.Spontaneous Human Combustion
http://www.abc.net.au/science/k2/moments/gmis9847.htm
One of the really bizarre, and still unexplained, happenings is the phenomenon called "Spontaneous Human Combustion". Apparently, once every two years or so, a human being bursts into flames - for no apparent reason. It's very important to emphasise that in true Spontaneous Human Combustion (if it really exists) the human body bursts into flames without touching an external flame or source of heat. Often the whole body is reduced to ashes.
Now I have to say, right at the very beginning, that I am still not convinced that Spontaneous Human Combustion really exists - simply because nobody has been obliging enough to burst into flames before an expert audience of forensic pathologists.
There have been about two hundred reports of Spontaneous Human Combustion over the last four hundred years. They are roughly equally divided between male and female. They can be any age between four months, and one hundred and fourteen years. Some victims were drunkards, while others were teetotallers. Some had been under-weight, while others had been overweight. There simply is no obvious pattern.
Charles Dickens described Spontaneous Human Combustion in chapter 32 of Bleak House, when he decided to get rid of one of his characters in the rather convenient way of having them burst into flames. Charles Dickens was convinced that Spontaneous Human Combustion existed. In the preface to Bleak House, he describes how he studied the subject carefully, and found about thirty cases, he claimed, of Spontaneous Human Combustion. So he decided to use it in his book.
A typical report was that of Ann Martin in Philadelphia in 1957. It is said that only her feet and the top of her trunk remained intact, with everything in between - just ashes. Newspaper, only 60 cm away, was completely untouched.
Now in a house fire, the extremities of the body (hands and feet, arms and legs) are burnt to ashes - but the central trunk of the body is always left behind. A forensic pathologist can look at the bones in the pelvis, and say that the person was a man or a woman, young or old, and if they were a woman - they can say if she'd had children. The central trunk is always left behind in a house fire. But in spontaneous human combustion (if it really exists), the central trunk is consumed to ashes, while the hands and feet are usually left untouched.
If you want to burn a corpse in a crematorium, you need a lot of heat. What they do is burn the body at 1200oC for an hour and a half, and then at 1000oC for another one and a half hours. Even then, they don't get just dust and ashes but bone fragments - they have to grind these down with a mortar and pestle. In even the worst house fire you won't get a temperature above 850oC - so where does the energy for this human fireball come from?
Well, if we adults want to generate heat, we have to move a muscle or a bunch of muscles. Either we pump iron and get warm that way, or else we run around the block, if we are feeling athletic. If we are pretty lazy, we will just sit there and shiver. Either way, if we want to generate heat we have to move muscles.
But babies, especially new-born babies, in the first few months of their life have a unique trick for generating heat. They have a substance called brown fat, and this brown fat can turn energy directly into heat without having to move a muscle. In general, adults don't have brown fat. Maybe, in Spontaneous Human Combustion (if it really does exists), a person develops some brown fat, and then has a abnormal runaway reaction that generates enough heat to set the body alight.
But we really don't know. The closest medical phenomenon that we have is Malignant Hyperthermia. In this rare (and often fatal) disorder, under the right circumstances, a person can have their body temperature get as high as 47oC. But that's a long way from burning a body.
I really didn't believe in Spontaneous Human Combustion, until I read a report in the New Scientist by a retired Scenes-Of Crime Police Officer, in Gwent, in the United Kingdom. He described a case which seemed to be a classic Spontaneous Human Combustion - but he couldn't describe as such in the official report, or else he would have been laughed out of the Police Force.
So as for me, I will just remain vaguely dubious, until a really well-documented case turns up.