Untitled (1935) is representative of Calder's floor- and pedestal-based mobiles made in the early 1930s. Here, Calder uses wood, a material that had been absent from his work since the previous decade, in combination with wire and string. Five painted wood orbs, varying in size, are organized in a spatial arrangement of counterbalance and organic movement. Calder later referred to these works as "Universes." For much of the 1930s and like other artists engaged with abstraction after World War I, Calder used cosmic descriptions and scientific terminology: "I felt that there was no better model for me. . . . Spheres of different sizes, densities, colors, and volumes, floating in space, traversing clouds . . . currents of air, viscosities and odors—of the greatest variety and disparity."1 An imagined solar system, the work is an antecedent of Calder's large, independently hanging mobiles, in which finer, less visible wires anchored to the ceiling would replace Untitled's earthbound wooden base, inverted L-shaped support, and restricted movement.