The land became steadily more treacherous. They worked their way past moraines, heaps of rubble left by the retreating ice. The rubble was of all sizes, from gritty sand to boulders larger than a mammoth. The moraines were cut through by meltwater rivers that varied unpredictably from trickles to mighty, surging flows, and the rubble heaps were unstable, liable to slump and collapse at any time.
As they pressed farther, a great wind rose, katabatic, pouring directly off the ice sheet and into their faces. It was a hard time. There was little to eat or drink and every step required a major effort, but they persisted. And Longtusk was careful to encourage his charges to gather as much strength as possible, for he knew that only harder days, if anything, lay ahead of them all.
At last they encountered the ice itself.
They reached the nose of a glacier. It was a wall of ice, cracked and dirty and forbidding. Blocks of broken ice, calved off the glacier like miniature icebergs, lay unmelting on rock that was rust-red, brown and black. Tornado-like columns of ice crystals spun across the barren rock in the wind, whipping up small lumps of sandstone that flew through the air, peppering the mammoths’ hides.
This was the terminus of a huge river of ice that poured, invisibly slowly, from the vast cap that still lay to the east.
The mammoths paused to gather breath, hunted without success for food, and then began the ascent.
Longtusk picked his way onto the great ice river, stepping cautiously over a shattered, chaotic plain of deeply crevassed blue ice. The glacier was a river of raw white, its glare hurting his eyes, shining under the sky’s clean blue. He could see the glacier’s source, high above him, at the lip of the ice sheet itself. Where he could he chose paths free of crevasses and broken surfaces, but he could usually find easier ground near the glacier’s edges, hugging the orange rock of the valley down which the glacier poured.
It was difficult going. Sometimes loose snow was whipped up by the wind and driven over the surface, obscuring everything around him up to shoulder height. But, above the snow, the sky was a deep blue.
At last the ice beneath his feet leveled out, and he realized he had reached a plateau.
It was the lip of the ice sheet.
He was standing on a sea of gleaming ice, which shone in every direction he looked, white, blue and green. The ice receded to infinity, flat white under blue sky — but perhaps his poor eyes could make out a shallow dome shape as the ice rose, sweeping away from him toward the east.
It was utterly silent and still, without life of any kind, the only sound the snort of his trunk, the only motion the fog of his breath.
He turned, ponderously, and looked back the way he had come.
This edge of the ice was marked by mountains, heavily eroded and all but buried, and he could see how the glacier spilled between the peaks toward the lower ground. Though locked into the slow passage of time, the glacier was very obviously a dynamic river of ice. Huge parallel bands flowed neatly down the valley’s contours. The bands marked the merging of tributaries, smaller ice rivers that flowed into the main stream, each of them keeping their characteristic color given them by the rock particles they had ground up and carried. Where the glacier reached the lower land it spread out, cracking, making the jumbled surface of crevasses he had struggled to cross.
Everything flowed down from here, down to the west and the lower ground, as if he had climbed to the roof of the world. He was cold, exhausted, hungry, and thirsty; and he was still not confident of surviving this immense venture. But, standing here, looking down on the great frozen majesty of the icecap and its rivers, he felt exhilarated, privileged.
He turned to face the east, ready to go on.
He stepped forward experimentally. The ice was unforgivingly cold, seeming to suck his body heat out through the thick callused pads on his feet. It was harder than any rock he had encountered — but it was not smooth. It was choppy, rippled, like the surface of a lake under the wind. But the ripples were frozen in place, and the footing was, surprisingly, quite secure, thanks to those scalloped ripples.
There is nothing to eat here, he thought dryly. There is no shelter, and if I stay too long I will surely freeze to death. But at least I won’t slip and fall.
He began to walk, and the others followed him. He could feel the ice’s flow in his belly, a deep disturbing subsonic murmur as it poured with immense slowness toward the lip.
The cap was one of a string of great domes of ice that littered the northern hemisphere of the planet. As its center the icecap was kilometers thick, as humans would have measured it, and the bedrock beneath — ground free of life and locked in darkness — was crushed downward through many meters.
The dome was fed by fresh falls of snow on its upper surface. The new snow crushed the softer layers beneath, forcing out the air and turning them into hard blue ice. The collapsing center forced ice at the rim to flow down to lower altitudes, in the form of glaciers that gouged their way through river valleys and, where the ice met open water, they floated off to form immense shelves.
The ice was like a huge, subsiding mass of soft white dung, flattening and flowing, continually replenished from above.
The glaciers’ flow was enormously slow — perhaps advancing by a mere mammoth footstep every year. But the icecap was nevertheless shrinking. Less snow was falling on the icecap than it was losing to its glaciers and ice shelves. The cap was inevitably disintegrating, though it would take an immense time to disappear.
At first, under blue skies, it was exhilarating to be here. But even from the start the icecap was not without its dangers.
Once, Longtusk walked over a place were the ice had frozen into a thin crust that seemed to lie on deeper snow. When he took a step the surface settled abruptly. He fell — not far, just enough to startle him. And then the crust around him continued to collapse, the cracks spreading for many paces as the surface settled. The crunching, crackling noise of the ice seemed to circle him. It was eerie, like the actions of a living thing in this place where nothing could live, and he was glad to pass onto firmer ice.
…Even the light was strange.
Sometimes, when the sun was low in the sky, there were rings and arcs surrounding it, glimmering in the sky, and even false images of the sun to either side of it, or nestling on the horizon. It was like the blurred multiple images Longtusk would sometimes see when his eyes were wind-battered and filled with tears, so that he had to peer at the world through a lens of water.
When the nights were clear they were blue, as the moonlight was reflected from the ice. Even when there was no Moon, and only stars shone, the nights would still be bright and blue, so powerfully did the ice capture and reflect even the stars’ trickle of light.
On the third day the sky clouded over, and a white mist descended.
The light grew bright but soft, the details of the sky and even the ice under his feet hazing. Soon the horizon was invisible and the sky was joined seamlessly to the ground, as if he was walking inside some huge hollowed-out gull’s egg. The light was very bright, enough to hurt his eyes, and gray-white floaters drifted like birds across his vision. There was no shadow, no relief, no texture. He could make out the line of mammoths behind him, robust stocky forms laboring across the ice, their heads wreathed in steam. They were the only objects he could see in the whole world, as if they were all floating in clouds, disengaged from the Earth.