond—restoring the air, and raining fresh, fertile soil down upon the land.
Freya paused to examine a dark smudge in the ice. But it was too diffuse to be a rootlet; it was just dirt, trapped beneath the now-compacted crystalline snow from some long-extinct geyser.
It took the strength of the sun itself and the rush of two worlds through the void to crack the ice and squeeze the ocean into the sky. The pause they were suffering was not from any lack of the usual forces; it could only be that the fractures required for a geyser were currently misaligned, present here and there at different depths but failing to meet up. If water had been finding a path to the surface lately, word of the event might not have reached the village—but the thicker, sweeter air it brought would have made itself known long ago.