Among the casualties were examples by Henri Matisse, Edgar Degas, Kurt Schwitters, Jean Pougny and Egon Schiele.

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In Kurt Schwitters's mischievous Dadaist collage of 1921, a wheel covers the cherubs and Mary becomes a Louise Brooks lookalike with short hair and modern hat.

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Schwitters was an undistinguished figurative painter until 1917 when, under the experimental influence of the Cubists and Expressionists, he developed what he called his Merz-paintings and poems.

ECONOMIST: Kurt Schwitters

Schwitters made lively connections across Europe with Dadaists and later with Constructivists (whose architectonic art, which much influenced his Hanover Merzbau, is much cooler and more rational than Dada), promoting their work in his Merz magazines.

ECONOMIST: Kurt Schwitters

The Merzbarn in the Lake District was made at a desperate time in his life, when Schwitters found himself subsisting, with a serious heart condition, in dank English lodgings on the proceeds of academic portraits and landscapes, despondent that he could not even obtain an interview with the director of the National Gallery in London.

ECONOMIST: Kurt Schwitters