Earlier this month, inside the barn at Hallockville Museum Farm, historian, author and journalist Bill Bleyer captivated a sold-out crowd with his account of how the American Revolution was won not just on battlefields, but with spies, coded messages and invisible ink.
His subject, explored in his new book George Washington’s Long Island Spy Ring, is the clandestine network now known as the Culper Spy Ring, a small, tightly-coordinated group of patriots operating behind British lines in New York City and across western Long Island.
Like many great American adventures, the spy ring was born out of failure.
In 1776, after George Washington’s crushing defeat in the Battle of Long Island, the Continental Army was driven out of New York City, leaving the British firmly in control. The loss exposed Washington’s critical weakness: no reliable intelligence.
“He had no idea what the British were going to do,” said Bleyer, pictured above.
Washington’s first major espionage mission was an epic fail, ending with the capture and execution of 21-year-old Nathan Hale. Hale’s mission proved the dangers of the solo agent model. Captured by the British near present-day Queens, Hale was taken to Manhattan and hanged without trial on Sept. 22, 1776, near what is now East 66th Street and Third Avenue.
Building the Culper spy ring
What Washington needed was a sustained, embedded intelligence network. By 1778, he and his young intelligence chief, Major Benjamin Tallmadge of Setauket, began assembling that team.
At its core were ordinary New Yorkers, including Abraham Woodhull, a farmer in Setauket, who served as the primary agent on Long Island; Robert Townsend, a Manhattan merchant who became the chief spy inside British-occupied Manhattan; Austin Roe, who carried intelligence by horseback from the Brooklyn Ferry to Setauket, and Caleb Brewster, a whaleboat captain who carried messages across Long Island Sound.
From there the messages traveled over land to Washington’s headquarters at West Point.
“This circuitous route, in the beginning, takes as long as three weeks to get a message one way,” Bleyer said. “So Washington complains throughout the war that the information he’s getting is spectacularly accurate and useful, but it takes so long to get to him that he often can’t do anything with it, because the situation has changed.
“So they try, throughout the war, to speed it up … to go more directly north and west, but it never works. They try going north into the Bronx, and they try going up from Port Washington [over the Sound] to Westchester, but every time they try it, it doesn’t work. People are captured. People get scared and run off, or they come back without useful information. So eventually, the Culpers just decide to stick with what they know.”
Codes, ciphers and invisible ink
The Culper Ring developed their tradecraft on the fly. Members adopted aliases. Woodhull was “Samuel Culper,” Townsend was “Culper Jr.” They used a numerical codebook developed by Tallmadge. George Washington was “711,” New York was “727,” and hundreds of common terms were converted into numbers.
“They were self-taught,” Bleyer said. “They are learning on the job.”
Their most innovative tool was invisible ink.
Early efforts used household substances, including lemon juice and milk, to write hidden messages. These could be revealed with heat, a vulnerability that made them risky.
That’s where James Jay, a physician, amateur chemist and brother of John Jay — the first chief justice of the Supreme Court — entered the picture. He developed a two-part chemical system: a “stain” that was invisible on paper and a counterpart solution that revealed it.
“So Washington is thrilled,” Bleyer said. “He loves it.
“But Jay said the ‘chemicals are hard to find, and they’re hard to mix without a big lab like I have in London.’ So Washington has his engineers build a lab for James Jay up on the Hudson and in Fishkill, and [gave] him a letter where [Jay] can go to any government or fort and get whatever chemicals he needs if they have them.”
Washington instructed his spies to write innocuous letters, with the real messages hidden in secret ink between the lines.
Intelligence that changed the war
The ring’s reports were often astonishingly detailed, down to troop numbers, artillery placements and British strategic plans, Bleyer said.
Among their most significant contributions was providing ongoing intelligence on British troop movements in New York, thwarting a British attack on Newport, Rhode Island and exposing a plot to flood the colonies with counterfeit Continental currency to the cripple the economy.
The intelligence was so precise at times that historians believe Townsend may have had sources inside British headquarters. Despite the delays in delivery, the intelligence repeatedly proved critical.
Postwar silence
After the war, the members of the Culper Ring largely kept their roles secret.
“They didn’t talk about it,” Bleyer said. “Not even to their families.”
The author said that “Benjamin Talmadge, who’s in charge of the whole thing, for instance, wrote two sentences in the autobiography he wrote for his children — not for publication. So they were very closed mouth about it.”
Bleyer said that espionage carried a stigma at the time and being labeled a spy, even for the patriot cause, could damage reputations permanently. Some things never change.
Much of what historians know today comes from more than 200 surviving letters, preserved despite Woodhull’s repeated pleas to the others to destroy them to protect the ring.
Suffolk County historian Morton Pennypacker was the first to document the Culper Spy Ring. Before his research in the 1930s, people knew vaguely that Washington had spies operating around New York and Long Island during the Revolution, but the identities of many of the participants were largely unknown or unproven.
Busting the myths
Bleyer devoted a significant portion of his talk, and his book, to dismantling popular myths that have grown around the spy ring.
The “Clothesline Code”
One of the most enduring legends involves Anna Strong, a Setauket resident who is said to have sent signals by hanging laundry on a clothesline, including black petticoats and white handkerchiefs that indicating meeting locations.
It’s a great story, Bleyer said, but “it never happened.”
Recent research shows the Strong family didn’t even own the property where the story is set during the Revolution. More practically, a messenger could have delivered the same information far more discreetly.
Agent 355
Another mystery centers on “Agent 355,” sometimes described as a female spy embedded in British high society.
In reality, Bleyer said, the historical record contains just a single reference to a “355,” which was simply a code for “woman.”
“We have no idea for sure who that women is.”
Popular accounts, particularly in Fox News host Brian Kilmeade’s The Secret Six, expand the story into a dramatic narrative involving romance, imprisonment, and death. Bleyer dismissed those claims as unsupported.
The Rivington theory
British printer James Rivington has been tied to the Culper Ring, Bleyer said, but while he may have quietly aided the patriot cause, there is “zero” evidence linking him to the ring itself.
The “Turn” effect
The AMC series TURN: Washington’s Spies brought widespread attention to the Culper Ring, but “it’s highly fictionalized,” Bleyer said. Among its liberties: invented romances, fabricated murders, and major alterations to timelines and character roles.
“I give it credit for popularizing the story. But it’s not history.”
Did the spy ring win the war?
Bleyer said that the biggest myth among claims made in some popular histories is the idea that the Culper Ring single-handedly secured American independence.
“That’s ridiculous,” he said, pushing back on claims made in some popular histories.
The consensus among historians is more measured: the ring was highly effective, arguably the most successful intelligence operation of the war, but it was one piece of a much larger effort.
Washington himself offered a mixed assessment.
During the war, he praised the intelligence as vital. Afterward, he complained about delays and costs, noting that reports were often “tedious.”
But he kept the operation running for years.