In 1718 and 1719 Braunstein and Le Blond made a large rectangular reservoir, twenty-nine metres wide and sixty metres long, in this area; it was called the Menagerie Pool; swans and other aquatic birds were kept here. Soon after this, the area was laid out as a formal garden. Between 1721 and 1724 a fountain was set up in the middle of the Menagerie Pool. Fifty years later Yakovlev and Velten turned the Petrine Menagerie Pool into a private royal bathing-place, shut in by high walls with painted decorations. In the middle of it was a cylindrical pedestal faced with tufa and edged with sixteen gilded lead dolphins, spouting jets of water from their mouths. The central jet was enclosed in a tin fluted pillar, crowned by a triple gilt disc with holes around the edge. A water-wheel was concealed in the pedestal, and when the fountain was started up, it began to revolve the pillar; jets of water spurted out like rays of sunlight from the disc, and thus the fountain came to be called the Sun Fountain.