Sulman, “A Memorable Art Class”, 550
Like the later drawing of Jan Van Eyck's Studio, we know about this sketch from Thomas Sulman's report of DGR in his art class: “One day Rossetti scribbled in ink on the back of a letter a motive for a picture, two lovers embracing in a turret of a castle wall. The subject pleased him and he blotted in a scheme of colour. Both figures wore red. The wall against which they stood was red also. Red also was the woman's hair. The fields beyond were vivid green and the sky blue... He painted it later on, but never so well as in the rude, letter-paper sketch”.