One of the group of late 'unfinished' oils based on Liber Studiorum subjects, in this case R.18, published 29 March 1809 and classified as 'E.P.' (?Epic Pastoral). Turner had already treated the subject in a watercolour exhibited in 1802 with the sub-title 'Noon' and a reference to Akenside's Hymn to the Naiads (Walker Art Gallery, Liverpool). Akenside saw the Naiads as allegorical deities, symbolising the interaction of sun and running water in 'giving motion to the air, and exciting summer breezes'. This late painting was, in its prismatic colouring, much more effective as an allegory about the forces of nature than the early versions (see Gage 1969, pp.144-5, and exhibition catalogue, Landscape in Britain, Tate Gallery, 1973-4, No.218).

Turner's use of watercolour on this canvas can be seen in the little droplets where the oil paint has rejected total assimilation. The paint surface also shows vertical cracking from rolling, typical of most if not all of this group of 'unfinished' oils that have escaped the Turner Bequest. For the possible early history of these works see No.620. The first known owner of this picture was the Rev. Thomas Prater in 1871.