A 'mad gasser' prowled Mattoon, Illinois in 1944

What made it believable

It is easy, looking back with the comfort of a settled verdict, to forget how reasonable it was for Mattoon's residents to be afraid. Taken on its own terms, the case for a real prowler was not absurd, and treating the townspeople as simply foolish misses what actually happened to them.

The symptoms were not invented. People who called police were not lying or performing. They woke up nauseated, light-headed, with a foul taste and a genuine weakness in their legs that in some cases lasted through the night. Whatever caused it, the distress was real, and dismissing frightened residents as hysterical in the pejorative sense, as though they were being irrational or dishonest, is neither accurate nor fair to what they went through.

There was a specific, named eyewitness. Bert Kearney was not an anonymous rumor; he was a named man who told police, on the record and on the first night of the panic, that he had seen a particular figure and pursued him. A credible witness describing a specific person at a specific window is precisely the kind of detail that a purely psychological event should not produce.

It had happened before. A decade earlier, in Botetourt County, Virginia (1933–34), residents near Haymakertown and Troutville reported an almost identical pattern: a foul gas sprayed into homes at night, sudden illness, and a terrified community that armed itself and patrolled the roads. The county board of supervisors even offered a $500 reward for the attacker. That two unconnected communities, a decade apart, produced strikingly similar reports is, on its face, at least suggestive of a real recurring phenomenon rather than pure coincidence.

Even the officials who ultimately closed the case admitted part of it was real. On September 12, 1944, the same day his department's doubts about the case became public, Police Chief C. E. Cole told reporters that at least some of what residents smelled could be traced to industrial solvents drifting on the wind: carbon tetrachloride or trichloroethylene, both sweet-smelling and both capable of causing nausea and dizziness, from the Atlas Imperial Diesel Engine Company's Mattoon plant, which used both chemicals that year to clean artillery shell casings for the war effort. A week earlier, in the same breath as he first floated the word “hysteria” to the press, Mattoon City Commissioner Thomas V. Wright had put the case's central tension into words: “There is no doubt that a gas maniac exists and has made a number of attacks. But many of the reported attacks are nothing more than hysteria.” When the very officials who would go on to call this hysteria were themselves on record saying a real, physical cause explained at least part of it, the residents who reported genuine symptoms deserve to be taken at their word about what their bodies actually experienced, whatever ultimately caused it.

Decades later, one researcher stopped hedging with vague talk of a “man with a chemistry background” and put a specific name to the theory. In a self-published 2003 book, Illinois high-school science teacher Scott Maruna argued that the real gasser was Farley Llewellyn, a University of Illinois-trained chemist who kept a home laboratory and was, by multiple accounts, ostracized by much of the town, and whom Maruna describes as tall and thin, matching Bert Kearney's description of the figure he chased from the window. The theory has never been substantiated with physical evidence and Llewellyn was never charged with anything, but Maruna's book is a considered, book-length argument that a real, identifiable person, not a townwide delusion, was behind at least some of what Mattoon experienced, and it remains the most detailed dissent from the hysteria verdict that any researcher has published.

No gasser, no gas, no device

Set against the frightened reports is a simple, stubborn fact: in two weeks of intensive investigation, nobody (not the Mattoon police, not state investigators, not a single resident among dozens of self-appointed night patrols) ever produced a gasser, a gas, or a device capable of producing one.

The physical evidence never held up. Police collected a cloth reportedly used in one of the attacks and had it chemically analyzed; it yielded nothing. No spray canister, no residue, no plant matter or industrial chemical was ever recovered that matched the reported effects. Chemists consulted at the time were, in Donald Johnson's words, extremely skeptical that any gas existed which could cause sudden leg paralysis and nausea and then dissipate without a trace, leaving no lasting harm and no detectable residue in a home.

Mundane explanations accounted for many reports. Mattoon Police Chief C. E. Cole, after canvassing the reports, concluded that a number of them traced to ordinary household smells (spilled nail polish remover, cleaning solvents) or to fumes carried on the wind from nearby industrial plants, misidentified in the dark by residents already primed to expect an attack. Several of the men initially treated as suspects turned out to be, in the department's own assessment, amateur chemists or eccentric locals with no connection to any of the actual incidents.

The specific industrial source Cole named could not have caused it, either. Atlas Imperial Diesel Engine Company management said the plant kept only five gallons of carbon tetrachloride on site, held in firefighting equipment, and that any quantity of trichloroethylene large enough to sicken people blocks away would have sickened the plant's own workers first, none of whom reported the gasser's symptoms. A state health department inspection shortly before the panic began had certified the plant safe, and no leak, spill, or contamination was ever documented there. Cole's instinct that something ordinary and airborne explained part of the wave may well have been right about a handful of reports, but the one specific industrial source he named publicly was not it.

The pattern matches the newspaper, not a criminal. Johnson's 1945 field study, published in the Journal of Abnormal and Social Psychology, traced how most self-reported victims had first heard of the “gasser” through the Journal-Gazette's own front-page coverage, the same paper that broke the Kearney story and then escalated it daily. Reports rose in lockstep with the sensational headlines and fell just as sharply once the paper itself published a more skeptical piece on September 11 and police went public with their doubts the next day. A real, roaming attacker with a working gas weapon does not usually take his cues from a newspaper's editorial calendar; a socially transmitted panic does, almost exactly.

Later peer-reviewed work reinforced the same conclusion. In 2004, sociologists Robert E. Bartholomew and Jeffrey S. Victor revisited the case with additional interviews and archival material in The Sociological Quarterly. They proposed the term “collective anxiety attack” to describe how a shared belief in a threat, not a shared physical exposure, can produce real, synchronized physiological symptoms such as hyperventilation, dizziness, and weakness across a population primed by rumor and wartime stress. Their reexamination did not overturn Johnson's diagnosis; it sharpened it, and it remains the most detailed peer-reviewed treatment of the case.

Naming a suspect does not supply the missing evidence, either. Robert Bartholomew, the same sociologist whose 2004 reexamination anchors this case's academic literature, has flatly rejected Scott Maruna's theory that Farley Llewellyn was the real gasser: “Anyone who carefully examines all of the evidence and still thinks there was a real gasser is living in fantasy land. The evidence for mass hysteria is overwhelming.” Maruna's book identifies no chemical residue, no purchase record, no confession, and no witness placing Llewellyn at a specific scene; its case rests on his reputation as a town outcast with a home chemistry lab, a description that could fit other Mattoon residents who were never treated as suspects at all. A profile that matches a theory is not the same thing as evidence that supports one.

Even the Bert Kearney sighting, taken seriously on its own terms, does not survive scrutiny as proof of an attacker: officers who searched the area that night and in following days found no footprints, no discarded equipment, and no corroborating witness, and Kearney's report arrived at the very moment the story was first breaking: the point at which suggestion and adrenaline are hardest to disentangle from observation.

A frightened town needed a name for its fear

None of this means Mattoon's residents were foolish, dishonest, or uniquely suggestible. Mass psychogenic illness is not a story about gullible people; it is a well-documented, recurring feature of how frightened communities process ambiguous threats, and Mattoon happened to have nearly every ingredient that makes it likely.

The moment was already anxious. Late summer 1944 meant a war still underway, husbands and sons deployed overseas, blackout habits and wartime vigilance already normalized, and a home-front population primed to watch for danger in the dark. Ordinary bodily sensations (a wave of nausea, a stress headache, a moment of dizziness on standing up too fast) are common and usually go unremarked. Give an entire town a vivid, specific script for what those sensations mean, and some fraction of people experiencing them night after night will, quite sincerely, recognize themselves in that script.

The newspaper supplied the script, and then the rest of the town supplied the confirmation. Once the Journal-Gazette named the first “victims” and described their exact symptoms in vivid detail, every reader who later felt unwell had a ready-made explanation on hand, complete with a villain. Neighbors talking to neighbors, and armed patrols trading rumors on porches at night, turned individual anxiety into a shared, self-reinforcing belief, precisely the dynamic Bartholomew and Victor later formalized as a collective anxiety attack.

Believing in a prowler was, in a strange way, less frightening than the alternative. A gasser is at least a comprehensible enemy: a person, however elusive, who can in principle be caught, patrolled against, or reasoned with. The real explanation, that an entire community's fear had become physically contagious with no external cause to catch, is a harder, stranger thing to accept, then and now. It asks people to distrust their own senses rather than a stranger at the window, and that is a much less comfortable trade.

The story also had an obvious economic and narrative pull for the paper that broke it. Sensational front-page coverage sold copies and drew wire-service attention to a small city that would otherwise have gone unnoticed; once the Journal-Gazette had invested in the story, each new report was more newsworthy than a retraction, until, to its credit, the paper itself published the skeptical turn that helped end the panic.