Few things are as cringe-inducing as watching someone shove pieces of metal into his face. The human blockhead is essentially just that. The performer puts a long piece of metal, like a nail or a screw driver, into his nose and then pushes it deep into his skull, presumably to dazzle prospective employers at a job interview.
The drill counts as a personal reference.
But for a well-practiced professional, this trick isn't very painful or even all that dangerous (again, FOR A WELL-PRACTICED PROFESSIONAL). As it turns out, the human skull has a lot of empty spaces inside it.
Your nasal cavity, for instance, is a large empty space that extends pretty far back into your head. The ceiling of this cavity is about even with the top of your nose, which means that sometimes you might have to turn your nostril upward before you shove a nail in there.
... who figured this out?
Your nasal cavity is ribbed with small grooves called conchae that hold mucus, which allows a smooth, lubricated insertion for whatever lucky object you've decided to ram into your face. Some performers will even go so far as to use a hammer to literally drive nails into their skulls, which you may notice is a task typically left to serial killers, and is something that can backfire spectacularly if the length of the nails involved has been misjudged.
"It's hammer time! But seriously, this nail is lodged about a centimeter in my brain and I can't remember how to breathe."
If American cinema is to be believed, there is a bed of nails on every Turkish street corner, with a dude in a loincloth lounging on it. Why? Because the people there are exotic and magical and can do things no simple Westerner can do!
But let's see this guy kick our asses at Call of Duty.
Understandably they tend to draw a crowd, because a bunch of nails clustered together isn't the kind of surface that begs to be slept on.
"I'd sit up but I'm afraid it'll nail my scrotum to my taint."
But it isn't a miracle that people can lie on them without bleeding out like a sprinkler head. It's one of those cases where more nails equals less danger. If you don't know what we mean, offer the death-defying nail bed guy a chance to lie on just one vertical nail. He'll decline.
But stick bunches of nails together, only an inch or so apart, and you're in business. Because you're distributing your weight over hundreds of nails, you're not putting much weight on any one point. Certainly not enough to let the nail punch through your skin. As long as you spread out the weight, you can lie there for hours without getting a scratch. It's not even all that uncomfortable.
But you have to be careful getting on and off the bed, because once you put all the weight of your body onto just one hand or foot or elbow, you'll suddenly realize that these are goddamned nails here.
He's in time out.
In ancient times, fire walking was a noble tradition practiced as a part of religion and in rites of initiation. These days, it's used for team-building exercises, usually trying to teach some lesson about courage and the power of positive mental energy or some shit.
There's no fakery as far as the fire is concerned; the hot coals used for fire walking usually exceed 1,000 degrees Fahrenheit. But thanks to science you, too, can walk barefoot across the coals without getting burned.
First off, you'll notice they often wet the area right before you start on the coals, or at least do it next to wet grass. If your feet are moist, you have the Leidenfrost effect protecting you, which occurs when you have a layer of liquid between an object and a major heat source. The water creates an insulating vapor to greatly reduce heat transference, essentially encasing your feet in a fireproof mist.
Seriously DO NOT try this at home you stupid little fucks.
Considering that you are basically water and bits of flesh, you can also depend on the principles of heat capacity. Water has a very high heat capacity, while the coals have a very low heat capacity. Therefore, the temperature of your feet will change less than that of the coals as you walk across them. And because of water's high thermal conductivity, rich blood flow in the foot can carry the heat away, diffusing it upward. This is all fancy talk to say that your very watery body is able to put up a shield (of science) to briefly protect your feet from the scorching heat of the coals.
Make no mistake: If you stand on hot coals, you're going to burn the shit out of your feet. Conversely, you can't run top speed across them because that'll cause your feet to sink deeper into the coals with each step (think of the deep footprints you dig when running through sand, for instance), which will also burn the shit out of you. The key is to lightly and quickly step across them.
Also, if you don't let the coals burn down long enough before you try walking over them, that's also bad news. The coals are usually just burning cinders of wood, and wood has moisture in it. If the water inside the coals hasn't had enough time to evaporate it counteracts the difference in thermal conductivity we discussed earlier, and once again you're screwed.
Also, you could try just not doing it.
For more ill-advised do-it-yourselfs, check out Nectar of the Broke: The World's 5 Worst Ways To Get Drunk and 7 High Tech Products And Their Cheap Ass Ingredients.
And stop by Linkstorm to learn how to shove your whole fist in your mouth.
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