This is one of the finest finished compositional studies in pen and wash by Pietro da Cortona (1597-1669). The figures and landscape were drawn initially in black chalk, pen and ink were later used to define the final outlines. Light and shade were added with white heightening and grey-brown wash.The story is mainly based on the Argonautica of Apollonius of Rhodes. On the right, Medea assists Jason to remove the Golden Fleece from the branches of the tree while beneath lies the sleeping dragon. According to a rarer account in the Argonautica of Orpheus, the god Orpheus, summoned the god of sleep to work his spells on the dragon, by playing his musical instrument. Far left in the background is the Argo, the ship which brought Jason and his companions to Colchis. In the centre are two of Jason's Argonauts with a priest from the Temple of Mars in whose sacred grove of trees the Fleece was kept.The drawing was presumably made for a cardinal from the Borghese family, possibly Cardinal Scipione Borghese (1576-1633), as the family's coat-of-arms is visible in black chalk on the ground. The upper half of the shield, topped by a cardinal's crown, shows a crowned eagle with outspread wings. Medea puts her foot on the plain band in the centre and the dragon itself provides the lower half of the shield. It was engraved by Charles Audran in 1658 for another patron as the outlines are indented for transfer.