“Afterwards Caius Cæsar, (Caligula,) who succeeded Tiberius, considered seven aqueducts scarcely sufficient for public purposes and private amusements, and began two new aqueducts in the second year of his rule as Emperor, when Aquilius Julianus and P. Nonius Asprenas were consuls (i.e. A.D. 38), in the year of Rome 789, which work Claudius in a most splendid manner finished and dedicated, on the calends of August, in the year of the city 803 (i.e. A.D. 52), when Sulla and Titianus were consuls[116]. “To one, which was brought from the springs of Cæruleus and Curtius, the name of _Claudia_ was given. This one is next in order of excellence to the Marcian. “The other, because two streams of the Anio had begun to flow into the city, so that they should be more easily distinguished by their names, began to be called _Anio Novus_. It ruins all the others[117]. To the former Anio the cognomen of _Vetus_ was added[118]. “The Anio Novus and Claudia are carried from the _piscinæ_ upon higher[119] arches, so that the Anio is the highest of the two. Their arches come to an end after the Pallantian Gardens, and thence they are carried down in pipes for the use of the city. “But first of all the Claudia transfers a part of its water on to the arches which are called the Neronian, at the _Spes (Specus) Vetus_. These, being continued in a direct line along the Mons Cœlius, are terminated close to the temple of Claudius. They disperse the quantity which they had received either about the ‘Mons Cœlius’ itself, or in the Palatine, in the Aventine and the Transtiberine Region[120].” VIII. THE CLAUDIA. “The Claudia begins on the Via Sublacensis[121], at the thirty-eighth milestone, about 300 yards off the road towards the left. There are two very large and beautiful springs, one called Cæruleus, from its blue appearance, the other Curtius[122]. It receives also the spring which is called Albudinus, of such excellence, that when there is need of adding it to the Marcia, the latter loses none of its quality by the addition. The spring of the Aqua Augusta, because the Marcian seemed to be sufficient for itself, was turned aside into the Claudian; nevertheless it was retained as a protection for the Marcian, but so that the Augustan might be added to the Claudian, if the channel of the Marcian was not capable of receiving it[123]. “The channel of the Claudia is 46 miles, 406 paces in length; of this, 36 miles, 230 paces is by a subterranean course: on work above ground 10 miles, 176 paces, and out of this on arched work, in many places in the upper part, 3 miles, 76 paces; and near the city from the seventh milestone, by a substructure of channels for 609 paces, on arched work 6 miles, 491 paces[124]. “The Claudian was the second in height as to level[125].”