The Leonardo hidden from Hitler in case it gave him magic powers

One of the world's most famous self-portraits is going on rare public display in the northern Italian city of Turin. Very little is known about the 500-year-old, fragile, fading red chalk drawing of Leonardo da Vinci but some believe it has mystical powers.

There is a myth in Turin that the gaze of Leonardo da Vinci in this self-portrait is so intense that those who observe it are imbued with great strength.

Some say it was this magical power, not the cultural and economic value of the drawing, that led to it being secretly moved from Turin and taken to Rome during World War Two - heaven forbid it should ever fall into Hitler's hands and give him more power.

Whatever the reason, this was the only work from the entire collection of precious drawings and manuscripts to be removed from the Royal Library in Turin at the time.

The library's current director, Giovanni Saccani, says nobody even knows exactly where it was hidden. "To prevent the Nazis from taking it, an intelligence operation saw it transported in absolute anonymity to Rome."

Under such difficult circumstances, preservation was not properly considered, "nor did they have the same knowledge and techniques back then," says Saccani. "Naturally, this did not do its condition any good."

Inside the Royal Library a pristine red carpet lines the stairs - we follow the steps down to a secure underground vault with reinforced doors.

This purpose built caveau has been the home of Leonard's Self-Portrait, and thousands of other priceless drawings and manuscripts, since 1998. The picture's treatment today could not contrast more strikingly with the neglect it suffered during the first half of the 20th Century.

The lighting is exclusively fibre optic - no natural light can enter this room - and the temperature is kept at a constant 20 degrees Celsius, the humidity at 55 per cent. The display cases are made of a type of glass which Saccani describes as "anti-everything", and the whole area is fitted with alarms and security cameras.

Using a special preservation torch, Saccani shines some light onto the drawing's surface to demonstrate the extent of the damage known as foxing, when small reddish-brown spots or marks appear on ancient paper.

"This case is particularly bad," he sighs - 200 years ago the foxing was less obvious. "On the bottom left of the drawing there was a red chalk inscription in Latin which said Leonardus Vincius, which has now completely disappeared."

Since the damage is so extensive and the paper so fragile, restoration would be extremely complex. Exhaustive analysis and discussion by world experts in restoration has led to "the decision to maintain the status quo," says Saccani.

And since coming to the caveau in 1998, the condition of the drawing has not deteriorated any further.

Leonardo's Codex on the Flight of Birds is also on display at the exhibition

"This comforts us because we know we are getting it right now. You have to remember it's a good 500 years old. The pictures we drew at school probably don't exist anymore and this was a drawing done on ordinary paper, so I think it's pretty extraordinary that we can still display such a masterpiece today."

Equally extraordinary is the story of how this self-portrait ended up in Turin. It was part of a vast collection purchased in 1839 by King Carlo Alberto of Savoy. A passionate collector, he bought it from Giovanni Volpato, an art dealer and curator who had travelled extensively throughout Europe. How he came upon Leonardo's drawings is a mystery but it is known that he asked the king for the sum of 70,000 Piedmontese lire for the collection.

"A doctor earned 1,000 lire a year at the time so it was an astronomical figure," smiles Saccani. "The king managed to get him down to 50,000 but it still took him eight years to pay for it in instalments."

But Saccani says Volpato was not the ruthless businessman he might sound.

"Volpato's aim wasn't simply financial because, in exchange for agreeing to give the king a discount, he asked to be allowed to become the unpaid curator of drawings in the Royal Library."

And since then Turin has remained the home of the red chalk Self-Portrait.

Is it really a self-portrait?

Generally dated around 1515, some experts believe the picture corresponds more with Leonardo's style in the 1490s, yet the subject of the drawing is an old man.

"He wasn't terribly keen on the idea of self-portraiture full stop," says James Hall, author of The Self-Portrait: a Cultural History - he doesn't believe the portrait was drawn by Leonardo. "He didn't much like the idea that the art work should be a portrayal of the artist. He wanted the art work to represent an ideal."

Hall thinks this drawing has become famous at least partly because of the sheer lack of self-portraits by Leonardo. "People have latched onto this like the philosopher's stone and clung to it."

But others are less sceptical. "I'm quite happy to believe it is a self-portrait but I think it's for each person to decide when they see the real object," says Liz Rideal, the author of two books on self-portraits and a lecturer at the National Portrait Gallery in London and Slade School of Fine Art.

She says most people want to believe it is a genuine Leonardo "because he has this superman status… I think we are in awe of genius and therefore, if this is the self-portrait of a genius, then we want to see what he looked like."

As director of the Royal Library, Giovanni Saccani is in no doubt: "It is a self-portrait… anyone who finds themselves standing in front of this drawing is struck dumb. The first thing they say when they recover is 'this is giving me the shivers'. The expressive power of this face is absolutely connected to an emotion and an ability that only Leonardo could possess."

Leonardo's Self-Portrait is considered so valuable that it is subject to a state decree of immovability.

It can only be moved with ministerial permission. In 2011 it was taken to the Reggia di Venaria Reale just outside Turin for an exhibition marking the 150th anniversary of the unification of Italy.

"Transportation involved a special 'clima box' able to maintain the same air conditioning systems present here in the caveau," says Saccani. "This 'clima box' was then put inside a case, which was in turn placed in an outer casing, all of which was able to avoid vibration." The package was then driven with an armed escort and constantly monitored using remote technology.

An extraordinarily complex, delicate and expensive undertaking, unlikely to be repeated very often in the future.

Leonardo's Portrait of a Girl is on display as part of the King's Treasures exhibition

Over the coming weeks, 50 people will be allowed into the Royal Library's caveau every hour from 09:00 to 18:00 to see the self-portrait - the temperature of the vault has been lowered slightly to compensate for the body heat that people will give off.

Although there are more than 80 masterpieces on display in the King's Treasures exhibition - including further works by Leonardo, Raphael, Rembrandt, Perugino and Van Dyck - for most visitors, the highlight will be the rare chance to behold the face of the great Renaissance polymath.

And they might also bear one final myth in mind - it is said that just before taking an exam, students would do their last-minute revision in the Royal Library above the vault. Legend has it that studying near Leonardo's genius can somehow rub off.

Photographs courtesy of the Regional Management for the cultural and landscape heritage of Piedmont

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