Descriptions, dating back 2000 years, of a sweet smelling gas permeating the temple and providing the inspiration for seeing into the future were regarded as scientific heresy until Hale's team explored the site on Mount Parnassus, 100 miles north west of Athens. The facts now unusually marry with the myths surrounding the priestesses who pronounced on some of the ancient worldıs most momentous events from their subterranean temple-chamber.

The scientists found two geological fault lines crossing directly beneath the temple allowing both water and gas to seep into the enclosed "prophecy" chamber. The final clue to solving this ancient riddle was the discovery of a mind-bending petrol-based gas, ethylene.

The priestesses were portrayed (see above) looking into a bowl of water containing the gas before warning the likes of Oedipus of their portentous futures. Despite the predictions, the tragic Oedipus could not change his fate - that he was to murder his father and marry his mother.

The oracle's pronouncements were often mysterious and difficult to decipher. The ancient king Croesus consulted the oracle about a military campaign. The priestesses foresaw the destruction of a kingdom. Unfortunately Croesus never saw that they meant his own!

Mark Winter

The key to this mystery might be in the famous "Know thyself" inscription, which adorned the ancient temple's wall.

The inner quest for self-knowledge can put you in touch with what mystics call "oracular time" where the past, present future merge into one.

Famous psychologist Carl Jung referred to this as synchronicity, which he saw as the force behind such "personal oracles" as the Chinese I-Ching and Tarot Cards.

Nostradamus and the American psychic Edgar Cayce are examples of more recent oracles, whose prophecies are been intensely scrutinised and interpreted.