Andreas Achenbach certainly did not produce this small water study for sale, probably not even for the eyes of a public. But even as a sketch for his own use, the picture is unusual: Achenbach shows pure water, no banks, no proportions. Not even the colours - brown-red, greenish, white - are unsually associated with water. Achenbach looks at gentle waves and a transparency through which the ground shimmers. As a successful painter of seascapes and harbour views, here he created a close-up of the element that was fundamental to his work.