__NOTOC__ Lago di Agnano or Lake Agnano was a circular lake, some 6½ km in circumference, which occupied the crater of the extinct volcano of Agnano 8 km west of Naples, Italy. It was apparently not formed until the Middle Ages, as it is not mentioned by ancient writers; it was drained in 1870. On the south bank are the

Stufe di San Germano In Schenkerian theory, a scale-step (german: Stufe) is a triad (based on one of the diatonic scale degrees) that is perceived as an organizing force for a passage of music (in accordance with the principle of composing-out). In ''Harmony'', Sc ...

, natural

sulphur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...

eous vapor baths, and close by is the

Grotta del Cane The Cave of Dogs (Italian: ''Grotta del Cane'') is a cave near Naples, Italy. Volcanic gases seeping into the cave give the air inside a high concentration of carbon dioxide. Dogs held inside would faint; at one time this was a tourist attracti ...

. From the floor of this cave warm

carbonic acid gas Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...

constantly rises to a height of : the fumes render a dog insensible in a few seconds. Remains of an extensive Roman building and some statues have been discovered close by.

References

;Attribution Former lakes of Italy Volcanic crater lakes Lakes of Campania {{Campania-geo-stub