If you listened to our recent Halloween story "Haunted," and you're still skeptical of our skepticism about spirits talking through flashlights, this is for you.
If you have no idea what I'm talking about, go listen to the story here
After I first heard Dennis’ story, I poked around on the Internet, looking for someone to explain how a flashlight could communicate with the dead. A bit of googling led me to a 21-minute-long video on YouTube that breaks down the particulars of what are known as "flashlight sessions."
The video was made by a man in Germany named Burkhard Reike. When I called him up, I was greeted with the most incredible sound I have ever heard.
Once out of his cocoon, Burkhard told me this started for him when he was watching the ScyFy show “Ghost Hunters” (I’m assuming you get the gist of the show from the name). Over and over, these ghost hunters would pull out flashlights, ask questions into the air and then - just like in Dennis’ story - the lights would flash on and off.
At first Burkhard thought, eh, they're probably just tapping the table or some sly trick. But then he noticed something: all the different ghost hunters were using the exact same flashlight. The mini-Maglite, two-cell AA, with an incandescent lightbulb.
So Burkhard bought a couple, brought them home, and took them apart. Now, the thing about these flashlights is that to turn them on or off, all you have to do is screw or unscrew the top of the flashlight. When you do this, two tiny bits of metal come into contact with each other. When they're touching, the electrical circuit is open and the light is on. When they aren't, the circuit is broken and the light is off. Here's an illustration of the inside of the flashlight from Burkhard's video (contact point is on the right-hand side, in yellow):
(Photo Credit: Burkhard Reike) Burkhard ran through a dozen or so trials and experiments, five weeks worth, and found that this whole trick comes down to one part of the flashlight, the reflector. It's the dome-like mirror that surrounds the light bulb and focuses all that light. And here's how it works:
When you turn a flashlight on, the bulb generates a bunch of heat and the reflector starts to get really hot. As it gets hotter and hotter, it starts to expand, getting bigger and bigger. Then, if you want to ask some ghosts questions, what you do is you unscrew the top of the light JUST enough so that the light goes off. Now, because the light is off, the reflector starts to cool down and contract until it pushes one tiny piece of metal into contact with the other tiny piece of metal and … BOOM! The light bulb goes on. With the light back on, the reflector gets hot again and starts to expand … and expand … until it pulls the metal pieces apart again. And the light goes off. Then the reflector contracts, and so on.
Burkhard used a microscope camera and math to figure out that the expansion and contraction of the reflector is basically like turning the head of the flashlight 3 degrees. Cool detail, right?
But, I should say that it gets way more complicated than that - there's oxidization, fritting, molten metal - but the point is, as Burkhard said, "this is by definition something that is normal and not paranormal."
If you want to dive into the deep end, check out his explainer video. He's a good man and thorough.
Kielty,M. (2014, October 30). Explaining the flashlight sessions [Web blog post].
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