Painters marry together shapes, tones, lines, marks, textures and, above all, colours, to create arrangements we then describe as compositions – just as composers of music do when arranging musical notes. The English Romantic painter JMW Turner was a virtuoso, particularly in colour, with all its glowing richness.
At the heart of his system was the studied placement of warm and cool colours next to and within each other. No painting better illustrates his use of colour than Venice: Looking across the Lagoon at Sunset. The sky is a warm panel of colour above a cool panel of water below. The glowing warmth of an evening sky is strengthened with a deeper warm at the lower left, while the cool blue of the sea is strengthened with a deeper cool…