Dome

View showing one of four grotesque faucet (spout); The expenses for the fountain in Piazza Campitelli were partly paid by four families, owners of palaces that stand in the same square, or next to it, namely the Capizucchi, the Ricca, the Albertoni and the Muti. Being a work by della Porta, its shape followed the architect's usual scheme: a round basin, a central baluster, a larger basin below, and a stand. In this case the lower basin is octagonal, with alternate straight and concave sides, decorated with two grotesque faces (one of them has donkey ears), and the crests of the four families whose funds the fountain had been built with. Its large base, octagonal as well, has a small crease that runs all around the fountain as a drain, collecting the water that trickles from the lower basin and is also spouted by the grotesque faces.