Today on the radio program Pulse of the Planet, Danforth explains the physics of fire walking by comparing it to putting your hand in an oven in which a cake is baking at 500 degrees Fahrenheit (260 degrees Celsius). (The National Science Foundation partially funded this article to serve as a complement to the Pulse of the Planet radio program.)
"If I open the stove and reach in with my hand and touch the air inside the stove, I don't get burned, because my hand is dense and heavy compared to the air, and so the air doesn't heat up my hand. ... ," Danforth says in the radio program.
Touching the metal inside the stove, however, would immediately lead to a burn, because metal, which is much denser than the air, is a good conductor of heat.
The cake, Danforth said, has the consistency of the coals in a well-prepared fire walk. Even though the cake is hot, it can be touched for brief periods without causing a burn.
State of Mind
Tolly Burkan is the founder of the Firewalking Institute of Research and Education in Twain Harte, California. He promotes himself as the creator of the U.S. fire-walking movement, which he says dates to 1977.
"I was the first person to come along and make it available to John Q. Public by offering fire-walking classes that anybody could attend," he said.
Burkan dismisses the idea that the low conductivity of coals is a reason that fire walking is possible. As evidence, he points to an incident in which members of his institute successfully walked repeatedly on a heated metal grill without getting burned.
According to Burkan, the basic physical principle behind fire walking is the same that allows an egg to boil in a paper cup when placed atop red-hot coals. The boiling water keeps the cup at 212 degrees Fahrenheit (100 degrees Celsius)hundreds of degrees cooler than paper's burning point.
Burkan says that circulating blood likewise keeps the flesh on a fire walker's feet from reaching its burning pointas long as the walker is relaxed enough to allow strong blood flow and as long as the walker keeps walking.
"What controls [the ability to fire walk] is more than physics, it's your state of mind," Burkan said.
Willey, the Pittsburgh physicist, said such mind over matter theories have nothing to do with why fire walking is physically possible. He allows, though, that self-confidence is required to take that first step.
"You've got to believe you're going to be OK, otherwise you wouldn't do it," he said. "But what your mind-set is has got absolutely nothing to do with whether you're going to burn or not."
Danforth, the Bates College anthropologist, said that scientific explanations do not "debunk or diminish or invalidate the value of the ritual."
"[Fire walking] can have the power to affirm one's life. It can change lives, give confidence, all kinds of things," he said.
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