A rapid oil study of clouds over London by British artist David Cox, dated 1847. This sketch captures atmospheric light and movement through expressive brushwork.

David Cox was a leading figure of the Birmingham School and a prominent member of the Society of Painters in Water Colours. While he is best known for his watercolours, his later career saw an increased use of oil paint. This study, dated 31 May 1847 in London, captures a specific meteorological moment. It demonstrates his interest in the atmospheric effects of the English sky. The artist frequently travelled between London and North Wales, recording the changing weather conditions he encountered. The composition focuses entirely on the formation of clouds against a blue sky. Cox uses broad, rapid brushstrokes to suggest movement and light. Dark, heavy masses of grey and charcoal occupy the centre of the frame. These are contrasted with bright white highlights where the sun hits the upper edges of the clouds. Touches of ochre and pale yellow suggest the warmth of the sun filtering through the vapour. The blue of the sky varies from a deep cerulean at the top to a paler, hazy tone near the horizon line. This gradient adds a sense of depth to the subject matter. Cox often worked outdoors to record direct observations of nature. This piece is a working sketch rather than a finished exhibition painting. It shows the artist's technical transition towards a looser, more expressive style. The visible texture of the paint and the speed of execution anticipate later developments in plein air painting. The inscription at the bottom left provides a precise record of the time and place of its creation. It reflects the 19th-century scientific interest in cloud classification and weather patterns.