Jean-Auguste-Dominique Ingres

Ingres thought of himself as the last honest man in French painting, the guardian of drawing and clean contour and Raphael's example, against a younger generation he saw as smearing colour around and calling it art. That generation had a leader, Eugene Delacroix, and for decades the Paris art world split into two camps: the party of line behind Ingres and the party of colour behind Delacroix. Ingres called his rival the apostle of ugliness, and at the 1855 world's fair in Paris the organisers reportedly had to hang the two men in separate rooms.

He had earned the right to be dogmatic. Trained in the studio of Jacques-Louis David, the great painter of the Revolution and of Napoleon, Ingres drew with a precision almost nobody could match. And yet his most famous picture breaks every rule he preached. The Grande Odalisque of 1814, a reclining harem woman painted for Napoleon's sister, has a back stretched by two or three vertebrae too many and a pelvis that could not physically exist. Critics howled that he had forgotten his anatomy; he had done it on purpose, lengthening the body for the long, cool, unbroken line he loved more than correctness.

There is a smaller thing he is remembered for. From boyhood Ingres played the violin, well enough as a teenager to sit in the orchestra of the opera in Toulouse, and he kept a fiddle beside his easel his whole life. The habit gave the French language a phrase, un violon d'Ingres, for the serious hobby a person keeps alongside their real work. In 1924 the photographer Man Ray took the phrase for a picture of his own, painting the two curved sound-holes of a violin onto a model's bare back.