Between 1827 and 1832 major alterations were made to the Palais Bourbon to transform it into the Chamber of Deputies. Dismantling its Corinthian capitals and other decorative elements proved particularly difficult, so the architect and engineer Charles Eck devised a machine to facilitate their removal. When his invention was shown as a scale model at the Exhibition of Products of French Industry in 1834, it was awarded a bronze medal and acquired by the Conservatoire. The machine has an armature designed to clasp the mass of stone without touching its sculpted sides. Metal struts are slid beneath the block to be dismantled and four pressure screws are tightened from above to maintain it in place so that the capital can be removed by normal methods such as cranes or derricks. The lifting method in use here, a breast derrick (an A-framed mast supported by guy ropes) was widely used in the 19th century but has long since been superseded.