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How to Read a Compass

Don't Know How to Read a Compass? We'll Be Your Guide

Are you planning a trip to a national park? If yes, it may be a good idea to learn to read a compass just in case you need to, at any point of time, figure out your location and reach your destination.
Tulika Nair
Last Updated: Jan 18, 2019
Finding the right way
There may be a lot of people out there who will question the need to read a compass in this age and time when cell phones come laden with GPS applications and navigating technologies. But the fact remains that you never know when lady luck decides to play spoilsport and drains that battery or cuts those satellite signals.
In such a scenario one of the best equipment that will come to your rescue is a compass. It is imperative that everyone learns to use a compass because it is a skill that you should definitely possess. And even if you never use it, well as they say, no knowledge is bad knowledge.
An Overview
Before the compass was invented people used to navigate themselves at sea by using landmarks and the position of astronomical bodies. The problem with this method was the dependence of navigation on clear weather.
Map & Compass
According to the astronomer John Carlson, the first rudimentary form of a compass was devised by the Olmecs who used lodestone compasses as early as 1000 BC. This theory does not have many takers though, with most historians crediting the invention of the compass to the Chinese sometime around 1044 BC.
Compass close-up
The navigational device helps in pointing out directions by indicating the magnetic north. It does so because the magnetic bar of the compass always aligns itself to the lines of the magnetic field of the Earth.
Geographical map and a compass
It is important to know that the magnetic north as pointed out by the compass and the geographic north is not the same, nor is it coincident. It uses the concept of earth's electromagnetism.
The compass always points towards the magnetic north due to the magnetic force that is exerted by the forces under the Earth's surface. The magnet that is an integral part of the compass is attracted by this magnetic force which leads to the needle on the compass to point northwards.
There are few errors that can be caused by a compass. Generally the compass is stable in areas closer to the equator but as it crosses magnetic fields and moves towards the magnetic poles, the compass starts becoming more sensitive, and thus, the errors increase. Due to acceleration or deceleration of a vehicle also there may be errors caused.
Reading a Compass
There are directional indicators around the perimeter of the dial pointing out the directions, north, east, west, and south. These directional pointers split the compass into four divisions which can be divided again as the northeast, northwest, southeast, and southwest.
Navigational Compass
The circle is divided into 360 degrees with north being equal to 0 or 360 degrees, east being 90 degrees, south, 180 degrees, and west, 270 degrees. There is also an orientation arrow at the bottom under the needle.
  • Hold the compass in your hand and let it lie flat. Allow the needle to turn.
  • Now point the compass in the direction of the location you want to travel to.
  • Rotate the compass in a manner so that the end of the arrow that is pointed is aligned with the end painted red on the magnetic needle.
  • You can read the bearing as it shows in the index line.
  • The direction of the travel arrow should be pointing towards the location you want to reach. Walk towards it by first spotting it.
In this manner you will be able to ultimately reach your destination.