A few months back I was browsing twitter when a tweet crossed my eye. It was written by a survival training company and it said that it was impossible to start a fire with water. The writer was referring to a recent survival show episode where the co-host supposedly did just that. I saw the episode and admit that it was a bit suspicious. So I went and did research on the physics.
It turned out the science was there (as I vaguely remembered from my grade 11 and 12 physics class). Light can refract through water and depending on the shape of the vessel can be redirected. Theoretically, it was possible if you could get the light to focus enough to create a hot spot (like using a magnifying glass to start a fire).
Back to twitter. After a somewhat heated debate (he later removed all his tweets from twitter) I took him up on the offer to try it, prove it and video it. I took two continuous shots from two different perspectives. I mixed them together, but each shot shows the clear focusing of light and smoke coming off the paper.
I was able to get a coal and that’s enough to prove that this method can be used to start a fire. Take a look at the video I put together and try it yourself. I’d love to see a video response from somebody trying it.
What you’ll need is a piece of plastic wrap used for food, and water.
Pour the water into the plastic.
Close the plastic together at the top.
Twist the bubble of water until it is sealed.
Continue twisting until the bubble is firm.
Take it outside on a clear day (it’s easiest when the sun is directly overhead).
Manipulate the plastic bubble until the light passing through the bubble focuses into 1 point.
Put tinder where the focal point is and wait till it combusts. *tip: the darker the tinder, the less light is reflected and the easier it is to create a coal.