[13] There is good reason to believe that such tombs were not _exclusively_ Etruscan, but were also used by the Latins and other nations at the same period, and this one may very well be early Roman. [14] The modern carriage-road, so called, was called Via Gabina in the time of Frontinus. The old Via Prænestina is now a bridle-road only for the first three miles out of Rome, to the Torre de’ Scavi; it is then a cart-road, called Via Collatina, with a branch road into it from the present carriage-road. [15] In the Map of Gell and Nibby, along the Via Prænestina will be seen the name _Pupinia_. The spot is just north of this, and not far off from the piece of road marked in the same map as the Via Collatina. [16] Frontinus, c. 22. [17] In the _Bullettino dell’ Instituto Archeologico_, and the _Civiltà Cattolica_, for the year 1861, it is stated that for the works of the iron railroad between the Via Labicana and the Via Gabina the _specus_ of the Aqua Appia was found, 450 yards (metres) from the Porta Maggiore. It was constructed of square stone of tufa, and was incrusted with _tartar_, had an acute vault, which was 5 ft. 9 in. high, and 2½ ft. wide. [18] This is on the line of the wall of Servius Tullius. It appears that Trajan made a reservoir here over the old one. The _specus_ of the Appia passes through the present gardener’s house lengthwise, from east to west. This _specus_ was found again in another excavation to the west of it, by the side of the present road. [19] “Substitit ad veteres arcus _madidamque_ Capenam.” (Juvenal, sat. iii. ver. 11.) “Capena grandi porta qua _pluit gutta_.” (Martial, lib. iii. epigr. 47.) The distance from the foot of the Cœlian to the Marrana is just a hundred yards along the line of the wall of Servius Tullius, across this part of the valley or great primitive foss. The ground on the side of the wall is all made earth and rubbish, and two aqueducts are carried on arcades against the wall, one on either side. These arcades have not been traced beyond the Marrana, the ground there being higher. At the Piscina Publica, where another pit was dug 20 ft. deep, the wall is built against the tufa rock, and there is a third _specus_ in a tunnel in the rock under the wall. [20] Or perhaps the road was a deep foss-way, and the _specus_ passed over the arch of the gate at this point, where four roads meet.