Chapter 35. Compass Points
The compass was invented in China sometime before 200 bce. The traditional universal agreement was that we have four cardinal directions (north, south, east, and west). After that, there were a lot of different ways to slice up the ordinal (i.e., noncardinal) directions.
But things are tricky. True north (i.e., the location of the Earth’s North Pole) does not match the magnetic north (i.e., where a magnetic compass points). In fact, the magnetic force lines are not regular or stable. They vary over time. This is why Renaissance buildings in Europe that were set in position by a magnetic compass are oriented a few degrees off a true north-south alignment.
Today, we have all settled on a system that uses 360° in a clockwise ...
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