CLOACA MAXIMA. This was a subterranean passage of vast extent, by which the whole, or a great part, of the filth of ancient Rome was conveyed to the Tiber. Drains from the lower parts of the city around the forum,,,and from thekther valleys, were commenced by Tarquiuius Priscus; but the construction of the C. M. is attributed by Livy to Tarquinius Superbns. Niebuhr is of opinion that it was at first intended to drain the valley of the forum; but it appears to have been subsequently extended, and connected with the smaller cloaca:. Running from the forum past the temple of Vesta, it terminated at the Tiber, where the mouth of it is still visible. It consisted of 3 large arches, one within the other. The space inclosed by the innermost vault was upwards of 13 ft. in width, and of a corresponding height. The arches were built of large blocks of stone, fixed together without cement, of the uniform size of rather more than 5 ft. 5 in. long, and 3 ft. high. The species of stone used bears evidence to the antiquity of the construction, being the material which was employed in the most ancient public edifices. The sewer was kept in a state of efficiency by a continual stream of super
fluous water from, the aqueducts. Large portions of this and of the other cloaca remain, in some places still visible, but generally buried, by the accumulation of soil, at a con siderable depth below the present level of the streets. During the republic, the surveil lance of the Roman cloacm was one of the duties performed by the censors. The C. M. was subjected to repair by Cato and his colleague in the censorship. Agrippa, when tedile, obtained praise for his exertions in cleansing and repairing the cream, and is recorded to have passed through them in a boat. Under the empire, officers called euratores cloacaram urbis were appointed for their supervision. So thoroughly was the city undermined by these large sewers, that Pliny calls it albs pensilis. a city suspended in the air rather than resting upon the earth. Drains of the same description, but of smaller dimensions, existed in some others of the ancient Roman cities.