American art historian. For most of his career he was associated with Yale University, where he studied (BA, 1932; MA, 1934; PhD, 1942) and then taught from 1936 to 1966 (he was appointed a professor in 1956). During this time he was also a curator of modern art at Yale University Art Gallery. From 1966 to 1977 he was director of the Sterling and Francine Art Institute in Williamstown, Massachusetts, and from 1966 to 1975 professor of art at its sister institution, Williams College, Williamstown. His best-known book is Painting and Sculpture in Europe 1880–1940 (1967) in the Pelican History of Art series. This is an authoritative and readable introduction to its subject and has been revised and reprinted several times, although it is now dated in its approach and the serious student needs to complement it with more recent literature. He was a friend of Marcel Duchamp and translated works by and about him.