Backed by the Franco-American Union, the plan to build a monument commemorating the United States' independence started taking shape in the early 1870s. Sculptor Auguste Bartholdi designed an allegory of Liberty holding up a torch to enlighten the world. The spectacular work posed a towering technical challenge, but Gustave Eiffel rose to the occasion, designing an iron frame on which hammered copper plates would be affixed to form the statue. In order to ensure that the feat was technically feasible, Bartholdi started assembling the statue in the courtyard of the Gaget, Gauthier et Cie workshops in Paris in 1884. Then the artist had a brilliant idea for funding the project: he opened the worksite up to the public and charged admission to see it. Beguiled Parisians watched as the metal colossus rose above the city's rooftops. Then the statue was taken apart, packed in crates and shipped to New York, where it was reassembled and inaugurated in 1886. In 1907 Bartholdi's widow gave the museum this 1:16 painted plaster model standing on an ornately decorated base enclosing a small diorama.