FOR years I have dined out on a piece of gossip about the late Duchess of Windsor which was so outrageous that mouths fell open in amazement, before the table companions would dismiss it on the grounds that, surely, it could not be true.

Though I began to doubt it myself, I never forgot the circumstances in which I gathered this sensational story.

Researching the biography of Scots novelist Alistair MacLean, I was staying with Count Giovanni Volpi at his palace on the Grand Canal of Venice, trying to find out why he had owned the film rights of HMS Ulysses for more than 20 years without making the film.

That was a story in itself. But as we discussed it in the study of the man whose father founded the Venice Film Festival in 1932, the rather brusque Count Volpi suddenly announced that we were due for cocktails at a friend's place.

He wasn't the kind of man to furnish you with advance information. I simply followed him to the palace doors, from which his speedboat whisked us up the canal to some narrow back streets which opened out to a grand square.

Approaching the large door of what looked like a cathedral, Count Volpi and I were received by a flunkey who led us up the broad stone staircase, complete with its red carpet.

Still baffled by the grandeur, I came to realise that this was no more than a dwelling-house, albeit the grand home of one of the Merchants of Venice (yes, they still exist), and that our hostess was just having a few guests for supper.

More at home in the farmyards of Aberdeenshire, I set about the cultural adjustment and tried to figure out this cosmopolitan gathering. There was a hard core of Venetian wealth, the inevitable German professor - and the obligatory visiting lady from America.

After a few glasses of Italy's best, it was this last-mentioned whose nasal drawl suddenly quietened to the confidential as she unfolded, for my personal benefit, the strange story about the Duchess of Windsor.

The American had a lady friend who was driving on the outskirts of Paris one night, not far from the Windsor home, when she came upon an older woman in some distress because her car had broken down.

She stopped to help and was showered with such gratitude that she accepted an invitation back to the house.

The lady in distress turned out to have been a nurse to the Duchess of Windsor and the substance of her remarkable claim, given in confidence of course, was that the Duchess was really a man.

Never! Yes. In the later years, it had been the lady's regular task to bath the Duchess and, without being too specific, she was certainly not a woman. This poor dear was tired of bottling up the information.

Well, that was the story I carried for years, good enough for the dinner-table but not the kind of intelligence to spread too widely without more evidence.

Matters changed the other day, however, when Michael Bloch brought out his book, The Duchess of Windsor, in which he presents a strong case for the fact that, because of physical peculiarities, the former Wallis Simpson was incapable of sexual intercourse and may well have died a virgin.

Far from being a sensation-seeker, Mr Bloch is in fact the man engaged by the Duchess's lawyers in Paris to edit the Windsor papers. As he approached the task, he was evidently told by the late Dr John Randell, consultant psychiatrist at Charing Cross Hospital and an authority on sexual matters, to keep in mind that Wallis Simpson was really a man. Dr Randell was given the details by a colleague who examined her.

Bloch's subsequent inquiries revealed that her likely condition was Androgen Insensitivity Syndrome, commonly known as AIS, though he doesn't claim independent proof of it. Roughly speaking, AIS children are born genetically male but develop outwardly as female.

Though they can be sexually attractive - their number includes fashion models - the reproductive organs don't exist. (Some historians now believe Queen Elizabeth I was the same.)

It would explain a lot about the Duke and Duchess of Windsor, whose romance of 60 years ago rocked the monarchy and led to the Duke's abdication after he succeeded his father as King Edward VIII in 1936.

He always denied indignantly that the American Wallis Simpson was his mistress before marriage. It now seems possible there wasn't intercourse even after marriage.

For a start, she was named Wallis after her father, indicating some confusion at birth.

Another recent book, Dynasty by Donald Spoto, reported that, on the eve of her wedding to the Duke, the Duchess told her closest male friend, Herman Rogers, that she had never had intercourse with either of her first two husbands.

Her French lady lawyer, Suzanne Blum, was also convinced that her client remained a virgin. And her life-long butler believed her intimacies did not go beyond an embrace.

As for the Duke of Windsor, it would seem that, for his own peculiar reasons, he loved the idea of her dominant role.

So my tale from the home of a Merchant of Venice seems to have credibility after all. It's not the kind of story you might normally expect of a Monday morning but I thought you might be interested. Shakespeare certainly would have been.