A bestselling novelist believes that he has solved Edgar Allan Poe’s final mystery – the cause of the writer’s early death.

Matthew Pearl, whose literary thriller The Dante Club became an international bestseller, said that he had chanced on the clues in 19th-century newspaper clippings while researching his second book, The Poe Shadow, which came out last year.

He realised the significance of his find only after repeated questions about Poe’s death at book-signings. “I really do think that, even in a mystery like this that you will never finalise, we are getting closer to the truth,” he told The Times. James Hutchisson, Poe’s most recent biographer, said: “It’s certainly the most hard-core factual evidence we have had.”

Poe died aged 40 in 1849 after being found delirious on the streets of Baltimore. Many argue that he died from drink, some claim that he was poisoned by political operatives, while others say that he committed suicide. Pearl believes he has evidence that Poe died a rather less romantic death from a brain tumour. The author’s quest is apt because Poe created the popular genre of the detective story with The Murders in the Rue Morgue, which features the first fictional detective, Augustin C. Dupin.

Pearl said: “When I started, I began to notice that, because there had been so much repetition and recycling of theories and people assumed, as I did, there was nothing new to find, they did not find anything new.”

Spurred by the questions at his book-signings, he reread old newspaper accounts of Poe’s coffin, which was moved 26 years after Poe died to a more prominent plot when interest in his work boomed. A letter to the Baltimore Gazette said a “medical gentleman” had found that Poe’s brain “was in an almost perfect state of preservation. The cerebral mass, as seen through the base of the skull, evidenced no signs of disintegration . . . though, of course, it is somewhat diminished in size.”

In a report in the St Louis Republican, a sexton at the graveyard said that on picking up Poe’s skull the “brain rattled around inside just like a lump of mud”.

Pearl, who lives at Cambridge, Massachusetts, consulted a pathologist, who said the descriptions indicated that Poe’s brain had calcified after death. The likely explanation for this was a brain tumour. Pearl said: “The [witnesses] saw something organic and brain-like in his skull rattling around that was dark in colour but smaller than the brain of a living person. Because the brain starts liquefying almost immediately and this was 25 years later, it has to be something other than the brain. It’s either something completely different or a growth that has calcified.” Professor Hutchisson reached the same conclusion after reading the hospital description of the cause of death – congestion of the brain. “He [Poe] himself thought there was something wrong. He called it ‘brain fever’.”

Hal Poe, a descendant of the author, said: “Often stories about Poe appeared for the first time years after he died and were not reliable. But in this case you have several different people referring to the state of the brain.” Interview with Kate Mosse, Books

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