Newton and the Counterfeiter by Thomas Levenson Page A

axiom that bad money drives out good. The crisis was driven by a peculiarity of England's coinage, the fact that for almost three decades the country had two types of money in circulation: the hand-struck coinage produced up to 1662, and the coins manufactured since on machines installed in the Mint that year.
    The older currency, struck by a Mint moneyer swinging his hammer, was irregular and prone to wear. Worse, it had smooth rims, which meant that anyone with a good pair of shears and a file could snip the edge of a coin and then file the piece smooth again. A cut here and a slice there and pretty soon a coin clipper could accumulate a healthy pile of silver, at the expense of a debased currency.
    Clipping became epidemic in the 1690s, to the point that at the height of the crisis, "it was mere chance whether what was called a shilling was really ten pence, sixpence, or a groat," according to the Victorian historian Lord Macaulay. In one test of the state of the currency, Macaulay reported, "Three eminent goldsmiths were invited to send in a hundred pounds each in current silver to be tried by the balance." That much money, he wrote, "ought to have weighed about twelve hundred ounces. The actual weight proved to be six hundred and twenty four ounces." And so it went throughout the kingdom: money that should have tipped the scale at 400 ounces actually weighed 240 ounces at Bristol, 203 at Cambridge, and, at rival Oxford, a mere 103.
    Clipped coinage was hardly new: it had been punished as high treason since Elizabeth's reign. Ever since, clippers were regularly caught, tried, and condemned to death by the rope or by fire, but with little effect, especially in the orgy of clipping that took place between 1690 and 1696. As Macaulay wrote, the news that one condemned clipper was able to offer six thousand pounds for a pardon "did much to counteract the effect which the spectacle of his death was designed to produce."

    There was a still faster route to wealth available to those with access to more sophisticated tools. By 1695 counterfeit money accounted for about ten percent by value of all coins in circulation. The secret of that success lay in the counterfeiter's ability to crack the second and more formidable of England's two types of legal currency.
    London had seen nothing like the new moneymaking machinery the Mint installed in 1662. The ubiquitous Samuel Pepys, then secretary to the Navy Board, wangled a personal tour on May 19, 1663. In the narrow Mint rooms crammed alongside the outer wall of the Tower of London, he saw an extraordinary spectacle of heat, noise, smoke, and men pushed to the point of collapse as they raced to keep up with the pace of the giant machines.
    In the first room he toured, Mint workers tended intense charcoal fires beneath iron cauldrons, each large enough to melt up to a third of a ton of silver bullion at a time. Other workers poured the liquid metal into sand molds to make small rectangular ingots. Once the ingots cooled, the machines took over. Men broke the molds and passed the silver blocks through huge, crushing rolling mills, powered by horses driving giant capstans one story below. The thin plates that emerged went to lever-driven punches that pounded out round discs to be flattened by a screw press.
    Pepys noted approvingly that the new money was "neater ... than the old way," displaying an unprecedented level of consistency. By law, each shilling was supposed to contain a precise weight of silver, and this mechanical approach linked the symbolic claim of value on the face of the coin—the marks on the coin that declared "this is a shilling"—to the material promise: "this coin contains 88.8 grains of silver, value, twelve pence."
    The next machine down the production line was the key to the Mint's ultimate goals and was "the great secret," wrote Pepys, who wasn't allowed to see it. It was one of the earliest edging machines to be used for a national currency. It worked by