Another branch from the great reservoir went straight across to the Palatine, and from thence to the Capitol; it first follows the line of the road down the Clivus Scauri, on the left or southern side, and a fragment of it is visible opposite to the church of SS. John and Paul, as seen in No. 305. At the foot of the Clivus Scauri it formed an angle, and passed against the cliff on which the apse of the church was afterwards built; it now forms the lowest and last of the series of arches that are carried across the road to support the side of the church. Then, after this angle to the north, it resumes its course to the west upon the arches across the valley to the Palatine, which was a double arcade; but the lowest tier of it only remains, as is shewn in 116. A portion of the upper tier is also visible at the end of it; an arch of this upper tier remains, which, having been made into a back gate of the Palatine, has been suffered to remain, and is shewn in No. 72. A large reservoir for it was made at the south-west corner of the Palatine, on which the palace of Commodus was afterwards built; part of this reservoir and _specus_ is shewn in 683 (made from a drawing). The _specus_ went across the middle of the Palatine, and has been found more than once in some of the recent excavations, but not understood. It was then carried on the bridge of Caligula to the Capitol, a small portion of which remains connected with his palace, as is shewn in Nos. 1447 and 1451. The third branch from the great reservoir over the arch of Dolabella on the Cœlian was made in the time of Trajan, to carry water to supply the thermæ on the Aventine, called after Sura, the cousin of the Emperor; these thermæ were closely connected with the private house of his family, rebuilt in his time, and called in the Regionary Catalogue “Privata Trajani,” of which there are considerable remains, now subterranean. The first place where this branch of the aqueduct is visible is in another reservoir (1147) against the cliff of the Cœlian, opposite to S. Balbina. This is partly above the level of the hill, and has been thought part of the Palace of Commodus, on the Cœlian (which may possibly have been built over it, but the existing remains are of the time of Trajan). The lower part is under this, and is excavated in the cliff. These were brought to light in the excavations of A.D. 1868 (559, 1008, 1009, 1010, 1011). The plan and section of it are to be seen in 1150*, 692*. Against the cliff the aqueduct formed one of the usual angles towards the north, and this was carried across the valley on the _agger_ or bank of Servius Tullius, first passing over the arch of the gate of the Porta Capena, above the Aqua Appia, on a much higher level, and on an arcade, probably a double arcade, like the Arches of Nero near the Porta Maggiore, on account of the great height at which the water had to be carried from one hill to the other. All that remains of this lofty arcade is a line of brick piers