The ferryman’s hefty Africans pace short reciprocating arcs on the deck, sweeping and shoveling the black water of the Charles Basin with long stanchion-mounted oars, minting systems of vortices that fall to aft, flailing about one another, tracing out fading and flattening conic sections that Sir Isaac could probably work out in his head. The Hypothesis of Vortices is pressed with many difficulties. The sky’s a matted reticule of taut jute and spokeshaved tree-trunks. Gusts make the anchored ships start and jostle like nervous horses hearing distant guns. Irregular waves slap curiously at the lapping clinkers of their hulls, which are infested with barefoot jacks paying pitch and oakum into troublesome seams. The ships appear to glide this way and that as the ferry’s movement plays with the parallax. Enoch, who has the good fortune to be a bit taller than most of the other passengers, hands the reins to Ben and excuses his way around the ferry’s deck trying to read the names.

He knows the ship he’s looking for, though, simply by recognizing the carved Lady mounted below the bowsprit: a gray-eyed woman in a gilded helmet, braving the North Atlantic seas with a snaky shield and nipples understandably erect. Minerva hasn’t weighed anchor yet-that’s lucky-but she is heavy-laden and gives every appearance of being just about to put to sea. Men are walking aboard hugging baskets of loaves so fresh they’re steaming. Enoch turns back toward the shore to read the level of the tide from a barnacled pile, then turns the other way to check the phase and altitude of the moon. Tide will be going out soon, and Minerva will probably want to ride it. Enoch finally spies van Hoek standing on the foredeck, doing some paperwork on the top of a barrel, and through some kind of action-at-a-distance wills him to look up and notice him, down on the ferry.

Van Hoek looks his way and stiffens.

Enoch makes no outward sign, but stares him in the eye long enough to give him second thoughts about pushing for a hasty departure.

A colonist in a black hat is attempting to make friends with one of the Africans, who doesn’t speak much English-but this is no hindrance, the white man has taught himself a few words of some African tongue. The slave is very dark, and the arms of the King of Spain are branded into his left shoulder, and so he is probably Angolan. Life has been strange to him: abducted by Africans fiercer than he, chained up in a hole in Luanda, marked with a hot iron to indicate that duty had been paid on him, loaded onto a ship, and sent to a cold place full of pale men. After all of that, you’d think that nothing could possibly surprise him. But he’s astonished by whatever this Barker is telling him. The Barker’s punching at the air and becoming quite exercised, and not just because he is inarticulate. Assuming that he has been in touch with his brethren in London (and that is a very good assumption), he is probably telling the Angolan that he, and all of the other slaves, are perfectly justified in taking up arms and mounting a violent rebellion.

“Your mount is very fine. Did you bring him from Europe?”

“No, Ben. Borrowed him in New Amsterdam. New York, I mean.”

“Why’d you sail to New York if the man you seek’s in Boston?”

“The next America-bound ship from the Pool of London happened to be headed thither.”

“You’re in a terrible hurry, then!”

“I shall be in a terrible hurry to toss you over the side if you continue to draw such inferences.”

This quiets Ben, but only long enough for him to circle round and probe Enoch’s defenses from another quarter: “The owner of this horse must be a very dear friend of yours, to lend you such a mount.”

Enoch must now be a bit careful. The owner’s a gentleman of quality in New York. If Enoch claims his friendship, then proceeds to make a bloody hash of things in Boston, it could deal damage to the gentleman’s repute. “It is not so much that he is a friend. I’d never met him until I showed up at his door a few days ago.”

Ben can’t fathom it. “Then why’d he even admit you to his house? By your leave, sir, looking as you do, and armed. Why’d he lend you such a worthy stallion?”

“He let me in to his house because there was a riot underway, and I requested sanctuary.” Enoch gazes over at the Barker, then sidles closer to Ben. “Here is a wonder for you: When my ship reached New York, we were greeted by the spectacle of thousands of slaves-some Irish, the rest Angolan-running through the streets with pitchforks and firebrands. Lobsterbacks tromping after them in leapfrogging blocks, firing volleys. The white smoke of their muskets rose and mingled with the black smoke of burning warehouses to turn the sky into a blazing, spark-shot melting-pot, wondrous to look at but, as we supposed, unfit to support life. Our pilot had us stand a-loof until the tide forced his hand. We put in at a pier that seemed to be under the sway of the redcoats.

“Anyway,” Enoch continues-for his discourse is beginning to draw unwanted notice-“that’s how I got in the door. He lent me the horse because he and I are Fellows in the same Society, and I am here, in a way, to do an errand for that Society.”

“Is it a Society of Barkers, like?” asks Ben, stepping in close to whisper, and glancing at the one who’s proselytizing the slave. For by now Ben has taken note of Enoch’s various pistols and blades, and matched him with tales his folk have probably told him concerning that fell Sect during their halcyon days of Cathedral-sacking and King-killing.

“No, it is a society of philosophers,” Enoch says, before the boy’s phant’sies wax any wilder.

“Philosophers, sir!”

Enoch had supposed the boy should be disappointed. Instead he’s thrilled. So Enoch was correct: the boy’s dangerous.

“ NaturalPhilosophers. Not, mind you, the other sort-”

“Unnatural?”

“An apt coinage. Some would say it’s the unnatural philosophers that are to blame for Protestants fighting Protestants in England and Catholics everywhere else.”

“What, then, is a Natural Philosopher?”

“One who tries to prevent his ruminations from straying, by hewing to what can be observed, and proving things, when possible, by rules of logic.” This gets him nowhere with Ben. “Rather like a Judge in a Court, who insists on facts, and scorns rumor, hearsay, and appeals to sentiment. As when your own Judges finally went up to Salem and pointed out that the people there were going crazy.”

Ben nods. Good. “What is the name of your Clubb?”

“The Royal Society of London.”

“One day I shall be a Fellow of it, and a Judge of such things.”

“I shall nominate you the moment I get back, Ben.”

“Is it a part of your code that members must lend each other horses in time of need?”

“No, but it is a rule that they must pay dues-for which there is ever a need-and this chap had not paid his dues in many a year. Sir Isaac-who is the President of the Royal Society-looks with disfavor on such. I explained to the gentleman in New York why it was a Bad Idea to land on Sir Isaac’s Shit List-by your leave, by your leave-and he was so convinced by my arguments that he lent me his best riding-horse without further suasion.”

“He’s a beauty,” Ben says, and strokes the animal’s nose. The stallion mistrusted Ben at first for being small, darting, and smelling of long-dead beasts. Now he has accepted the boy as an animated hitching-post, capable of performing a few services such as nose-scratching and fly-shooing.

The ferryman is more amused than angry when he discovers a Barker conspiring with his slave, and shoos him away. The Barker identifies Enoch as fresh meat, and begins trying to catch his eye. Enoch moves away from him and pretends to study the approaching shore. The ferry is maneuvering around a raft of immense logs drifting out of the estuary, each marked with the King’s Arrow-going to build ships for the Navy.