A painting that had lain unrecognised for around 150 years has been identified as the work of Italian artist Canaletto and valued at £2m, gallery chiefs said yesterday.
The work was identified by Sir Timothy Clifford, director of the National Galleries of Scotland, after the painting was extensive cleaned. It was given to the National Galleries as part of the establishing collection in 1850. The picture, which shows gondoliers and sailors at work in 18th century Venice, was identified at the time as a Canaletto copy by an imitator or student of the artist, and had been valued at no more than £5,000.
But following a lengthy cleaning which removed a blue wash that had been applied later to the original skyline, the signature of Canaletto was revealed.
Sir Timothy said the true value of the work, known as Grand Canal, Venice, was discovered several years after the cleaning but it was decided to research the matter further before releasing the news.
He told the Sunday Times: "This picture came from a very distinguished bequest and was always thought to be an inferior workshop paining - in other words, a pastiche in the style of Canaletto.
"From a copy worth £5,000, we have a painting worth £2m, which is very useful indeed for the National Galleries."
Born in 1697, Canaletto, or Giovanni Antonio Canal, is best known today for his romanticised versions of landscapes and urban settings. The churches and canals of Venice were a frequent subject.
The record price for one of his works is more than £10m, paid by Lord Lloyd-Webber in 1992 for a painting of the Horse Guards in London.
The discovery is one of a series of important finds by Sir Timothy, who is one of Britain's leading art experts.
Earlier this year, it emerged the curator had discovered a drawing by Michelangelo in the back room of a museum in New York during a research sabbatical.
Delighted museum officials in Scotland said there were no plans to sell the Canaletto, which is part of the permanent display at the National Gallery on Edinburgh's Mound.