From the Porta Maggiore one branch of the Aqua Felice is carried across the great foss to the Lateran, through the piers of the arches of Nero, and down a cascade-pipe into the old specus of the Appia, and along that to the fountains and reservoirs at the Lateran. This is the branch that goes straight on from the corner of the Sessorium to the west. Another more important branch of the Aqua Felice turns short to the north from the same angle and over the Porta Maggiore, along the city wall to the Porta S. Lorenzo, in a new channel very badly and clumsily built of rough stone from the materials of the old aqueducts, making use of the piers of the Claudian arcade as far as they go, and then of the inside of the wall of Aurelian over the Marcian arcade. The Aqua Felice having here been brought to a higher level, that is to say, the descent from the piscinæ being less rapid than that of the Marcia, after passing the Porta Maggiore, goes over the Marcia upon the Arch of Augustus at the Porta S. Lorenzo. There is a castellum aquæ for it in the wall just to the south of the Porta S. Lorenzo, where the water may be heard rushing through, and the surplus water runs off into an ancient drain on the outside of the wall. With the rapidity of all the public works under that energetic Pope, the undertaking, a decree for which he had signed in April, 1585, was completed in two years, by the labours of from 2,000 to 3,000 men, and the waters were seen to gush from their sculptured fountain in the Piazza di Termini, on the 15th of June, 1587. The Aqua Felice was conducted for fifteen miles underground, and for seven miles upon arcades. Besides the Aqua Felice, the Via Felice and the Via Sistina (Sixtus) in continuation of it, and many other great works were inaugurated by the same Pope, who has been called the real founder of modern Rome. Other old subterranean conduits are employed to carry the pipes of the Felice where convenient for the purpose of conveying water to different parts of the town.
Junctions of the arcade of Sixtus V., or Aqua Felice, with that of the Claudia, take place at an angle where the Torre Fiscale has been built, and again at another angle where there is an archway called the Porta Furba, about two miles from Rome, and a most picturesque ruin of a piscina, with a tall tower by the side of it, in which is the ventilating-shaft of the conduit. The difference of construction and of level is very evident, and the three conduits carried on the same arches may be seen distinctly. The construction of the Claudia (VIII.) is of large square blocks of stone. The Anio Novus (IX.) is merely an additional brick conduit, the work is part of that of Claudius and Nero, and is carried over the original one at a great height from the ground. Near the city only small portions of this upper conduit remain here and there, as, for instance, over the Porta Maggiore, and in a few places on the wall. In some places, the arcade of the Aqua Felice runs parallel to the Claudian for a considerable distance, and is joined to it at both ends, as near the Porta Furba. This lower arcade carried part of the conduits of the Aqua Marcia, Tepula, and Julia, which ran from the Porta Furba into the city parallel to the later one of Claudius, at a lower level.
Where the Aqua Felice enters the city, it is carried on the piers of the arcade of Claudius, from the junction with the arches of Nero, over the Porta Maggiore to the old castellum at the corner of the wall, where it turns at a sharp angle. Here the arches of Claudius cease; but the conduit of the Aqua Felice is continued along the city wall, of which it forms part, upon the ancient embankment as far as the Porta S. Lorenzo, and over the archway of Augustus there, using one of the older conduits. It then makes a sharp turn to the west, and after being carried along the north side of the road for a short distance, crosses it again on an archway built for the purpose by Sixtus V., as recorded by an inscription upon it; then it turns sharply to the west again, and is carried on an arcade between the road on the north and the railway on the south, to the great inner agger, which it reaches at a point near the Thermæ of Diocletian and the railway station. It is then carried in an old specus in that bank along the east side of the Thermæ, and turns at an angle to the north, at the Via Nomentana, near the Porta Nomentana, a little to the south of the modern Via di Porta Pia; then along the north side of the Thermæ till it arrives at the great reservoir behind the fountain of Termini. The specus is three feet wide, and the water in it is usually from three to four feet deep, running with a rapid current about five miles an hour, and constantly flowing day and night. Thence it is carried in pipes to the different reservoirs and fountains of the upper town. It also supplies the lower part of the city from the Ghetto to the Marmorata, along the bank of the Tiber.
SUMMARY.
Frontinus, who wrote in the time of Nerva and Trajan, mentions (as we have seen) nine aqueducts[202], reckoning as distinct several branches, or additional channels, subordinate to others more important. There is one more important record to which reference has not hitherto been made, namely, the summary at the end of the Curiosum and Notitia, in which nineteen are enumerated.
The entry in the Summary of the Regionary Catalogue is as follows:—
| Aquæ XIX. | |
| I. | Traiana [X.] |
| II. | Annia (or Anio Vetus?) [II.] |
| III. | Attica (Anio Novus) [IX.] |
| IV. | Marcia [III.] |
| V. | Claudia [VIII.] |
| VI. | Herculea [XVII. Almo?] |
| VII. | Cerulea [IX.] |
| VIII. | Julia [V.] |
| IX. | Augustea [I.] |
| X. | Appia [I.] |
| XI. | Alseatina [VII.] |
| XII. | Ciminia (?). |
| XIII. | Aurelia [XII.] |
| XIV. | Damnata (Cloaca Maxima?). |
| XV. | Virgo [VI.] |
| XVI. | Tepula [IV.] |
| XVII. | Severiana [XIII.] |
| XVIII. | Antoniana [XIV.] |
| XIX. | Alexandrina [XV.] |
Those not previously mentioned are (1.) Attica, (2.) Herculea, (3.) Cerulea, (4.) Augustea, (5.) Ciminia, (6.) Damnata.
1. Attica is supposed by Fabretti to be the same as Alseatina [VII.], but then how is the number of nineteen to be made up? It was probably the Anio Novus, as already described. [See IX.]