Three days of similar researches demonstrated that the city was invulnerable to intrusion from above or below.
"There's only one way in," said Hosteen, "and that's on foot, through the main gate."
"If the people in the city really wanted to be safe," Rawlins asked, "why did they leave even a gate open?"
"Maybe they wanted to go in and out themselves, Ned," said Boardman quietly. "Or maybe they wanted to give invaders a sporting chance. Hosteen, shall we send some probes inside?"
The morning was gray. Clouds the color of wood smoke stained the sky; it looked almost as if rain were on the way. A harsh wind knifed the soil from the plain and sent it slicing into their faces. Behind the veil of clouds lay the sun, a flat orange disk that seemed to have been pasted into the sky. It seemed only slightly larger than Sol as seen from Earth, though it was less than half as distant. Lemnos' sun was a gloomy M dwarf, cool and weary, an old star circled by a dozen old planets. Lemnos, the innermost, was the only one that had ever sustained life; the others were frigid and dead, beyond the range of the sun's feeble rays, frozen from core to atmosphere. It was a sleepy system with so little angular momentum that even the innermost planet dawdled along in a thirty-month orbit; the three zippy moons of Lemnos, darting on crisscrossing tracks a few thousand kilometers overhead, were flagrantly out of keeping with the prevailing mood of these worlds.
Ned Rawlins felt a chill at his heart as he stood beside the data terminal a thousand meters from the outer embankment of the maze, watching his shipmates marshalling their probes and instruments. Not even dead pockmarked Mars had depressed him like this, for Mars was a world that had never lived at all, while here life had been and had moved onward. This world was a house of the dead. In Thebes, once, he had entered the tomb of Pharaoh's vizier, five thousand years gone, and while the others in his group had eyed the gay murals with their glowing scenes of white-garbed figures punting on the Nile, he had looked toward the cool stone floor where a dead beetle lay, clawed feet upraised on a tiny mound of dust. For him Egypt would always be that stiffened beetle in the dust; for him Lemnos was likely to be autumn winds and scoured plains and a silent city. He wondered how anyone as gifted, as full of life and energy and human warmth as Dick Muller, could ever have been willing to maroon himself inside that dismal maze.
Then he remembered what had happened to Muller on Beta Hydri IV, and conceded that even a man like Muller might very well have good reasons for coming to rest on a world like this, in a city like this. Lemnos offered the perfect escape: an Earthlike world, uninhabited, where he was almost guaranteed freedom from human company. And we're here to flush him out and drag him away. Rawlins scowled. Dirty dirty dirty, he thought. The old thing about the ends and the means. Across the way Rawlins could see the blocky figure of Charles Boardman standing in front of the big data terminal, waving his arms this way and that to direct the men fanning out near the walls of the city. He began to understand that he had let Boardman dragoon him into a nasty adventure. The glib old devil hadn't gone into details, back on Earth, about the exact methods by which they were going to win Muller's cooperation. Boardman had made it sound like some kind of shining crusade. Instead it was going to be a dirty trick. Boardman never went into the details of anything before he had to, as Rawlins was beginning to see. Rule one: hoard your resources of strategy. Never tip your hand. And so here I am, part of the conspiracy.
Hosteen and Boardman had deployed a dozen drones at the various entrances to the inner part of the maze. It was already clear that the only safe way into the city was through the northeastern gate; but they had drones to spare, and they wanted all the data they could gather. The terminal Rawlins was watching flashed a partial diagram of the maze on the screen—the section immediately in front of him—and gave him a good long time to study its loops and coils, its zigzags and twists. It was his special responsibility to follow the progress of the drone through this sector. Each of the other drones was being monitored both by computer and by human observer, while Boardman and Hosteen were at the master terminal watching the progress of the entire operation all at once.
"Send them in," Boardman said.
Hosteen gave the command, and the drones rolled forward through the city's gates. Looking now through the eyes of the squat mobile probe, Rawlins got his first view of what lay in Zone H of the maze. He saw a scalloped wall of what looked like puckered blue porcelain undulating away to the left, and a barrier of metallic threads dangling from a thick stone slab to the other side. The drone skirted the threads, which tinkled and quivered in delicate response to the disturbance of the thin air; it moved to the base of the porcelain wall, and followed it at an inward-sloping angle for perhaps twenty meters. There the wall curved abruptly back on itself, forming a sort of chamber open at the top. The last time anyone had entered the maze this way—on the fourth expedition—two men had passed that open chamber; one had remained outside and was destroyed, the other had gone inside and was spared. The drone entered the chamber. A moment later a beam of pure red light lanced from the center of a mosaic decoration on the wall and swept over the area immediately outside the chamber.
Boardman's voice came to Rawlins through the speaker taped to his ear. "We lost four of the probes the moment they went through their gates. That's exactly as expected. How's yours doing?"
"Following the plan," said Rawlins. "So far, it's okay."
"You ought to lose it within six minutes of entry. What's your elapsed time now?"
"Two minutes fifteen."
The drone was out of the chamber now and shuttling quickly through the place where the light-beam had flashed. Rawlins keyed in olfactory and got the smell of scorched air, lots of ozone. The path divided ahead. To one side was a single-span bridge of stone, arching over what looked like a pit of flame; to the other was a jumbled pile of cyclopean blocks resting precariously edge to edge. The bridge seemed far more inviting, but the drone immediately turned away from it and began to pick its way over the jumbled blocks. Rawlins asked it why, and it relayed the information that the "bridge" wasn't there at all; it was a projection beamed from scanners mounted beneath the facing piers. Requesting a simulation of an approach anyway, Rawlins got a picture of the probe walking out onto the pier and stepping unsuspectingly through the solid-looking bridge to lose its balance; and as the simulated probe struggled to regain its equilibrium, the pier tipped forward and shucked it into the fiery pit. Cute, Rawlins thought, and shuddered.
Meanwhile the real probe had clambered over the blocks and was coming down the other side, unharmed. Three minutes and eight seconds had gone by. A stretch of straight road here turned out to be as safe as it looked. It was flanked on both sides by windowless towers a hundred meters high, made of some iridescent mineral, sleek and oily-surfaced, that flashed shimmering moiré patterns as the drone hurried along. At the beginning of the fourth minute the probe skirted bright grillwork like interlocking teeth, and sidestepped an umbrella-shaped piledriver that descended with crushing force. Eighty seconds later it stepped around a tilt-block that opened into a yawning abyss, deftly eluded a quintet of tetrahedal blades that sheared upward out of the pavement, and emerged onto a sliding walkway that carried it quickly forward for exactly forty seconds more.
All this had been traversed long ago by a Terran explorer named Cartissant, since deceased. He had dictated a detailed record of his experiences within the maze. He had lasted five minutes and thirty seconds, and his mistake had come in not getting off the walkway by the forty-first second. Those who had been monitoring him outside, back then, could not say what had happened to him after that.
As his drone left the walkway, Rawlins asked for another simulation and saw a quick dramatization of the computer's best guess: the walkway opened to engulf its passenger at that point. The probe, meanwhile, was going swiftly toward what looked like the exit from this outermost zone of the maze. Beyond lay a well-lit, cheerful-looking plaza ringed with drifting blobs of a pearly glowing sub
stance.
Rawlins said, "I'm into the seventh minute, and we're still going, Charles. There seems to be a door into Zone G just ahead. Maybe you ought to cut in and monitor my screen."
"If you last two more minutes, I will," Boardman said.
The probe paused just outside the inner gate. Warily it switched on its gravitron and accumulated a ball of energy with a mass equivalent to its own. It thrust the energy ball through the doorway. Nothing happened. The probe, satisfied, trundled toward the door itself. As it passed through, the sides of the door abruptly crashed together like the jaws of a mighty press, destroying the probe. Rawlins' screen went dark. Quickly he cut in one of the overhead probes; it beamed him a shot of his probe lying on the far side of the door, flattened into a two-dimensional mock-up of itself. A human being caught in that same trap would have been crushed to powder, Rawlins realized.
"My probe's been knocked out," he reported to Boardman. "Six minutes and forty seconds."
"As expected," came the reply. "We've got only two probes left. Switch over and watch."
The master diagram appeared on Rawlins' screen: a simplified and stylized light-pen picture of the entire maze as viewed from above. A small X had been placed wherever a probe had been destroyed. Rawlins found, after some searching, the path his own drone had taken, with the X marked between the zone boundaries at the place of the clashing door. It seemed to him that the drone had penetrated farther than most of the others, but he had to smile at the childish pride the discovery brought him. Anyhow, two of the probes were still moving inward. One was actually inside the second zone of the maze, and the other was cruising through a passageway that gave access to that inner ring.
The diagram vanished and Rawlins saw the maze as it looked through the pickup of one of the drones. Almost daintily, the man-high pillar of metal made its way through the baroque intricacies of the maze, past a golden pillar that beamed a twanging melody in a strange key, past a pool of light, past a web of glittering metal spokes, past spiky heaps of bleached bones. Rawlins had only glancing views of the bones as the drone moved on, but he was sure that few were human relics. This place was a galactic graveyard for the bold.
Excitement built in him as the probe went on and on. He was so thoroughly wedded to it now that it was as if he were inside the maze, avoiding one deathtrap after another, and he felt a sense of triumph as minutes mounted. Fourteen had elapsed now. This second level of the maze was not so cluttered as the first; there were spacious avenues here, handsome colonnades, long radiating passages leading from the main path. He relaxed; he felt pride in the drone's agility and in the keenness of its sensory devices. The shock was immense and stinging when a paving-block upended itself unexpectedly and dumped the probe down a long chute to a place where the gears of a giant mill turned eagerly.
They had not expected that probe to get so far, anyway. The probe the others were watching was the one that had come in via the main gate—the safe gate. The slim fund of information accumulated at the price of many lives had guided that probe past all its perils, and now it was well within Zone G, and almost to the edge of F. Thus far, everything had gone as expected; the drone's experiences had matched those of them who had tackled this route on earlier expeditions. It followed their way exactly, turning here, dodging there, and it was eighteen minutes into the maze without incident.
"All right," Boardman said. "This is where Mortenson died, isn't it?"
"Yes," Hosteen answered. "The last thing he said was that he was standing by that little pyramid, and then he was cut off."
"This is where we start gaining new information, then. All we've learned so far is that our records are accurate. This is the way in. But from here on—"
The probe, lacking a guidance pattern, now moved much more slowly, hesitating at every step to extend its network of data-gathering devices in all directions. It looked for hidden doors, for concealed openings in the pavement, for projectors, lasers, mass-detectors, power sources. It fed back to the central data banks all that it learned, thus adding to the store of information with each centimeter conquered.
It conquered, altogether, twenty-three meters. As the probe passed the small pyramid it scanned the broken body of the explorer Mortenson, lost at this point 72 years earlier. It relayed the news that Mortenson had been seized by a pressure-sensitive mangle activated by an unwary footstep too close to the pyramid. Beyond, it avoided two minor traps before failing to safeguard itself from a distortion, screen that baffled its sensors and left it vulnerable to the descent of a pulverizing piston.
"The next one through will have to cut off all its inputs until it's past that point," Hosteen muttered. "Running through blindfolded —well, we'll manage."
"Maybe a man would do better than a machine there," said Boardman. "We don't know if that screen would muddle a man the way it did a batch of sensors."
"We're not yet ready to run a man in there," Hosteen pointed out.
Boardman agreed—none too graciously, Rawlins thought, listening to the interchange. The screen brightened again; a new drone probe was coming through. Hosteen had ordered a second wave of the machines to pick through the labyrinth, following what was now known to be the one safe access route, and several of them were at the eighteen-minute point where the deadly pyramid was located. Hosteen sent one ahead, and posted the others to keep watch. The lead probe came within range of the distortion screen and cut out its sensors; it heaved tipsily for a moment, lacking any way to get its bearings, but in a moment it was stable. It was deprived now of contact with its surroundings, and so it paid no heed to the siren song of the distortion screen, which had misled its predecessor into coming within range of the pulverizing piston. The phalanx of drones watching the scene was all outside the reach of the distorter's mischief, and fed a clear, true picture to the computer, which matched it with the fatal path of the last probe and plotted a route that skirted the dangerous piston. Moments later the blind probe began to move, guided now by inner impulses. Lacking all environmental feedback it was entirely a captive of the computer, which nudged it along in a series of tiny prods until it was safely around the hazard. On the far side, the sensors were switched on again. To check the procedure, Hosteen sent a second drone through, likewise blinded and moving entirely on internal guidance. It made it. Then he tried a third probe with its sensors on and under the influence of the distortion screen. The computer attempted to direct it along the safe path, but the probe, bedeviled by the faulty information coming through the distorter, tugged itself furiously to the side and was smashed.
"All right," Hosteen said. "If we can get a machine past it, we can get a man past it. He closes his eyes, and the computer calculates his motions step by step. We'll manage."
The lead probe began to move again. It got seventeen meters past the place of the distorter before it was nailed by a silvery grillwork that abruptly thrust up a pair of electrodes and cut loose with a bath of flame. Rawlins watched bleakly as the next probe avoided that obstacle and shortly fell victim to another. Plenty of probes waited patiently for their turn to press forward.
And soon men will be going in there too, Rawlins thought. We'll be going in there.
He shut off his data terminal and walked across to Boardman.
"How does it look so far?" he asked.
"Rough, but not impossible," Boardman said. "It can't be this tough all the way in."
"And if it is?"
"We won't run out of probes. We'll chart the whole maze until we know where all the danger points are, and then we'll start trying it ourselves."
Rawlins said, "Are you going to go in there, Charles?"
"Of course. So are you."
"With what odds on coming out?"
"Good ones," said Boardman. "Otherwise I doubt that I'd tackle it. Oh, it's a dangerous trip, Ned, but don't overestimate it. We've just begun to test that maze. We'll know it well enough in a few days more."
Rawlins considered that a moment. "Muller didn't have a
ny probes," he said finally. "How did he survive that stuff?"
"I'm not sure," Boardman murmured. "I suppose he's just a naturally lucky man."
THREE
Within the maze Muller watched the proceedings on his dim screens. They were sending some sort of robots in, he saw. The robots were getting chewed up quite badly, but each successive wave of them seemed to reach deeper into the labyrinth. Trial and error had led the intruders to the correct route through Zone H and well onward into G. Muller was prepared to defend himself if the robots reached the inner zones. Meanwhile he remained calm at the center of it all, going about his daily pursuits.
In the mornings he spent a good deal of the time thinking over his past. There had been other worlds in other years, springtimes, warmer seasons than this; soft eyes looking into his eyes, hands against his hands, smiles, laughter, shining floors, and elegant figures moving through arched doorways. He had married twice. Both times the arrangements had been terminated peacefully after a decent span of years. He had traveled widely. He had dealt with ministers and kings. In his nostrils was the scent of a hundred planets strung across the sky. We make only a small blaze, and then we go out; but in his springtime and his summer he had burned brightly enough, and he did not feel he had earned this sullen, joyless autumn.
The city took care of him, after its fashion. He had a place to dwell—thousands of places; he moved from time to time for the sake of changing the view. All the houses were empty boxes. He had made a bed for himself of animal hides stuffed with scraped fur; he had fashioned a chair from sinews and skin; he needed little else. The city gave him water. Wild animals roamed here in such quantity that he would never lack for food so long as he was strong enough to hunt. From Earth he had brought with him certain basic items. He had three cubes of books and one of music; they made a stack less than a meter high and could nourish his soul for all the years that remained to him. He had some woman cubes. He had a small recorder into which he sometimes dictated memoirs. He had a sketchpad. He had weapons and a mass detector. He had a diagnostat with a regenerating medical supply. It was enough.