A leading exponent of kinetic art, Alexander Calder revolutionized sculpture by creating suspended abstract forms that were named “mobiles” by the artist Marcel Duchamp. Describing them as “detached bodies floating in space,” Calder produced works that are perpetually in motion, through a system of weights and counterbalances, as they move in response to subtle air currents. Embracing the rhythms of modern life, Calder’s Streetcar transforms a noisy mode of urban transportation into a restrained, slowed composition of biomorphic shapes made from industrial materials.