“In no more than two minutes,” Saturn agreed. “But traffic is heavier now than when I clocked him before. I shall loap along the Bridge a-foot, and may out-pace him. Do you try to summon a hackney, or a sedan.” And he preceded Daniel out the door, and down stairs. Which was fortunate for Daniel, as several ink-spattered Main-Topp patrons had by now formed up at the base of the stairs, in a retaliatory mood. Their ardor cooled when Saturn sallied forth, and through the little Mobb broke a path that Daniel was not slow to follow. “Our work above is concluded,” Saturn announced, over his shoulder, as he went out, “and all losses shall be compensated anon-but not now.” And with that he burst out the front door of the Main-Topp and into the streaming crowd of the Bridge.

Saturn glanced left-towards Southwark and the Tatler-Lock-but turned right, anticipating that the buyer’s carriage would overtake him presently. By the time Daniel made it out the door, Saturn had already advanced several long strides in the direction of London. Daniel followed his example and glanced left-but it availed him nothing. He lacked both Peter Hoxton’s height, which would have enabled him to see over the crowd as far as the Great Stone Gate, and his youth, which made eyes quicker to adjust to the sudden brightness of the unroofed street.

All he had was a vague instruction to hire a coach or a sedan. No hackney of sound mind would await customers in front of the Main-Topp. Daniel guessed there might be chairs or coaches for hire in the Square, a short distance to the north. So he turned right, and began to thread his way through the jostling crowd.

Like the captain of a brittle ship hemmed in on all sides by massive ice-floes, Daniel could not make his own path, but had to move along with the general flow, and avail himself of any leads that snaked open before him before they drew shut and crushed his ribs. He made feeble progress compared to Saturn. Before he had progressed so far as the vault of the Chapel, he had lost sight of Saturn’s black head.

The artificial isles that supported the Bridge were called Starlings; the chutes between the Starlings, through which the divided River coursed, were denominated Locks. Daniel, unable to see much but heads and shoulders, estimated, by a kind of dead reckoning, that he must be passing over Long Entry Lock, which was the narrowest, hence most dangerous of them all, as the Chapel Pier to its north side had grown so fat over the centuries as to nearly pinch it shut. Then, looking up, he saw a stone vault overhead, and knew he was passing under the Chapel. Next (counting the Locks and Starlings in his head, like a Papist going through the Rosary) would be Chapel Lock-also quite narrow-but then St. Mary’s Lock, one of the widest on the whole bridge, hence, popular among watermen. Directly over St. Mary’s was the open fire-break called The Square. And it was there, Daniel reasoned, that hackney-drivers and sedan-porters would flock in hopes of swopping passengers with the watermen below.

Such was his plan. But as commonly happened to clever Natural Philosophers who have hatched elaborate schemes, he was overtaken by simple events. The crowd, hemmed in under the vault of the Chapel, suddenly pressed him from all sides. It was like being an atom of a gas in Boyle’s Rarefying Engine when the piston was slammed down by a terrific weight. A carriage was trying to force its way through-and succeeding. The crowd, sensing danger not so much from the carriage itself as from its bow-wave of panic, surged out from the dangerous confines of the vault, and Daniel, like a wine-cork tossed into Long Entry Lock, was spewed forth.

He was in the open now, tottering, looking about warily lest some eddy of the Mobb-rush take him unawares and crush him against a store-front. So he saw the carriage that had caused the trouble as it emerged from the vault, pressing on toward London.

He did not doubt that this was the one. Its window-curtains had all been drawn and its driver had evidently been paid to force his way to the other end of the Bridge with no concern for life, limb, or liability.

They were over Chapel Lock. The Square was only ten yards farther along-but this hackney had already passed Daniel by, and at its mad pace would soon overtake Saturn as well. Daniel still nursed some hope that he might be able to summon a carriage or a chair in the Square-but it would not be easy to persuade a strange driver to light out in hot pursuit of a hackney being driven as recklessly as this one. They needed to keep the buyer in sight as long as they possibly could; for there was no way of telling how long he would wait to put the key he had just paid for into the key-hole in the bottom of the chest, and turn it.

Daniel had, by default, staggered into the sudden open space left in the wake of the hackney. He was so close that he almost could have reached out and climbed aboard, if he’d been that spry. So he could hear-or so he phant’sied-a muffled pop from within, like a musket misfiring. Then flickering light shone through the curtains, and he heard from within a man shouting “Sacre bleu!”

Without being aware of how fast he was moving-for if anyone had asked, he’d have insisted he was too old to run-Daniel had followed the hackney right into the Square. The way widened slightly here. He saw Saturn standing to one side. He’d been conversing with a sedan-porter, but had broken off to stare at the buyer’s hackney.

Indeed many were now staring at it, for it was smoking. And it was making booms as the passenger flailed against the roof, signalling the driver to stop. The door on the right side flew open and disgorged a cloud of brown-gray smoke. So dense and voluminous was this, that a long and careful inspection was needed to see that there was a man in the middle of it. He was staggering away from the carriage, headed for the parapet that surrounded the Square to limit the number of pedestrians who toppled into St. Mary’s Lock. The passenger looked like a figure from Ovid: a Cloud metamorphosing into a Man. For the smoke had saturated the long hooded cloak that he wore, and was still billowing out of it. Gagging, he shuffled toward the parapet. The hackney-driver scrambled round to the open door, probed into the smoke with his whip-handle, and after a bit of scratching about, dragged out a blackened carapace: a burnt box, still sputtering and jetting a sturdy plume of thick yellowish smoke. Its lid was open to reveal a sheaf of pages, still legible though they’d been burnt to gray leaves of ash; these tumbled onto the pavement and Daniel, only a fathom away, saw the angular glyphs of the Real Character. But then he turned his attention back to the buyer, who had finally cast off his raiment of smoke, and stood at the parapet, feet spread wide, hands planted to support him as he retched into St. Mary’s Lock. Like a monk or wizard out of medieval times he looked in that robe. Then he was joined by a larger man who stepped in from the left and clapped his right hand on the other’s left shoulder.

The response of the hooded man was immediate-too quick for Daniel, who had a foreboding of what was about to happen, to shout a warning. The hooded man spun toward Saturn, pivoting around the shoulder that Saturn had gripped. Much was hidden by the robe and by smoke; but the movements of his shoulders told that he was driving his right hand toward Saturn’s belly.

But Peter Hoxton, by luck or by foresight, was ready for this. There had been something in the man’s stance at the parapet that had looked posed, and poised: perhaps it had roused in Saturn’s mind the same suspicions as in Daniel’s. Saturn got his left arm well inside of the other’s attack, and shouldered it aside. But then he jumped back. For as was now plain to everyone in the Square, the robed man was holding a small dagger in his hand. And as was clear to Daniel and to Saturn, the blade had been smeared with something.