Day in the Life of the Oracle of Delphi

Civilization

Greece

Occupation

The Pythia — oracle-priestess of Apollo

Material

Laurel & vapor

Period

c. 500 BC

Kings crossed seas for one question. The Pythia prophesied from a bronze tripod over a cleft in the bedrock — one day a month, nine months a year. Croesus of Lydia asked if he should attack Persia and was told a great empire would fall. It was his own.

The job

On the seventh day of the month, nine months a year, one woman took her seat at the heart of the Temple of Apollo at Delphi. She was the Pythia, the priestess through whom the god was said to speak. She sat on a three-legged tripod in the adyton, the sunken inner chamber, above a cleft from which, the ancient sources say, rose a vapour the Greeks called pneuma. She breathed it, passed into trance, and answered.

No oracle in the Greek world was consulted more. Kings, generals and whole cities sent envoys to Delphi and shaped wars, colonies and laws around the replies. The office endured, in one form or another, for close to a thousand years.

The Croesus test

The most famous consultation was a trap that closed on the man who set it. Croesus, king of Lydia, first tested the great oracles and judged Delphi the one that could be trusted. Then he asked the real question: whether he should march against the rising power of Persia.

The Pythia answered that if he attacked, he would destroy a great empire. Croesus crossed the river Halys, gave battle, and lost. The great empire that fell was his own. Herodotus, who preserves the story, treats the reply not as a fraud but as a riddle the king was too eager to read in his own favour.

The gas beneath

For a long time the vapour was the least credible part of the account. When French archaeologists excavated the temple in the 1890s they found no chasm and no gas, and many scholars concluded the ancient writers had imagined it. In 2001 a geologist, an archaeologist and a chemist reopened the case. De Boer, Hale and Chanton reported two intersecting faults beneath the sanctuary and light hydrocarbon gases — methane, ethane and ethylene — in the spring water and the travertine crust around it. Ethylene was the arresting detail: sweet-smelling, once used as a surgical anaesthetic, and capable of producing euphoria and trance in small doses. A 2002 paper defended the reconstruction across geology, chemistry and the texts.

The identification is not settled. A 2006 survey of the site found mainly methane, ethane and carbon dioxide, and proposed that the sweet scent the ancients described came from benzene rather than ethylene. In 2007 a philosopher and a classicist argued that the measured concentrations were far too low to intoxicate anyone, and that the textual case had been overstated. The geological setting is now broadly accepted. The exact gas, and whether gas alone can explain what the Pythia did, remains open.

Where to see it

The chamber is gone, but Delphi survives. The Temple of Apollo still stands above the sacred way, and a copy of the omphalos — the stone that marked the centre of the world — sits where the god's was kept. The originals are a short walk downhill in the Delphi Archaeological Museum: the carved omphalos, the archaic Sphinx of the Naxians, and the acanthus column of the Dancers that once carried a bronze tripod.

Sources

1. de Boer, Hale & Chanton — New evidence for the geological origins of the ancient Delphic oracle (Greece) (2001), Geology 29(8): 707–710
2. Spiller, Hale & de Boer — The Delphic Oracle: A Multidisciplinary Defense of the Gaseous Vent Theory (2002), Journal of Toxicology: Clinical Toxicology 40(2): 189–196
3. Etiope et al. — The geological links of the ancient Delphic Oracle (Greece): a reappraisal of natural gas occurrence and origin (2006), Geology 34(10): 821–824
4. Foster & Lehoux — The Delphic Oracle and the ethylene-intoxication hypothesis (2007), Clinical Toxicology 45(1): 85–89
5. Herodotus — Histories 1.53, the Croesus oracle (Godley ed.), Perseus Digital Library
6. Hellenic Ministry of Culture — Archaeological Site of Delphi (official)