Dr. Samuel Johnson is today best known for his Dictionary of the English Language (1755), which remained the foremost authority on the English language until the Oxford English Dictionary appeared more than a century later. The dictionary took Johnson nine years to complete, for which he was paid the princely sum of 1500 guineas—equivalent to $300,000 (or £210,000) today. Although it wasn’t quite the commercial success its publishers hoped it would be, it allowed Johnson the freedom to explore his own interests and endeavors: He spent several years editing and annotating his own editions of all of Shakespeare’s plays, and traveled extensively around Britain with his friend (and eventual biographer) James Boswell—and, in 1762, helped to investigate a haunted house.

Johnson—who was born on this day in 1709 and is the subject of today's Google Doodle—had a lifelong interest in the paranormal, once commenting that he thought it was “wonderful” that it was still “undecided whether or not there has ever been an instance of the spirit of any person appearing after death. All argument is against it, but all belief is for it.” According to Boswell, however, he was more of a skeptic than an out-and-out believer, and refused to accept anything without seeing the evidence for himself. So when the news broke of an apparently haunted house just a few streets away from his own home in central London, Johnson jumped at the chance to perhaps see a ghost with his own eyes.

The haunting began in the early 1760s, when a young couple, William and Fanny Kent, began renting a room from a local landlord, Richard (or William—sources disagree, but for clarity, we'll use Richard) Parsons, at 25 Cock Lane in Smithfield, London. Soon after the Kents moved in, Richard’s daughter, Betty, began to hear strange knocking and scratching sounds all around the house, and eventually claimed to have seen a ghost in her bedroom.

Richard soon discovered that William was a widower and that Fanny was in fact his deceased wife's sister; under canon law, the pair couldn't be married, and Richard became convinced that the ghost must be that of William's deceased first wife, Elizabeth, blaming William’s presence in the house for all of the strange occurrences. He promptly evicted the Kents and the noises soon subsided—but when Fanny also died just a few weeks later, they immediately resumed and again seemed to center around Betty. In desperation, a series of séances were held at the Cock Lane house, and finally Fanny’s ghost supposedly confirmed her presence by knocking on the table. When questioned, Fanny claimed that William had killed her by poisoning her food with arsenic—an accusation William understandably denied.

By now, news of the Cock Lane Ghost had spread all across the city, and when the story broke in the press, dozens of curious Londoners began turning up at the house, queuing for hours outside in the street hoping to see any sign of supernatural activity. According to some accounts, Parsons even charged visitors to come in and “talk” to the ghost, who would communicate with knocks and other disembodied noises.

But with the suspicion of murder now in the air, the Cock Lane haunting changed from a local curiosity into a full-blown criminal investigation. A committee was formed to examine the case, and Johnson was brought in to record their findings and investigate the case for himself.

On February 1, 1762, one final séance was held with all members of the committee—Johnson included—in attendance. He recorded that:

About 10 at night the gentlemen met in the chamber in which the girl [Betty] supposed to be disturbed by a spirit had, with proper caution, been put to bed by several ladies. They sat rather more than an hour, and hearing nothing, went down stairs, when they interrogated the father of the girl, who denied, in the strongest terms, any knowledge or belief of fraud … While they were enquiring and deliberating, they were summoned into the girl’s chamber by some ladies who were near her bed, and who had heard knocks and scratches. When the gentlemen entered, the girl declared that she felt the spirit like a mouse upon her back.

But the committee were suspicious. Betty was asked to hold out her hands in front of her, in sight of everyone in the room:

From that time—though the spirit was very solemnly required to manifest its existence by appearance, by impression on the hand or body of any present, by scratches, knocks, or any other agency—no evidence of any preternatural power was exhibited.

Johnson ultimately concluded that it was “the opinion of the whole assembly that the child has some art of making or counterfeiting a particular noise, and that there is no agency of any higher cause.” And he was right.

As the investigation continued, it was eventually discovered that Richard Parsons had earlier borrowed a considerable amount of money from William Kent that he had no means (nor apparently any intention) of repaying. The two men had a falling out, and Parsons set about elaborately framing Kent for both Fanny and Elizabeth's deaths. The ghostly scratching and knocking noises had all been Betty’s work; she had hidden a small wooden board in the hem of her clothing with which to tap or scratch on the walls or furniture when prompted.

The Parsons—along with a servant and a preacher, who were also in on the scam—were all prosecuted, and Richard was sentenced to two years in prison.

Although the Cock Lane haunting turned out to be a hoax, Johnson remained open-minded about the supernatural. “If a form should appear,” he later told Boswell, “and a voice tell me that a particular man had died at a particular place, and a particular hour, a fact which I had no apprehension of, nor any means of knowing, and this fact, with all its circumstances, should afterwards be unquestionably proved, I should, in that case, be persuaded that I had supernatural intelligence imparted to me.”