Further to my blog entry about subconsciously remembering, this may be another (slightly more famous) example.
In 1907 the current owner of the ruins of Glastonbury Abbey sold the land in an auction. The eventual winner was Mr Jardine, a Conservative MP, who planned to sell it on to the Church of England once they had raised the money (which they couldn't possibly have done in time for the auction).
Until that time, it had passed from owner to owner with varying amounts of care lavished upon it. Despite it's high standing in English culture, the ruins had not always been carefully preserved. A letter in the 1794 volume of The Gentleman's Magazine complains that stone from the ruins was being taken in order to repair the roads.
Once Mr Jardine had completed the purchase and it looked like only a matter of time before it passed into the hands of the CoE, a new series of archaeological digs was arranged for the site, and the architect Frederick Bligh Bond was put in charge. It was, by all accounts, very successful and in the Times in 1912 they list the findings of the dig.
What was most impressive were the discoveries of three chapels: Edgar's, Dunstan's and the Loretto Chapel (discovered in 1919, so not listed above) whose locations had eluded antiquarians until that date.
In 1919, just as the first traces of the Loretto Chapel had recently come to light, Frederick Bligh Bond held a public lecture in which he confirmed that the source of his information came from a series of psychic experiments, as detailed in his 1918 publication “The Gates of Remembrance” which describes a series of communications with deceased monks who'd lived in the Abbey. In these seances, he was assisted by Mr Bartlett, and their chosen method of communication was automatic writing. In this, the receiver holds a pen lightly on a piece of paper and, in a trance-like state, writes down messages from the departed.
But Messers Bond and Bartlett had both fully researched the history of Glastonbury Abbey, and H.J. Wilkins puts forth the theory that their communications were the result of subconsciously extrapolating guesses and theories based on the information they already knew. Wilkin's points out several obvious clues in previous texts placing the Edgar Chapel at the East end of the Abbey, which is where it was found.
Even the Loretto Chapel, which was barely mentioned in previous literature and is in some ways Bond's most impressive finding, was found in a place illustrated in an old sketch (and also the gardener of the Abbey grounds swore that a previous owner had taken stonework from the ground in that area for building work). Additionally, the spirits only suggested digging in this area after extensive digging along the whole north wall had found nothing. Basically, they said to look in the one place Bond hadn't looked yet.
Given the extensive research that both men had undertaken, and considering the fact that the psychic communications continued after the dig had begun and findings were coming to light, I do wonder if their knowledge of the subject matter was being subconsciously fed back to them through the medium (pardon the pun) of automatic writing.
Gentleman's Magazine, 1794, p305
"Glastonbury Abbey", The Times (London, England), Friday, Nov 22, 1912; pg. 10
Wilkins, H.J., “A Further Criticism of the Psychical Claims concerning Glastonbury Abbey and of the Recent Excavations”, J.W.Arrowsmith Ltd, Bristol, 1923
Bond, F.B., “The Gate of Remembrance”, B.H.Blackwell, Oxford, 1918