# Sources of Magnetic Fields

Where do magnetic fields come from? For a long time, Western scientists thought it was simply something to do with certain kinds of rocks. Then one day, a physics teacher named Oersted was setting up a demonstration for a science lecture. He put out some compasses and some wires, and was surprisedso goes the story; other sources suggest that he expected this result that, when he sent current through the wire, the compasses would move. Apparently electric currents create magnetic fields.