Stoned Oracle at Delphi
nucal writes: "Acording to the NY Times (free registration required, etc.) the Oracles at Delphi were under the influence of ethylene gas when they made their prophecies. Archeologists and geologists teamed up to discover the 'mephitic vapours' that 'inspired divine frenzies.'"
Ethylene is a part of a forward-feedback loop that causes fruit to ripen faster. That's why you put green tomatoes in a paper bag to ripen them - it concentrates the ethylene they outgas. It's also why "one bad apple spoils the bunch"
Apparently it "ripened" the ancients, too!