Strike a pose: infrared scans reveal the method in Munch’s Madonna

Preparatory sketch discovered beneath Norwegian master's painting shows how he struggled with the original composition

It is one of art history's most evocative female forms, a painting of a nude woman arching her back sensually, one arm behind her head and the other behind her back. Now a preparatory drawing has been discovered beneath Edvard Munch's Madonna in the National Museum of Norway, revealing that the Norwegian master struggled over how he should place her arms, initially showing them just hanging down, until inspiration came to him.

The underdrawing also shows that this masterpiece is likely to have been the first of five painted versions that Munch created in the 1890s.