Originally a rite of spring, and performed in many parts of the world, including India, Greece, South Africa and California, fire-walking is most popularly associated with Polynesia, especially the Society Islands and the Fijian Islands. In 1901, engineering scientist Professor S.P. Langley from the Smithsonian Institution witnessed a classic demonstration of fire-walking in Tahiti, performed by a native priest from the neighboring Society island of Raiatea. The demonstration feature a trench measuring 6.4 meters long, 2.75 meters across and about 0.6 meter deep, filled with radiant basalt rocks piled on top of blazing logs. The priest and several of his acolytes strode steadily but very briskly over this trench four times, with no resulting injury. Yet when Langley levered one of the rocks out of it and into a bucket of water, the water churned and frothed so violently that a considerable quantity boiled over the sides.
In 1950, Dr Harry B. Wright of Philadelphia observed a similar fire-walking ceremony, performed annually by the people of Mbengga, one of the smaller Fijian islands. Before the fire-walk began, Wright examined the feet of the participants, to determine whether they had been treated with any protective substance, but he found no evidence to suggest this. Paradoxically, he did discover that although these people experienced no injury or pain whatsoever when walking across their trench of fiery rocks, their feet displayed normal sensitivity to the approach of a lighted cigarette and also to a pinprick.
Many other fire-walking demonstrations have been closely monitored by scientists, who confirm that the walkers’ feet have not been treated in any way, that the temperature of the rocks has been shown to be as high as 800 degrees Celsius, and that even untrained Westerners can successfully perform fire-walking – as long as they firmly believe that they will not be harmed by the fire. How can this astonishing accomplishment be explained?
The answer seems to be a subtle blend of several different interacting factors. The soles of the feet of native fire-walkers are very thick and calloused, which would reduce injury. Moreover, during an investigation in 1935, the English psychical researcher Harry Price noted that physical contact between the entirety of each of the walker’s feet and the fiery rocks lasts no more than half a second at a time (hence actual contact by any specific part of the foot is even less). Thus there is insufficient time for the feet to be burnt, especially if the total length of the walk is itself brief. Tellingly, after watching some local people undertake a three-second fire-walk at the 26th annual meeting of the Ceylon Association for the Advancement of Science, Dr Carlo Fonseka challenged them to perform a 30 second fire-walk: they all declined to do so.
As Professor Jearl Walker, a physicist at Cleveland State University in Ohio, has pointed out, a phenomenon very relevant to fire-walking is the Leidenfrost effect. This is the process whereby a liquid exposed to intense heat will instantly form a protective, insulating boundary layer composed of steam. It allows us all to indulge in a very simple form of fire-walking – when we snuff out a candle with a wet finger. And sure enough, many observers at fire-walking ceremonies have noted that the walkers often moisten their feet before performing the walk.
Psychology is also most important. Westerners performing fire-walking after convincing themselves that the glowing rocks will not harm them not only escape injury but also experience feelings of euphoria. This suggests and enhanced secretion by the brain of endorphins – natural pain-killers that impart an elevated sense of happiness and well-being.