I have gone back to some things that can't possibly be done: water, with weeds waving at the bottom. It is a wonderful sight, but it drives one to crazy to try to paint it. But that is the kind of thing I am always a tackling.

In Monet's letter to art critic and his friend Gustave Geffroy, 22 June 1890; as quoted in Letters of the great artists – from Blake to Pollock, Richard Friedenthal, Thames and Hudson, London, 1963, p. 129 - 1890–1900