Note 591 — BOOK II. AN ACCOUNT OF THE WORLD AND THE ELEMENTS. (continued 2)

This circumstance is mentioned by Seneca, Nat. Quæst. vi. 28, as occurring “pluribus Italiæ locis;” it may be ascribed to the exhalations from volcanos being raised up into the atmosphere. It does not appear that there is, at present, any cavern in Mount Soracte which emits mephitic vapours. But the circumstance of Soracte being regarded sacred to Apollo, as we learn from our author, vii. 2, and from Virgil, Æn. xi. 785, may lead us to conjecture that something of the kind may formerly have existed there.