卡西斯，隆巴尔角，作品196号

Paul Signac gave this painting an opus number, like a composer, and that tells you how he thought about it. In 1889 he and his friend Georges Seurat were the leaders of a new, deliberately scientific kind of painting. They set pure dots of unmixed colour side by side and let the eye do the blending, and Signac had been reading the theories of Charles Henry, a scientist who claimed that particular lines and colours carried measurable feeling. That summer Signac sailed down to Cassis, a small fishing port near Marseille, and painted the light there in five canvases. This is one of them, the headland called Cap Lombard, built almost entirely from just two opposites, blue and orange. The curve of the coast and the rocks resolve into a calm arrangement of triangles, every wave and cliff laid down dot by patient dot.