Note 19 — Chapter IV · PART I. THE AQUEDUCTS.

“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.