Alvin had trouble gathering Mudfoot, who ignored the boy's umble calls while wandering across the conference table, poking a whiskered nose into debris from the meeting. Finally, the tytlal stood up on his hind legs to peer at the frozen projection last sent by Kaa's probe, the image of a privacy wasp. Mudfoot purred with curiosity.

"Niss," Gillian said in a low voice.

With an audible pop, the pattern of whirling, shifting lines came into being nearby.

"Yes, Dr. Baskin? Have you changed your mind about hearing my tentative conjectures about Uriel's intricate device of spinning disks?"

"Later," she said, and gestured at Mudfoot. Gillian now realized the tytlal was peering past the blurry display of the privacy wasp, at something in the scene beyond.

"I'd like you to do some enhancements. Find out what that little devil is looking at."

She did not add that she had detected something on her own. Something only a psi-sensitive would notice. For the second time, a faint presence could be felt-vague and ephemeral-floating ever so briefly above Mudfoot's agitated cranial spines. She could not be sure, but whatever it was had a distinctly familiar flavor.

Call it Essence of Tymbrimi.

Kaa THERE WAS NO MORE TO ACCOMPLISH IN THE CAVE. The probe appeared to be dead. Even if it came back to life, any conversation with the natives would be handled from Streaker's end. Meanwhile, it was past time to return to the habitat. Kaa had a team he had not seen in days.

A human couple might have paused before exiting the little grotto, looking around to imprint the site of their first lovemaking. But not dolphins. Neo-fins experienced nostalgia, just like their human patrons, but they could store sonar place images in ways humans had to mimic with recording devices. Streaking outside, joining Peepoe under bright sunshine, Kaa knew the two of them could revisit the cave anytime they chose, simply by bringing their arched foreheads together-re-creating its unique echoes in that ancient gulf of memory some called the Whale Dream.

It felt good to dash across the wide sea again, with Peepoe's lithe body sharing every kick and leap in perfect unison. Motion equaled joy after any long confinement to machinery and closed s.p.a.ces.

On the outward trip, their swim had been exquisite, but tempered by a taut, s.e.xual tension. Now there were no secrets, no conflicting desires. Most of the return journey was spent in silent bliss-like a simple mated pair from presapient days, free of the gifts and burdens of uplift.

Finally, with the habitat drawing near, Kaa felt his mind slip reluctantly back into Anglic-using rhythms. Compelled to speak, he used the informal click-squeal dialect fins preferred while swimming.

"Well, here it comes," he sonar-cast during the underwater phase of their next splash-and-surge cycle. "Back to home and family . . . such as they are."

"Family?" she replied skeptically. "Brookida, perhaps. As for Mopol and Zhaki, wouldn't you rather be related to a penguin?"

Is my opinion of them so obvious? After breaching for air, Kaa tried making light of things with a joke.

"Oh, I give those two some credit. With luck, they won't have set the ocean on fire while we're gone."

Peepoe laughed, then added, "Do you think they'll be jealous?"

Good question. Dolphins could not conceal interpersonal matters like humans, with their complex games of emotional deceit. By sonar-scanning each other's viscera, one seldom had to guess who slept with whom.

Envy wouldn't be a problem if I established clear authority from the start, both as an officer and as senior-ranking male.

Unfortunately, chain of command was a recent, humanimposed concept. Underneath, bull dolphins still felt ancient drives to jostle over status and breeding rights.

In fact, Peepoe's choice might reinforce Kaa's position atop the little local hierarchy. Though I shouldn't need help. Not if I were a real leader.

"Jealous." He pondered, thrusting harder with his flukes, till his beak pushed their shared shock wave, drawing her along in his wake. "Those two are highly s.e.xed, so maybe they will be. But at least this way Zhaki and Mopol should stop bothering you with hopeless propositions."

The young males had made relentless crude suggestions toward Peepoe from the first day she arrived, even brushing lewdly against her until Kaa had to rebuke them. While it was true that dolphins had a far different scale of tolerance for such behavior than humans-and Peepoe was capable of taking care of herself-in this case the pair were so persistent that Kaa had to dish out tail whacks to make them back off.

"Hopeless?" Peepoe asked in a teasing tone. "Now you're making a.s.sumptions. How do you know I'm monogamous? Maybe a little harem would suit me fine."

Kaa spread his jaws and aimed a nip at her nearest pectoral fin ... slow enough for her to slip aside, laughing, before his teeth snapped.

"Good," she commented. "Pacific Tursiops go in for that kinky stuff. But I prefer a nice and conservative Atlantean.

You're from Miami-Under, no? Born into an old-fashioned line marriage, I bet."

Kaa grunted. Even the sonar-based dialect of Anglic wasn't easy while speeding at full throttle.

"One of the Heinlein family variants," he conceded. "The style works better for dolphins than humans. Why? You looking for a line to marry into?"

"Mnn. I'd rather start a new one. Always hankered to be the founding matriarch of a nice little lineage-if the masters of uplift allow it."

That was the eternal Big If. No neo-dolphin could legally breed without permission from the Terragens Uplift Board. Despite the unusual freedoms humans had given their clients-voting rights and the trappings of citizenship-Earthclan was still bound by ancient Galactic law.

Improve your clients, went the basic code of uplift. . . . Or lose them.

"You gotta be kidding," he answered. "If any of us Streaker fins ever do make it home somehow from this crazed voyage, we'll never face another sapiency exam from the masters. We may be sterilized on the spot, for all the trouble we caused. Or else we're heroes, and it'll be sperm-and-seed donations for the rest of our lives, fostering almost the whole next neo-fin generation.

"Either way, it won't be cozy family life for any of us. Not ever."

He hadn't expected it to come out that way, with an edge of ironic bitterness. But Peepoe must have seen he was telling the truth. She continued keeping pace alongside, but her silence told Kaa how much it stung.

Great. Everything felt so fine . . . this wonderful water, the fish we s.n.a.t.c.hed for breakfast, our lovemaking. Would it have hurt to let her stay in denial for a while, dreaming of happy endings? Holding on to the fantasy that we might yet go home, and lead normal lives?

"Kaa!" Brookida's cry made the tiny habitat reverberate. "I'm glad you're back. Did your mission go well? Wait till you hear what I discovered by correlating pa.s.sive seismic echo scans from here to Streaker's sssite. I fed the raw data into one of Charles Dart's old programs to get tomography images of the subcrustal zone!" All that, on a single breath. It was what humans would call a "mouthful."

"That's great, Brookida. But to answer your question, our mission didn't go as well as we hoped. In fact, we have orders to pack everything up and break camp. Gillian and Tsh't plan to move the ship."

Brookida shook his mottled gray head. "Won't that risk giving away Streaker's position?"

"The site's already compromised. Dr. Baskin suspects the Jophur may be p-preoccupied, but that can't last."

It had been Kaa's mission to find out what the sooners knew about such things. Perhaps Uriel the Smith had some idea what the Jophur were up to. No one had blamed Kaa for the failure-not out loud. But he knew the ship's council -was disappointed.

I warned them to send someone better trained at spying.

He looked around. "Where are the others?"

Brookida let out a warbled sigh.

"Off joyriding on Peepoe's sled. Or else vandalizing the fishing nets of local hoons and qheuens."

d.a.m.n! Kaa cursed. He had ordered Zhaki and Mopol to stay within a kilometer of the dome, and restrict themselves to monitoring spy eyes already in place at Wuphon Port. Above all, they were supposed to avoid direct contact with the sooners.

"They got bored," Brookida explained. "Now that Streakerhas Alvin and other local experts aboard, our team is a bit redundant. It's why I've been tracing the subduction-zone magma flows. My first chance since Kithrup to test out an idea I had, based on Charles Dart's old research. You recall those strange beings who lived deep under Kithrup's crust? The ones with the weird, unp.r.o.nounceable species name?"

Peepoe spoke up. "You mean the Karrank-k%?" She did a creditable job of expressing the doubleaspirated slide tone at the end, sounding like a steam kettle about to explode.

"Yes, quite. Well, I'd been wondering what kind of ecosystem could support them down there. And it got me thinking . . ."

Brookida halted. Then all three dolphins whirled around as the wall segment behind them began emitting a low, sc.r.a.ping hum. The grating vibration hurt Kaa's jaw.

Soon, the entire habitat groaned to a rasping sonic frequency Kaa recognized.

It's a saser! Someone's attacking the dome!

"Harnesses!"

At his shouted command, they all dived toward the rack where heavy-duty tool kits were hung, ready for use. Kaa streaked through the open end of his well-worn apparatus, and felt its many control surfaces slide smoothly into place. A control cable snaked toward the neural tap behind his left eye. Robotic arms whirred as he jerked the harness free of its rack. Peepoe's unit popped loose just half an instant later.

A rough rectangle crept across the opposite wall, above and below the waterline, glowing hot.

"They're cutting through!" Peepoe cried.

"Breathers!" Kaa shouted. From the back of his harness, a hose swarmed over his blowhole, covering it with a moist kiss and tight seal. A blast of canned air tasted even more tinny than the recycled stuff within the dome. Kaa sent a neural command activating his torch cutter and saser, tools that could second as weapons in close combat. . . .

But they didn't respond!

"Peepoe!" He shouted. "Check your-"

"I'm helping Brookida!" she cut in. "His harness is stuck!"

Kaa slashed the water with his flukes, squealing a cry of frustration. With no better options, he interposed his body between theirs and the far wall . . . . . . which abruptly collapsed in a wave of pummeling froth.

Gillian I HAVE DISCOVERED SEVERAL THINGS OF INTEREST," the Niss Machine told Gillian, after she wakened from a brief induced sleep. "The first has to do with that wonderfully ostentatious native machine, built and operated by the urrish tinkerer, Uriel."

Sitting in her darkened office, she watched a recorded holo image of wheels, pulleys, and disks, whirling in a flamboyant show of light and action. Not far from Gillian, the ancient cadaver, Herbie, seemed to regard the same scene. A trick of shadows made the enigmatic, mummified face seem amused.

"Let me guess. Uriel created a computer."

The Niss reacted with surprise. Its spiral of meshed lines tightened to a knot.

"You knew?"

"I suspected. From the kids' reports, Uriel wouldn't waste time on anything useless or abstract. She'd want to give her folk something special. The one thing her founding ancestors absolutely had to throw away."

"Possession of computers. Good point. Dr. Baskin. Uriel could aim no higher than to be like Prometheus. Bringing her people the fire of calculation."

"But without digital cognizance," she pointed out. "An undetectable computer."

"Indeed. I found no reference to such a thing in our captured Galactic Library unit. So I turned to the precontact 2198 edition of the Encyclopedia Britannica. There I learned about a.n.a.log computation with mechanical components, which actually had a brief ascendancy on Earth, using many of the same techniques we see in Uriel's hall of spinning gla.s.s!"

"I remember hearing about this. Maybe Tom mentioned it."

"Did he also mention that the same thing can be achieved using simple electronic circuits? Networks of resistors, capacitors, and diodes can simulate a variety of equations. By interconnecting such units, solutions can be worked out for limited problems.

"It provokes one to consider the military potential of such a system. For instance, operating sneak-attack weapons without digital controls, using undetectable guidance systems."

The Niss holo performed a twist that Gillian interpreted as a shrug.

"But then, if the notion were feasible, it would have found its way into the Library by now."

There it was again. Even Tymbrimi suffered from the same all-pervading supposition-that anything worth doing must have been done already, over the course of two billion years. The a.s.sumption nearly always proved true. Still, wolfling humans resented it.

"So," Gillian prompted. "Have you figured out what Uriel is trying to compute?"

"Ah, yes." The line motif spun contemplatively. "That is, perhaps.

"Or rather . . . no, I have not." "What's the problem?" The Niss showed spiky irritation.

"My difficulty is that all the algorithms used by Uriel are of Terran origin."

Gillian nodded.

"Naturally. Her math books came from the so-called Great Printing, when human learning flooded this world, most of it in the form of pre-contact texts. A mirror image of what Galactic society did to Earth. On Jijo, we were the ones to unleash an overpowering wealth of knowledge, engulfing prior beliefs."

Hence also Gillian's recent, weird experience-debating the literary merits of Jules Verne with a pair of distinctly unhuman youngsters named "Alvin" and "Huck," whose personalities had little in common with the stodgy Galactic norm.

The Niss agreed, bowing its tornado of laced lines. "You grasp my difficulty, Doctor. Despite Tymbrimi sympathy toward Earthlings, my makers were uplifted as Galactic citizens, with a shared tradition. While details of my programming are exceptional, I was designed according to proven principles, after eons of Galactic experience refining digital computers. These precepts clash with Terran superst.i.tions- "

Gillian coughed behind her hand. The Niss bowed.

"Forgive. I meant to say, Terran lore."

"Can you give an example?"

"I can. Consider the contrast between the word,concepts discrete and continuous.

"According to Galactic science, anything and everything can be accomplished by using arithmetic. By counting and dividing, using integers and rational fractions. Sophisticated arithmetic algorithms enable us to understand the behavior of a star, for instance, by part.i.tioning it into ever-smaller pieces, modeling those pieces in a simple fashion, then recombining the parts. That is the digital way."

"It must call for vast amounts of memory and raw computing power."

"True, but these are cheaply provided, enough for any task you might require.

"Now look back at pre-contact human wolflings. Your race spent many centuries as semicivilized beings, mentally ready to ask sophisticated questions, but completely * lacking access to transistors, quantum switches, or binary ' processing. Until your great savants, Turing and Von Neumann, finally expressed the power of digital computers, generations of mathematicians had to cope by using pencil and paper.

"The result? A mix of the brilliant and the inane. Abstract differential a.n.a.lysis and cabalistic numerology. Algebra, astrology, and geometrical topology. Much of this amalgam was based on patently absurd concepts, such as j continuity, or aptly named irrational numbering, or the astonishing notion that there are layered infinities of the divisibly small."

Gillian sighed an old frustration.

"Earth's best minds tried to explain our math, soon after contact. Again and again we showed it was self-consistent. That it worked."

"Yet it accomplished nothing that could not be outmatched in moments by calculating engines like myself. Galactic seers dismissed all the clever equations as trickery and shortcuts, or else the abstract ravings of savages." She acceded with a nod.

"This happened once before, you know. In Earth's twentieth century, after the Second World War, the victors quickly split into opposing camps. Those experts you mentioned-Turing and von Whoever-they worked in the west, helping set off our own digital revolution.

"Meanwhile, the east was ruled by a single dictator, I think his name was Steel."

"Accessing the Britannica . . . You mean 'Stalin? Yes, I see the connection. Until his death, Stalin obstructed Russo-Soviet science for ideological reasons. He banished work on genetics because it contradicted notions of communist perfectibility. Moreover, he quashed work on computers, calling them 'decadent.' Even after his pa.s.sing, many in the east held that calculation was crude, inele- gant . . . only good for quick approximations. For truth, one needed pure mathematics."