They picked their way over the wasteground towards the heart of the maze, towards the Construct Council’s lair.

“Nothing.” Bentham Rudgutter clenched his fists on his desk.

“Two nights we’ve had the airships up and searching. Nothing at all. Another crop of bodies every morning, and not a godsdamn thing all night. Rescue dead, no sign of Grimnebulin, no sign of Blueday…” He raised bloodshot eyes and looked across the table at Stem-Fulcher, who sucked gently at the pungent smoke of her pipe. “This is not going well,” he concluded.

Stem-Fulcher nodded slowly. She considered.

“Two things,” she said slowly. “It’s clear that what we need is specially trained troops. I told you about Motley’s officers.” Rudgutter nodded. He rubbed and rubbed at his eyes. “We can easily match those. We could easily tell the punishment factories to run us off a squadron of specialist Remade, with mirrors and backwards weapons and all, but what we need is time. We need to train them up. That’s three, four months at the least. And while we’re biding our time the slake-moths are just going to keep picking off citizens. Getting stronger.

“So we have to think about strategies for keeping the city under control. A curfew, for example. We know the moths can get into houses, but there’s no doubt that most of the victims are picked off the streets.

“Then we need to dampen speculation in the press about what’s going on. Barbile wasn’t the only scientist working on that project. We need to be able to stamp out any dangerous kind of sedition, we need to detain all the other scientists involved.

“And with half the militia engaged in slake-moth duties, we can’t risk another dock strike, or anything similar. It could cripple us quickly. We owe it to the city to put an end to any unreasonable demands. Basically, Mayor, this is a crisis bigger than any since the Pirate Wars. I think it’s time to declare a state of emergency. We need extraordinary powers.

“We need martial law.”

Rudgutter pursed his lips mildly, and considered.

“Grimnebulin,” said the avatar. The Council itself remained hidden. It did not sit up. It was indistinguishable from the mountains of filth and garbage around it.

The cable that entered the avatar’s head emerged from the floor of metal shavings and stone debris. The avatar stank. His skin was patched with mould.

“Grimnebulin,” he repeated in his uncomfortable, wavering voice. “You did not return. The crisis engine you left with me is incomplete. Where are the Is that went with you to the Glasshouse? The slake-moths flew again last night. Did you fail?”

Isaac held his hands up to slow the questioning.

“Stop,” he said peremptorily. “I’ll explain.”

Isaac knew that it was misleading to think of the Construct Council having emotions. As he told the avatar the story of that appalling night in the cactus Glasshouse-that night of so-partial victory at such horrendous price-he knew that it was not anger or sadness that caused the man’s body to shake, his face to spasm in random grotesqueries.

The Construct Council had sentience, but no feelings. It was assimilating new data, that was all. It was calculating possibilities.

He told it that the monkey-constructs had been destroyed and the avatar’s body spasmed particularly sharply, as the information flooded back down the cable into the hidden analytical engines of the Council. Without those constructs, it could not download the experience. It relied on Isaac’s reports.

As once before, Isaac thought he glimpsed a human figure fleeting in the rubbish around him, but the apparition was gone in an instant.

Isaac told the Council of the Weaver’s intervention, and then, finally, began to explain his plan. The Council, of course, was quick to understand.

The avatar began to nod. Isaac thought he could feel infinitesimal movements in the ground under him, as the Council itself began to shift.

“Do you understand what I need from you?” said Isaac.

“Of course,” replied the Construct Council in the avatar’s reedy quaver. “And I will be linked directly to the crisis engine?”

“Yes,” said Isaac. “That’s how this is going to work. I forgot some of the components of the crisis engine when I left it with you, which is why it wasn’t complete. But that’s just as well, because when I saw them, they gave me the idea for all this. But listen: I need your help. If this is going to work we need the maths to be exact. I brought my analytical engine with me from the laboratory, but it’s hardly a top-notch model. You, Council, are a network of damn sophisticated calculating engines…right? I need you to do some sums for me. Work out some functions, print up some programme cards. And I need them perfect. To an infinitesimal degree of error. All right?”

“Show me,” said the avatar.

Isaac pulled out two sheets of paper. He walked over to the avatar, holding them out. In the dump’s smell of oil and chymical mould and warming metal, the organic stink of the avatar’s slowly collapsing body was shocking. Isaac creased his nose in disgust. But he steeled himself and stood beside the rotting, half-alive carcass and explained the functions he had outlined.

“This page here is several equations I can’t get the answers to. Can you read them? They’re to do with the mathematical modelling of mental activity. This second page is more tricky. This is the set of programme cards I need. I’ve tried to lay out each function as exactly as I can. So here for example…” Isaac’s stubby finger moved along a line of complicated logic symbols. “This is ‘find data from input one; now model data.’ Then here we have the same demand for input two…and this really complex one here: ‘compare prime data.’ Then over here are the constructive, remodelling functions.

“Is that all comprehensible?” he said, stepping back. “And can you do it?”

The avatar took the papers and scanned them carefully. The dead man’s eyes moved in a smooth left-right-left motion along the page. It was seamless until the avatar paused and shuddered as data welled along the cable to the Construct’s hidden brain.

There was a motionless moment, and then the avatar said: “This can all be done.”

Isaac nodded in curt triumph. “We need it…well…now. As soon as possible. I can wait. Can you do that?”

“I will try. And then as evening falls and the slake-moths return, you will turn on the power, and you will connect me. You will link me up to your crisis engine.”

Isaac nodded.

He fumbled in his pocket and drew out another piece of paper, which he handed to the avatar.

“That’s a list of everything we need,” he said. “It’s all bound to be in the dump somewhere, or it can be rigged up. Do you have some…uh…some little yous somewhere that can track this stuff down? Another couple of those helmets you got for us, the ones communicators use; a couple of batteries; a little generator; stuff like that. Again, we need that now. The main thing is we need cable. Thick conducting cable, stuff that can take elyctrical or thaumaturgic current. We need two and a half, three miles of the stuff. Not all in one, obviously…it can be in pieces, as long as they can be connected easily one to the next, but we need masses. We have to link you up with our…with our focus.” His voice quietened as he said this, and his face set. “The cable has to be ready this evening, by six o’clock I think.”

Isaac’s face was hard. He spoke in a monotone. He looked at the avatar carefully.

“There’s only four of us, and one of those we can’t rely on,” he went on. “Can you contact your…congregation?” The avatar nodded slowly, waiting for an explanation. “See, we need people to connect those cables across the city.” Isaac tugged the list out of the avatar’s hands and began to sketch on the back: a jagged sideways Y for the two rivers, little crosses for Griss Twist, The Crow, and scribbles delineating Brock Marsh and Spit Hearth in between. He linked the first two crosses with a quick slash of pencil. He looked up at the avatar. “You’re going to have to organize your congregation. Fast. We need them in place with the cable by six o’clock.”