Quitting this, and descending into the valley again, if valley it may be called, we find a sort of grotto, in the hill side, with a recumbent statue, a spring of pure water, the source of the rivulet, and the appearance of former decorations that are now wanting, particularly of statues. This place is popularly called the fountain of the nymph Egeria, so celebrated for the artifice of Numa. It is, however, pretty certain that this is not the true spot; and, considering the proximity of the temple of Bacchus, the grotto is probably the remains of some Roman expedient to cool wine, and to drink it luxuriously. Religion may have been mixed up of old with these debauches, as we know politics and dinners go together in our own times. The recumbent statue is clearly no statue of a nymph. The work is thought by even the sceptics to be as old as the time of Vespasian. This grotto and the temple of Bacchus, probably, had some allegorical connexion, the one being a place to carouse in, the other a temple to sanctify the rites; and if we add the other fane to the whole, as an emblem of the manner in which drunkards render themselves _ridiculous_, we may be quite as near the truth as the antiquaries. We will quit these pleasant dales, and ride across the fields, a short mile, to the line of ruined tombs that marks the remains of the Appian Way. An extensive pile of ruins will naturally first attract our attention; and we will spur our horses up the sharp acclivity on which it stands, though by making a small _détour_, and getting into the rough road, that still leads out on the old route for a few miles, we might reach the summit more easily. On reaching this spot, we find the remains of a castle of the middle ages, with courts, walls, and towers, scattered about the fields, all built in the usual rude and inartificial manner of those structures, with a keep, however, that has the grace and finish of the Roman architecture. This keep is round, well preserved, much better, in short, than the rest of the edifice, which is crumbling around it. It is about eighty feet in diameter, and is constructed of vast hewn blocks of travertine; while the other parts of the work appear to be made of stones gathered in the fields, or taken from the foundations of the tombs. The latter was most probably the fact. The walls of this keep are thirty feet thick, the interior being little more than a small vaulted room. It formerly contained the sarcophagus that is still seen in the court of the Farnese Palace; for, in brief, this keep was merely one of the tombs of the Appian Way.