' The Birth of Venus ' Nicolas Poussin (French 1594-1636) oil on canvas, circa 1635-36. Philadelphia Museum of Art, Philadelphia.

Although it is here entitled 'The Birth of Venus ' , the subject of this painting remains the subject of lively scholarly debate : some see her triumphal parade , and others see the sea god Neptune's marine procession. There is even disagreement as to whether Venus is depicted at all . The woman in the centre might instead be Galatea , a sea nymph who is often shown riding in a cockleshell chariot drawn by dolphins. As reflected here, Poussin exercised great skill into introducing multiple meanings and rich ambiguity into his paintings of classical themes. Sold to Catherine the Great of Russia in 1771, the painting was sold again from the Hermitage Museum in Leningrad ( now St Petersburg ) by a soviet government desperate for Western currency in 1932 , when it was acquired for the Philadelphia Museum of Art.