Newton and the Counterfeiter

For the last half of Newton's adult life, 30 years, he was warden of the Royal Mint as well as Master of the Mint.

Although the post was intended to be a sinecure, Newton took it seriously. By the time of his appointment the currency had been seriously weakened by an increase in clipping and counterfeiting during the Nine Years' War to the extent that it had been decided to recall and replace all hammered silver coinage in circulation. The exercise came close to disaster due to fraud and mismanagement, but was salvaged by Newton's personal intervention. Newton's chemical and mathematical knowledge proved of great use in carrying out this Great Recoinage of 1696, a process that was completed in about two years. Newton was subsequently given the post of Master of the Mint in 1699, a post worth between £1,200 and £1,500 per annum.

Despite counterfeiting being considered high treason, punishable by hanging, drawing and quartering, convicting even the most flagrant criminals could be extremely difficult. Undaunted, Newton conducted more than 100 cross-examinations of witnesses, informers, and suspects between June 1698 and Christmas 1699. He himself gathered much of the evidence he needed to successfully prosecute 28 coiners.

One of Newton's cases as the King's attorney was against William Chaloner. Chaloner's schemes included setting up phony conspiracies of Catholics and then turning in the hapless conspirators whom he had entrapped. Chaloner made himself rich enough to posture as a gentleman. Petitioning Parliament, Chaloner accused the Mint of providing tools to counterfeiters (a charge also made by others). He proposed that he be allowed to inspect the Mint's processes in order to improve them. He petitioned Parliament to adopt his plans for a coinage that could not be counterfeited, while at the same time striking false coins. Newton put Chaloner on trial for counterfeiting and had him sent to Newgate Prison in September 1697. But Chaloner had friends in high places, who helped him secure an acquittal and his release. Newton put him on trial a second time with conclusive evidence. Chaloner was convicted of high treason and hanged, drawn and quartered on 23 March 1699 at Tyburn gallows. Then, he was publicly disemboweled.

Due to his income from the Mint Newton became very wealthy, although he lost a substantial sum in the collapse of the South Sea Bubble. Newton's niece Catherine Conduitt reported that he “lost twenty thousand pounds. Of this, however, he never much liked to hear...” This was a fortune at the time (equivalent to about £3 million in present-day terms), but it is not clear whether it was a monetary loss or an opportunity cost loss.

I read this in conjunction with listening to Newtons Law podcast. I also listened to a dramatised account of his time at the Mint. This was Isaac Newton - Nemesis.