Feb 07
Who first used a compass?
Hundreds of years ago Chinese sailors used pieces of magnetite, made into needles, to help them find their way if they were lost. A piece of magnetite, or a bar magnet, when freely suspended, generally comes to rest pointing in a north-south direction (a compass needle is a magnet). The Earth is like a giant magnet and behaves as if there is a huge bar magnet in the centre.
Posted by Jay Roberts at 04:36 AM | Permalink
