This is an example of the large, soft-backed 'roll' sketchbooks that Turner favoured so much during the 1840s. Their name derives from the ability to roll them up and keep them in a pocket. Turner would take several on tour, along with smaller books, to be used for fleeting observations and thumb-nail sketches. The larger books were for more carefully selected compositions, which might well be used as the basis of a finished work. Drawing was often undoubtedly undertaken on the spot, and colouring too on occasion, although while on tour Turner also worked up studies later in his lodgings.
Gallery label, September 2004