“The one-armed Muscovite is no foreign agent,” Daniel prophesied, “but a sort of Phanatique who absconded from Russia for the same reason that my great-grandfather, John Waterhouse, fled to Geneva during the reign of Bloody Mary. At loose ends in London, he somehow became a part of Jack’s criminal net-work. I am quite certain he has not the slightest intention of going back to Russia.”

“Your hypothesis is belied by your own evidence,” Isaac said. He had reverted to a high, magnificent tone that he used for philosophical discourse. “You have convinced me that the same organization that set off the Crane Court explosion, burned the Tsar’s ship in Rotherhithe. But a mere band of criminals does not pursue foreign policy!”

“It may be that the Swedes paid them to destroy the ship a-building,” Daniel said, “which is easier than sinking it after it is launched and armed. Or it may be that the Muscovite, being, as I gad, a sort of Phanatique, did it by himself, as Puritans used to strike whatever blows they might against the King.”

Isaac reflected for a moment, then said, “To carry on discourse, of a speculative nature, about Jack’s organization and its designs, is idle.”

“Why is it idle?”

“Because in a few hours they will be in our power, and then we may simply ask them.”

“Ah,” Daniel said, “I could not tell if we were going to arrest Jack the Coiner, or invade France.”

Isaac briefly made a noise that sounded like laughing. “We are going to lay siege to a castle.”

“You can’t be serious.”

“ ’Tis a Jacobite stronghold,” Isaac said. He was being just a bit facetious.

“So in a sense we are going to invade France,” Daniel muttered.

“One might think of it as a chip of France on the banks of the Thames,” Isaac said, showing a taste for whimsy that was, to say the least, out of character. But (as shown by the laugh and the sarcasm) he’d learned a conversational gambit or two during his decades in London.

For example, prating about the genealogy of noble families: “You remember the Angleseys, I am certain.”

“How could I not?” Daniel answered.

Indeed, the very mention of the name forced him to come awake, as if he had had just been told that the sails of Blackbeard had been sighted on the horizon. He looked Isaac full in the face for the first time since the conversation had begun.

As a young man Daniel had known the Angleseys as a clan of dangerous crypto-Catholic court fops. The patriarch, Thomas More Anglesey, Duke of Gunfleet, had been a contemporary, and a mortal rival, of John Comstock, who was the Earl of Epsom and the first great noble backer of the Royal Society. Comstock had been the C, and Anglesey the first A, in the CABAL, the group of five who had run the Restoration government of Charles II.

In those days Daniel had been too naive to comprehend just how close the connections were between the Angleseys and the royal family. Later, he’d learned that the two sons of Thomas More Anglesey, Louis (the Earl of Upnor) and Phillip (Count Sheerness), were both bastards of Charles II, fathered on a French Countess during the Interregnum, when Charles had been exiled in France. Thomas More Anglesey had then been induced, somehow, to marry the embarrassed Countess and raise the two boys. He’d done a wretched job of it-perhaps he’d been distracted by ceaseless plot-making against John Comstock.

The younger of the two “Anglesey” bastards, Louis, had been a great swordsman, and had used Puritans as practice targets during his years at Trinity College, Cambridge. He’d been there at the same time as Daniel, Isaac, and various other fascinating human specimens, including Roger Comstock and the late Duke of Monmouth. Later, Louis had become interested in Alchemy. Daniel even now blamed him for seducing Isaac into the Esoteric Brotherhood. But there was no point in laying blame today-for the Earl of Upnor had perished a quarter-century ago at the Battle of Aughrim, fending off a hundred Puritans, Germans, Danes, amp;c. with his rapier, until shot in the back.

By that time his supposed father, the Duke of Gunfleet, had long since died. The Duke’s final years had not been good ones. Having ruined the Silver Comstocks-driven John into rustic retirement, and the rest of them all the way to Connecticut-and having taken over their house in St. James’s, he had seen his own fortunes destroyed, by bad investments, by his sons’ gambling debts (which must have hurt him all the more, as they weren’t really his sons), and above all by the Popish Plot, which was a sort of politico-religious rabies that had taken over London round 1678. He had packed the entire family off to France and sold the London palace to Roger Comstock, who had promptly leveled it with the ground and turned it into a real estate development. In France the Duke had died-Daniel had no idea when, but it would have been a long time ago-leaving only Phillip, Count Sheerness: the older of the two bastards.

Count Sheerness. All of these names-Gunfleet, Upnor, and Sheerness-referred to places round the mouth of the Thames, and had been handed out to the Angleseys by Charles II in reward for services performed at time of the Restoration. Daniel could only recollect a few of the details. Thomas More Anglesey had been in a wee naval scrap off Gunfleet Sands, and sunk a boat-load of die-hard Puritan sailors, or something like that, and had proceeded to the Buoy of the Nore, where he’d rallied a lot of Royalist ships around him.

The Nore was a sandbar-really the extremity of a vast region of shifting sands deposited round the place where the Thames and the Medway joined together and emptied into the sea. A Buoy had always been anchored there, a few miles off Sheerness Fort, to warn incoming ships, and to force them to choose between going to port-which would, God and tides willing, take them up the Medway, under the guns of Sheerness Fort and then of Castle Upnor, and eventually to Rochester and Chatham-or to starboard, which set them on the way up the Thames to London. Anglesey’s makeshift fleet had been neither the first nor the last invasion force to use that buoy as a rallying-point. The Dutch had done it a few years later. In fact, one of the peculiar duties assigned to the naval ships in this part of the river was to sail up to the Buoy and blow it out of the water whenever serious trouble loomed, so that foreign invaders could not find it.

At the time Charles II had come back, the ignominious Dutch invasion lay in the future, and Sheerness and Upnor seemed glorious names. But to any Englishman who’d been alive and awake during the Anglo-Dutch War, most certainly including Daniel and Isaac, such words as “Buoy of the Nore” and “Sheerness” connoted dark doings by foreigners, farcical bungling by Englishmen, grievous humiliation, proof of England’s vulnerability to seaborne intruders.

So if Isaac’s reference to Count Sheerness was the ink, then all of this history was the page the ink was printed on.

If they kept going as they were, they’d be in view of the Buoy of the Nore in a few hours.

“You can’t be serious,” Daniel blurted.

“If I observed faces, instead of stars, and philosophized about thinking, instead of Gravity, I could write a treatise about what I have seen passing over your visage in these past thirty seconds,” Isaac said.

“I wonder if I am arrogant to think that Waterhouses are no less deeply enmeshed in the affairs of the world, than Angleseys or Comstocks. For just when I think that all have passed on, and my connections to them severed-”

“You find yourself on a boat for Sheerness,” Isaac concluded.

“Tell me the tale, then,” Daniel said, “for I’ve not kept up with the Angleseys.”

“They’ve a French name now, and French titles, inherited from the mother of Louis and Phillip, and they dwell at Versailles, save when they are at the exile court in St.-Germain, paying homage to the Pretender. Only Phillip survived long enough to propagate the line-he had two sons before he was poisoned by his wife in 1700. The sons are in their twenties; neither has been to England or speaks a word of English. But the older of the two remains Lord of the Manor in certain pockets of land around Sheerness, on either bank of the Medway.”