Biology 202
2004 Second Web Paper
On Serendip

The city of Delphi, in which the ancient ruins of the Temple to Apollo still remain, lies on the southern slopes of Mount Parnassus, 100 miles northwest of Athens. The ancient Greeks considered Delphi the center of the universe. Legend has it that when Zeus unleashed two eagles from opposite ends of the earth in order to locate its center, the two eagles met over Delphi. (1) Delphi was also famous for its oracle; a priestess who could communicate with the gods and predict one's future in exchange for gifts. Both rulers and everyday people journeyed to Delphi to consult the oracle for her advice. (2)

The oracle worked in the following way: a priestess would sit in a small underground room and breath vapors from the ground while drinking water or inhaling mist from the warm spring beneath the Temple of Apollo. She would enter an exalted state of mind and give advice as if in a trance. (3) While in this state, she would mutter words, in a somewhat cryptic manner, and a priest would translate them to the person seeking advice. Sometimes her words were just ramblings. Other times her answers went over her questioner's head. On at least one occasion, the priestess is said to have gone into seizures and died. (3)

The existence of this oracle is not disputed, but how and why it worked has been questioned. How was it possible for this young woman to enter a trance-like state and give people supposedly relevant advice and true predictions of their futures? A recent hypothesis claims that ethylene gas, a common hydrocarbon found in nature, was detected in rocks and water near the Temple of Apollo and could have been responsible for producing the trance-like state. In high doses, ethylene gas can even cause death, which would account for the fate of at least one of the priestesses.

Ethylene (molecular formula H2C=CH2) is a sweet smelling gas known to effect the nervous system. Ethylene gas is naturally emitted by fruits, flowers, and other vegetation. It is the substance that causes fruits to ripen. Among the many changes that ethylene causes is the destruction of chlorophyll. With the breakdown of chlorophyll, the red and/or yellow pigments in the cells of the fruit are uncovered giving the fruit its ripened appearance. (4) Small amounts of ethylene are also found in volcanic emissions and natural gas. The production of ethylene from inside the earth led researchers to analyze the rocks and springs located beneath and surrounding the Temple of Apollo in search of answers of the workings of the oracle.

Geologist Jelle Z. de Boer of Wesleyan University in Connecticut and Archaeologist John Hale of the University of Louisville led the research team at Delphi. The team conducted tests on the Delphi rock and on the water of a nearby spring. Both contained the presence of methane, ethane, and ethylene. (5) They also examined pieces of travertine, a limestone stalactite deposited by an ancient spring, and detected measurable amounts of ethane and methane there as well. (3) The team concluded that the Temple of Apollo sits on crisscrossing geological faults. When the faults shift and rub each other, a large amount of heat is given off, which causes hydrocarbons to vaporize and come up though fissures in the ground. In this way, the gases can seep into nearby springs or fuse into crystalline rock formations.

The results from the tests indicate the presence of ethylene in the rocks and springs at Delphi. The geological aspect also provides a logical explanation of how the gases could have come up to the surface. This opens the possibility that ethylene gas was present in the chamber where the priestess sat since it was detected in the same vicinity. If this was the case, did the ethylene gas have an effect on the priestess and was it responsible for her trance-like state and ultimately influence what she said?

The main threat of ethylene gas is that it can displace oxygen in the air, which can result in symptoms associated with oxygen deficiency. A lack of oxygen to the brain can cause symptoms such as rapid breathing, diminished mental alertness, impaired muscular coordination, faulty judgment, depression of all sensations, emotional instability, and fatigue. As asphyxiation progresses loss of consciousness may result, eventually leading to convulsions, coma, and even death. (6) High concentrations of ethylene, as well as ethane, propane, and propylene, may have anesthetic-like effects (central nervous system depression) causing drowsiness, dizziness, and confusion. (6)

Historically, ethylene was in fact used as an anesthetic until less flammable compounds were discovered. The process by which general anesthetics work is still unknown. The two main hypotheses are the "lipid theory" which proposes that anesthesia directly interacts with cell membranes involved in brain functions (7) and the "protein theory" which suggests that anesthesia blocks sodium channels in the nerve membrane, which inhibits nerve impulses. (8) Biophysicists Wu and Hu have proposed another theory in which anesthesia works by reducing oxygen to the brain. "In essence, their mechanism holds that anesthetics act as barriers to oxygen transport in both membranes and proteins, reducing oxygen availability to the brain." (7) This idea seems to draw from both of the above hypothesis-that some function of/in membranes and proteins is altered (through lack of oxygen in this case). The concept of decreasing oxygen to the brain can also be applied to ethylene gas, for it displaces oxygen as well, which could account for why it worked as an anesthetic.

Attempting to explain how the oracle at Delphi worked through geological findings is one way to try to understand this mystical being. It seems likely that ethylene gas was present in the chamber where the priestess sat since it was detected in mineral formations and springs under and surrounding the Temple of Apollo. Was the ethylene gas indeed capable of producing the trance like state? The strongest support for this argument is that ethylene gas affects the nervous system by displacing oxygen to the brain. The symptoms of oxygen deficiency described above do include loss of consciousness. As one source writes, small doses of ethylene "produce a floating sensation and euphoria. In other words, just what an oracle needs to start having visions." (2) Its former use as an anesthetic also supports this idea, especially if Drs. Wu and Hu's hypothesis that anesthetics work by decreasing oxygen to the brain turns out to be correct, since that would imply that ethylene's displacement of oxygen could lead to anesthetic/trance-like effects. On that note, until further research is conducted on anesthetics, the ethylene gas hypothesis remains only a possible explanation for what went on thousands of years ago at the oracle at Delphi.

References

1) Greece Taxi Tours information website , good background information on ancient Delphi as well as travel information to modern Delphi.
2) Wikipedia, a free online encyclopedia , provides good links to related concepts.
3) What You Need to Know About website , contains many geology related articles.
4) Ethylene gas, provides interesting information on ethylene gas, particularly its relevance to the fruit industry.
5) Hallucinogens website , an article from the Washington Post with the history and geological findings at Delphi.
6) The BOC Group website , a material safety and chemical data sheet on ethylene gas.
7) Article from a UPI Science correspondent , describes the possible mechanisms for the workings of anesthesia.
8) Dr. Joseph F. Smith Medical Library online , a useful source to search for information on medical related terms.


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