“But how is an ordinary investor to match your level of confidence, Dr. Waterhouse?”

“By looking at that,” Daniel answered, nodding at St. Paul’s, “and noting that it does not fall down. Go and examine its arches, Mr. Threader, and you will see that they are in the shape of parabolas. Sir Christopher Wren made them thus, on the advice of Hooke; for Hooke shewed that it should be so.”

“You have quite wandered away from me. It is an excellent church. I see no connection to steam-engines.”

“Both church-domes and engines are subject to physical laws, which are, in turn, amenable to mathematickal calculations; and we know the laws,” Daniel announced. “It is at least as well-founded as what you do for a living.”

They had come to a halt before the mouse-hole in the north side of Fleet Street that led to Crane Court. The driver maneuvered his team into it, giving directions to the other drivers that the baggage-cart alone should follow; the remainder of the train, consisting by this point of two large carriages and a second baggage-wain, were to remain in Fleet Street, and to get themselves turned around and aimed in the direction of Ludgate.

Getting the horses, their tack, and the carriage to pass through that archway was a bit like funneling a model ship, rigging a-luff, through the neck of a jug. At one point they drew to a full stop and Daniel, glancing out a side-window, found himself within kissing range of a pedestrian-gawky, post-smallpox, perhaps thirty years of age-whose advance down Fleet Street had been barred by all of Mr. Threader’s maneuvers. This fellow, who affected a ratty horse-hair wig, and who carried a smoky lanthorn in one hand and a staff in the other, peered in on them with frank curiosity that Mr. Threader found unseemly. “Go to, go to, sirrah, we are no concern of the Watch!”

The carriage moved forward into the narrow cul-de-sac of Crane Court.

“One of the Royal Society’s new neighbors?” Daniel asked.

“That watchman? No, I should think not!”

“Each inhabitant is supposed to take his turn on the Watch,” Daniel said pedantically, “and so I assumed…”

“That was twenty years ago when the Act was passed,” Mr. Threader returned, sorrowful over Daniel’s naivete. “It has become the practice for householders to pool a bit of money and pay some fellow-usually some caitiff from Southwark-to do the chore in their stead. As you encountered him this evening, so shall you every evening, unless you have the good fortune to pass by while he is in Pub.”

Still they were making their way, tentatively, down Crane Court. Once they had squeezed through the entrance, it had broadened slightly, to the point where two oncoming carriages might scrape past each other.

“I rather thought we should be leaving you off at the home of some distinguished Fellow,” said the bemused Mr. Threader. “I say, you’re not on the outs with them, are you?” he jested, trying to terminate their journey on a jolly note.

I shall be soon enough. “I have several invitations in my pocket, and mean to spend them methodically-”

“Like a miser with his coins!” said Mr. Threader, still trying to haul Daniel up to the level of joviality that he considered suitable upon parting; perhaps this meant he wanted to see Daniel again.

“Or a soldier with his pouch of balls,” Daniel returned.

“You may add one more!”

“I beg your pardon?”

“Invitation! You must come and lodge with me for a few days, Dr. Waterhouse; I shall take it as an affront if you do not.”

Before Daniel could think of a polite way to beg off, the carriage came to a stop, and at the same moment the door was pulled open by a fellow Daniel assumed was a porter, albeit over-dressed for the job in his Sunday church-going togs. He was not a porter of the gorilla type, but rather tall, of reasonably normal proportions, perhaps forty-five years old, clean-shaven, almost gentlemanly.

“It is I,” Daniel volunteered, as this man could not seem to decide which of the two passengers was the honored guest.

“Welcome to Crane Court, Dr. Waterhouse,” said the porter, sincerely but coolly, speaking in a French accent. “I am Henry Arlanc, at your service.”

“A Huguenot,” muttered Mr. Threader as Henry Arlanc helped Daniel down onto the pavement.

Daniel glanced at the front of the house that formed the end of the court, but it looked just like the engravings, which was to say, very plain and simple. He turned to look back towards Fleet Street. His view was blocked by the baggage-cart, which had taken longer to negotiate the entrance, and was still fifty feet away, lumbering towards them. “Merci,” said Mr. Threader as Arlanc helped him out.

Daniel moved over to one side so that he could peer between the baggage-cart and the line of house-fronts running down to Fleet. His night vision was not what it had once been, but he thought he could see the glimmer of the inquisitive watchman’s lanthorn limning the arch, perhaps three hundred feet away. He was bothering someone else now, someone in a sedan chair.

The luggage wagon suddenly got much larger, as if a giant bladder had been inflated to fill the entire width of the court. Daniel had scarcely registered that impression, when it became a source of light. Then it seemed a radiant yellow fist was punching at Daniel through a curtain of iron-colored smoke. The punch was pulled long before it reached him, and collapsed and paled into an ashy cloud. But he had felt its heat on his face, and things had flown out of it and struck him. Crane Court was now enlivened by the music of f?ry-bells as golden coins sought out resting-places on the paving-stones, and fell in twirling parabolas onto the roof-tiles. Some of them must have been flung straight up in the air for great distances because they continued to land hard and to bounce high for several seconds after Daniel had found his own resting-place: on his arse in the street. The court had been blocked off by a wall of smoke which now advanced to surround him; he could not see his own feet. But he could smell the smoke; it was sulfurous, unmistakenly the product of the combustion of gunpowder. Mixed in with that was a sharper chymical scent that Daniel probably could have identified if he had sniffed it in a laboratory; as it was, he had distractions.

People were calling names, including his. “I am all right,” Daniel announced, but it sounded as if his fingers were in his ears. He got to his feet, spry as a twenty-year-old, and began working his way down the court in the direction of Fleet Street. The air was clearer nearer the ground, and he ended up walking bent nearly double, tracking his progress by the passage of sprayed coins and other detritus under his feet. There was a kind of snow fluttering through the smoke as well: raccoon fur.

“Watchman!” Daniel shouted, “can you hear me?”

“Yes, sir! The Marching Watch has been sent for!”

“I do not care about the Marching Watch, they are too late! I want that you should follow that sedan chair, and tell me where it goes!”

No answer came back.

Mr. Threader’s voice came out of the smoke, just a few yards away. “Watchman, follow that sedan chair and I shall give you a guinea!”

“Right you are, sir!” returned the watchman.

“…or a guinea’s equivalent value in other goods or services, at my discretion, provided that timely and useful information, which would not have been obtainable through other means, is brought to me, and me alone; and note that nothing in this offer shall be construed to create a condition of employment between you and me, particularly where assumption of liabilities, criminal or civil, is concerned. Did you hear all of that, Dr. Waterhouse?”

“Yes, Mr. Threader.”

“It is so witnessed this thirty-first day of January, Year of our Lord 1714.” Mr. Threader muttered very rapidly.

In the next breath, he began finally to answer the hails of his assistants, who had come running up from Fleet Street and were now tramping blindly through the smoke all round, hardly less dangerous than the terrified horses. Having found Mr. Threader and Daniel by nearly running them down, they began asking, repeatedly and redundantly, whether they were all right; which soon became annoying to Daniel, who suspected that they were only doing it to be noticed. He told them to instead go and find the driver of the baggage-cart, who had been airborne when Daniel had lost sight of him.