The usual discretions, I thought mirthlessly as, lying in bed an hour later, I remembered the shellac in which her seal-or a counterfeit of it-had been impressed. Alethea was, it seemed, still no more discreet as far as the Post Office was concerned: a puzzling bout of laxity, I thought, in someone otherwise obsessed with secrecy. At first I didn't take her warning too seriously. I even convinced myself, after the first couple of readings, that perhaps I was wrong and the letter had not been opened after all. But as I travelled back and forth from Shadwell the next day I had the impression-the vaguest impression-that I was being followed. Or perhaps only watched. There was nothing specific, only a series of peculiar incidents that I might not have noticed were it not for the letter, which, like so many things these days, had set my nerves on edge. The sculler that pushed off from the quay a bare moment after mine. The image of the figure behind me reflected in the door-window as Thimbleby and I pushed into the Old Ship to eat our dinner. The narrowed pair of eyes watching me through the slim gap in a shelf as I browsed the aisles of a bookshop later that afternoon on the Southwark end of London Bridge. Even Nonsuch House seemed somehow altered. People I failed to recognise entered and, after a few cursory glances along the shelves, departed without a purchase; others simply peered through the window before slipping back into the crowds. And as I stepped outside to raise my awning a man across the carriageway started almost guiltily to life, then sauntered away.

No, no, it was nothing. Nothing at all. Or so I had told myself, sternly, as I set out the next morning for Alsatia. But why, then, was I craning my neck every minute to peer behind us, fearing what I might see framed for a second in the tiny oval of the hack's quarter-light?

But nothing appeared in the window, and I had forgotten my mysterious pursuers-indeed, I had forgotten almost everything else, including Alethea and her 'matters of some importance'-as I pushed past the waiter and stepped through the door of the Golden Horn.

At nine o'clock precisely Dr. Samuel Pickvance stepped forward to a table, rapped its surface sharply with a mallet and cleared his throat for silence. He was in perhaps the fortieth year of his age, a tall, emaciated man with a widow's peak, a conspicuous nose and thin, ascetic lips that seemed to be curled in a moue of contempt. He loomed before us on a raised platform, which he occupied like a magistrate on his bench, or perhaps more like a priest at the altar, wielding his mallet like a sanctus bell or aspergillum. He rapped it a second time, even more sharply, and the room at last fell silent. The ritual was about to begin.

I had slipped into one of the last available seats, in the back row, nearest the door. The Golden Horn was still dark except for its single rush-candle and a smoke-roiling beam of sunlight that fell obliquely across the room like a toppled girder. But Pickvance now produced a lantern, which he lit ceremoniously with a taper produced by his assistant, a young man with reddish hair. Now the row of heads in front of me sharpened into detail, including that of the automaton in the corner. It grinned back at me, smug and clever.

Entering the room a few minutes earlier I had discovered myself in the midst of one of those milling crowds so loved by pickpockets. Most of the assembly had been claiming the forty-odd chairs that were arranged in rows before the platform, on which stood the table and, a minute later, Pickvance and his altar-boy. I had been expecting to recognise someone-one of my clients, perhaps, or another bookseller or two. But I didn't recognise a soul, not even when the lantern was lit. And I was taken aback by what I saw. Pickvance's audience-for so we seemed-did not look especially different from the patrons I had seen here two nights before; indeed, it could have been the same group, for all I could tell. Most were dressed in leather breeches and rucked linen, with broken felt hats jammed low on their brows; a few others wore the black homespun and grim expressions of Quakers or Anabaptists. Curiously enough, a few Cavaliers were also present among them, looking prosperous and wicked, smirking to themselves or winking lewdly at one another, legs crossed, V-shaped beards neatly cultivated. What mysterious enterprise could possibly have banded together such an ill-assorted company?

But when the auction commenced and the first of the lots were cried, I realised why I failed to recognise anyone-why I hadn't seen any of them in my shop and why there were no booksellers among them, or at least none of the reputable booksellers I knew. Dr. Pickvance wasn't so much a priest or a magistrate, I decided, as a mountebank perched at his stall in Bartholomew Fair, hoodwinking a gullible audience. He was either an ignoramus or a cheat, because even from the back of the room I could see that he was embellishing and inflating each of the volumes which his assistant, introduced as Mr. Skipper, held up for viewing. It was an outrage. Books bound in ordinary buckram or even plain canvas were called 'the finest doublure' or 'most excellent crushed levant', while everything else on show was 'hand-tooled', 'repoussé', 'opulent' and 'exquisite', with 'Aldine' this and 'Plantinus' that, bound specially by 'the late King Charles's binder' or even 'the incomparable Nicholas Ferrar of Little Gidding'.

I was tempted to stand up and expose the grotesque canard, but everyone else seemed to have fallen under Pickvance's spell. He often started bids at a penny or two, but they quickly rose to a shilling, then to a pound, and within a minute or two the mallet would be resounding and our perverse auctioneer shouting in triumph: 'Sold! For thirty shillings! To the gentleman in the second row!'

So appalled was I by this hoax that two or three lots had been sold before I realised what type of volume was being offered. The first ones had been bound collections of political or religious tracts, including pamphlets by such persecuted sects as the Ranters, the Quakers and, most numerous of all, the Bunhill Brethren-works, in other words, that would have run foul of the Blasphemy Act passed by Parliament ten years earlier. No respectable dealer would touch them for this very reason, at least no dealer who wished to remain in business for long, because the Secretary of State regularly sent his searchers into the shops to root out and burn whatever blasphemous or seditious books and pamphlets they might lay their hands on.

So this was the reason, I supposed, why Dr. Pickvance held his auction in the Golden Horn-to escape the eyes of the searchers. For obviously none of his wares had been licensed by the Secretary of State. Yet this lack of sanction failed to deter the bidding one bit. I watched in amazement as the black-garbed sectarians competed for the pamphlets against a couple of smirking, rosecake-scented Cavaliers who appeared to regard even the most lubricious of the Bunhill Brethren's exhortations as some sort of joke. But I supposed the searchers were no more likely to enter Alsatia than were the bailiffs and catchpoles, so we were safe-if that was the word-from the graspings of the law.

Soon the lots grew more shocking, the bidding even fiercer. After thirty minutes the lots began to include hastily executed woodcuts and engraved prints depicting in the most vivid detail unchaste performances by masters with their kitchen-maids, or between ladies and their coachmen and gardeners. Others consisted of slim volumes of decidedly amateur verse describing a series of similar partnerships, along with prose volumes of specious medical authority illustrating inventive but surely impossible sexual postures that guaranteed, to the acrobats who attempted them, delights of a barely credible measure.