It is one of the oldest mysteries in book publishing - and also one of the most disreputable.
The anonymous authorship of My Secret Life, a Victorian pornographic epic which outstrips Casanova with its exhaustive detailing of sexual pleasures, has puzzled historians since it first appeared in the late nineteenth century.
The real identity of the wealthy diarist, who called himself 'Walter' and claimed to have slept with 1,200 working-class women over 40 years, has eluded detection, in spite of the fact that a well-known connoisseur of erotic photographs and an editor of The Times were among the list of suspects.
Now biographer Ian Gibson believes he has solved the riddle. His book, The Eroto-maniac , to be published early in the new year by Faber, will point the finger of suspicion firmly at one man - Henry Spencer Ashbee.
An acknowledged collector of pornography with a penchant for flagellation, Ashbee has drifted in and out of the frame since 1894, when six proofs of the manuscript of My Secret Life were printed in Amsterdam. Other putative authors of the frank 'narrative of amatory episodes' have included Edward Sellon, who wrote Annotations on the Secret Writings of the Hindus before killing himself in 1866; and John Walter, an editor of The Times . But Gibson, who has studied the riddle for 20 years, believes he has proved that Ashbee is the true author.
'Conceiving My Secret Life and writing it was exactly the sort of undertaking for which Ashbee was well suited,' writes Gibson, who has published definitive biographies of Salvador Dalí and Federico García Lorca.
Gibson has been intrigued by the anonymous work since he made a chance discovery in the British Library. He was researching his 1979 book, The English Vice: Beating, Sex and Shame in Victorian England , when he spotted a watermark on a page of the original manuscript of My Secret Life. It showed bees circling a honeypot.
'Bees! Ashbee! I thought. He could have chosen paper with a watermark that alluded to his name, thereby leaving a generous clue for researchers,' says Gibson.
Using new access to Ashbee's personal diaries and letters, he has found a match with the mysterious 'Walter', who once declared: 'Looking through diaries and memoranda, I find that I've had women of 27 different countries, and 80 or more different nationalities, including every one in Europe.'
The two share a love of Hamlet, a knowledge of the same parts of London and the same languages, and they both refer to John Cleland's Fanny Hill as the only convincing fictional erotica they have read. They use the same sentence structure and make the same spelling mistakes.
They also share early sexual experiences with a servant and a fascination with sexual freak shows.
Ashbee is known to have compiled a library of erotica and kept a diary throughout his life. Tellingly, his diary stops during the years 'Walter' kept his journal.
'Walter' supposedly arranged for the Belgian-born bookseller Augustin Brancart, then based in Amsterdam, to publish My Secret Life and Ashbee had a connection with Brancart too. Scholars, though, remain convinced that the whole work is a fake. Whatever the motive, there were at least 25 copies of the banned book in circulation at the turn of the last century and famous owners included Queen Victoria's great-grandson, the 2nd Marquess of Milford Haven.
Earlier this year a Channel 4 documentary told the story of Walter, narrator of the book. The programme argued that the book is increasingly regarded as a unique source of information about social conditions and morality in nineteenth-century England. The memoir has been at the centre of a series of legal censorship tussles over the years.
In 1969 John Mortimer, the barrister and novelist, defended a Bradford printer who was hoping to publish the book. But the prosecutor successfully branded the book 'utterly and totally obscene' and Mortimer lost the case. The printer, Arthur Dobson, received a two-year sentence, despite the testimony of academics who said the book was a valuable social document.