The Muséum Central des Arts (Central Museum of Arts) was opened in 1793 in the ‘Grande Galerie’ of the Louvre. But the gallery was dark and in 1798 the painter Hubert Robert, curator of the Museum, painted a visionary picture of the changes he wanted to make. It shows a glass roof supported at intervals by double marble columns and buttresses. Napoleon I’s personal architects, Charles Percier and Pierre Fontaine, took up this idea and had the vault pierced in places to let in daylight. They divided the gallery into nine bays with marble columns and arches.