Turner visited Switzerland every Summer from 1841 to 1844. These trips conveniently took him through his beloved Germany and along the Rhine, from where he could detour to the Mosel and other areas. The watercolours he produced on these tours are amongst his most poetic responses to light, air and water in landscape. In simple pencil jottings and gestural, rapidly applied washes of colour Turner, here, conveys thick mists as they rise from a river valley to be burnt off by the early morning sun brightening behind a hill-top castle. This watercolour comes from a sketchbook that Turner put together himself, a practice he had begun on these late tours to compliment the various commercially produced sketchbooks he used. Constructed from larger sheets of paper that he cut down, the benefit was a closer control over his materials. Ever sensitive to the importance of paper and its preparation, the verso of this sheet has been washed with grey so that it would be ready to use when the right light and atmosphere presented itself. A report on this watercolour by Ian Warrell, and a report on the paper by Peter Bower are available on request. We are grateful to both for their help in cataloguing this watercolour.