"Yes. I was hoping to ask you about the Engine."

Gracewell looked somewhat rea.s.sured. "Hah," he said. "You want work? It'll be months before we can rebuild. Months. All in disarray."

"It was a sort of difference engine, wasn't it?"

The cab rattled down a street of red-brick houses, at the end of which a great traffic light stood idle and unlit.

"Yes," Gracewell conceded. "More or less. More precisely, no. But yes."

"With men instead of mechanical parts."

"Yes." Gracewell sighed. "More precisely in addition to."

He pulled out a handkerchief and dabbed at a cut on his lip. He gave Arthur a long look, and seemed to reach a decision. "Ahem. Hah. Now, a difference engine is a toy, Shaw-a mere adding machine. More precisely, it operates by repeated addition. Crank the handle, and it adds; that's all it does. Thus it can generate tables. Nothing you or I couldn't do, though less p.r.o.ne to distraction and error. Now! An a.n.a.lytical engine is a more interesting notion. A hundred variables, a thousand variables-a thinking machine of universal purpose, subject to instruction, capable of all of the functions of mathematics and logic. The equal in reasoning to a man. His superior for precision, reliability, and complexity of calculation. Moreover, men are expensive, unreliable, and nosy." He glared at Arthur, then dabbed fresh blood from his lip. "Ow. I think I've a tooth loose."

"Hmm," Arthur agreed, gently rubbing his swollen knuckles.

"Still, though man is inferior in some respects, there's more to life than mathematics, more to the mind than logic. No merely mechanical engine can ever perform all the functions of which a man is capable."

The driver shouted at someone in traffic.

"An engine," Gracewell said, "of which each critical variable is a man, who can therefore perform not only simple operations of addition and multiplication and division, but can also apply to his task the vital forces. The whole much greater than the sum of its parts, capable of resolving psychic operations too vast for one mind."

He paused dramatically.

"Babbage proposed a thinking machine. What I've made is a perceiving machine."

"It's a-some sort of an occult engine, then."

"A Vital Engine, if you must give it a name. This is science, Mr Shaw, the modern science. You look sceptical."

"And the headaches and-"

"Never enough men, that was the problem. Too many faltered. The Work made unusual demands on the spirit. Uncharted territory, calculating the revolutions of the spheres. It called for intuition, perception, what Atwood's lot call clairvoyance. So we recruited fortune-tellers, mediums, poets, that sort of person. At first, at least. When we ran out we found insurance clerks worked adequately. Atwood says the Sight can't be taught, but I believe that you can drum anything into a man's head if he's hungry enough."

"It was Mr Atwood who recommended me to you."

"Oh yes. I recall. Oh h.e.l.l!"

"Excuse me?"

"Loose. The tooth. No question."

They listened in silence to the noise of traffic for a while. "Why were we all barefoot?"

"Good G.o.d, Shaw, is that what you hunted me down to ask?"

"No. But I always wondered."

"Because," Gracewell sighed, "the variables were barefoot on one of the earliest successful tests. Coincidence? Probably. One never knows what might make the difference. It's so delicate, and we're under such time pressure. This is an entirely new science, Shaw."

"But what is it for?"

"I'm not at liberty to say. Suffice to say that it is of tremendous importance."

"May I guess? I've had a great deal of time to think, since the fire."

"I hardly see how I can stop you from guessing, Mr Shaw."

"Well, then-first, whatever you were doing, someone was paying for it, and paying a quite extraordinary amount of money. I don't doubt that whoever invested those sums expected a profit. Second, it involved numbers. Third, you maintained secrecy. Fourth, you have rivals who will stop at nothing to steal or stop your work. Fifth, you tell me that the work had to do with telepathy and clairvoyance-I don't know that I believe that, but I don't know that I don't, and at the very least I believe you believe it. Sixth, it made nothing physical. It seems to me that your work must have something to do with money itself-with speculation. What if you had built, or believed you had built, an engine that could predict and calculate risks-let's say, the weather; storms off the Cape of Good Hope, perhaps, or bad harvests in the Azores. Warehouse fires in Bradford. What'll the Bank of England do next, before the bankers themselves know. Now, that would make a fine profit, and would have to be kept quite secret-you could hardly make a profit on predictions if everyone knew of them. And suppose your backers are a consortium of financiers: those outside the circle would have reason to fear and oppose them. Am I on the right track?"

"Hmm," Gracewell said. "I can see why you throve in journalism."

They were stuck in traffic. There was new road being laid down somewhere; the smell of hot tarmacadam was overpowering.

"Blackfriars," Gracewell shouted.

Arthur said, "What's in Blackfriars?"

"Nothing. But by the time we've been there and back those men should be long gone."

"Who were those men?"

"I don't know. Pale fellows, weren't they? Bad habits, I expect."

A flick of the whip, and the cab was off again. Gracewell pulled a packet of tobacco from his pocket.

"You dropped your pipe," Arthur said. "I'm afraid I stepped on it."

"Oh, h.e.l.l. Well, I've answered your questions, as far as I intend to. What else do you want from me, Mr Shaw?"

"I saved you from those men, Mr Gracewell-I think you owe me more answers."

"I a.s.sure you, I was quite capable of defending myself." Gracewell put the tobacco back into his pocket, took out his watch, and started to wind it. "But that's not to say we don't need man-power. We're going to rebuild it, of course. The Engine."

"We? You, and Atwood, and the Europa Company?"

"Hmm? Oh. You saw that, did you? Where else have you been poking around, I wonder? Anyway, we shall rebuild. Again. I suppose you never saw the first Engine. We built it near the West India Docks. Underground, for the most part. For safety, we thought! b.l.o.o.d.y thing flooded, of course. In the storm. Next time, who knows what they might do? Bomb us, perhaps, like a lot of b.l.o.o.d.y whatchamacallems, nihilists. Hmmph. Anyway. So you've been reading about a.n.a.lytical engines, have you?"

"Yes. I read your monograph."

"Oh yes?"

"I read about your, ah, your vision of the Intelligences from M-"

Gracewell clacked the watch shut, and his mouth went tight. "That was a long time ago. I suffered at the time from exhaustion. I experienced a nervous collapse."

"But-"

"My son died in '84. He was a soldier. Africa. My wife, soon after. It upset me, Mr Shaw. I suffered visions."

Gracewell leaned forward and called directions to the driver. It was clear that he would say no more on that subject.

Arthur asked him if he knew who among the men of Room 13 had survived the fire.

"Don't know. Scattered all over London. Months of work wasted."

"Mr Vaz?"

"Who?"

"Dimmick?"

"Unwell. Sulking. Between you and me, I think he went a bit mad there, towards the end."

"He wasn't the only one, was he? I saw him drag men out of the rooms, screaming. Unusual demands on the spirit, you said. Why? What happened to them? What became of-"

"Listen, Shaw. They were well paid for the job and I owe no apology. Ours is a great enterprise and some must suffer for it. That's life, isn't it? Some must fall so that others may rise. Now: on that subject. Perhaps I can use you, Shaw. Not in the rooms. A higher calling."

The cab had stopped in traffic. The driver was making small talk about the weather with the driver of a donkey-cart.

"Do you box, Shaw?"

"At school."

"I thought so. Well, your education was not wasted."

He directed the driver to turn back towards St. Pancras.

"I need help, Shaw, and you, you have ambition. Now take this." He dropped the watch and chain into Arthur's hand.

"Mr Gracewell-"

"Payment for your a.s.sistance back there. I won't be indebted, you hear? Open it in the event that you run afoul of those thugs again; it will protect you. Now this squares us, do you understand? Open the watch in the event of danger. Not otherwise. Now, you're looking for work."

"For answers, Mr Gracewell."

Gracewell took an envelope out of his pocket. "I think you might work for nothing, if only I promised to pay you in secrets; isn't that right, Mr Shaw?

"Certainly not." He was rather afraid it might be.

"Hah. But, as it happens, money is nothing, and secrets are far more dear. I'll pay you-I don't know, let's say twenty pounds-to take this envelope to St. John's Wood."

He held out the envelope until Arthur took it from him.

Twenty pounds to take an envelope to St. John's Wood, and as if it were nothing! That was a kind of magic, as impressive to Arthur in its way as if Mr Gracewell had summoned up an imp, or turned water into wine.

The cab deposited them both outside St. Pancras. Gracewell entered the station.

Arthur set off walking towards St. John's Wood, through a bright spring afternoon. He went slowly, keeping an eye out. He watched for a.s.sailants who might jump from behind lamp-posts or out of alleyways, or pickpockets in the crowds and noise. He kept clear of the road, for fear that some thug in a cab might come rushing past, hand outstretched to s.n.a.t.c.h the precious envelope from him.

It was an ordinary white envelope, sealed. It was marked with an address on Charles Lane, and the word PRIVATE. Both were written in a firm square hand that resembled the way Gracewell wrote his instructions. Inside was a folded letter. Arthur couldn't read what was written on it, though he stopped and held it up to the light.

The watch was also quite ordinary. It was made of silver, rather tarnished, rather scuffed. On the back were the letters N.G. and the name of the manufacturer. Otherwise it was plain and smooth. The chain was also silver, and showed signs of mending. Arthur couldn't see the face without opening it, which Gracewell had ordered him not to do. He considered opening it anyway, to prove to himself that he didn't take Gracewell's absurd order seriously.

The address belonged to a little red-brick house, with a bra.s.s letter-box, and flower-pots in the window.

Arthur put the envelope half-way in through the box, then changed his mind. For twenty pounds, one should knock.

A tall grey-haired man answered, took the letter, tore it open, scowled, and said, "Gracewell. Tell him yes. d.a.m.n it, tell him yes." Then he closed the door.

Arthur took the bus back to St. Pancras. He walked to the offices of the Europa Company and rang the bell. A young clerk-not Dimmick, thank G.o.d!-opened the door, paid Arthur his twenty pounds, and told him that Mr Gracewell said to come back at noon tomorrow.

Over the following week Arthur carried letters to Aldwych, Bethnal Green, Bromley, Camden Town, Kilburn, Poplar, and Sh.o.r.editch (twice). Sometimes he took letters back. Undemanding work. Why Gracewell couldn't simply use the post-office like anyone else, Arthur didn't know. He supposed there was a great deal Gracewell wanted to keep secret from his rivals. Clearly he was conveying offers and counter-offers for the work of reconstructing the Engine-brick and lumber, iron and copper, labour and machines, electricity and licenses and contracts. Once the thing was running again there would no doubt be opportunity for advancement, for a man who'd earned Gracewell's confidence. There would no doubt be answers.

He visited carpenters, masons, and foremen at the docks, and lawyers at Lincoln's Inn. Each saw only a part of the operation; but Arthur began to see glimpses of the whole.

Josephine still didn't like the work. He supposed she was right. He didn't quite believe Gracewell's vague talk about unusual demands on the spirit, and clairvoyance, and so on, but there was unquestionably something sinister about the whole business. It was quite possible that something terrible had happened to poor Mr Vaz. He considered going to the police; but not yet, not until he knew what it was all about. He'd quit, he promised Josephine; soon, but not yet.

Chapter Twelve.

Josephine sat at her desk, staring at a white page, quite unable to bring herself to type a word of Mr Albert Potter's alchemical monograph. It was absurd, pure nonsense. It made her want to scream. It was also two weeks overdue, but she could think of very little else these days except for Gracewell, and Atwood, and whatever danger Arthur was getting himself into; and above all the stars, the heavens, the revolutions of the spheres, and that manifestation. Dreadfully pagan and outlandish things to think, shortly after lunch on a Wednesday, sitting in a bas.e.m.e.nt in Bloomsbury in front of a new-model Remington Standard Typewriter with a sticky R! She had to tell Arthur. She couldn't keep it all to herself very much longer, or she'd burst. Besides, he had to understand the danger he was in.

He said he was only taking messages, a sort of overpaid postman, an insignificant cog in Gracewell's new Engine. And perhaps that was true, but the nature of that engine was unearthly, sinister, unnatural. But how could she tell him? Blurt out, while they walked in the park, Did I mention that Lord Atwood and I-who, by the way, says h.e.l.lo-met a moon-man the other night? Bagged him, in fact, like a pheasant ... Perhaps she could mention the moon a lot in conversation, or mention the weather on Venus at dinner, and test his reaction. She was afraid he'd think she was mad, the way her mother had gone mad. And suppose he believed her; would he understand how strange and frightening the whole thing had been? Or would he go knocking on Atwood's door, eager to see it for himself?

How could she tell him; but how could she not?

Quite a lot of time seemed to have pa.s.sed while she sat and thought, and she had typed nothing but Atwood and then a little later the words moon-man.

She sighed, and stretched, then yelped in surprise. There was a man at the window, ash-pale face pressed against the gla.s.s. Two inky black eyes peered out from under a black bowler hat.

She'd seen that face before, she realised-or one very much like it-reflected in the mirror at Mrs Sedgley's house a few months ago, spying on Atwood.

She jumped up from her chair, grabbed the key from the hook by her desk, and darted for the door. She was too late; the man at the window had a companion, who opened the door in her face, pushed inside past her, and sat down in her chair, drumming grubby fingers on Mr Potter's ma.n.u.script.

The one who'd been waiting at the window ambled up and leaned in the doorway, hands in the pockets of a long grey coat.

Her heart pounded. She squeezed the key in her hand very tightly, finding it gave her a certain comfort.