For decades generations of Cambridge undergraduates have fantasised about a secret stash of Victorian pornography in the university's library tower.
Many have tried to gain access to the chamber to uncover its illicit secrets. So intrigued was Stephen Fry by the collection that he wrote about it in his first novel, The Liar.
Despite the brilliant scientists, spies and politicians that the university has produced, no student is believed to have gained access to the closely-guarded hideaway.
According to the university's authorities, the 17 floors of the 157ft-high tower contain nothing more racy than books with titles such as The Lover's Guide to Courtship (Illustrated).
Vanessa Lacey, the manager of the Cambridge University Library Tower Project, said: "The traditional student rumour is that the contents of the tower are pornographic.
"In fact we now know it to be a treasure trove for people who want to know more about Victorian society, and among the books are these late 19th and early 20th century lifestyle guides designed to teach young couples the art of courting. At the time they were acquired, they were not considered the sort of thing that serious students should be reading, so they were put away.
"Many of the 200,000 books in the tower have barely been read and some were never opened, but now they give us a fascinating insight into the life and society of the time."
The university has made the disclosure because it is in the process of putting all the titles online.
The books - likely to be of interest to historians rather than excitable students - that have been unearthed include A Golden Guide To Matrimony (1882).
It advises: "It should be the young man's duty to make the first overtures towards a closer relationship than that of mere friendship.
"Young women cannot be too reserved in this respect. Prudence is of the highest importance."
Other titles include Flirting Made Easy and Courtship And Marriage, which sensibly warns: "The young man who marries not, except in a few exceptional cases arising out of ill health, deformity, malformation, or great perversity of temper, or eccentricity of character, fails in one of the most palpable duties of life."
Students of pornography can take heart, however, because more recent erotica is kept there thanks to its copyright library status.
Mrs Lacey said: "There's plenty of pornography in the library which is more recent.
"People can come and have a look at it - for their research. But there's nothing terribly racy from the 19th century. What we found is the Mills and Boon of the era."
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