Gamma

Alexander Calder made this hanging mobile in 1947 from sheet metal, wire, and paint. "Gamma" dates to what art historians call Calder's classical period, when his mobiles reached their most refined balance of form and movement. The shapes hang from delicate wire arms that shift with the slightest air current, creating constantly changing compositions. Marcel Duchamp coined the term "mobile" for these kinetic sculptures in 1931, while Jean Arp called Calder's stationary works "stabiles."

Calder (1898-1976) came from a family of sculptors but trained as a mechanical engineer at Stevens Institute of Technology before turning to art. That engineering background shows in how precisely his mobiles balance. During World War II, aluminum shortages pushed him toward carved wood, but after the war he returned to metal with renewed energy. "Gamma" is part of the Shirley Family Calder Collection at the Seattle Art Museum, one of the most important private Calder holdings in the country.