Ferrari made his first wire-based sculpture in 1961. He began by knotting or securing the wires with washers and later employed soldering. Tower of Babel is one of his emblematic works from the 1960s. It evokes an edifice, perhaps an imaginary jail for the military, according to notes in his sketchbooks, with crumpled sheets of copper and bronze inserted in the body of the wire column. Ferrari continued making wire sculptures during his exile in Brazil in the 1980s, turning them into musical instruments or, as he calls them, ‘artefacts for drawing sounds’.