The two river-gods which also adorn this fountain are very old. Together with Marforio, now to be found in the Museum of the Capitol, they have the distinction of never having been buried since the downfall of Rome. Once they stood before "that most magnifi­cent of all Roman temples "-Aurelian's Temple of the Sun. Later they belonged to the Mediaeval Museum of Statues, a collection kept in or near the old papal palace of the Lateran, where they had been called Bacchus and Saturn. The Nile, who should have been unmistakable because of his emblem of the Sphinx, has now his proper designation; but the other statue has a curious history. It was originally the River Tigris, a river familiar to the Romans since the wars with Mithradates. When, under Paul III, Michelangelo placed these statues in their present position, some influential person suggested that the Tigris, no longer of any in­terest to the Romans, should be changed into the Tiber. The emblem of the Tigris-a tiger-was then altered to represent the Roman Wolf, and the Twins were added. Pirro Ligorio tells the story, and goes on to say that the fingers of one of the Twins were origi­nally a part of the Tiger's fur.

The erection of the bronze equestrian statue of Marcus Aurelius in the centre of the piazza was the first step in the design of the Campidoglio of to-day, for Michelangelo's admiration of the statue had been shared by Paul III, and the Pope brought it hither in 1538 when the embellishment of Rome, originally begun in honor of the visit in 1534 of Charles V, had become with both Pope and citizens a great and per­manent interest. This statue also had been a part of that Mediaeval Museum in the Lateran which was probably one of the places to visit when Charlemagne came to Rome to be crowned in old St. Peter's on Christmas Day, 800. The fagade of the Senate House, which forms the background to the piazza and its statues, is built in great part of travertine, so the struc­tural part of the fountain is of the same material. This consists of a huge niche, sixteen and a half feet in height, sunk into the foundation of the terrace before the main entrance to the Senate House. On either side of the niche is a pair of Doric pilasters, which support the floor of the terrace and its beautiful balustrade. A great stairway, down which the balustrade continues, connects this entrance of the Senate House with the piazza below; and the foundation of these steps, forming triangular wings to the niche, serves as a background to the river-gods. These figures lie one on either side of the semicircular basins containing the water.