Arc Riders

by David Drake

  Human color vision could detect variations in shade that were a matter of a few angstroms—a few hundred millionths of a centimeter. Only the most sensitive electronic devices were capable of finer discrimination. Chun used her eyes as a shorthand method of measuring the sensors’ current output against electronic perceptions before the attack.

  She nodded to Roebeck. “We can call Tim in,” she said. “We’ll have warning before another vehicle locks on to us.”

  Roebeck stood up and bent backward to stretch. “I’m going to see what the damage looks like,” she said.

  “You’ll learn more from the display,” Chun said.

  “I’ll use the display,” Roebeck said. “I want to see what happened, too.”

  North America

  Circa 10,000 BC

  When they entered the shade of the trees, Rebecca Carnes felt fear close in around her

  There wasn’t anything wrong with the forest itself. A squirrel scolded from the opposite side of a tree bole, implying that there was nothing more dangerous around than the two time travelers. The woods were where the enemies in Carnes’ mind lurked, though. They were preparing to rake her with automatic rifles and rocket-propelled grenades, then melt away into the deeper darkness….

  “Mr. Barthuli?” she said.

  She didn’t know what the proper form of address might be. The ARC Riders didn’t appear to be terribly rank-conscious. A good thing, as far as Carnes was concerned. She’d met army nurses who were more concerned with being officers than in helping their patients. Carnes’ stomach turned at people who worried about status when there was a job to be done.

  The analyst turned his head. “Major?” he said. He was a slender, not unhandsome man with the features of a bird of prey. His expression was friendly whenever Carnes looked at him, but she always had the impression that he stood behind a sheet of thick glass.

  “I don’t know how to use this gun,” Carnes said, holding up the pistol Barthuli had taken from her armor. It felt light and flimsy, as if it were no more than a plastic shell. It seemed to have two parallel barrels, cast in one piece with the weapon’s receiver and smooth grips.

  She stopped walking. “I… had a problem with a gun just before you picked me up,” she went on. “I hadn’t checked it. I don’t like to make the same mistake twice.”

  “Pauli fusses like a mother hen,” Barthuli said. “Sometimes I think he’s worse than Nan herself.”

  Though the analyst sounded dismissive, he turned the weapon slightly in Carnes’ hand so that they were both looking at the left side. The dial there was milled on the outer edge and about an inch in diameter. Rather than increments, 90 percent of the dial’s circuit was marked with a color band that changed clockwise in the order of the optical spectrum.

  “Tim Grainger didn’t say anything, but I think he worries, too,” Carnes said reflectively.

  Barthuli nodded. “Tim’s afraid that one of us will need help and he won’t be present to give it,” he said. “I believe he thinks of us as his family, his clan. He doesn’t really have friends, though I can’t imagine a friend who’d do more for any of us than Tim would.”

  The analyst smiled at Carnes through a psychic barrier no one would ever be able to penetrate. “I don’t have friends, either, of course, Major. But that’s a flaw in me.”

  “I prefer Rebecca,” Carnes said. “Though you can call me whatever makes you comfortable.”

  Barthuli chuckled. “It won’t work,” he said, “but it’s kind of you to try. Now—”

  He pointed. The red end of the color band was vertical. The gray dividing segment was counterclockwise of it, with deep violet beyond that.

  “The weapon creates a difference tone of ultra-low frequency at the point of aim,” Barthuli explained. “Minimum setting is 160 dB, which is generally sufficient. Simply point the muzzle and pull the trigger.”

  He indicated a standard trigger.

  “To increase the output, rotate the dial.” Barthuli’s hands were unexpectedly large, though shapely. The tip of his index finger rolled the dial upscale, then back to its original setting. “But I really don’t imagine we’ll need to be armed. Shall we proceed?”

  Birds flapped noisily in the foliage overhead. Carnes hadn’t been able to hear them when her feet and her companion’s shuffled through the dead leaves.

  “Sure, I just wanted to—” She’d almost said be prepared. She wasn’t prepared. “To know, that’s all.”

  They resumed walking toward the top of the hill. It was farther than it had seemed from where Weigand waited with the suits, but a slab of bare rock beneath a huge oak suddenly announced that they’d reached their goal.

  Barthuli hopped onto the slab. He moved his gray box in an arm’s-length panorama.

  Carnes assumed the box was some sort of camera. She kept a comfortable distance from the analyst, so as not to interfere—and not be bumped by the gadget. She’d noticed that photographers were generally oblivious of their immediate environment.

  For that matter, she’d noticed that photographers often didn’t see a scene until they viewed their print or videotape long afterward.

  In the present case, that would have been a terrible shame. The landscape was beautiful with a touch of weirdness that Carnes couldn’t identify for some moments.

  She and Barthuli stood on a bluff a hundred feet above the river flowing swiftly in the near distance. The water winking beyond the treetops was a cloudy blue-white from the influx of melted ice that fed it only a few hundred miles to the north.

  Though the limestone bluff was steep, trees of varying size had found crevices to spout in. Their foliage, leaves and needles both, blurred the details of the slope.

  The floodplain was narrow and willow-choked, even now at low water in the summertime. Or was it low water, when meltwater fed the stream rather than runoff from rains in the upper tributaries? The eastern margin, in the far distance, was hazy but clearly lower than that here on the west side of the river.

  “I’ve never seen so much land without anything human in it,” Carnes said. “Something felt wrong about what I was seeing. It’s just that.”

  Instead of commenting, Barthuli touched unseen controls on the edges of his gray box. The air before him shimmered, though Carnes couldn’t see the interference patterns as images from where she stood.

  “Do you know, Rebecca?” the analyst said. Carnes hadn’t heard so much animation in his voice before. “Do you know, I think you’re wrong!”

  The pine to their immediate left grew from a ledge forty feet below them. Barthuli took Carnes by the hand and pointed her whole arm past the ragged top of the tree. A wisp of gray smoke rose fitfully, dissipating long before it reached the clouds. The source was lost in the willows and alders close beside the river.

  “I scanned for anomalies,” Barthuli explained. He gestured with the gray box as he released Carnes’ hand. “I thought the hunting bands were too thinly scattered for us to have a real likelihood of locating one, but it seems our luck was with us.”

  He placed the camera in a pocket of his coveralls and eyed the immediate slope. Gripping an inch-thick sapling crowned with oak leaves, he slid down sideways to an outcrop four feet below the top of the bluff.

  “Wait!” Carnes said. It had taken her a moment to realize what Barthuli really intended. “Barthuli, we can’t possibly get down there and back up in an hour. For pity’s sake, we ought to be starting back right now!”

  The analyst let himself skid to a considerable pine tree a dozen feet lower. He stopped himself by grabbing its trunk, then sidled past a sheer drop of twenty feet to a more accessible slope. Carnes could see only the top of his head.

  Barthuli paused and looked up at her. “Rebecca, I won’t have anotherchance to see this culture. They should be Clovis hunters, you know—virtually identical to the folk who originally crossed into the continent over the Bering Land Bridge?”

  “Gerd,” Carnes said, hugging her torso at diaphragm level as
a protective reflex. “Please. We’ve got to get back, to Pauli and to the capsule.”

  Barthuli shrugged. “Rebecca,” he said, “lives aren’t eternal. I’m perhaps more constantly aware of that than others of you, but it’s true for everyone. Never give up a chance to learn, while your brain can accept the knowledge. Please, come along with me.”

  “Gerd, people depend on you!” Carnes said.

  Barthuli shrugged again. “Tell Pauli that I won’t be any longer than I need be,” he said. He slid down to another pine and vanished behind its trunk. Carnes could hear twigs crackling for a short while.

  She turned and started back to where Weigand waited with the armor. After a moment, she broke into a run.

  Eurasia

  Circa 50,000 BC

  “The hostiles weren’t very good, were they?” Grainger said as he and Roebeck viewed TC 779’s external damage with their faceshields up. “They got buck fever and missed an easy one.”

  The initial jet of plasma struck to the left of the hatch. It had dug a fist-deep gouge through the outer skin and hull core. The cavity was of greatest diameter at its maximum depth, where it belled out like the top of a thundercloud. The inner plating had reflected the bolt rather than absorbing the energy.

  “I was thinking that,” Roebeck agreed. “We’ve got to assume they’ll still have a full complement if we run into them again, though.”

  Grainger shrugged. “Numbers within reason aren’t a problem,” he said. “So long as you’re quick and keep your muzzle down.”

  He smiled. The expression made him look boyish for the moment before his face settled back into its normal grim lines.

  Where the bolt first hit, damage was total. From that near-puncture, the stream of plasma trailed to the left and upward, doing greatly diminished harm: after the first instant, TC 779’s automatic defenses had wrapped the vehicle in a dense magnetic flux. The shielding repelled the stripped nitrogen atoms the way static-charged hairs are flung away from the scalp.

  The outer skin showed the track of the plasma beam as orange-peel crinkling. Occasionally the scar deepened to a crater. These were spots where there’d been a preexisting flaw, or a flux eddy had permitted a portion of the charged particles to strike the metal directly.

  The other shooter fired later than his partner—only by a temporal hair’s breadth, but enough that his beam struck after the capsule’s shielding had risen to nearly full intensity. The plasma blasted a divot as broad as a soup plate from the hatch just off-center, then slid left at a flatter angle than that of the first weapon. Where the second track crossed the first, it blew away a chunk of the ceramic core. A penumbra of circuitry beyond the region of total destruction was crumbled.

  “We’re lucky the hatch still works,” Roebeck said. “I know the theory about changing it to manual operation, but I wouldn’t look forward to trying it.”

  “For a target like this, I’d have coupled the triggers so the weapons fired together,” Grainger said. “And pulses, for Christ’s sake, not close your eyes and mash the trigger!”

  “They had three firing for a moment,” Roebeck said. She squatted to view the vehicle’s underside. “I don’t know whether the third one simply missed, or our shielding deflected the beam completely because it came in too low.”

  “Cowboys,” Grainger muttered. His gauntleted right hand caressed the grip of his fléchette gun.

  “The most serious damage is…” Chun said over the helmet communicators. A beam of red light from a lens on Roebeck’s left shoulder illuminated the point where the two plasma tracks crossed. “… here. Other places we’ve lost circuits, kilometers of them, but it’s nothing we can’t bypass for now. Here we lost the temporal bus.”

  “Is the spatial bus all right?” Roebeck asked in a thin voice. All her emotions were filtered gray by the fear Chun would reply no.

  “It’s on the other side of the vehicle,” Chun said. “It didn’t receive any damage at all.”

  Roebeck felt her muscles relax. The world brightened around her again. She’d known they were looking at weeks of work, maybe months, in replacing circuits and building shunts. TC 779 wouldn’t have anything like its normal delicacy of maneuver. Chances were the apparent duration of displacements would lengthen, maybe double, because the vehicle had to generate some fields in sequence rather than simultaneously.

  But time it took to repair the capsule didn’t matter; the team would be that much older when they confronted the revisionists and perhaps the hostile ARC Riders, that was all. The physical labor of the repairs mattered even less.

  Nobody joined the Anti-Revision Command because the work was less demanding than the 26th-century norm. ARC Riders were expected to do whatever the job required. If that meant (as it occasionally did) living for months in a community where the life expectancy—for those who survived infancy—was less than thirty years, so be it.

  Roebeck chuckled. Thirty years was probably a close approximation of the life span of the humans on this horizon—where she’d be trapped unless they did get the vehicle temporally mobile again.

  Without a bus, there would have been billions of connections to make before the computer could distribute commands. The three of them couldn’t have done the job in ten lifetimes.

  “Until…” she said aloud.

  “I have a routing plan for repairs,” Chun said. “Whenever you’d care to see it…”

  There was a touch of asperity in her voice. Quo simply couldn’t understand why anybody would need to look at an actual object when the combination of computer and display would provide the information in infinite detail and clarity.

  “Okay, we’re coming in,” Roebeck said. The repairs couldn’t be done by the computer, though. She wondered how many Maxwell Field sorters remained in the locker. Probably none, and the weather here wasn’t likely to remain this comfortable throughout their stay.

  “Nan,” Grainger said quietly. “Take a look.”

  She turned, expecting to see Grainger pointing. His left arm remained at his side, while the right crooked his gun/EMP generator to his armored chest. “On the hill there,” he said.

  Roebeck followed the line of Grainger’s eyes to a knoll five hundred meters down the valley. Rock grayed the mantle of long yellow grass. A flat-topped tree twisted from a crevice. Roebeck thought it might be a fig. “What do you—” she began.

  “Lower your faceplate and use some magnification,” Grainger said. “I caught the movement.”

  Roebeck obeyed with a smooth, slow motion, much as she would have positioned her hand to snatch a fly from a table-top. She locked the visor in place and boosted optical magnification by ten powers, enough that the edges of her field of view precisely framed the knoll.

  “I don’t…” she said, and then she did see the face looking at her through a screen of sere grass blades. “Yes.”

  At × 100 magnification, she could see blue eyes glinting from beneath heavy brows. There was no facial hair, but the figure’s forearms—the woman’s forearms—were covered with a russet pelt.

  “ARC Central isn’t going to like this,” Grainger said with a joking lilt. “Us in a human-occupied location, and we haven’t parked the capsule out of phase.”

  A child’s face peeped over the female’s shoulder. The watchers were as still as the stone on which they crouched.

  “I don’t know about you,” Roebeck said, “but I’d be more than happy if I could displace straight to Central and take my punishment. Since we can’t…”

  She raised her faceshield again. “Let’s see what Quo suggests, and then figure out how we’re going to execute the plan.”

  She gestured Grainger inside the vehicle. As she followed him, she looked back toward the knoll. The faces had vanished.

  North America

  Circa 10,000 BC

  Pauli Weigand glanced up at the trees, pursing his lips to try again to raise Barthuli on the radio. He saw Major Carnes jogging toward him with a set expression. She was alone.<
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  Carnes hadn’t taken a headband with her. That was Weigand’s mistake, the way a lot of things were Weigand’s mistake, but it didn’t bother him for the moment. Now there was trouble, so he had a job to do.

  He checked his shoulder weapon. There was a tanglefoot round in the chamber. That was as good a choice as gas, because he didn’t have a clue yet as to what the problem was. Maybe a bear? There were bears here, he knew.

  Weigand pulled on his boots. He’d been digging his bare toes into the ground, and traces of rich loam still clung to them.

  “Barthuli went down to the riverside,” Carnes said, breathing through her mouth between gasped phrases. “He says there’s a camp of Indians down there and he wants to see it!”

  “I swear, Gerd’s got no more sense than a, aw, I don’t know what,” Weigand said. “He’s all right, though?”

  “He was fine when he went behind the trees,” Carnes said. She was getting her breathing under control. “I’m sorry. I couldn’t make him come back without…”

  Without shooting him, probably, and Major Carnes wasn’t the first to think about shooting Barthuli. “It’s all right,” Weigand said, smiling ruefully at Carnes. “Not a thing anybody can do when Gerd gets an idea. But he’s everything you could ask for otherwise.”

  Weigand considered putting his armor on. If he wore the suit, he’d be completely safe from anything Stone Age locals could do. It wouldn’t make the hill any easier to climb, though, and if the river had cut the other side steeper, he’d have a devil of a time going down.

  That wasn’t the real downside, though. Weigand would be safe and so would the major if she suited up, whether she came along or stayed back here. Barthuli wasn’t in armor, though. If the locals decided that the stranger had brought a couple demons into their village, things might get terminal before Weigand could cover the area with gas.

  “I don’t even know there’s Indians down there,” Carnes said carefully. “Barthuli showed me smoke, but he was just guessing that it came from a camptire. He called them Clovis hunters.”