Mention Surrealism and the chances are you'll think of Salvador Dali with his preposterous waxed moustache and virtuoso paintings of melting clocks and grotesque metamorphoses. The clocks made their debut in The Persistence of Memory (1931), probably his most famous painting. He wasn't the first or by any means the best Surrealist, but he's the one who captured the public imagination, and his genius for self-promotion made him one of the century's most famous artists.