Last week's detail came from Camille Corot's Chartres Cathedral. The story is that Corot originally painted this picture in 1830, and let it go; but then came across it again 40 years later, and considered it too photographic - photography having been invented in the meantime - and retouched it more atmospherically. It's in the Louvre.
The first three correct entries drawn were from: Mark Yakoushkin, of Charlbury, Oxfordshire; C J Parsons, of Almondbury, West Yorkshire; and D R Carter, of Lytham St Anne's, Lancashire.
Each will receive a bottle of champagne, as will this week's winners. Answers, on a postcard please, to DETAILS 174, The Independent on Sunday, 40 City Road, London EC88 1HP.