Jack spent most of the ride home pondering what he’d seen. He noticed after a while that Enoch Root had been humming in a satisfied way, evidently pleased with himself for having been able to so thoroughly shut Jack up.

“So Alchemy has its uses,” Enoch said, noting that Jack was coming out of his reverie.

“You invented this?”

“I improved it. In the old days they used only quicksilver and salt. The piles were cold, and they had to sit for a year. But when dross of copper is added, they become warm, and complete the change in three or four weeks.”

“The cost of quicksilver is-?”

Enoch chuckled. “You sound like your lady friend.”

“That’s the first question she’s going to ask.”

“It varies. A good price for a hundredweight would be eighty.”

“Eighty of what?”

“Pieces of eight,” Enoch said.

“It’s important to specify.”

“Christendom’s but a corner of the world, Jack,” Enoch said. “Outside of it, pieces of eight are the universal currency.”

“All right-with a hundredweight of quicksilver, you can make how much silver?”

“Depending on the quality of the ore, about a hundred Spanish marks-and in answer to your next question, a Spanish mark of silver, at the standard level of fineness, is worth eight pieces of eight and six Royals…”

“APIECE OF EIGHT HAS eight reals- ” Eliza said, later, having spent the last two hours sitting perfectly motionless while Jack paced, leaped, and cavorted about her bedchamber relating all of these events with only modest improvements.

“I know that-that’s why it’s called a piece of eight,” Jack said testily, standing barefoot on the sack of straw that was Eliza’s bed, where he had been demonstrating the way the workers mixed the amalgam with their feet.

“Eight pieces of eight plus six royals, makes seventy royals. A hundred marks of silver, then, is worth seven thousand royals… or… eight hundred seventy-five pieces of eight. And the price of the quicksilver needed is-again?”

“Eighty pieces of eight, or thereabouts, would be a good price.”

“So-those who’d make money need silver, and those who’d make silver need quicksilver-and a piece of eight’s worth of quicksilver, put to the right uses, produces enough silver to mint ten pieces of eight.”

“And you can re-use it, as they are careful to do,” Jack said. “You have forgotten a few other necessaries, by the way-such as a silver mine. Mountains of coal and salt. Armies of workers.”

“All gettable,” Eliza said flatly. “Didn’t you understand what Enoch was telling you?”

“Don’t say it!-don’t tell me-just wait!” Jack said, and went over to the arrow-slit to peer up at the Doctor’s windmill, and down at his ox-carts parked along the edge of the stable-yard. Up and down being the only two possibilities when peering through an arrow-slit. “The Doctor provides quicksilver to the mines whose masters do what the Doctor wants.”

“So,” Eliza said, “the Doctor has-what?”

“Power,” Jack finally said after a few wrong guesses.

“Because he has-what?”

“Quicksilver.”

“So that’s the answer-we go to Amsterdam and buy quicksilver.”

“A splendid plan-if only we had money to buy it with. ”

“Poh! We’ll just use someone else’s money,” Eliza said, flicking something off the backs of her fingernails.

NOW, STARING DOWN THIS CROWDEDcanal towards the city, Jack saw, in his mind, a map he’d viewed in Hanover. Sophie and Ernst August had inherited their library, not to mention librarian (i.e., the Doctor), when Ernst August’s Papist brother-evidently, something of a black sheep-had had the good grace to die young without heirs. This fellow must have been more interested in books than wenches, because his library had (according to the Doctor) been one of the largest in Germany at the time of his demise five years ago, and had only gotten bigger since then. There was no place to put it all, and so it only kept getting shifted from one stable to another. Ernst August apparently spent all of his time either fending off King Louis along the Rhine, or else popping down to Venice to pick up fresh mistresses, and never got round to constructing a permanent building for the collection.

In any event, Jack and Eliza had paused in Hanover for a few days on their journey west, and the Doctor had allowed them to sleep in one of the numerous out-buildings where parts of the library were stored. There had been many books, useless to Jack, but also quite a few extraordinary maps. He had made it his business to memorize these, or at least the parts that were finished. Remote islands and continents splayed on the parchment like stomped brains, the interiors blank, the coastlines trailing off into nowhere and simply ending in mid-ocean because no one had ever sailed farther than that, and the boasts and phant’sies of seafarers disagreed.

One of those maps had been of trade-routes: straight lines joining city to city. Jack could not read the labels. He could identify London and a few other cities by their positions, and Eliza helped him read the names of the others. But one city had no label, and its position along the Dutch coast was impossible to read: so many lines had converged on it that the city itself, and its whole vicinity, were a prickly ink-lake, a black sun. The next time they’d seen the Doctor, Jack had triumphantly pointed out to him that his map was defective. The arch-Librarian had merely shrugged.

“The Jews don’t even bother to give it a name,” the Doctor had said. “In their language they just call it mokum, which means ‘the place.’ ”

From desire, ariseth the thought of some means we have seen produce the like of that which we aim at; and from the thought of that, the thought of means to that mean; and so continually, till we come to some beginning within our own power.

-HOBBES,Leviathan

AS THEY CAME CLOSERto The Place, there were many peculiar things to look at: barges full of water (fresh drinking-water for the city), other barges laden with peat, large flat areas infested with salt-diggers. But Jack could only gawk at these things a certain number of hours of the day. The rest of the time he gawked at Eliza.

Eliza, up on Turk’s back, was staring at her left hand so fixedly that Jack feared she had found a patch of leprosy, or something, on it. But she was moving her lips, too. She held up her right hand to make Jack be still. Finally she held up the left. It was pink and perfect, but contorted into a strange habit, the long finger folded down, the thumb and pinky restraining each other so that only Index and Ring stood out.

“You look like a Priestess of some new sect, blessing or cursing me.”

“D” was all she said.

“Ah, yes, Dr. John Dee, the famed alchemist and mountebank? I was thinking that with some of Enoch’s parlor tricks, we could fleece a few bored merchants’ wives…”

“The letter D,” she said firmly. “Number four in the alphabet. Four is this,” holding up that versatile left again, with only the long finger folded down.

“Yes, I can see you’re holding up four fingers…”

“No-these digits are binary. The pinky tells ones, the ring finger twos, the long finger fours, the index eights, the thumb sixteens. So when the long finger only is folded down, it means four, which means D.”

“But you had the thumb and pinky folded down also, just now…”

“The Doctor also taught me to encipher these by adding another number-seventeen in this case,” Eliza said, displaying her right with the thumb and pinky tip-to-tip. Putting her hand back as it had been, she announced, “Twenty-one, which means, in the English alphabet, U.”