The Campagna is an uninhabited plain, surrounding the city of Rome, bounded on one side by the sea, and on the other by an amphitheatre of hills, crowned with towns, villages, and villas, which form the finest landscapes that can be imagined. The ancient Romans were wont to seek shelter from the scorching heats of summer, among the woods and lakes of those hills; and the Cardinals and Roman Princes, at the same season, retire to their villas; while many of the wealthier sort of citizens take lodgings in the villages, during the season of gathering the vines. On the road from Rome to Tivoli, about three miles from the latter, strangers are desired to visit a kind of lake called Solfatara formerly Lakus Albulus, and there shown certain substances, to which they give the name of Floating Islands. They are nothing else than bunches of bullrushes, springing from a thin soil, formed by dust and sand blown from the adjacent ground, and glued together by the bitumen which swims on the surface of this lake, and the sulphur with which its waters are impregnated. Some of these islands are twelve or fifteen yards in length; the soil is sufficiently strong to bear five or six people, who, by the means of a pole, may move to different parts of the lake, as if they were in a boat. This lake empties itself, by a whitish, muddy stream, into the Teverone, the ancient Anio; a vapour, of a sulphureous smell, arising from it as it flows. The ground near this rivulet, as also around the borders of the lake, resounds, as if it were hollow, when a horse gallops over it. The water of this lake has the singular quality of covering every substance which it touches with a hard, white, stoney matter. On throwing a bundle of small sticks or shrubs into it, they will, in a few days, be covered with a white crust; but, what seems still more extraordinary, this encrustating quality is not so strong in the lake itself, as in the canal, or little rivulet that runs from it; and the farther the water has flowed from the lake, till it is quite lost in the Anio, the stronger this quality is. Those small, round encrustations, which cover the sand and pebbles, resembling sugar-plums, are called Confetti di Tivoli. Fishes are found in the Anio, both above and below Tivoli, till it receives the Albula; after which, during the rest of its course to the Tiber, there are none. The waters of this lake had a high medical reputation anciently, but they are in no esteem at present.