Finally Mr. Threader steps back from the table, hands upraised like a priest’s. “I say,” he intones, “that on the pan of yonder scale is a sample of metal fairly chosen from the coins in the Pyx, weighing twelve grains exactly; and I invite the Fusour to assay it.”

William Ham steps up.

William has not worked as a goldsmith since he was a boy. But like his father before him he’s a member in good standing of the Company. Daniel reckons that they tapped him as Fusour for a reason: he defied Sir Isaac and the King’s Messengers in the Bank of England a few days ago, asserting that they had no right to enter the vault and seize a deposit. They honor him for it now. This steadfast Goldsmith protected the sanctity of England’s commerce by his actions in the bank, and now he’ll perform a like service by challenging the produce of the Mint.

He has been at work preparing some necessaries over by the furnace. He approaches the Scale now carrying a wooden tray between his hands. On the tray are a sheet of lead, hammered out to a thin irregular disk, like a miniature pie-crust; a bullet-mold; pliers; and a cube of gray-white material rather less than an inch on a side, with a round depression in its upper surface. William Ham sets this down before the scale and tilts the scale-pan so that the twelve grains of gold-bits slide off and shower down into the center of the leaden sheet. He then folds the sheet together to imprison the gold, and wraps it up into a lumpy wad about the size of a hazelnut. He places this into one half of the bullet-mold, settles the other half over it, and squeezes the mold together with the pliers. When the packet comes out it has been rendered almost perfectly spherical: a wee globe, less like the Earth than the pitted gray Moon. He sets this into the depression in the top of the cupel-for that is the name of the cube of burnt bone ash. The sample fits into this neatly, recalling diagrams Daniel once studied in Geometry of spheres inscribed within cubes. William carries the tray over and sets it beside the furnace. A pair of tongs awaits. He uses these to pick up the cupel and thrust it into the heart of the furnace. It is dark and gray at first, but in a few moments it begins to absorb and then to give back some of the radiance in which it’s immersed. The lead softens and sags. William Ham consults his watch. A dome of surface tension forms in the cupel as its contents become liquid. The gray ash darkens as the molten metals saturate it.

Written right on the gold trial plate is the following: This standard composed of 22 carracts of fine gold, 2 carracts of alloy in the pound troy of Great Britain made the 13th day of April 1709. The late Sir Isaac Newton begged to differ-he suspected that the true numbers were more like 23 and 1, and that the goldsmiths had fixed the plate to make it more likely he’d fail the Trial-but in any case, the point is that Sir Isaac’s guineas are supposed to be made almost entirely of gold, with small amounts of base metals permitted. That is to say that out of the twelve grains of guinea-shards that made up the sample, eleven grains (if the inscription on the trial plate is taken at face value) or more (if the Goldsmiths fudged it) must be pure gold. The way to verify this is chymically to separate the gold from the not-gold, then weigh the former. The Company of Goldsmiths learned, ages ago, that when an assay is made in a cupel according to this receipt, the base metals in the sample will dissolve into the lead and be drawn, along with it, into the bone ash, like water into a sponge. But the pure gold will remain aloof, and form an ingot in the depression in the cupel’s top. And that is what happens now, before the eyes of Daniel and all the Jurors. Though it is an everyday procedure, it seems nearly as magical, to Daniel, as what occurred a few moments ago in the sedan chair. The release of the body of pure radiant gold from the dissolving globe of lead reminds him of the dream-vision of which Princess Caroline spoke.

If the assay is left in the furnace for too long, the gold will evaporate and lose weight, which is not fair to the Master of the Mint. If it is not left in long enough, some base metal will remain allayed with the ingot of gold, which is not fair to the King. Knowing how long to leave it in there is a black art of the Goldsmiths, and Daniel gets the sense that William is silently polling the other eleven members of his Jury for their opinions. When a consensus seems to have been reached, he picks up the tongs again and withdraws the cupel and sets it on a brick to cool down. The lead jacket has vanished and the cupel has turned charcoal-gray. Remaining in the top of the cupel is the ingot: a tiny round lake of gold. The stars and moons that decorated Mr. Threader’s black firmament have been changed by alchemy into this little sun. They need only wait for its heat to subside before they take the weight of it.

HOLBOURN OUGHT TO BE the Valley of the Shadow of Death for Jack. Perhaps he’d see it that way if he were facing forwards, watching Tyburn creep toward him. But they’ve faced him the other way, towards the London he’s leaving. There is intended to be a message in this: he is supposed to be looking back ruefully on his traitorous doings. But it is not working out thus. Jack is a spark dragged through a trench full of gunpowder. Far from being the Valley of the Shadow of Death, it is a roaring flume of vibrant riotous life, perfectly arrayed for viewing by Jack, and as such, a great distraction for one who really ought to be attending to his sins.

He does not recognize any one person in particular, but London, as an entire thing, is as familiar to him as the faces in a parish church, on Sunday morn, would be to an aged vicar. Groups are recognizable too. There’s a battalion of fishwives, of approximately regimental size, who have outflanked the artillery batteries at the Bridge and, by a covert march along Chick Lane, worked their way round to the west bank of the Fleet. There they seem to have divided into companies and squads, and mustered themselves within striking-distance in such places as Saffron Hill, the Dyers’ Court, the Plough-Yard, and Bleeding Heart Court. These are tributaries that empty into Holbourn along the hill that climbs up from the Fleet crossing, where the Hanging-March is doomed to move slowly. Triggered by the westward-propagating Mobb-roar, the fishwives mount vicious sallies from their nests and burst into the road, shouldering between the pikemen and the dragoons, pulling fistfuls of black coins from their aprons and flinging them at Jack’s head. They pock the sledge like grapeshot, they ricochet and ring in the air like f?ry-bells. Jack rips a button from his coat and underhands it to a fishwife who has actually penetrated to within a few yards of the sledge. She’s too astonished to do anything but clap it out of the air. A knot of fish-guts strikes him square on the bridge of the nose. He returns fire with another golden button.

Having beaten back the assault of the Fishwives’ Regiment with only light casualties, they crest the hill and enter into the widest part of Holbourn, which runs for a mile to St. Giles’s, passing between diverse expensive squares, all converted from cow-pastures during Jack’s lifetime. A Puritan in a black frock stands up on the street-island at Holbourn Bar, holding a Bible over his head, open to some passage he guesses Jack should know about. Another breaks through the cordon and climbs into the sledge with Jack and gets ready to baptize him with a bucket of water he’s brought along; but the Ordinary of Newgate, who’s been riding in the cart, isn’t having any of that. He’s down on the pavement in a trice, hustling along beside the sledge, and makes a grab for the handle of the Baptismal pail. This leads to a tug-of-war, and creates enough of a diversion that a short procession of Catholics-or so he assumes, from the monks’ robes they’re all wearing-is able to slip in, and make itself part of the parade. One is a priest, the others are burly monks, which makes perfect sense as a lone Papist wouldn’t survive for ten seconds in this crowd. The priest strides along behind the sledge, looks Jack in the eye, and begins to declaim rapidly in what Jack assumes is Latin. Jack is being given last rites! A very considerate gesture on someone’s part. This tiny and intrepid Popish strike force was probably despatched by Louis XIV from a secret chapel-headquarters in a vault beneath Versailles.