The document discusses the compass needle and how it was discovered. It explains that in 1820, Oersted discovered that an electric current could deflect a compass needle, showing the link between electricity and magnetism. The compass needle functions by indicating magnetic north due to its magnetic properties. Instructions are provided on how to make a compass needle by rubbing a needle or pin on a magnet, attaching it to Styrofoam or plant stalk, and placing it on water where it will orient itself to point north.