Here at Guru, we have a burning passion for straight-talking science. And there’s no one more straight-talking than our Sceptic Guru, Daryl Ilbury. Join him as he explores the world of spontaneous human combustion, and discovers there’s some truth in the old adage ‘if you can’t stand the heat, keep away from the fire…’
“With the fire burning in his loins, Eduardo grasped Elizabeth, and passionately crushed himself against her heaving bosom”. This may sound like a line from a trashy romance novel – and that’s possibly because it is. Of course, it’s purely metaphorical: if Eduardo’s loins were indeed ablaze, I doubt he’d have anything remotely passionate on his mind. The only vaguely scientific explanation for the burning sensation in Eduardo’s loins is something a shot of penicillin could have sorted out. Enough said.
A burning sensation in the body is nothing new. It’s simply a way we describe a localised area of pain or discomfort – ‘heartburn’ being a classic example (even if it’s nowhere near the heart). However, the idea that the human body can somehow just burst into flame is nonsense. Of course, this doesn’t stop people peddling it as real – and there’s even a term that disciples of the mysterious and unexplained use to describe it: spontaneous human combustion, or SHC. It sounds scientific, but it isn’t. History is dotted with stories that have been held up by believers as evidence of SHC. As recently as 2010, a 76-year-old Irishman called Michael Faherty was found burned to death under what were termed ‘mysterious circumstances’. In fact, the coroner, Dr Ciaran McLoughlin, could find no adequate explanation for his death. However, the fact that his burned body was found next to an open fire may hold some clues…
SHC: all smoke and mirrors?
When was the last time you were watching Strictly Come Dancing and your beloved Aunt Milly suddenly burst into flames, leaving a nasty burn mark on your faux leather sofa? Can you ever remember standing in a supermarket queue with a cabbage in your hand only to watch smoke start to rise from the shop assistant’s ears before seeing her doused with water by a passing colleague?
Exactly. Incidences of supposed SHC invariably involve elderly people living alone – people more likely to suffer heart attacks or display absentminded behaviour, like sitting too close to heat sources. They are also more likely to be immobile due to ill health and therefore be unable to escape should their clothes catch fire.
All it takes in such cases is a heart attack, a dropped cigarette, or a nylon nightgown too close to an electric heater, and a person can burn to death. Such deaths are normally termed ‘unsolved deaths by fire’, even if no obvious cause can be found.
It’s worth pausing to reflect on what this means: even if it had been destroyed in the ensuing blaze and was never found, an external cause is always considered the most likely. That’s because an internal cause is virtually unimaginable. And yet the idea that someone can spontaneously burst into flame because of a fire that started from inside them is a central element to SHC.
Money to burn
The reason why spontaneous combustion doesn’t happen can be explained using an experiment that was part of my repertoire when I used to present science shows – lighting a banknote and watching it burn, without it actually burning. Such an experiment can be done by soaking a banknote in a mixture of clear alcohol and water and then lighting it (don’t try this at home, kids). It is the alcohol that burns, not the money – the reason being that the money, kept cool by the water, doesn’t get hot enough to burn.
The human body, as any student of biology will tell you, is mainly made of water, so it could never get hot enough to just start burning. This doesn’t mean the human body can’t be burnt – cremation really happens, after all. It just means that very high external temperatures are needed to raise the body temperature enough for it to start burning – and this explains why a crematorium needs to operate at between 870 and 1000 degrees Celsius.
This is where our story gets a little icky (or should I say ‘wicky’). Once a body starts burning, it provides its own fuel: human fat. Human fat contains a large amount of energy by virtue of it containing long hydrocarbon chains (chains of carbon atoms with hydrogen atoms sprouting from them). As a result, it burns like the wax of a candle. Should someone start burning, their fat can melt and seep into their clothing, which then acts like a candlewick (morbidly enough, it’s a phenomenon called ‘the wick effect’). So, should someone start burning from the outside, nature will keep them ablaze. (Well what were you expecting from a story about spontaneous combustion? Pictures of puppies and butterflies?)
However, wherever science is ignored, pseudoscience abounds. And so it is that accounts of spontaneous human combustion still get enthusiastically bandied about on websites dedicated to the paranormal – my personal favourite being Defenceless village incinerated by UFOs.
If, you wish to delve further into these stories in the pursuit of dismissing pseudoscience (why else?!), perhaps you should read Ablaze! The Mysterious Fires of Spontaneous Human Combustion,by Larry E. Arnold, the self-proclaimed “world’s foremost expert on exploding people”.
He used to be a bus driver, so I guess he knows what he’s talking about.