The Motor That Ran for Twenty-Six Years on a Secret Room Full of Compressed Air

What happened?

John Ernst Worrell Keely was a Philadelphia carpenter, painter, and former theater-orchestra musician with no scientific training when he began, around 1872, inviting visitors to his laboratory to witness something extraordinary. He called it an “etheric generator.” On November 10, 1874, he blew into a nozzle for half a minute, poured in five gallons of tap water, made some adjustments, and produced a pressure reading of 10,000 pounds per square inch on a gauge — proof, he said, that he had disintegrated the water and released a mysterious vapor from the “interatomic ether,” a force he claimed was roughly four times lighter than hydrogen and nearly boundless in energy. The witnesses were impressed enough to form a stock company on the spot, paying $50,000 in cash for regional rights to the invention. Word spread, and the Keely Motor Company was soon incorporated in New York with a stated capital of $5,000,000 — worth roughly $95 million in today’s money.

Over the next two decades, Keely kept the demonstrations coming, and kept changing his story. His “vibratory generator” became a “hydro-pneumatic-pulsating-vacu-engine,” then “quadruple negative harmonics,” then, after 1887, an unnamed force based on “vibratory sympathy.” In 1884 he fired a “vaporic gun” at Sandy Hook for government officials, sending a lead ball through spruce planks using what he said was compressed etheric vapor. In 1885 he ran a rotating iron globe to saw wood, telling a skeptical reporter he’d once kept the same device running for 40 days straight — then, challenged to simply let it spin for half an hour, watched it lose power and stop after less than fifteen minutes.

Keely’s most important supporter was Clara Jessup Bloomfield Moore, a wealthy Philadelphia widow who met him in 1881 and became his patron, eventually giving him

He died of pneumonia at his Philadelphia home on November 18, 1898, leaving an estate of about

Why was it strange?

The strange part isn’t that a con lasted this long — it’s how thin the evidence for it always was, and how little that seemed to matter. Keely refused every offer of a clean, controlled test: recharging an emptied reservoir in front of witnesses, letting his machines run longer than a few minutes, allowing anyone to open the sealed globes that supposedly held his force. Each time, he had a reason to say no. And each time, engineers, investors, and even some credentialed scientists let the demonstrations speak louder than the refusals. The Keely case shows how a good enough magic trick, repeated confidently for decades, can outlast an enormous amount of quiet skepticism — as long as nobody with the authority to stop it insists on pulling up the floor.

What did scientists learn?

Nothing about “etheric force,” because it didn’t exist — but the episode became a durable lesson in how to tell real science from its impersonators. Extraordinary claims about new forces of nature demand independent, reproducible testing under conditions the claimant doesn’t control, not private demonstrations staged by the inventor himself. Secrecy is itself a red flag: legitimate 19th-century physics, however strange it sometimes seemed, was published, argued over, and eventually replicated by outsiders. Keely’s story also lands in a specific historical moment worth noting: real, genuinely invisible forces — X-rays in 1895, radioactivity in 1896 — were being discovered around the same years, which made the public, and even some scientists, more willing to believe another unseen force might be hiding in plain sight. Distinguishing real anomalies from staged ones took exactly the kind of hands-on, adversarial investigation the Philadelphia Press eventually organized.

How does it affect us today?

The Keely Motor Company is now a textbook case for physicists, historians, and skeptics explaining why perpetual motion machines keep resurfacing, and why claims of “free energy” — a phrase still used in crowdfunding pitches and patent filings today — deserve the scrutiny Keely dodged for twenty-six years. The thermodynamics his device implicitly violated remain as solid now as they were unfashionable to invoke against a charismatic showman in 1874. His story is also a reminder of how unregulated 19th-century stock promotion could separate investors from their money for years with no mechanism to force disclosure — a gap that later helped build the case for state and federal securities regulation.

Fun fact

One member of the team that finally exposed Keely’s hidden air tank was Lightner Witmer, a University of Pennsylvania professor of experimental psychology. Witmer wasn’t there as a physicist — he’d founded the world’s first psychological clinic at Penn in 1896 and is widely regarded as the father of clinical psychology. Three years after inventing an entire field devoted to diagnosing the mind, he found himself standing in a torn-up basement, helping diagnose a fraud.

Sources

• John Ernst Worrell Keely — Wikipedia
• Keely’s Secret Disclosed; Scientists Examine His Laboratory and Discover Hidden Tubes in Proof of His Deception — The New York Times, January 20, 1899
• Keely Motor Company (1875) — Museum of Hoaxes
• Lightner Witmer — Wikipedia