Spinneret

Chapter 7

Astra's sun was peeking over the eastern horizon as Carmen eased open the throttle to send the flyer drifting smoothly into the air. Hafner kept his eyes on the handful of displays and meters as she shifted from vertical to horizontal flight, but if the maneuver was in any way a tricky one, it wasn't apparent. On the contrary; the more he watched, the more it seemed that a bare handful of the dozens of controls were all she needed to guide the craft. He wondered what the others did, but their glowing labels were more confusing than informative. Eventually, he broke down and asked her.

"Most of those are used only when the flyer is in its spacecraft mode," Carmen told him, raising her voice over the low rumble of the repulsers.

"Ah." At least they wouldn't be needing that capability today, Hafner thought.

"Have you decided yet where you'll want me to land?" Carmen asked.

"If we have the time, perhaps we can circle the cone first. I need to find a good area to sample."

She nodded and for a few minutes neither of them spoke.

Looking out his window, Hafner let his eyes drift over the landscape. Just south of their path Unie was a collection of tannish blocks set on slightly darker tannish ground. Much farther to the south the white-edged peaks of the Kaf Mountain range provided only a slight contrast of coloration; and most of that, he knew, was due to shadows and other basically optical effects. No ferric red, no cupric green—the whole territory had all the washed-out blandness of a Hawaiian hotel beach. His eyes drifted ahead to Crosse … and narrowed a bit. "Carmen," he called, "can you slow down just this side of Crosse?"

She glanced curiously at him. "Sure. Anything wrong?"

"I think I can see the outline of a shallow circular depression between the river and the Unie-Crosse road. I want a better look at it."

"What is it, a dead volcano or something?" Carmen asked, shifting the flyer's course toward the area he'd indicated.

"More likely an old meteor crater," he said, peering down. "A little higher, please

… yes … yes, damn it. That's what it is, all right. Too circular to be anything else.

Thanks; we can go now."

The flyer tilted slightly to her side and he saw her take a quick look for herself before resuming their horizontal flight. "You sound annoyed," she ventured. "Are you worried about meteors hitting us?"

"Yes, but not the way you're thinking." He waved toward her window. "Teardrop Lake over by Ceres. If you look at it on satellite photos you can see that it's a circular depression that's been eroded by the rivers entering and leaving. The Dead Sea southeast of Olympus is the same thing plus what appear to be fault-line appendages. Even Splayfoot Bay shows a deep area in the center that's basically circular. This planet has been literally pelted with rocks over maybe the last half million years—not surprising when you consider how close we are to the asteroid belt here. So where's all the metal those meteorites brought down with them?"

Watching her, he noted with approval the furrowing of her forehead. At least she recognized the paradox there; some he'd talked to hadn't even made it that far.

"Well … could the Rooshrike survey data be wrong?"

"That's the most likely explanation," Hafner nodded. "The problem is that we've done our own spot checks since then. Our equipment doesn't have their halfkilometer range, but the chunk of rock that dug out Splayfoot Bay ought to have left some of itself scattered through the topsoil."

"Then maybe the asteroids that hit were just as metal-poor as Astra," she suggested. "If the whole system formed from the same cloud of dust … no.

Doesn't work, does it?"

"Not when we know the Rooshrike are mining metals on the first planet," Hafner agreed. "Besides which, some of the smaller asteroids were analyzed by the original survey team and turned out to have a reasonable metal content. No, whatever happened here happened only to Astra."

They rode in silence for the next few minutes. Ahead, the hazy cone of Mt.

Olympus gradually became sharper, the low angle of sunlight showing first the gross and finally the fine structure of its surface. Hafner watched with undivided interest, eyes probing for clues as to the type of lava that had formed it. The steepness of the cone suggested viscous lava flows, which on Earth would mean a predominance of andesitic rock. On the other hand, he could see little evidence of the surface characteristics that usually accompanied that type of lava. Still, if the volcano had been dormant for a long time, erosion would have altered many of the visual reference points. As with everything else in geology, there was ultimately no substitute for physically digging out the rocks and analyzing them.

"What about some weird process that breaks the metal down?" Carmen spoke up abruptly. "A nuclear fission sort of thing. Maybe it's some organism's way of producing energy."

"Chemical energy is a lot safer to work with," Hafner grunted. An interesting idea

… but the flaw was easy to find. "Besides, that would only get rid of elements in the bottom half of the periodic table. Sodium is far too light a metal to fizz, but Astra hasn't got any of it, either."

"Oh. Wait a minute." She threw him a puzzled look. "No sodium either? But I thought Astra's ocean was salty."

"Not really. There's a fair assortment of stuff dissolved in it, but none of it strictly qualifies as salt. A salt, you see, is formed by replacing the hydrogen atom in an acid by a metal, as in hydrochloric acid to sodium chloride. Without metals, the acids remain as is or make bonds with oxygen or silicon." He shook his head.

"We're sitting on a genuine treasure trove of strange chemistry here. Compounds that wouldn't last five seconds on Earth are just lying around waiting to be examined. I think we're up to eighteen brand-new carbon compounds alone since we've landed."

"Anything valuable?"

"You mean in terms of sending to Earth? So far, no. But we haven't even scratched the surface. We'll find something useful here—I'm sure of it."

"I hope you're right." She paused. "All right, I'm starting a clockwise circuit of Olympus. Pick your spot this time around, because I've got to get the flyer back soon."

"Right." A metallic glitter a few kilometers south of the cone caught Hafner's eye; but even as he opened his mouth to shout the discovery he realized what it was.

Even with the incredible scarcity of metal, no one had yet found it worthwhile to come out here and scrape up all the tiny fragments of steel and magnesium scattered across the landscape by the ill-fated Flyer Two. Shivering, he resolutely turned his eyes back to the volcano.

He found the spot he was looking for in less than half a circuit: a small lump halfway up the slope that might indicate an old pipe vent. "There," he told Carmen, pointing. "It's at least a ten-degree slope, though—can this thing handle that?"

"Easily," she told him. The dull background roar changed pitch as she switched back to vertical thrusters. Three minutes later they were down.

Hafner's core-sampling equipment, while bulky, was not very heavy, and it took only fifteen minutes to unload it from the flyer and move it out of range of the repulsers. "Now you sure you're going to be all right?" Carmen asked as he dropped the last load of bracing bars onto his pile.

"I'll be fine," he assured her. "It's not like this is my first time on an all-day expedition, you know. I know what I'm doing."

"Fine. Okay, then, I'll be back to pick you up around twenty hundred. "Bye."

It was closer to twenty-one hundred by the time she returned, but the delay didn't especially matter to Hafner. With all his samples taken, he had nothing to do for the moment but sit on the ground and brood … and brooding he could do anywhere.

"Zilch," he told Carmen as the flyer lifted off. "Not a single bit of metal in any of the half-dozen samples I ran."

"So that means Astra's magma is metal-free, too?" she asked.

"I don't know. Maybe I just got anomalous samples. The rock looked more heattreated than actually melted—and, no, I don't know what could account for that.

Say, would you take me the rest of the way around before we head back? I might as well look for a second test site while we're here."

The flyer tilted slightly as she complied. "I'm afraid it'll probably be a month or so before you'll be able to get back—I don't think I'd better pull this trick again."

He grunted. "Unless the borings show something promising it'll be a good stretch longer than that."

For a moment he studied the ground in silence. Directly ahead the blue water of the Dead Sea glinted in the fading sunlight; a couple of kilometers to the west of it he again saw the wreckage of Flyer Two. To his immediate right Olympus sat profiled against the multicolored western sky, and he noticed for the first time that the southern slope of the volcano seemed climbable, a bit of information he filed away for future reference. As the flyer continued its slow circle, the Dead Sea began to disappear from his view. He glanced one final time at it … and frowned.

"Carmen, take us back to the east, would you? There's something funny in the Dead Sea."

"What is it?" Carmen asked as the flyer banked to the left.

"I'll let you know in a minute."

Seconds later they leveled out, bringing the Dead Sea into Hafner's view again.

"Look down there," he told her. "The Sea's northwestern shore. See it?"

"You mean that white stuff? Looks like the offshore mineral deposits near the colony."

"Right. Like its namesake, our Dead Sea hasn't got any outlets, so minerals collect there. As the water evaporates, some of them are left to encrust the shoreline. But why only on the northwestern side?"

"Well … why do the offshore deposits only show up near Splayfoot Bay?" she countered.

"Presumably they're just more visible there because the continental shelf has a very gradual slope," he said, with waning enthusiasm. "You're right; it's probably something like that. Let's go on home—I think I've had it for one day." A fast dinner and right to bed, he told himself firmly. For once, the samples can wait till tomorrow.

An hour later he was at the lab, eating a sandwich at his desk as the analyzers chugged industriously away. The results, when they finally came, were painfully predictable: no metal, of any sort, in any of the borings.