“A bit like eBay.”

“Like that, yes.”

“Plenty of scope for bullying.”

“But that’s antisocial, too, and there are always plenty of people who would mark the bully down accordingly. It works. It is homeostatic — actually another example of feedback. But this time it’s negative feedback that tends to make a system stable, rather than drive it out of control.” He talked on, describing the Slan(t)ers’ projects.

I felt awkward. This was the kind of conversation we’d had as kids at school, or later as booze-fueled students: excitable, complex, full of ideas, the more outlandish the better. Peter had always been good at that, because he’d learned to be. Whereas other fat kids, it’s said, get a break from bullying by being funny, Peter’s defense was to have wilder ideas than anybody else. But now it wasn’t the same. We weren’t kids anymore.

And there was something else I couldn’t quite read in the way he spoke, this big, clumsy man with folded hands and his habit of adjusting invisible spectacles, talking earnestly. I had the impression of shadows, ranked behind him in the electronic dark, as if Peter was just a front for a whole network of densely interconnected, like-minded obsessives, all working for ends I didn’t understand.

Anyhow Slan(t) sounded like one giant computer game to me. “Interesting.”

“You don’t really think so,” he said. “But that’s okay.”

“But now,” I said, “perhaps we do see the aliens, in the Kuiper Anomaly. Isn’t that what you’ve been saying on TV?”

“That’s obviously a gross signature of something out there. Yes, it’s exciting.” His face was closed. “But I have a feeling that the origin of the Anomaly is going to turn out to be stranger than we think. And besides, it’s not the only bit of evidence we have.”

“It isn’t?”

“Perhaps there are traces out there, if you know how to look. Traces of life, of other minds at work. But they’re fragmentary, difficult for us to recognize and interpret. But I, well, as I told you I have this facility for pattern matching.”

I looked into my coffee cup, wondering how I could get out of the conversation politely.

But he had rotated his chair until he faced the desktop, and was briskly working a mouse. Images flickered over the screen. He settled on a star field — obviously color-enhanced — the stars were yellow, crimson, blue, against a purple-black background. Around a central orange-white pinpoint were two concentric rings, like smoke rings. The inner one was quite fine, but the outer, perhaps four times its diameter, was fatter, brighter. Both the rings were off-center, and ragged, lumpy, broken.

I searched for something to say. “It looks like a Fireball XL-Five end credit.”

Sometimes he lacked humor. “ Fireball was in black and white.”

“Tell me what I’m seeing, Peter.”

“It’s the center of the Galaxy,” he said. “Twenty-five thousand light-years away. A reconstruction, of course, from infrared, X-ray, gamma ray, radio images, and the like; the light from the center doesn’t reach us because of dust clouds. The sun is one of four hundred billion stars, stuck out in a small spiral arm — you know the Galaxy is a spiral. At the core, everything is much more crowded. And everything is big and bright. It’s Texas in there.” He pointed at the image. “Some of these ’stars’ are actually clusters. These rings are clouds of gas and dust; the outer one is maybe a hundred light-years across.”

“And the bright object at the center—”

“Another star cluster. Very dense. It’s thought there is a black hole in there, with the mass of a million suns.”

“I don’t see any aliens.”

He traced out the rings. “These rings are expanding. Hundreds of miles a second. And the less structured clouds are hot, turbulent. It’s thought that the big rings are debris from massive explosions in the core. There was a giant bang about a million years ago. The most recent eruption seems to have been twenty- seven thousand years ago. The light took twenty-five thousand years to get here — it arrived about two thousand years ago; the Romans might have seen something … If you look wider you can see the debris of more explosions, reaching much deeper back in time, some of them still more immense.”

“Explosions?”

“Nobody knows what causes them. Stars are simple objects, George, physically speaking. So are galaxies, even. Much simpler than bacteria, say. There really shouldn’t be such mysteries. I think it’s possible we’re seeing intelligence there — or rather stupidity.”

I laughed, but it was a laugh of wonder at the audacity of the idea. “The Galaxy center as a war zone?”

He didn’t laugh. “Why not?”

I felt chilled, but I had no clear idea why. “And how does Kuiper fit into this?”

“Well, I’ve no idea. Not yet.” He pulled up an image of his own face on CNN. “I’m hoping that if I can tap into the interest in Kuiper, I’ll get resources to push some of these questions farther. For instance, there may be links between the core explosions and Earth’s past.”

“Links?”

“Possibly the explosions tie in with extinction events, for instance.”

“I thought an asteroid impact killed off the dinosaurs.”

“That was a one-off. There have been eighteen other events. You can see it in the fossil record. Eighteen that we know of …”

I lifted my mug to my lips, but found it drained of coffee. I put the mug on the computer table and stood. “I ought to start my day.”

He looked at me doubtfully. “I’ve gone on too long. I’m sorry; I don’t get much chance to talk; most people wouldn’t listen at all … You think I’m a crank.”

“Not at all.”

“Of course you do.” He stood, looming over me, and grinned. Again there was that disarming self-

deprecation, and I sensed, uncomfortable again, that he really was glad to have renewed his connection with me, regardless of my reaction. “Maybe I am a crank. But that doesn’t mean the questions aren’t valid. Anyhow, you’re the one with the abducted sister.”

“That’s true. I ought to go.”

“Come back and tell me what you find.”

Magnus sat cross-legged, hunched over the little wooden game board.

Magnus was a great bear of a man with a head the size of a pumpkin, it seemed to Regina, a head so big his helmet seemed to perch on top of it. But then, his helmet wasn’t actually his but had been passed on to him from another soldier, just as had his sword and shield. Meanwhile his cowhide boots and his woolen tunic and his cucullus, his heavy hooded cloak, had all been made in the village behind the Wall, nothing to do with military issue at all. That awkward secondhand helmet had a dent in it, big enough to have held a goose’s egg. Regina wondered sometimes if the mighty blow that had inflicted the hollow had been the cause of the original owner’s “retirement.”

For all his bulk Magnus was a patient man, which was why Aetius approved of him as a companion for Regina. After five years on the Wall she thought she knew her way around, but some of the rougher soldiers, she had been told in no uncertain terms, were not suitable companions for the prefect’s twelve- year-old granddaughter.

Magnus was a good man, then. But he was so slow. His great ham of a hand hovered briefly over the board, but then he withdrew it.

“Oh, Magnus, come on,” Regina pleaded. “What’s so difficult ? It’s only a game of soldiers, and we’ve barely started. The position’s simple.”

“We haven’t all got a prefect’s blood in our veins, miss,” he murmured laconically. He settled himself more comfortably, his spear cradled against his chest, and resumed his patient inspection of the board.

“Well, my backside is getting cold,” she said. She jumped to her feet and began to pace up and down along the little tiled ridge behind the battlements.