extends from Mount Soracte (S. Oreste) southwards to the Alban Hills, and from the Apennines westwards to the sea. It is watered by the Tiber and numerous smaller streams; but there are no marshes except the salt ones by the sea. The soil is mostly composed of tufa rock, covered with a few feet of soil--decayed vegetable matter. This causes the malaria: for the first rains, after the heat of summer, which has burned up all the vegetation, pass through the soil and rest upon the rock; then the hot sun after the rains draws up the noxious gas, which being dispersed through the air, if inhaled during sleep, or upon an empty stomach, produces fever. If the soil, which for many ages has been allowed to lie fallow, were properly irrigated and cultivated, all this could be obviated. In the last few years more has been brought under the plough; and if the government would only plant trees by the road-sides and in the waste places, the Campagna would soon become as healthy as in the days of Pliny, who thus describes it:--"Such is the happy and beautiful amenity of the Campagna that it seems to be the work of a rejoicing nature. For, truly, so it appears in the vital and perennial salubrity of its atmosphere; its fertile plains, sunny hills, healthy woods, thick groves, rich varieties of trees, breezy mountains, fertility in fruits, vines, and olives; its noble flocks of sheep and abundant herds of cattle; its numerous lakes, and wealth of rivers and streams pouring in upon its many seaports, in whose lap the commerce of the world lies, and which run largely into the sea, as it were to help mortals." The surface is by no means flat, but undulating, like the rolling prairies of America, and presents many points of interest and study to the artist and the rambler. * * * * * PORTA FLAMINIA. (_Porta del Popolo._) _Passing through the Porta del Popolo_, built in 1561 by Vignola, a short walk under the walls, to the right, brings us to the Muro Torto, a piece of masonry of the time of Sylla, and held to be under the special protection of S. Peter (Procopius, "B. G." i. 13). VILLA BORGHESE. _Closed on Mondays, Wednesdays, and Fridays._