His early work used soldered and welded metal as well as junk materials, and by 1960 César was considered one of France's leading sculptors. In that year, on a visit to a scrap merchant in search of metal, he saw a hydraulic crushing machine in operation, and decided to experiment with it in his sculpture. He astonished his followers by showing three crushed cars at a Paris exhibition. It was for these 'Compressions' that César became renowned. César selected particular cars for crushing, mixing elements from differently coloured vehicles. In this way he could control the surface pattern and colour scheme of the piece.
