The Porta Capena is represented twice in the reliefs of Trajan built on to the Arch of Constantine. In the days of Tullus Hostilius, B.C. 668, Horatius killed his sister outside this gate. "A tomb of squared stone was raised for Horatia, on the spot where she fell" (Livy, i. 26). We now arrive at the river Almo (Marrana), which flows through THE VALLEY OF THE MUSES, under the Cœlian Hill, in which is the Fountain of Egeria, whence flowed the perennial fountain by whose waters Numa caught inspiration from the lips of his lovable nymph. Juvenal describes the spot in his description of the parting of Umbricius and himself: "This is the place where Numa consulted his nocturnal friend the nymph: now the grove of the sacred font is occupied by the remains of Jews." "In the valley of Egeria we descended into caves unlike the true." They strolled from the Porta Capena whilst the waggon was loading. At length Umbricius says: "The sun is getting low--I must depart; for long ago the muleteer gave me a hint by cracking his whip." "Numa was commanded by the nymph Egeria to consecrate that place and the fields about it to the Muses, where he had often entertained a free intercourse and communication with them; and that the fountain which watered that place should be made sacred and hallowed for the use of the vestal virgins, who were to wash and clean the penetralia of their sanctuary with those holy waters" (Plutarch). Livy (i. 21) thus describes it: "There was a grove, in the midst of which, from a dark cavern, gushed a fountain of flowing water, whither often, because without witness, Numa went to have an interview with the goddess, and which grove he consecrated to the muses, that their councils might be held there with Egeria." The fountain may still be seen under the Cœlian, over the wall on the left;--there is a bath-house of the middle ages built over it. It is in the grounds of the villa of Baron Hoffmann, _to whom application must be made to visit it_. _Crossing the_ Marrana, _we take the first turning on the right_, VIA ANTONINA. _This lane leads to the_ BATHS OF CARACALLA. _Admission one lira; Sundays free._ A favourite spot of Shelley's--"among the flowery glades and thickets of odoriferous blossoming trees, which are extended in ever winding labyrinths upon its immense platforms and dizzy arches suspended in the air." So the poet wrote of this spot. But now it is all changed: the hand of the explorer has ruthlessly pulled up the trees, and scraped the wild flowers and weeds from the ruined walls, exposing beautiful mosaic pavements, it is true, but which hardly repay for the loss of nature's verdure. The magnificent Thermæ of Caracalla display in the clearest and most complete manner the skeleton of an edifice of this kind--these glorious ruins standing, as it were, intact before us.