fire
okay. suppose you're a boy scout out in the middle of the woods with nothing but your wits. and your flashlight. can you start a fire? heh. yeah okay. man v wild aside. i was looking at parabolic mirrors for a solar oven. and one website pointed out that it does the opposite of what a flashlight does. and light bulb. i realized i already had a parabolic mirror i could play with. so i grabbed some matches and some dry tinder and some newspaper and headed to the backyard. i disassembled the flashlight and stuck a match in the hole where the light bulb used to be. i originally thought that the plastic lens cover would generate higher temperatures. something about keeping the heat inside. and not letting the wind take it away. but no. nothing happened until i removed the plastic cover. then fwoosh! the match head lit. and the parabolic mirror was all covered in schmootz. apparently the plastic absorbs significant amounts of non-visible electromagnetic energy. at least enough to make the difference between smoke and fire. unfortunately, the match was the only thing that would actually light. we could char everything to ash. but it never actually caught. maybe if our boy scout had a really big flashlight he could have a fire too. otherwise, he's gonna be rubbing sticks.