When you think of Sir Isaac Newton, what comes to mind? Do you see him serenely pondering gravity under an apple tree (a tree that is still alive, by the way)? Scribbling down the laws of motion while rocking a righteous wig? Possibly inventing the cat flap door?

Regardless of which Newtonian scene appears in your imagination, it’s a safe bet that it isn’t Newton storming through the alleys of London, collaring counterfeiters, interrogating criminals, and raining down Justice over yet another forged guinea.

Yes, Newton was a scientific juggernaut, but for a brief and glorious period in the late 1690s, he was also a combination Secret Service agent, master detective, and wielder of the avenging sword of justice. The man who became the canonical face of science textbooks also knew what it was like to be on the front lines, defending the realm against counterfeiters, as Warden of the Royal Mint.

Isaac Newton: From Sinecure to Swashbuckling

The post of Warden of the Mint had traditionally been the bureaucratic equivalent of a hammock in the sun—comfy and ceremonial, but rarely used and generally overlooked. When Newton took the post in 1696, most probably expected him to fulfill his responsibilities in a nice, relaxed manner. Our friend did not tend to approach too many things half-heartedly. He soon had more than a full time job, thanks to a massive overhaul in the way Great Britain handled its currency.

The Great Recoinage: When the Economy Got Clipped—and Newton Showed Up

By the late 1600s, England’s silver coins were looking more like crescent moons than proper currency. Thanks to decades of “clipping”—the charming habit of shaving little bits of silver off coins and spending the Swiss-cheesed remains at face value—the country’s money was quite literally falling apart. Combine that with a booming counterfeiting industry and a dash of government inaction, and the economy was lurching toward full-blown collapse. That bring us to the Great Recoinage of 1696.

Parliament’s solution was bold: melt down every single old silver coin and replace it with shiny, new, machine-minted ones. The new coins would have milled edges—making them harder to clip—and would, hopefully, restore confidence in the currency. All they needed was someone to oversee this Herculean effort. And who better to take on the gravity of the task than the man who coined the word “gravity” to start with?

Newton, the 17th century walking definition of “over-achiever,” tackled everything from logistics to criminal prosecutions. He increased coin production, supervised the melting and re-striking of millions of coins, and launched a personal war against counterfeiters, who were all too eager to exploit the monetary mayhem for personal gain. Newton wasn’t just making coins—he was restoring public trust in England’s money, one silver guinea and counterfeiting conviction at a time.

Thanks to Newton’s relentless work (and a few well-timed executions), the Great Recoinage managed to stabilize the currency. It wasn’t pretty. It wasn’t fast. But it worked. And in the process, the man who gave us the laws of motion also gave the British economy a much-needed jolt of Newtonian discipline.

Counterfeiting has always been a crime, but in late 17th-century England, it was as bad as you could get. Counterfeiting wouldn’t just land you a time in prison or a stern talking to from a cross-looking judge. It was treason and a capital offense. Counterfeiters could be hanged, but the sheer volume of fake currency meant enforcement was, well, uneven at best.

But then came Newton. Most previous Wardens had treated the job like a guest appearance—pop in, wave to the staff, collect the salary. Newton, however, took a different approach: he actually showed up. And worse (for the criminals), he cared.

Sherlock vs Moriarty (aka Newton vs Chalomer)

Newton threw himself into the murky world of forgers and fraudsters. He soon found himself running what can only be described as a one-man Scotland Yard. He questioned prisoners in Newgate Gaol, tracked down informants, and even received anonymous letters stuffed through his door like a Renaissance-era crime podcast host. At one point, he was juggling information on over two dozen suspects and commuting to ten separate sessions with the Lords Justices to untangle it all.

It isn’t difficult to image Newton in the role of Sherlock Holmes — 200 years before the fictional detective made his first appearance. Newton’s single-minded determination, penchant for science, and keen logical mind made him a nearly-unstoppable force for justice.

Of course, every Sherlock Holmes needs a Professor Moriarty as a nemesis—someone against whose warped ingenuity he can find a true challenge. It wasn’t long before Sherlock Newton found his arch-rival.

One of Newton’s earliest cases involved Peter Cooke, a gentleman (in title, if not in character) who had been sentenced to death for counterfeiting. Cooke, desperate for a stay of execution, offered up juicy allegations against his fellow criminals, hoping to gain leniency. It was from Cooke that Newton first heard about a shady operator named William Chaloner. And just like that, Newton had his first real adversary.

From Groats to Grifts: William Chaloner’s Early Hustles

Before he crossed paths with Isaac Newton, William Chaloner had already built quite the résumé. Born in 1650 in Warwickshire to a weaver with more patience than luck, young William showed promise early on—as a menace. His parents, thoroughly outmatched by their misbehaving son, offloaded him onto a nail maker in Birmingham, which just so happened to be the Las Vegas of counterfeit coin production in 17th-century England. And wouldn’t you know it? The kid took to it like he had been born for such a career.

In Birmingham, the “Birmingham groat”—a forged four-penny coin—was practically legal tender. Chaloner, barely old enough to shave (or even spell “honesty”), quickly became proficient in their production. But his ambitions didn’t stop at minor currency fraud, and those ambitions soon outgrew Birmingham. At some point in the 1680s, he relocated to London and immediately got to work exploiting every nefarious opportunity for enrichment.

Chaloner immediately made his own niche in the London economy. And what was that niche? It was… well… things that are rated R, at best, and certainly can’t be described in detail in this family-friendly article. Suffice it to say that in a time when Restoration England was rediscovering all the vices it missed during Cromwell’s rule, Chaloner saw a market need and did his best to fill it.

Chaloner hawked his tawdry wares to a clientele ready to embrace the bawdiness of the era. If Newton was the father of modern science, Chaloner was the godfather of NSFW side hustles.

Having thrust his foot in the door of the London Underground, he made the next move in the Chaloner Grift Parade: quack doctor and fortune teller. According to the gleefully untrustworthy yet endlessly entertaining 1699 Chaloner biography Guzman Redivivus, Chaloner had “the best knack at Tongue-pudding”—meaning, he could charm the corsets off his customers while divining the identities of stolen goods and potential husbands. Often, the trick to recovering those lost items was simple: steal them in the first place, then dramatically “discover” them for a modest fee.

There’s also a record that a “William Chaloner” married Katharine Atkinson in 1684 at St Katharine’s by the Tower and had several children. If this was our man—and it likely was—he tried domesticity for a hot minute before being suspected of robbery and having to flee his lodgings. At the risk of spoiling the ending, we should tell you that this pattern would repeat itself a few times.

By 1690, Chaloner had taken up work as a japanner (think early lacquerware finisher), where he likely learned the delicate art of gilding. Useful skill, that—especially if you’re planning to crank out counterfeit coins and want them to shimmer with a whisper of legitimacy.

By the time Newton came sniffing around in his Warden of the Mint hat, Chaloner was already a seasoned grifter. He’d forged, fleeced, prophesied, peddled, and pocketed more shady deals than you could shake a counterfeit shilling at. And he was just getting started.

The Rise of the Chaloner Crime Syndicate

Chaloner graduated from small-time grifting into full-blown criminal enterprise thanks to a colorful supporting cast: Patrick Coffey, a goldsmith with a flair for gilding; Thomas Taylor, an engraver with an artistic penchant for crime; and his own brother-in-law, Joseph Gravener. The crew cranked out French pistoles and English guineas from a semi-rural operation with a flair for metallurgy and an allergy to ethics. The distribution end was handled by Thomas Holloway and his wife, who funneled the coins into the hands of petty crooks for circulation. Efficiency, thy name was Chaloner.

Unlike Emerich Juettner, who famously thrived despite gaining the title of the world’s worst counterfeiter, Chaloner earned a reputation as one of the finest counterfeiters in England—not just for his volume, but for his quality. Newton described him as a ragged japanner who “in a short time put on the habit of a gentleman.” Indeed, Chaloner lived large: a house in Knightsbridge, a carriage, fine plate, and the wardrobe of a man who wanted to look honest without actually being honest. Naturally, he abandoned his family and shacked up with a female coiner named Joan Porter. Romance, but make it felonious.

Respectability for Rent

By 1692, Chaloner tried to launder not just money, but his reputation. He rebranded himself as a civic-minded whistleblower and started offering “solutions” to Parliament and the Royal Mint. He wrote pamphlets proposing deeper coin grooves, restricted access to tools, and suggested employing an officer who knew both smithing and skulduggery (he meant himself, of course).

Newton recognized that Chaloner was trying to gain the trust of Mint authorities so he could gain access to the secret techniques used to safeguard the currency. Rather than hand over government secrets, Newton applied his scientific mind to the problem and tested Chaloner’s suggested innovations. In doing so, he demonstrated how laughably impractical they were. Although Chaloner gained an audience before the Privy Council to make his pitch, Newton prevailed. And he was keeping notes.

When one of Chaloner’s earlier collaborators, William Blackford, was hanged for passing fake guineas and fingered Chaloner on the way down, Chaloner skipped town until the coast was clear. He resurfaced with a coining setup in Egham, outside London’s jurisdiction, where he and his team—moulding experts, metal workers, and professional liars—cranked out counterfeit coins until a loose-lipped associate ratted them out. Newton swooped in, flipped the informant into a double agent, and began closing the net.

Royal Mint? Royal Scam

Ever the opportunist, Chaloner targeted the very institution trying to shut him down. In 1695, with backing from disgruntled nobleman Charles Mordaunt, he accused the Royal Mint of corruption and incompetence—claims which, to be fair, weren’t entirely off-base. But when the Mint investigated, they discovered more evidence of Chaloner’s criminal empire than their own malpractice. By January 1696, he was in Newgate on suspicion of felony.

After trying to sell new allegations of Mint corruption to Chancellor Charles Montagu, and boasting about them to anyone who would listen (including under aliases like “Chandler”), Chaloner managed to talk his way into another audience. He accused Mint employees of everything from making underweight coins to loaning out official dies. The kicker? He claimed he had never made a guinea in his life. Even by 17th-century standards, that was a bold-faced lie—unless he was referring to an honest guinea.

Agent Provocateur, Professional Backstabber

Chaloner also tried to make a name (and some coin) as an anti-Jacobite informant. He staged stings, printed fake manifestos, and turned in anyone within reach—real or invented. He even fabricated a plot against Dover Castle and tried to blackmail the Secretary of State, which went about as well as you’d expect. In one case, he helped execute a rival thief-taker named Thomas Coppinger by double-crossing him to the authorities.

The Bank Job(s)

When the Bank of England began issuing £100 notes in 1695, Chaloner was first in line to forge them. He went so far as to obtain marbled paper to match the new design. The Bank caught on within two months and shut the program down—but not before Chaloner reportedly received £200 in rewards for pretending to help crack the case… which he had personally orchestrated. He also taught his sidekick Aubrey Price how to alter Exchequer bills, which led to Price’s execution in 1698.

That same year, Chaloner masterminded the engraving of fake lottery tickets for the government’s “malt tax” scheme. His associate, David Davis, snitched for a bounty, and Chaloner was thrown back into Newgate. Ever the survivor, he accused someone else of engraving the plate and offered to turn it over—for immunity, of course.

Newton Strikes Back

By early 1699, Newton had had enough. A scientist by training, sleuth by necessity, he continued to develop an airtight case. He recorded over 200 depositions, documented Chaloner’s counterfeiting escapades, and even employed jailed criminals to dig up dirt on their cellmate. Newton mobilized a spy network, and gathered witness statements from every disreputable character Chaloner had ever done business with.

Among his more colorful recruits was one Samuel Wilson, who used a warrant from Newton to blackmail suspects. Another, Thomas Holloway, accepted bribes to flee the country and dodge testifying against Chaloner. Newton chased down Holloway’s ship captain, the captain’s wife, and even the tavern keeper to piece together the story. Sherlock Holmes, eat your powdered wig-covered heart out.

Chaloner reportedly mocked him as “that old dogg, the Warden,” which, while rude, does suggest that even criminals understood Newton was more bloodhound than bureaucrat. And once the chase was on, Newton wasn’t letting go.

At last, his case was complete, and he brought indictments of high treason against his nemesis.

The Battle in the Courtroom

The trial was… messy. Despite Newton’s meticulous work, witnesses had dubious memories. The defense made much of the fact that the charges covered several coin types, but counterfeiters typically stuck to one denomination. Ultimately Chaloner’s rap sheet spoke louder than these troublesome issues.

Chaloner had to defend himself against eight of Newton’s handpicked witnesses. Realizing Newton’s strategy was closing in on him, Chaloner resorted to some innovative methods of his own. He insulted everyone in the courtroom, faked madness, and tried to argue jurisdictional technicalities. It didn’t work.

On March 3, 1699, the jury took only minutes to find him guilty of high treason. The next day, he was sentenced to death.

In a final twist, Chaloner—ever the dramatist—wrote a heartfelt plea to Newton, signing off as “your near murdered humble servant.” He begged for clemency. Newton didn’t blink. The King granted pardons to two criminals on the same day. Chaloner was not one of them. He was hanged on March 22, 1699.

With the noose tied around his neck, Chaloner’s body dropped at the rate of 32 ft/sec², thus demonstrating that Newtonian gravity —- like his pursuit of justice —- was more than theoretical.

Guzman Redivivus eulogized Chaloner as, “a Man, who had he squar’d his Talents by the Rules of Justice and Integrity, might have been useful to the Commonwealth; But as he follow’d only the Dictates of Vice, was as a rotten member cut off.”

The Newtonian Legacy of Law and Order

Newton’s efforts led to a sharp decline in coin-related crime. There were 19 executions for counterfeiting in 1697. By 1700, that number was zero. He proposed reforms like reducing the penalties for low-level “uttering” (passing fake coins) to actually get convictions, and pushed for stricter laws on those selling the tools of the trade. He even suggested a national commission to centralize prosecutions, pardons, and rewards—basically a 17th-century version of the Secret Service, minus the sunglasses.

Newton left behind a stronger, more secure institution. He formalized payments for informants, employed legal professionals instead of shady go-betweens, and made it a lot harder to sneak a fake coin past the Crown.

From Falling Apples to Foiling Felons

So yes, the same man who discovered gravity also made criminals fall—right through the trapdoor of the gallows. Isaac Newton wasn’t just a physicist, mathematician, and philosopher. For a brief window in time, he was also London’s most terrifying accountant-slash-detective.

He proved that being brilliant isn’t just about understanding the cosmos. Sometimes, it’s about chasing a forger through the backstreets of London, armed with logic, legal power, and a very long memory. And possibly a disdain for people who call you an “old dogg.”

For more information about Sir Isaac Newton, visit The Newton Project or read Newton and the Counterfeiter by Thomas Levenson.

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