French, 'The Sky at Sunrise', 1821

The glowing sky is set between dark hills and threatening storm clouds, the strip of dense grey clouds at the top echoing the blue silhouette of land at the bottom. Distinctive jigsaw-shaped clouds are depicted in layers white hovering over grey, blue sky beyond fading to rose and peach at the horizon.

The inscription at the bottom edge gives an exact date and time of 4 May 1821 at half past five. It must be 5.30 in the morning, and the sketch was evidently executed rapidly. In his influential treatise of 1800, Elémens de perspective pratique, Pierre-Henri de Valenciennes recommended that no longer than half an hour be spent when capturing such fluid light conditions. While this sketch has not yet been attributed to an individual artist, the inscription implies that the painter is French.