15

Louis roamed the narrow, serpentine corridors of Long Shot looking for distraction because Hindmost refused to be rushed. Louis looked for weapons, too, not that, if it came to combat, one ship could prevail against whole fleets. Long Shot’s advantage was its speed.

“Hindmost’s Voice,” Louis called. “Review your orders.”

“If any ship emerges from hyperspace nearer to us than a light-hour, initiate an immediate ten-light-day maneuver outward from the star through hyperspace. Repeat as needed until I detect no ship within a light-hour.”

“Very good.” Louis turned another corner, plunging deeper into the ship. Kzinti had held this ship for … he did not know how long. If only for a day, there would be some weapons aboard. Tunesmith would have added weapons, too.

Louis doubted he would recognize a protector’s weapon design.

He squirmed through a narrow passageway into yet another equipment room. Except for some stepping discs and float plates Tunesmith must have stowed in the corner, photonics racks filled the space. To judge from the power converters and backup fuel cells, whatever this gear did drew a lot of power. Fat fiber-optic bundles ran between racks and out the hatch into the passageway he had just left. The ship was filled with rooms like this.

Much of it decoy equipment, he had come to realize. His first time aboard, long ago, not even the maze of access tunnels had existed. Louis imagined ARM engineers, and after them Kzinti, ferreting out sham apparatuses one laboriously traced photonic circuit at a time.

As mired in molasses as his thoughts seemed, a few insights remained from his brief time as a protector. Never the reasoning, but sometimes the conclusions.

He found an intercom control. “Hindmost?” No answer. “Hindmost!”

“What?” the answer finally came.

“The lifeboat Tunesmith had in his workspace. The lifeboat we stowed aboard this ship just before leaving the Ringworld. It was on Long Shot in the first place, wasn’t it?”

“What do you mean?”

What did he mean? Tanj this dim-witted breeder brain!

Something glimpsed on the Ringworld, Louis thought. Something seen in the war room Tunesmith had improvised within the Ringworld Meteor Defense Room.

Or was it something not seen? Louis remembered the war-room display tagging a few ships with an icon to denote an indestructible General Products hull. This ship. Three ships that hung far back, remote from the Fringe War action. They, like Long Shot, had number four hulls. Puppeteer craft, he had thought then. Had he seen any smaller ships in a GP hull?

Louis said, “The lifeboat is built in a General Products #2 hull. The simplest explanation for such a lifeboat is that it was aboard the whole time.”

“Tunesmith may have captured it,” Hindmost said.

“While the Fringe War raged, while warships blasted holes in the Ringworld with antimatter, Tunesmith was clearing space aboard Long Shot to accommodate a ship a hundred meters long. I don’t think so.”

“Perhaps Patriarchy engineers installed the lifeboat.”

“Long Shot is all but defenseless. If Kzinti had had the option, instead of a lifeboat we’d have found a hangar jammed with fighter ships or something just as lethal.”

“Very well, Louis,” Hindmost said. “You have me. A lifeboat was always aboard. When Nessus sought you out for the Ringworld expedition. Even when Beowulf Shaeffer took this ship to see the galactic core.

“The Type II drive was new and experimental. Suppose it had stopped working far from Hearth, far from Known Space, beyond hope of rescue by conventional hyperdrive, beyond hope of the Outsiders rendering assistance. Then directions would have been hyperwaved to the pilot how he might release the lifeboat and perhaps, over a very long time, hope to return home.”

That answer Louis believed. “Thank you for not taking the lifeboat and abandoning me.”

“I brought you to the Ringworld against your will. If I can, I will take you safely away. Certainly I owe you that.

“If I have satisfied your curiosity for a while, may I hope you will permit me to continue my observations?”

*   *   *

STARING OUT THE MAIN BRIDGE view port at the stars, Hindmost let his mind wander. Invisible to the naked eye but (courtesy of Voice) prominent in an augmented-reality view was the endless swirl and shift of the ships of the Fringe War.

There was another dance to be seen, if he was not more devoid than usual of reason. At least he thought he saw a dance. Whenever Louis, still bursting with energy from the autodoc, ranging all about the ship, managed to leave him in peace.

From time to time Hindmost drank from a bulb of water. About the time it registered that the bulb seemed bottomless, he realized it must have been replaced. By Louis, on any of his several returns to the bridge.

Hindmost activated the intercom. “Thank you, Louis.”

“For what?”

“Indulging me. I am ready when you are.”

Louis soon appeared in the hatchway to the bridge. “What, exactly, do you see out there?”

As much as see, I hear. I feel. But perhaps it is only wishful thinking. “We will do a test, and then I will explain.”

Louis shrugged.

“Voice, run a correlation.” Hindmost sang out the cadence he had found—or imagined—in the display. “Across the Fringe War, how many ships leap about following that cadence?”

“Hold on,” Louis said. “How can it answer that?” Pause. “Hindmost’s Voice, can you tell ships apart?”

“To an extent,” Voice said. “The shadow-square sensors often catch the silhouettes of ships. By triangulation, I can determine distance, from which I calculate sizes. And I can distinguish hull compositions.”

“Hull compositions,” Louis repeated skeptically. “By spectral analyses?”

“Only rarely. In most cases the reflected light is too dim for that,” Hindmost said. “But among our sensor upgrades is something new. It appears that hull surface subtly influences the normal-space bubble that protects a ship from hyperspace. Those hints about hull material get imprinted onto the ripples made when ships enter and leave normal space.”

“That doesn’t sound possible,” Louis said.

“Hyperwave interacts with radio gear to perform hyperwave communications. These new sensors are little different, in principle.”

“In principle.” Louis laughed. “So we again have Tunesmith to thank.”

Hindmost shivered. “I am glad to be rid of protectors.”

“Back to identifying a particular ship for this correlation,” Louis said. “Among the larger formations, there must be many ships of a given type.”

“That is problematical,” Voice agreed. “When similar ships set out together and part ways in hyperspace, I cannot know which vessel went where.”

“Voice will tell us if he cannot do the correlation,” Hindmost said. As he will, because this may be the craziest idea I’ve had since … coming to the Ringworld.

“I have done the correlation,” Voice said. “While we spoke.”

Hindmost hesitated to ask. Suppose a correlation did exist. Would he dare to act on it? Hope and intuition struggled with innate caution.

“And?” Louis prompted.

“I find a correlation,” Voice said. “One ship.”

Louis blinked. “How did you know?” he asked Hindmost. “What was that pattern?”

“It is from a favorite performance of the Grand Ballet on Hearth. From a day I shared with someone very important to me.”

“Nessus?” Louis guessed.

“As you say.” Hindmost shivered, for how could Nessus be here? He had left Nessus on New Terra, the world that had for so long been their home. “Of course many know that ballet.”

“Is the dancing ship from the Fleet?” Louis asked.

“Doubtful,” Voice said. “It does not have a General Products hull.”

“You can be sure of that?”

“That it is not a General Products hull? That, Louis, I can say for certain. This one ship interacts with hyperwave quite differently from the obvious Fleet vessels.”

“Anything more?” Hindmost asked.

“Possibly. With so many hyperdrive emergences in this region I am uncertain. I first noticed that particular hull material only a day ago.”

“A new ship type,” Louis said. “An appearance two months after the Ringworld disappeared. It sounds like some new player came to see what’s happening here.”

Hindmost’s mind raced. After many years away, he could not know exactly where New Terra had traveled. Most likely, a New Terran ship could have reached here by now. It could be Nessus aboard that ship.

Assume for the moment that the new arrival had come from New Terra. Maybe, Hindmost thought, he could establish New Terran provenance another way. “Of what material is that new ship constructed?”

“I cannot tell,” Voice answered. “Our instruments sense differences among hulls, but they have not been calibrated to identify specific materials from hyperwave interactions.”

“And if we get a little closer? Perhaps, a light-hour?” Hindmost persisted. “Could you then remotely identify the hull material by spectral analysis?”

“Belay that,” Louis said. “Hindmost, I don’t understand. How does knowing the hull material tell you who is aboard?”

“Trust me that it might.” If the hull is of a particular material. The explanation would tread too close to secrets long kept from Louis. “Voice. How close?”

“Not where the ship is now,” Voice said. “Nearer the star, with brighter light, then yes.”

“Does the music in your head say where that ship will go next?” Louis asked.

Hindmost considered. The endpoints of jumps had not caught his eye, only the timing. Was he missing a vital clue? But no: the ballet was performed on a stage, the dancers’ graceful leaps circumscribed by gravity. The ship that he watched so hopefully darted about in three dimensions. “No. Only when.

“Keep watch on that ship,” Hindmost added to the AI. “Tell me when it is near enough to the star for spectral analysis from a light-hour away, and when Long Shot could approach it with no other ship any closer.”

“Approaching an unknown ship? That seems very brave of you,” Louis said.

Hindmost turned both heads to stare. “There is no reason to be insulting.”

*   *   *

HINDMOST HAD BEEN STUDYING bridge displays for hours. His eyes ached. His thoughts grew fuzzy. He needed sleep.

He sang aloud the next several bars of the libretto that echoed in his brain, ordering Voice to watch for the mystery ship’s next moves.

Louis wandered past the bridge yet again.

Hindmost closed his eyes but sleep refused to come. Fuzzy or not, his thoughts kept churning. Dancers. Ships. Leaps. Danger all around. Leaps. Partway home (well, Home, in any event), and back.

His eyes flew open. Louis had flown Long Shot much farther than he had allowed Voice to take it. “Voice, were internal instruments active during the hyperspace move toward Home?”

“They were.”

“Bring up the data.”

Displays lit on an arc running halfway around the bridge. Necks craning, Hindmost took it in, now and again reaching out to scroll deeper into the recordings. On other monitors, he reviewed data gleaned from studies of the Ringworld’s disappearance.

Patterns in the data reminded him of something, but for the longest time he could not put his tongue on it. An odd coincidence, he decided. He had seen such patterns before.

Long ago he had tried to reverse engineer the planetary drives purchased from the Outsiders. It was a desperate undertaking, to be sure—moving worlds involved vast energies—but not quite as insane as getting overrun by the genocidal Pak. Instead of discovering how the planetary drive worked, he had succeeded only in learning the many ways in which it might destabilize—

And that the energies so unleashed could vaporize a world.

Of course, very different mechanisms sometimes shared a mathematical description, as with pendulums and electronic oscillators. This parallelism surely meant nothing. Still, sometimes having an analogy suggested new ways to approach a problem …

Sipping from a drink bulb, his exhaustion forgotten, he thought how, while in office, he had opposed—to the modest extent Ol’t’ro tolerated opposition—the unending study of this ship. He thought how his newfound obsession with understanding the Type II drive would amuse Ol’t’ro. He thought about—

He straightened on the uncomfortable crash couch. His eyes closed, this time in concentration. For all the Ministry’s years of study, he had something they did not: protector-built instruments. And now he knew something they did not.

How to toggle the Type II drive to and from Type I speed.

The new hyperspace physics with which he dabbled remained incomplete, and yet—with Tunesmith’s help—he had made more progress in days than Ol’t’ro and the Ministry of Science together had in more than a century. Chords of triumph rose in his throats. Maybe he could barter for the Concordance’s freedom. This was his greatest insight since—

Reality crashed down. His greatest accomplishment since discovering how to destroy General Products hulls from a distance, without antimatter.

Long Shot had been built well before hulls were redesigned against such attacks.

Louis squeezed onto the bridge. “Did I hear you say something?”

“I was talking to myself,” Hindmost said. Because this time, I will understand the implications of my discoveries before I unleash them onto an unsuspecting galaxy.