The ancient Chinese made a directional compass by heating a thin iron shard or needle in a fire until it was red hot. They then placed the red hot needle on plate to cool, being sure that it was aligned north and south. Once cool, the needle can be used as a compass by floating it in water. One method the Chinese compass makers used was to place the needle on a flat piece of cork, which was then placed in a bowl of water. The earths magnetic field caused the cork and needle to turn until it was aligned north and south.
Of course, using this method for making a directional compass you need to know beforehand which way is north. But once you have that figured out, you can take your homemade compass into the wilderness and survive with confidence in being able to find your way.
Poster Comment:
Interesting.