Bram followed her around as best he could, climbing in and out of the walker, helping with the measurements, and operating the little portable thumper that located cavities beneath the surface.
“Libraries,” Ame exulted. “I’m sure of it. And museum warehouses and storehouses and depots and vaults for frozen samples. And all the support and recreational facilities you’d need for the population of millions that it would have taken to run this outpost—hydroponic farms, maybe even zoos! This will be a treasure trove for the archaeologists, Bram-tsu! And there’ll be middens—we’ll find seeds and organic refuse and bones…”
He didn’t like leaving her alone while he went off on his own side forays, and at one point he coaxed her into the walker for an excursion to the rim’s edge.
“Don’t go out any farther,” he warned. “I don’t know how secure this thing is.”
They were standing on the great skeleton arm of a gantry that extended out over the abyss—part of some sort of transport system that traveled an unknown distance down the face. Bram could see the stanchions that once might have supported an elevator or funicular dwindling with distance till they disappeared.
Hundreds—possibly thousands—of miles down the sheer face began a glittering fairy forest of tiny filaments that swept in a great arc until they could no longer be distinguished against the knife edge that cut the black night ninety million miles below.
“The feed array for the antenna system,” Bram said. “There must be others, equally spaced around the disk, aimed at a reflector at the hub.”
By this time they had worked themselves through to the opposite edge of the disk, facing the intergalactic night. The antenna complex was lit from above by ruddy moonlight.
The buried city, limned by mounded avenues of detritus, stretched all the way across the diskworld from rim to rim. And Jao had been right: There was another set of cables climbing to the moon on this side, too.
“So this,” Ame said, “was the voice of the human race?”
“Yes.” Bram dug through the centuries for an old memory. “My teacher, Voth, once said that humankind had learned to tame a sun’s power to shout across the gulf between the galaxies, but he couldn’t imagine how.”
He mused at the phased array, wondering at the scale that would allow its nearer ranks to be seen at such a distance. The elements must be miles high to be even remotely distinguishable—cantilevered or guyed against the topsy-turvy gravity. But that would have presented no problem to a race with moonrope at its disposal. And the gravity would be mild for the next few million miles, anyway. It would be a different story at the hub, where gravity would be crushing. Perhaps there were phase shifters installed at a safe radius. He would send an expedition down the face to see—in a space vehicle. And the physics would have to be carefully worked out so that the explorers would not find themselves slammed against a wall that had become a floor.
Bram shuddered at the thought of the mighty energies that once had been dispensed by that distant forest. In operation, it would have been a microwave inferno that would have sizzled a man to a crisp in milliseconds. No wonder a healthy stretch of no-man’s-land had been left—and not just to get past the gravitational edge effects.
Bram inched farther out on the gantry for a better look. Jao was going to insist on a full description. Too energetic a toe push sent him doing a handstand, and he walked a few steps on his hands before his boots settled down, holding on for dear life and being careful not to let go with one hand before he had a firm grip with the other. The asterioid-strength gravity was deceptive, he knew. He still had all his mass, and it was a long way to fall. Already, though he was no more than fifty yards over the edge, he knew that the horizontal component of the diskworld’s complex gravity was tugging every atom of his body toward itself in a complicated vector. He would have had to crawl out another million miles or so to feel anything, of course, but it was there nevertheless. But if he were to fall past reach of a handhold, he would be accelerated inexorably—at the dreamlike rate of about one thirty-millionth of a foot per second to start—until, at an unknown fraction of the distance to the center, the reaching forces of the disk would slam him into the tilted wall-scape at a velocity sufficient to abrade him into a long, wet smear.
It didn’t help a whit to realize that he’d have been long dead of suffocation, thirst, or boredom before that happened.
Bram stopped his balloonlike four-limbed outward prowl and wrapped himself securely around a thick strut with an arm and a leg while he surveyed the cliff face from his improved vantage point.
There was movement beside him, and then Ame was pressed up next to him, peering past his shoulder into the abyss.
“I thought I told you to stay put,” Bram said.
“Don’t be silly, Bram-tsu. I’m perfectly able to take care of myself. What could possibly happen?” She leaned out alarmingly. “Do you think we have enough time to climb down there for a look at some of those caves?”
“No!” he said, hearing himself sputter. In a more reasonable tone of voice, he said, “We’ll come back later with ropes and proper climbing equipment and a team of trained outside workers. Maybe we’ll round up a few tame climbers from Yggdrasil’s vascular system and ride them. And the climbers will wear safety lines, too!”
“It was just an idea,” she said mildly.
She unclipped her torch from her belt and played it over the vertical surface below. Seen up close, Jao’s “smooth face” was pocked with great pits and hollows. Looking at this cross section of a world, Bram could see where the crust began, a few miles below, like frosting on a slice of cake. The artificial material beneath was thinly covered with dust, and all sorts of domes, bulges, and the craters of burst bubbles poked above the rubbish of the sundered planet that had been used as a starter.
Closer at hand, vacuum welding over the eons had cemented a rocky cliffside in place. But here, too, even the languorous stresses that the diskworld was heir to had from time to time torn great chunks of material loose and left a pattern of cracks and cavities.
Ame’s beam found one of the holes. “I wonder bow deep—” she began, and stopped.
A pair of animal eyes shone in the beam of light for a startled second, then whisked out of sight.
“Oh!” Ame squeaked. She dropped the torch. It seemed to hang in space beside her; the light beam revolving in lazy circles. Ame recovered before the torch had drifted down more than an inch or two, caught it by the wrong end, and got it pointed at the cave again.
“Did you see it, too?” she whispered.
“Yes,” Bram said.
There was life in this place. And it was shy.
They stayed clinging to their dizzy perch until Lydis’s radioed warnings about their reserve air supply became too impatient to ignore. But the beady, luminous eyes never reappeared.
“It’s hunkered at the back of the cave, waiting for us to go away,” Ame said.
“Or there’s a way out through the rear,” Bram suggested. “There may be a whole system of burrows.”
She had tried the light in every opening it would reach. Far below, at the limit of the beam, they thought they saw a pair of pinpoints of reflected light for the briefest flash, but it was impossible to be sure. Finally, when Lydis began making threats, they gave up and hauled themselves back along the gigantic crane arm to the security of the rim.
They had left the walker parked a short distance away in a square at the intersection of two avenues of raised gravel. As they approached it, there was an explosion of movement around it, and dozens of small furry forms streaked away into hiding.