“What are they after?” Morrison asked.

  “God knows.” O'Neill leafed intently through the papers on his clipboard. “We'll have to analyze all our back-order slips.”

  Below them, the autofac exploring crew disappeared behind. The helicopter passed over a deserted stretch of sand and slag on which nothing moved. A grove of scrub-brush appeared and then, far to the right, a series of tiny moving dots.

  A procession of automatic ore carts was racing over the bleak slag, a string of rapidly moving metal trucks that followed one another nose to tail. O'Neill turned the helicopter toward them and a few minutes later it hovered above the mine itself.

  Masses of squat mining equipment had made their way to the operations. Shafts had been sunk; empty carts waited in patient rows. A steady stream of loaded carts hurled toward the horizon, dribbling ore after them. Activity and the noise of machines hung over the area, an abrupt center of industry in the bleak wastes of slag.

  “Here comes that exploring crew,” Morrison observed, peering back the way they had come. “You think maybe they'll tangle?” He grinned. “No, I guess it's too much to hope for.”

  “It is this time,” O'Neill answered. “They're looking for different substances, probably. And they're normally conditioned to ignore each other.”

  The first of the exploring bugs reached the line of ore carts. It veered slightly and continued its search; the carts traveled in their inexorable line as if nothing had happened.

  Disappointed, Morrison turned away from the window and swore. “No use. It's like each doesn't exist for the other.”

  Gradually the exploring crew moved away from the line of carts, past the mining operations and over a ridge beyond. There was no special hurry; they departed without having reacted to the ore-gathering syndrome.

  “Maybe they're from the same factory,” Morrison said hopefully.

  O'Neill pointed to the antennas visible on the major mining equipment. “Their vanes are turned at a different vector, so these represent two factories. It's going to be hard; we'll have to get it exactly right or there won't be any reaction.” He clicked on the radio and got hold of the monitor at the settlement. “Any results on the consolidated back-order sheets?”

  The operator put him through to the settlement governing offices.

  “They're starting to come in,” Perine told him. “As soon as we get sufficient samplings, we'll try to determine which raw materials which factories lack. It's going to be risky, trying to extrapolate from complex products. There may be a number of basic elements common to the various sublots.”

  “What happens when we've identified the missing element?” Morrison asked O'Neill. “What happens when we've got two tangent factories short on the same material?”

  “Then,” O'Neill said grimly, “we start collecting the material ourselves—even if we have to melt down every object in the settlements.”

  III

  In the moth-ridden darkness of night, a dim wind stirred, chill and faint. Dense underbrush rattled metallically. Here and there a nocturnal rodent prowled, its senses hyper-alert, peering, planning, seeking food.

  The area was wild. No human settlements existed for miles; the entire region had been seared flat, cauterized by repeated H-bomb blasts. Somewhere in the murky darkness, a sluggish trickle of water made its way among slag and weeds, dripping thickly into what had once been an elaborate labyrinth of sewer mains. The pipes lay cracked and broken, jutting up into the night darkness, overgrown with creeping vegetation. The wind raised clouds of black ash that swirled and danced among the weeds. Once an enormous mutant wren stirred sleepily, pulled its crude protective night coat of rags around it, and dozed off.

  For a time, there was no movement. A streak of stars showed in the sky overhead, glowing starkly, remotely. Earl Perine shivered, peered up, and huddled closer to the pulsing heat-element placed on the ground between the three men.

  “Well?” Morrison challenged, teeth chattering.

  O'Neill didn't answer. He finished his cigarette, crushed it against a mound of decaying slag, and, getting out his lighter, lit another. The mass of tungsten—the bait—lay a hundred yards directly ahead of them.

  During the last few days, both the Detroit and Pittsburgh factories had run short of tungsten. And in at least one sector, their apparatus overlapped. This sluggish heap represented precision cutting tools, parts ripped from electrical switches, high-quality surgical equipment, sections of permanent magnets, measuring devices—tungsten from every possible source, gathered feverishly from all the settlements.

  Dark mist lay spread over the tungsten mound. Occasionally, a night moth fluttered down, attracted by the glow of reflected starlight. The moth hung momentarily, beat its elongated wings futilely against the interwoven tangle of metal, and then drifted off, into the shadows of the thick-packed vines that rose up from the stumps of sewer pipes.

  “Not a very damn pretty spot,” Perine said wryly.

  “Don't kid yourself,” O'Neill retorted. “This is the prettiest spot on Earth. This is the spot that marks the grave of the autofac network. People are going to come around here looking for it someday. There's going to be a plaque here a mile high.”

  “You're trying to keep your morale up,” Morrison snorted. “You don't believe they're going to slaughter themselves over a heap of surgical tools and lightbulb filaments. They've probably got a machine down in the bottom level that sucks tungsten out of rock.”

  “Maybe,” O'Neill said, slapping at a mosquito. The insect dodged cannily and then buzzed over to annoy Perine. Perine swung viciously at it and squatted sullenly down against the damp vegetation.

  And there was what they had come to see.

  O'Neill realized with a start that he had been looking at it for several minutes without recognizing it. The search-bug lay absolutely still. It rested at the crest of a small rise of slag, its anterior end slightly raised, receptors fully extended. It might have been an abandoned hulk; there was no activity of any kind, no sign of life or consciousness. The search-bug fitted perfectly into the wasted, fire-drenched landscape. A vague tub of metal sheets and gears and flat treads, it rested and waited. And watched.

  It was examining the heap of tungsten. The bait had drawn its first bite.

  “Fish,” Perine said thickly.“The line moved. I think the sinker dropped.”

  “What the hell are you mumbling about?” Morrison grunted. And then he, too, saw the search-bug. “Jesus,” he whispered. He half rose to his feet, massive body arched forward.“Well, there's one of them. Now all we need is a unit from the other factory. Which do you suppose it is?”

  O'Neill located the communication vane and traced its angle. “Pittsburgh, so pray for Detroit … pray like mad.”

  Satisfied, the search-bug detached itself and rolled forward. Cautiously approaching the mound, it began a series of intricate maneuvers, rolling first one way and then another. The three watching men were mystified— until they glimpsed the first probing stalks of other search-bugs.

  “Communication,” O'Neill said softly. “Like bees.”

  Now five Pittsburgh search-bugs were approaching the mound of tungsten products. Receptors waving excitedly, they increased their pace, scurrying in a sudden burst of discovery up the side of the mound to the top. A bug burrowed and rapidly disappeared. The whole mound shuddered; the bug was down inside, exploring the extent of the find.

  Ten minutes later, the first Pittsburgh ore carts appeared and began industriously hurrying off with their haul.

  “Damn it!” O'Neill said, agonized. “They'll have it all before Detroit shows up.”

  “Can't we do anything to slow them down?” Perine demanded helplessly. Leaping to his feet, he grabbed up a rock and heaved it at the nearest cart. The rock bounced off and the cart continued its work, unperturbed.

  O'Neill got to his feet and prowled around, body rigid with impotent fury. Where were they? The autofacs were equal in all respects and the spot wa
s the exact same linear distance from each center. Theoretically, the parties should have arrived simultaneously. Yet there was no sign of Detroit— and the final pieces of tungsten were being loaded before his eyes.

  But then something streaked past him.

  He didn't recognize it, for the object moved too quickly. It shot like a bullet among the tangled vines, raced up the side of the hill-crest, poised for an instant to aim itself, and hurtled down the far side. It smashed directly into the lead cart. Projectile and victim shattered in an abrupt burst of sound.

  Morrison leaped up. “What the hell?”

  “That's it!” Perine screamed, dancing around and waving his skinny arms. “It's Detroit!”

  A second Detroit search-bug appeared, hesitated as it took in the situation, and then flung itself furiously at the retreating Pittsburgh carts. Fragments of tungsten scattered everywhere—parts, wiring, broken plates, gears and springs and bolts of the two antagonists flew in all directions. The remaining carts wheeled screechingly; one of them dumped its load and rattled off at top speed. A second followed, still weighed down with tungsten. A Detroit search-bug caught up with it, spun directly in its path, and neatly overturned it. Bug and cart rolled down a shallow trench, into a stagnant pool of water. Dripping and glistening, the two of them struggled, half submerged.

  “Well,” O'Neill said unsteadily,“we did it. We can start back home.” His legs felt weak. “Where's our vehicle?”

  As he gunned the truck motor, something flashed a long way off, something large and metallic, moving over the dead slag and ash. It was a dense clot of carts, a solid expanse of heavy-duty ore carriers racing to the scene. Which factory were they from?

  It didn't matter, for out of the thick tangle of black dripping vines, a web of counter-extensions was creeping to meet them. Both factories were assembling their mobile units. From all directions, bugs slithered and crept, closing in around the remaining heap of tungsten. Neither factory was going to let needed raw material get away; neither was going to give up its find. Blindly, mechanically, in the grip of inflexible directives, the two opponents labored to assemble superior forces.

  “Come on,” Morrison said urgently. “Let's get out of here. All hell is bursting loose.”

  O'Neill hastily turned the truck in the direction of the settlement. They began rumbling through the darkness on their way back. Every now and then, a metallic shape shot by them, going in the opposite direction.

  “Did you see the load in that last cart?” Perine asked, worried. “It wasn't empty.”

  Neither were the carts that followed it, a whole procession of bulging supply carriers directed by an elaborate high-level surveying unit.

  “Guns,” Morrison said, eyes wide with apprehension. “They're taking in weapons. But who's going to use them?”

  “They are,” O'Neill answered. He indicated a movement to their right. “Look over there. This is something we hadn't expected.”

  They were seeing the first factory representative move into action.

  As the truck pulled into the Kansas City settlement, Judith hurried breathlessly toward them. Fluttering in her hand was a strip of metal-foil paper.

  “What is it?” O'Neill demanded, grabbing it from her.

  “Just come.” His wife struggled to catch her breath. “A mobile car— raced up, dropped it off—and left. Big excitement. Golly, the factory's—a blaze of lights. You can see it for miles.”

  O'Neill scanned the paper. It was a factory certification for the last group of settlement-placed orders, a total tabulation of requested and factory-analyzed needs. Stamped across the list in heavy black type were six foreboding words:

  ALL SHIPMENTS SUSPENDED UNTIL FURTHER NOTICE

  Letting out his breath harshly, O'Neill handed the paper over to Perine. “No more consumer goods,” he said ironically, a nervous grin twitching across his face. “The network's going on a wartime footing.”

  “Then we did it?” Morrison asked haltingly.

  “That's right,” O'Neill said. Now that the conflict had been sparked, he felt a growing, frigid terror. “Pittsburgh and Detroit are in it to the finish. It's too late for us to change our minds now—they're lining up allies.”

  IV

  Cool morning sunlight lay across the ruined plain of black metallic ash. The ash smoldered a dull, unhealthy red; it was still warm.

  “Watch your step,” O'Neill cautioned. Grabbing hold of his wife's arm, he led her from the rusty, sagging truck, up onto the top of a pile of strewn concrete blocks, the scattered remains of a pillbox installation. Earl Perine followed, making his way carefully, hesitantly.

  Behind them, the dilapidated settlement lay spread out, a disorderly checkerboard of houses, buildings, and streets. Since the autofac network had closed down its supply and maintenance, the human settlements had fallen into semibarbarism. The commodities that remained were broken and only partly usable. It had been over a year since the last mobile factory truck had appeared, loaded with food, tools, clothing, and repair parts. From the flat expanse of dark concrete and metal at the foot of the mountains, nothing had emerged in their direction.

  Their wish had been granted—they were cut off, detached from the network.

  On their own.

  Around the settlement grew ragged fields of wheat and tattered stalks of sun-baked vegetables. Crude handmade tools had been distributed, primitive artifacts hammered out with great labor by the various settlements. The settlements were linked only by horse-drawn carts and by the slow stutter of the telegraph key.

  They had managed to keep their organization, though. Goods and services were exchanged on a slow, steady basis. Basic commodities were produced and distributed. The clothing that O'Neill and his wife and Earl Perine wore was coarse and unbleached, but sturdy. And they had managed to convert a few of the trucks from gasoline to wood.

  “Here we are,” O'Neill said. “We can see from here.”

  “Is it worth it?” Judith asked, exhausted. Bending down, she plucked aimlessly at her shoe, trying to dig a pebble from the soft hide sole.“It's a long way to come, to see something we've seen every day for thirteen months.”

  “True,” O'Neill admitted, his hand briefly resting on his wife's limp shoulder. “But this may be the last. And that's what we want to see.”

  In the gray sky above them, a swift circling dot of opaque black moved. High, remote, the dot spun and darted, following an intricate and wary course. Gradually, its gyrations moved it toward the mountains and the bleak expanse of bomb-rubbled structure sunk in their base.

  “San Francisco,” O'Neill explained. “One of those long-range hawk projectiles, all the way from the West Coast.”

  “And you think it's the last?”Perine asked.

  “It's the only one we've seen this month.” O'Neill seated himself and began sprinkling dried bits of tobacco into a trench of brown paper. “And we used to see hundreds.”

  “Maybe they have something better,” Judith suggested. She found a smooth rock and tiredly seated herself. “Could it be?”

  Her husband smiled ironically. “No. They don't have anything better.”

  The three of them were tensely silent. Above them, the circling dot of black drew closer. There was no sign of activity from the flat surface of metal and concrete; the Kansas City factory remained inert, totally unresponsive. A few billows of warm ash drifted across it and one end was partly submerged in rubble. The factory had taken numerous direct hits. Across the plain, the furrows of its subsurface tunnels lay exposed, clogged with debris and the dark, water-seeking tendrils of tough vines.

  “Those damn vines,” Perine grumbled, picking at an old sore on his unshaven chin. “They're taking over the world.”

  Here and there around the factory, the demolished ruin of a mobile extension rusted in the morning dew. Carts, trucks, search-bugs, factory representatives, weapons carriers, guns, supply trains, subsurface projectiles, indiscriminate parts of machinery mixed and fused together in
shapeless piles. Some had been destroyed returning to the factory; others had been contacted as they emerged, fully loaded, heavy with equipment. The factory itself—what remained of it—seemed to have settled more deeply into the earth. Its upper surface was barely visible, almost lost in drifting ash.

  In four days, there had been no known activity, no visible movement of any sort.

  “It's dead,” Perine said. “You can see it's dead.”

  O'Neill didn't answer. Squatting down, he made himself comfortable and prepared to wait. In his own mind, he was sure that some fragment of automation remained in the eroded factory. Time would tell. He examined his wristwatch; it was eight-thirty. In the old days, the factory would be starting its daily routine. Processions of trucks and varied mobile units would be coming to the surface, loaded with supplies, to begin their expeditions to the human settlement.

  Off to the right, something stirred. He quickly turned his attention to it.

  A single battered ore-gathering cart was creeping clumsily toward the factory. One last damaged mobile unit trying to complete its task. The cart was virtually empty; a few meager scraps of metal lay strewn in its hold. A scavenger … the metal was sections ripped from destroyed equipment encountered on the way. Feebly, like a blind metallic insect, the cart approached the factory. Its progress was incredibly jerky. Every now and then, it halted, bucked and quivered, and wandered aimlessly off the path.

  “Control is bad,” Judith said, with a touch of horror in her voice. “The factory's having trouble guiding it back.”

  Yes, he had seen that. Around New York, the factory had lost its high-frequency transmitter completely. Its mobile units had floundered in crazy gyrations, racing in random circles, crashing against rocks and trees, sliding into gullies, overturning, finally unwinding and becoming reluctantly inanimate.