Isaac Newton: Other side of the coin

2017 marks the 375th anniversary of the birth of one of the most famous Britons in world history. In this article, Newton’s lesser-known contribution to the UK’s numismatic heritage is explored.

By Justin Robinson

As a young man, Sir Isaac Newton rejected a career in the family farming business and instead became a great many things: a mathematician, astronomer, alchemist, bible scholar, author, professor, Member of Parliament, administrator, detective, prosecutor and Knight of the Realm. He was, first and foremost, a scientist and his contribution to our understanding of the universe is so significant that today, almost 300 years after his death, his name is still synonymous with genius.

A little known fact about the life of Sir Isaac Newton is that he had a lengthy association with The Royal Mint, serving as both Warden from 1696 to 1699 and then as Master from 1699 until his death in 1727.

English currency was in a very poor state when Newton arrived at The Royal Mint. Silver coins produced prior to 1662 had been hand struck making them susceptible to clipping, the practice of shaving off the edges in order to make new coins. To combat this, after 1662 The Royal Mint used a machine to strike coins that produced a decorated and milled edge. This dissuaded criminals from clipping coins but it didn’t stop the problem of counterfeiting, which continued on an industrial scale.

Solving the currency crisis

The currency faced an additional problem as the value of silver bullion on the continent was greater than the face value in London. As a result, vast quantities of coins were being melted and shipped abroad to be sold on the metals market for more than their face value.

Newton's solution to solve the currency crisis involved a Great Recoinage - an enormous operation that involved taking in millions of pounds of coins by weight and re-minting them at their correct value. Newton organized a production line of 500 men at the Tower of London, and over the next four years they smelted most of England’s money supply. To assist them, branch mints were established at Bristol, Chester, Exeter, Norwich, and York. Ever suspicious, Newton told the officers at these country mints to "trust not the computations of a single Clerk nor any other eyes than your own."

Newton's position as Warden of the Mint also meant that it was his responsibility to track down and prosecute counterfeiters. Chasing crooks was not something that particularly appealed to him, and he wrote a letter to the Treasury asking if he could be excused from this particular duty. When he found that he couldn't, he set to work with his customary zeal and single minded determination. To assist him, Parliament passed the Coin Act in 1696, making it an act of treason to make coins, construct, sell or possess equipment required to make coins, or to assist anyone else making coins. The punishment for doing so was death.

The ultimate penalty

Newton began to devote more and more of his time to his main duty of investigating and bringing to justice the counterfeiters and clippers that had bought the currency into disrepute. He went undercover himself and visited notorious bars, taverns and other dens of iniquity where criminals gathered, in order to recruit informants and obtain information.

Newton hired private "thief-takers" to locate counterfeiters and their equipment. Records also show that he personally tracked criminals to their lairs and interrogated them in person. He became a regular visitor at the rat-infested Newgate Prison, where he conducted more than 58 interviews, and between June 1698 and December 1699 records show that he personally conducted more than 100 cross-examinations of witnesses, informers, and suspects in order to build watertight cases against the accused. Newton gathered evidence to successfully prosecute 28 counterfeiters, most of whom went to the gallows and paid the ultimate penalty for their crimes. 

However, Newton's biggest challenge was to prosecute the most prolific counterfeiter of the age. William Chaloner had used his skills as a counterfeiter to become a very wealthy man. He lived in a large house in the semi-rural suburb of Knightsbridge, rode in a carriage, wore fine clothes and presented himself to high society as a gentleman. After forging "Birmingham Groats", he moved on to more lucrative Guineas, French Pistoles, crowns, half-crowns, banknotes and lottery tickets.

Slur on his reputation

Chaloner developed a sophisticated casting method that involved pouring molten metal into high quality brass moulds, and set up a factory in Egham, 20 miles outside London. He was so pleased with the quality of the coins he was producing that it upset him to see them used as it spoiled their perfection!

Ultimately, it was Chaloner's giant ego that proved his undoing. He wrote letters, published pamphlets and was even invited to appear before Parliamentary committees arguing that he alone could solve England's counterfeiting problem. He even went so far as to publicly accuse Newton of incompetence and possibly even fraud in his management of the Great Recoinage. Newton was furious at this slur on his reputation, and so began a game of cat-and-mouse in which Chaloner sought to persuade Parliament to let him run The Royal Mint while Newton secretly compiled evidence to expose him as the chief counterfeiter in England.

Newton discovered that Chaloner had been arrested repeatedly over the years for various scams and had even served time in jail for petty offenses. However, because there were no centralized criminal records at the time it had been easy for him to move from place to place and start again each time he was released. Astonishingly, Newton discovered that in 1694 Chaloner had actually been caught red handed in the act of forging banknotes but had been able to talk his way out of prosecution by naming who he claimed were the real counterfeiters behind the operation. He even ended up receiving a reward for his information!

Sentenced to hang

Newton dedicated himself solely to the task of building the strongest possible case against Chaloner. He methodically bribed, threatened and bullied witnesses for information that would allow his spies and informants to infiltrate Chaloner's sophisticated counterfeiting operation. Eventually there was enough evidence to arrest him. When the trial finally came, Newton had assembled eight witnesses for the prosecution. Chaloner had to conduct his own defence unaware of the evidence that Newton had compiled against him. Chaloner was sentenced to hang. 

From his condemned cell Chaloner wrote to Newton several times begging him to intervene and save his life. His final letter concluded with the piteous words; “Oh dear Sir nobody can save me but you. O God my God I shall be murdered unless you save me. I hope God will move your heart with mercy pitty to do this thing for me. I am Your near murdered humble Servant."

Newton did not respond and Chaloner suffered a miserable death choking on the rope to the amusement of the crowds at Tyburn. In his journal Newton wrote simply that ‘Chaloner could have lived a long, honest life had he let the money and Government alone.’

‘Fine work’ Guineas

Later that year the post of Master of The Royal Mint fell vacant and Newton accepted the position on Christmas Day 1699. He was determined to use the new minting technology available to him to create the best possible visual appearance of coins. He hired a skilled German jeweller from Dresden named John Croker to engrave designs onto the dies at a greater depth. The resulting die would then be used to strike coins in a higher relief, which would make the monarch’s portrait look more lifelike. The 2 Guinea and 5 Guinea struckin 1701 are known today as the “fine work” Guineas. They are a testimony to Newton’s determination to produce the best possible coinage, and have become numismatic classics.

The administrative skill of Newton is clearly demonstrated in the hundreds of surviving reports and letters that he wrote as Master. His most famous report, issued in September 1717 to the Lords Commissioners of His Majesty’s Treasury established a new mint ratio between silver and gold that had the effect of driving silver out of circulation and moving Britain onto the gold standard.

With silver coinage in such short supply there was an urgent need to issue a lower denomination gold coin. In 1718 it was decided to strike a gold quarter guinea worth approximately the same as the five-shilling silver crown. The new coin weighed 2.1 grams and was just 16 millimetres in diameter. Newton did not appreciate at the time that such a small coin would be impractical to use, which made them unpopular. Of the 37,380 coins that were minted many appear to have been put aside as keepsakes due to their beautifully intricate design. Production of the quarter guinea ceased within a year.

Newton was determined to ensure that all coins were made to the correct weight and fineness, varying as little as possible. This level of accuracy was unprecedented and it is arguably one of his greatest achievements as Master of The Mint that he brought the coinage, in his own words to a "much greater degree of exactness than was ever known before".

Abridged from the book ‘Isaac Newton – A Life in Colour’, available to purchase exclusively from The London Mint Office.