Details competition no 438

In which painting by which painter can you find this show?

Answers on a postcard, to arrive by Friday 25 June: DETAILS 438, IoS, 1 Canada Square, Canary Wharf, London E14 5DL. Three winners will each receive a bottle of champagne

Details 436 came from Stubbs' Racehorses belonging to the Duke of Richmond Exercising at Goodwood (1760-1). It's odd that Stubbs, who knew so much about horses, didn't know how their legs galloped, but maintained the traditional rocking-horse convention - as did nearly every artist, until rapid-exposure photography exposed the truth. But the convention is maybe not so much a factual mistake as a device, which has its own truth to motion, as this image in particular shows. Its ducks-up-the-wall trio of horsemen captures, not the look, but the bounding rhythm of a hard ride. The picture is in Goodwood House.The first three correct entries came from: A Falby-Clark, London N4; J Barker, Dorset; K Baclawski, Swansea