[Sidenote: Tabularium.] On the side of the Capitoline Hill towards the Forum, a very high and wide mass of building, now called the Palace of the Senator, and used for the transaction of urban business, stands. This is founded upon an ancient range of masonry of which a considerable part still remains, measuring about 220 feet in length, and 50 feet in height. An entrance has been made from the Via del Campidoglio, and as the wall was cut through for this purpose, the structure of the building may be best observed here. On the inner side red tufa has been used, and on the outer grey peperino, and the blocks are laid alternately lengthwise and crosswise, as in the Servian wall building. A great mass of masonry of this sort without cement, forms the main substructions of the building. Along the front run the traces of an arcaded passage, which anciently led across from one side to the other of the building. The arches were walled up by Nicolas V., in order to bear modern buildings above them. One has now been opened to show the architecture. A pavement of basaltic lava, such as was used in the streets of ancient Rome, has been found in the arcade, showing that it was a public passage. The architecture of the building is Doric, which points to an early date, and the capitals and cornice are of travertine. It is probable that another arcade ran above the one now traceable. A high flight of steps leads up into the chambers from the archway now walled up at the back of the Temple of Vespasian. From the architecture it may be concluded that these remains of a large ancient building date from the republican times of Rome, and are almost the only relics of that era. This ruin is generally called the Tabularium, but it has been shown by Mommsen that there is no ground for supposing that the name was ever applied to it in any ancient writings, and that the name is more properly Ærarium Populi Romani, or Ærarium Saturni, and that it was attached to the Temple of Saturn. Many of the temples in Rome had æraria attached to them, and it does not appear that any central place of deposit ever had the name of Tabularium alone, without further title, especially applied to it. The inscription which has been placed at the entrance, and records the construction of some building, or part of a building by Q. Lutatius Catulus, when consul, was placed where it now stands by Canina. It is supposed by Mommsen to refer to the repairs and alterations of the vaults under the Capitol, which were carried out in pursuance of Sulla’s plan of improvements on the Capitol, and after Sulla’s death were continued for many years by Q. Catulus.[66] CHAPTER III. THE COLISEUM AND ESQUILINE. [Sidenote: Meta Sudans.]