Fortunately for travelers, the earth behaves as if it were a gigantic magnet. From natural magnetic rock called
"lodestone", early mariners made a compass that enabled them to find the direction of magnetic north.
Still today compasses have a magnet. One end always turns towards magnetic north. So, wherever you are, you can
use a compass tell the direction.
A compass on a map (also called a compass rose), like a real compass, shows the direction. Most arrows show north
on the map but there are exceptions. By tradition maps are drawn so north is at the top of the page. Some
cartographers in New Zealand and Australia dislike this arrangement as it shows these countries to be at "the
bottom" of the world. They make their maps with south at the top of the map sheet. In olden times, the
compass rose was an opportunity for the cartographer to show their artistic skill. Thus, on ancient maps, the
compass rose is often quite decorative. It's also useful to fill the empty spaces on the map.
The one shown above is from a world map made in 1375 (the Galapagos Islands had not been discovered!). On modern
maps the designs are less elaborate since the cartographer aims for clarity.
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