Scientific examination of Leonardo’s Virgin of the rocks, at the National Gallery, has revealed two underdrawings—confirming the authenticity of this sometimes disputed work and helping to explain its lengthy gestation. Two years ago the Metropolitan Museum of Art’s specialist Carmen Bambach suggested that the London painting was a copy by Giovan Ambrogio De’Predis of the Louvre’s original version.
The infra-red examination of the National Gallery’s painting shows that the first underdrawing was of a similar subject, but quite different in composition. Curator Luke Syson and conservator Rachel Billinge, whose study is published in the July issue of The Burlington Magazine, conclude that it is “entirely autograph” and datable to around 1493.
Leonardo later abandoned the original design, covering it with a light-grey priming layer. He made a second underdrawing, which is close to the final composition. Mr Syson and Ms Billinge point out that the second underdrawing is “sketchy and spontaneous in some parts, rigorously controlled in others, superbly confident throughout”.
Why then did Leonardo do a second underdrawing, to finish the picture in 1508? The authors speculate that it may have been the Confraternity of the Immaculate Conception in Milan which “demanded a copy of his first, miraculous work [the Louvre painting], rather than the original composition”.