Cardinal marks, introduction

Cardinal marks indicate where the mariner may find navigable water.
These marks are used in conjunction with a compass.
Here we have four quadrants,: North, East, South, and West.
The danger in the middle is the point of interest.
From the point of interest we bound
the north quadrant by the true bearings, NW-NE
the east quadrant by the true bearings, NE-SE
the south quadrant by the true bearings, SE-SW, and
the west quadrant by the true bearings, SW-NW.