North line
Also called: North arrow, Direction symbol · Topic: Maps and Map Scale · NCERT: Class 11, Ch 1 "Introduction to Maps"; Class 11, Ch 5 "Topographical Maps"; Class 12, Ch 3 "Graphical Representation of Data"
Meaning
The north line is the arrow or symbol on a map that shows which way north lies. North is the base direction, or zero direction. Every other direction is measured from it. That is why every map must show a north line. Without it, the reader cannot turn the map the right way (orient it) or tell east from west.
Example
A Survey of India toposheet of the area around Delhi has a north arrow in its margin. The reader lines the map up with this arrow. Then they can see which way the Yamuna flows and which places lie to the east, west or south of the city.
Don't confuse with
- Magnetic north: the direction a compass needle points. It is slightly different from true (geographic) north, which points towards the North Pole.