How to use the compass?

How to use the compass, using the compass, you can make the orientation of the map consistent with the actual terrain, and find out where you are now and the orientation of the destination you are looking for. The compass must be held horizontally, away from the following items to avoid confusion of magnetic needles: the compass should be away from barbed wire10m, 55m from high-voltage lines, 20m from cars and airplanes, and10m from magnets such as magnetic containers.

Compass, called Sina in ancient times, is mainly composed of magnetic needles installed on the shaft. Under the action of natural geomagnetic field, the magnetic needle can rotate freely and keep in the tangential direction of magnetic meridian. The south pole of the magnetic needle points to the geographical south pole (magnetic north pole), and the direction can be distinguished by using this property.