Answers on a postcard, to arrive by Friday 9 July: DETAILS 440, IoS, 1 Canada Square, Canary Wharf, London E14 5DL. Three winners will each receive a bottle of champagne
Details 438 came from Lawrence Alma-Tadema's Phidias Showing the Frieze of the Parthenon to his Friends (1868). The picture combines several of the artist's special interests: the ancient world caught off-duty, accurate archeological reconstruction, interestingly angled views. The scene is set on scaffolding, offering below-floor perspectives. The marbles are authentically coloured. And - with the great sculptor acting nobly modest - here's a founding monument of Western civilisation seen at its private view. There's just one touch of inauthenticity. It's a private view, but some of the invited are clearly looking at the work. The picture is in the Birmingham Museum and Art Gallery.
The first three correct entries came from: P Cousins, St Helens; I Jones, Helsby; and S Strong, Gloucestershire.