Henri Rousseau - Tiger on a Tropical Storm (Surprised), 1891, 130 x 162 cm. Rousseau was a self-taught painter who was known as “le Douanier” (the customs officer) because he worked at a customs house and only painted in his spare time. This bold, richly colourful picture is carefully composed for dramatic effect. Windblown grasses and branches silhouette against the long streaks of lightning wriggling across the sky.