Ok, I just sent this off to Cecil, but thought that I might try here as well:
A few years ago I talked to a woman who's car was broken into. She told me that the thieves broke the window with porcelain from a spark plug. She said that even a small amount of spark plug porcelain could punch a hole in a window when thrown against it. I wasn't sure about this, so I tried it on a junker car in my possesion. I broke an old spark plug, took a pebble sized piece of the porcelain and threw it against one of the windows. Sure enough, it poked a nice hole in the window with no trouble. "Wierd." I thought, and then forgot about it for a while. But recently I started wondering why that is, and if it would work on other types of glass (house windows, safty glass). I certianly don't want to try that, but I imagine that the type of glass and thickness would vary the results. What is it about spark plugs that make them good for this?
-Jeff
