"While aesthetics generated by movement can be traced back to ancient wind chimes, the beginning of kinetic art is associated with avant-garde experimentation of the early twentieth century. The generally acknowledged starting point is Naum Gabo’s 1920 publication of the realist manifesto and his exhibition of Virtual Kinetic Volume in the same year. Kinetic art explicitly introduced the temporal dimension into art, and movement was incorporated into works hung and framed as conventional paintings, freestanding sculpture both in and outside the gallery, machine works, and installations at a range of scales. With Alexander Calder’s exhibition of mobiles in Paris and New York in 1932, the genre received heightened exposure. He dominated the pre-war period with a series of developments on the mobile theme, while the most prolific period for kinetic art was during the 1950s and 1960s. In addition to the continuing popularity of Calder, prominent artists include Schoeffer, , Len Lye and George Rickey."