Ruskin is probably referring to the Campo Santo, Venice (oil on canvas, exhibited Royal Academy 1842, Toledo Museum of Art, Ohio, Wilton P397), where the boats' sails are given lengthened reflections.
J.M.W. Turner 1775-1851
Campo Santo, Venice 1842
Oil on canvas, 62.2x92.7cm
Exhibitions: RA 1842 (73)
Engraving:
Engraved by J. C. Armytage, 1899
Steel engraving, size unknown
Engraved for the Art Journal
Provenance: Bt. Elhanan Bicknell at RA, 1842; sale Christie 25/4/1863 (112), bt. Agnew for Henry McConnell; sale Christie 27/3/1886 (76), bt. S. White for Mrs. J.M. Keiller of Dundee; acquired from Keiller, 1916, by Edward Drummond Libby through Henry Reinherdt and Son; presented to the museum by Libby, 1926
Collection: Toledo Museum of Art, Toledo, Ohio, USA
For a reproduction of this artistic work, please consult: Stainton, Lindsay, Turner's Venice, (British Museum Publications, 1985), pl.102