Alastair Reynolds - Century Rain

“This is not good,” she said. “Don’t you have any clues? He only had one ship. Only one of those portals was really used.”

“That’s our only straw,” Tunguska said. “As it is, one of the portals shows a slightly different collapse signature compared to the other two he might have used. If I had to put money on it, I’d say that’s the one that really had a ship squeezed through it.”

“How much money?” she asked, smiling.

“You’d rather not know.”

“OK,” Auger said. “If that’s our only option… we have to take it. Once we’re inside, will we be able to bounce an echo off him?”

“Perhaps,” Tunguska said, “but the absence of an echo won’t necessarily prove that we chose the wrong door. He could be just too far ahead of us for it to reach him.”

“Do we have any other options?”

“No. That’s why I’ve already committed us to the portal with the odd signature. As soon as drive repair is complete, we’ll ramp up to maximum pursuit thrust.”

“Good,” Auger said. “I’d rather be chasing a shadow than sitting around here talking about it.”

“Unfortunately, chasing shadows may be all we end up doing. Even if that signature is real, it’s at the limit of readability. If Niagara had shaved just an additional hour off his arrival time, we’d never have seen it.”

“Then we’d better not waste a minute.”

“That’s the problem.” Tunguska replaced the schematic image of the quadruple-portal system with the fractured-glass map of the galactic hyperweb network. He zoomed in on one little area, highlighting a conjunction of four filaments. “This is where we are now,” he said. “And this—given our best guess—is where Niagara will emerge, after an eight-hour transit.”

He directed their attention to another part of the map, further around the great clockface of the galaxy.

“Another cluster of portals,” Auger said.

“Six, all told, including the one we’ll enter through. There’s no ALS there, so it can’t be his final destination. He’ll be taking another portal.”

“We’ll just have to hope that the same trick works twice.”

“It won’t, I’m afraid,” Tunguska said. “The time differential between his departure and our arrival will be too great. There’ll be no detectable difference between the portals, regardless of the fact that only one of them will have had a ship fly through it.”

“Meaning what?”

“Meaning that unless he has spectacular bad luck between here and there—we’ll have lost him.”

“We can’t lose him,” Auger said. “That’s simply not an acceptable outcome.”

“We may have to live with it. He knows the way to the ALS. We don’t. It’s that simple.”

“Cassandra should have looked at those documents in more detail,” Auger said, with an odd feeling of self-criticism, as if she was reproaching herself for some unacceptable omission or failing.

“She did the best she could,” Tunguska said. “At the time, she had only a vague idea that they might be of strategic importance. It’s lucky we got what we did.”

“Lucky?” Auger snapped. “The cargo told us nothing.”

“I’m sorry,” Tunguska said. “If there was anything I could do… We’ll continue the chase, of course, and hope for good luck.”

“That’s the best you can offer?”

“I’m afraid so.”

No one said anything, until Floyd raised his hand and spoke. “Anyone mind if I make a small contribution?”

The bleed-drive was still not ready for maximum thrust. While they toiled at a leisurely one gee towards the suspect portal, Floyd led Auger and Tunguska back to his quarters.

“This had better be worth it,” Auger said.

“You got any viable alternatives?”

“I just mean… don’t raise false expectations here, Floyd. I know you’re trying to help, but really.”

He looked back at her, wounded pride on his face. “ ‘But really’ what?”

“This is a very technical matter,” she said.

“What she’s saying,” Tunguska interjected, adopting a conciliatory tone, “is that there are some things you might be reasonably expected to have a useful opinion on… and some things you might be reasonably expected not to have a useful opinion on.”

“I see,” Floyd said tersely.

“And I’m afraid the matter of hyperweb navigation falls resoundingly into the latter category,” he went on.

“At least hear me out, Jack.”

“Floyd, I know you mean well,” Auger said, “but we really should be preparing for when the bleed-drive is back on-line.”

“Wouldn’t you like to know that you’re headed in the right direction, before you light that torch?”

He opened the door into the vast enclosure that served as his temporary quarters. The three of them walked towards the bed and its little entourage of attendant furniture.

“Floyd—give me a clue, will you?”

“It was something you said yourself, Auger: how the hell did they make sense of the numbers coming out of that antenna thing, if they had to do it in nineteen fifty-nine?”

“Enlighten me,” Auger said.

“And me, while you’re at it,” Tunguska said.

“We were looking for a microdot, or something like it,” Floyd said, “because we thought we were only looking for ten or twelve digits—the map reference of the ALS.”

“Go on,” Auger said, feeling a little shiver of excitement despite her misgivings.

“Well, we were dead wrong. I think.”

“Floyd—don’t drag this out.”

Floyd sat down on the bed and offered Tunguska and Auger the two remaining chairs. “Face it: it was always hopeless looking for something like that. You said it, Auger—the message could have been buried anywhere, in the tiniest smudge or the tiniest change in the position or weight of some printed characters. You’d have to know exactly what you were looking for in order to find it.”

“Floyd…” she said warningly.

“But that still leaves a big question unanswered: how did they come up with those numbers? It was one thing building that antenna, but making sense of what it was telling them—well, even you speculated that it would have been difficult, given the way things are in my nineteen fifty-nine.”

“Computers don’t exist in Floyd’s world,” Auger explained to Tunguska. “They are even further behind than our fifty-nine, since they never had the Second World War as a spur to drive computing progress.”

“I see,” Tunguska said, stroking his chin. “In which case, it’s difficult to see how the data from the gravitational wave device could ever have been processed. It would be a tricky little exercise even now.”

“Not too tricky, I hope,” Floyd said, “because I think you’re going to have to do it.”

“What have you found?” Tunguska asked.

Floyd reached into the box at the foot of the bed and pulled out one of the records inside it. Auger saw the label: Louis Armstrong.

“This,” he said simply.

“I had the distinct impression that you were a little under-whelmed with those discs,” Tunguska said.

“You were damned right.”

“And now?”

“I’m wondering if that wasn’t the clue we were looking for all along.” Floyd tipped the sleeve so that the grooved disc slid into his hand. “I think the information you’re looking for is here,” he said.

“In a microdot on the label?” Auger asked, still puzzled.

“No. Something more complex than that. I think it could be in the music itself. Not just ten or twelve digits, but the actual numbers from the antenna. You were right, Auger: there was no way to interpret the data in nineteen fifty-nine. So they didn’t even try.”