George Rickey, American sculptor (born June 6, 1907, South Bend, Ind.—died July 17, 2002, St. Paul, Minn.), fashioned mobile geometric forms and claimed that movement was his main medium. With a combination of engineered exactness and visual minimalism, he created nonmotorized stainless-steel forms that, fueled only by gravitation and natural wind patterns, teetered between equilibrium and motion. These slow-moving changeable displays were often composed of planes of bladelike forms anchored to centre posts. Rickey was educated in humanities and art at Trinity College, Glenalmond, Scot., where his father, an engineer, had been relocated. Rickey also attended the University of Oxford and extended his art studies in Paris (where he began an apprenticeship). The first solo exhibition of his paintings was mounted in New York City in 1933. With brief interruption for service in World War II, he taught widely at various universities. In the late 1940s, while studying at the Chicago Institute of Design (later the Illinois Institute of Technology) and teaching at Indiana University, he switched his focus from painting to kinetic sculptural art. In the 1960s he relocated to East Chatham, N.Y., and quit teaching. By this time he was earning comparisons to Alexander Calder, as well as growing acclaim, particularly in Europe. In 1967 he published Constructivism: Origins and Evolution. In the 1970s his forms began to follow conical patterns along a fixed path, not just through planar motion, and later he experimented with separate moving elements, jointed together. Throughout his life he traveled widely, and he began producing increasingly larger, complex works, culminating with a nearly 17.5-m (about 57-ft) sculpture that was installed at the Hyogo Prefectural Museum of Art in Kobe, Japan, in March 2002.