First, it should be remarked, that the water of the Appia was augmented by an additional stream. This was not accomplished till the time of Augustus. The source of this latter[23] was on the same side of the Via Prænestina, but a little nearer to Rome (near the sixth milestone) we are told, and its course was, like the main stream, entirely underground. It was more direct, as its length was less than six miles and a-half, while the original stream, by its windings, required about eleven miles to complete the same distance[24].
It joined, however, the Appia at the “Spes (Specus) Vetus,” and at the Gemelli[25], which was under (infra) the “Old Specus,” it could be measured. This is an important landmark; it is well at once to observe that the usual interpretation of the passage as referring to a “Temple of Spes,” and the statement that a temple occupied the site of some ruins which are marked thus in a few maps, (in most, Templum Veneris et Cupidinis) does not seem to fit the circumstances. It is proposed to read in both these two instances “Specus Vetus.” The expression occurs, altogether, five times in Frontinus, and it will be most satisfactory therefore to consider the passages together, which will be done more conveniently in connection with the next aqueduct described.
The Torquatian and Plautian, or Pallantian gardens, seem by the context to have occupied a spot on either side of the point of junction of the two streams. The Torquatian gardens are not mentioned elsewhere, and with respect to the Plautian[26] (which is only conjectural, and has the authority of neither of the early MSS.), it has been suggested to read Pallantian, which gardens are mentioned twice elsewhere by Frontinus in connection with the Specus Vetus, besides once in such a way as to imply the same[27].
The Torquatian gardens probably occupied the space between the outer wall and the modern “Via di Porta Maggiore,” and were probably those of Titus Manlius Torquatus, a member of an important patrician family; Livy mentions at least three generations of that name. This ground shews numerous remains of aqueducts and reservoirs, and here also is the fine building of the third century called the Minerva Medica, which was probably the nymphæum of some thermæ of that period[28]. The Pallantian gardens is a natural name for those belonging to the Sessorium, or the Sessorian fortified Camp and Palace[29], and occupied the low ground near it. They would therefore be to the south of, but adjoining to, the Torquatian gardens.
II. The Anio Vetus (B.C. 272).
“Forty years after the Appian aqueduct had been completed, and in the year A.U.C. 481 (B.C. 272), Marcus Curius Dentatus, who bore the office of censor with Lucius Papirius Cursor, contracted to bring into the city the water of the Anio, which is now called the Anio Vetus, from the spoils taken of Pyrrhus[30].
“The Anio Vetus takes its rise beyond Tibur (now called Tivoli), outside the gate, at the twentieth milestone, where it parts with some of its water for the use of Tibur. Its course has in length, in consequence of the difficulties caused by the levels, 43 miles. Of this for 42 miles and 779 paces, the stream is underground, and for 221 paces (about 350 yards) on a substructure above ground.
“Near the fourth milestone within the new road (infra novum) the Anio Vetus crosses between the arches from the Via Latina into the Via Lavicana, and has (there?) a reservoir (or piscina). Thence just within the second milestone it gives a part of its water into the specus, which is called the Octavian, and this comes in the direction of the New Road to the Asinian Gardens, whence it is distributed through that neighbourhood; but its direct channel, following the specus (or conduit) coming within the Porta Esquilina, along the Spes (Specus?) Vetus, is drawn off for distribution in the city, through the high channels[31].