[1] During the first season that I was resident in Rome, it was my habit to go with my friend Mr. William Long, of Balliol College, Oxford, then resident in Rome, into the Catacombs every Monday morning, and along the line of the Aqueducts also once or twice a-week, when the weather permitted. We procured all the best maps of the Campagna that were to be had, but could find none that would enable us to trace the course of the Aqueducts. Moltke’s map is the best as far as it goes; but, being intended as a military map only, he paid no attention to the antiquities. The one known in England by the name of Gell, and in Rome by the name of Nibby, is made especially for the Antiquities; but it is on a small scale, and we found it impossible to trace the Aqueducts upon it. Eventually I have had one made on a large scale, to make it clear, have added the other Antiquities, and then had it reduced by photography to two smaller sizes: one very small, to give the general lines only; the other on a size convenient for the pocket; and, by using the portion near Rome separately, it makes a good and convenient map for the purpose. [2] Frontinus is usually said to have died A.D. 106. [3] See notably Plutarch, Vita Anci Marcii; Dionys., Hal. Ant. Rom., lib. iii. c. 679, sect. 9; Strabo, lib. v.; Cassiodorus, lib. vii. cap. 6, &c. [4] These wells may have included the cisterns for holding rain-water, one of which exists on the Palatine. [5] In the best text, that of the MS. at Monte Cassino, and in the best printed edition of the text, that of Buecheler (Lipsiæ, 1858), the passage runs “Salubritatem enim ægris corporibus afferre creduntur, sicut _Camænarum, et Apollinis, et Juturnæ_.” The spring of the Camænæ or Muses referred to, is that which existed in the grove outside the Porta Capena, and beneath the western slope of the Cœlian. There was an Area Apollinis in the same Regio, and possibly there was a spring there; but no writer refers to it. A stream, now subterranean, still exists, and is very copious, running into and through the Cloaca Maxima; it may be seen in the excavations of the Forum Romanum. This subterranean stream comes from three different springs; the source of one is near the Arch of Titus, or more immediately in front of the usual entrance to the Palatine;—a second has its source near the foot of that part of the Quirinal Hill on which the Torre de’ Conti and the Torre delle Milizie are situated; it now emerges in a cellar under a shop behind the church of S. Hadriana;—a third comes from the prison of S. Peter, at the foot of the Capitol. These streams meet near the church of S. Maria Liberatrice and the celebrated three columns of the temple of Castor and Pollux; by their union they formed the lake usually called after Curtius, but by Ovid the Lacus Juturnæ (Ovid. Fasti, l. i. ver. 708). This is not the same as the stream so called on Nolli’s Map. The lake was between that part of the Velabrum of the Palatine on which the church of S.