number.
“In even years the Bank generally uses the first half of the month, and in odd numbered years, the second half.” He indicated the relevant characters. And here, Mr Holmes is a perfectly genuine London £10 note, essentially identical to that embodied in the new, stolen plates, bearing this cipher and in this example, the serial number 41512, as you can see from the impress; however this complex but consistent formula the thieves are most unlikely to fathom. “You will note, too, gentlemen, that the top, right and left edges of this particular note are not cleanly cut – or guillotined as we say – but exhibit the Portal’s manufactured deckled, or ragged edge of the paper; only the lower edge is sharply cut.
“This is on account of the notes being printed in pairs – two-up as we term it; the twin of this note will have been impressed immediately below on the same sheet, and after the cutting process between the two, will exhibit a sharp upper edge, with the right, left and lower edges remaining deckled and uncut. This effect, too, the villains will achieve with consummate ease as they are now in possession of the correct paper. They lack only a simple guillotine.
“My greatest fear, however, is that any sequence of letters and numbers of apparently plausible appearance, correctly placed and overprinted, will not deter the criminal underworld from eagerly purchasing the notes at a discounted value and selling them on down a chain of ever-more petty criminals, until they start insidiously to flood the market.
“You will appreciate, Mr Holmes that large-scale forgeries of currency are rarely uttered – or circulated by the forger himself – rather, he passes that perilous risk on to lesser villains. Within my own lifetime, the penalty for circulating forged currency was hanging or transportation – this heinous crime quite rightly being regarded as high treason. However, I digress.
“Such lesser criminals will purchase counterfeit currency in exchange for, perhaps a forty percent amount of the face value; conceivably more if the forgeries are of an exceptionally high standard.
“These, as you now know, will be little short of perfection. Every £10 note in circulation, legitimate or fraudulent, will become suspect until checked by the bank.
“And what man, having been paid £10 for his services, will take the note to the bank to be verified, knowing full well that should the note be a forgery, it will instantly be confiscated and he will lose all, with no hope of recompense whatever?
“No, gentlemen, he will of a certainty retain it and pass it on in turn as settlement of his own obligations.
“That, Mr Holmes, in a very small nutshell is our very considerable dilemma. Time is now of the essence; somewhere a printing press may be running even as we speak.
“Clearly we cannot withdraw all the legal notes now in circulation, but unless you can use your powers to assist us in tracing the whereabouts of the stolen plates and paper before a deluge of counterfeit money makes its malign appearance we must, I fear, prepare ourselves for a national crisis of the very gravest proportion!”
* * *
CHAPTER THREE
Mr Nathan Madgwick
The parlour at 221B Baker Street fell silent. I was shocked by these startling revelations and their grim implications; Petch returned to rocking distractedly, his hands clenched tight until the bony knuckles showed white, while Holmes had reclined back in his chair, looking for the entire world as if he had fallen asleep, though I knew different.
I could almost hear that remarkable brain of his whirring like Babbage’s analytical engine running through numerous permutations of possibilities, most of which would of a certainty not appear worthy even of scant consideration by run-of-the-mill Yarders like Lestrade and Gregson.
But then again, Holmes was no run-of-the-mill Yarder.
Mr Henry Petch evidently mistook this apparent