A drawing of a castle and outbuildings in an enclosed bay. A thunderstorm above is showering torrents of water. Among the loops of rain are curious casts of drapery. The wooded hills to the left of the bay seem unaffected by the storm. The depiction of cataclysmic storms was one of Leonardo’s favourite subjects during the last decade of his life. He drew and wrote with relish about the futile struggles of man against the forces of nature. In this drawing black chalk is used to depict swirling, tempestuous storm clouds, while detailed sections of pen and ink on the lower part of the sheet show great torrents of water overwhelming the buildings of a castle.