(M151) We may surmise that in those Greek lands which have suffered severely from earthquakes, such as Achaia and the western coasts of Asia Minor, Poseidon was worshipped not less as an earthquake god than as a sea-god.(606) It is to be remembered that an earthquake is often accompanied by a tremendous wave which comes rolling in like a mountain from the sea, swamping the country far and wide; indeed on the coasts of Chili and Peru, which have often been devastated by both, the wave is said to be even more dreaded than the earthquake.(607) The Greeks often experienced this combination of catastrophes, this conspiracy, as it were, of earth and sea against the life and works of man.(608) It was thus that Helice, on the coast of Achaia, perished with all its inhabitants on a winter night, overwhelmed by the billows; and its destruction was set down to the wrath of Poseidon.(609) Nothing could be more natural than that to people familiar with the twofold calamity the dreadful god of the earthquake and of the sea should appear to be one and the same. The historian Diodorus Siculus observes that Peloponnese was deemed to have been in ancient days the abode of Poseidon, that the whole country was in a manner sacred to him, and that every city in it worshipped him above all the gods. The devotion to Poseidon he explains partly by the earthquakes and floods by which the land has been visited, partly by the remarkable chasms and subterranean rivers which are a conspicuous feature of its limestone mountains.(610) § 6. The Worship of Mephitic Vapours. (M152) But eruptions and earthquakes, though the most tremendous, are not the only phenomena of volcanic regions which have affected the religion of the inhabitants. Poisonous mephitic vapours and hot springs, which abound especially in volcanic regions,(611) have also had their devotees, and both are, or were formerly, to be found in those western districts of Asia Minor with which we are here concerned. To begin with vapours, we may take as an illustration of their deadly effect the Guevo Upas, or Valley of Poison, near Batur in Java. It is the crater of an extinct volcano, about half a mile in circumference, and from thirty to thirty-five feet deep. Neither man nor beast can descend to the bottom and live. The ground is covered with the carcases of tigers, deer, birds, and even the bones of men, all killed by the abundant emanations of carbonic acid gas which exhale from the soil. Animals let down into it die in a few minutes. The whole range of hills is volcanic. Two neighbouring craters constantly emit smoke.(612) In another crater of Java, near the volcano Talaga Bodas, the sulphureous exhalations have proved fatal to tigers, birds, and countless insects; and the soft parts of these creatures, such as fibres, muscles, hair, and skin, are well preserved, while the bones are corroded or destroyed.(613)