Using a Compass : Finding North

Why do I need to know which way is North?

Maybe you are following instructions. Maybe you want to know where the sun will rise (East) or where it will set (West). Or maybe you want to use a map to help you make your way. So it helps to know which way is North, because most maps are drawn with North at the top edge. Of course there are always exceptions. For example some French maps of the Pyrénees are drawn looking South. But generally you’ll find North at the top of the map. Still it’s always best to check by looking around the map, to see if you can find a “compass rose” like these…

A rose like one of these illustrations, will show you which way the top of the map points. We say it’s the way the map is: “oriented”. Once you know how to orient your map, you will immediately find it easier to know which way to go next… even on a city street. We’ll discuss this more in future posts.

Getting a rough idea

You can get a good idea of the rough direction of North using a simple compass. Here is an image of one from a popular brand, Suunto:

Centred in the middle of the circle is the compass needle.  One end is coloured deep red (pointing up the page) and the opposite end is coloured black. In other compasses they might be coloured red and white, or perhaps coated with a luminous paint for use in poor light conditions.

Traditionally, when the compass is held horizontally, and away from large metal objects or electronic devices,  the red end will point towards the North and the other end (perhaps  painted black or white) towards the South.

Good to know: The compass needle is mounted on very fine point, to allow it to rotate freely. Removing any hindrance to the needle’s rotation helps the compass to be as accurate as possible.

Compass card, courtesy of coastalnavigation.com

Sometimes the needle may be mounted on a “card” (like the one in this next illustration) so that it can also show the other “Cardinal Points”, which are E/east, S/south and W/west.

But the needle or card is usually also mounted in a special fluid, to dampen any wild swings, and help the needle settle down and point to the North quickly.

Unless you are living in the very far north, or the very far south of the world simply looking at a compass in this way, will give you a very good idea of the general direction of North.

Using a SmartPhone

Some modern smartphones will contain an electronic compass and the app stores of Windows, Apple and Android phones will have apps you can download to help you use it. Here’s one from Digital Mason for a Windows phone:

Electronic Compass App

You can see it looks just like a standard compass rose. North is marked off in red. If you hold the phone horizontal and rotate it, then the compass rose will rotate so that it continues to point to the North.

You can also see that this compass rose is a “card” that also shows not only the four main cardinal points, North, East, South and West; but also those in between: NE (north-east), SE (south-east), SW (south-west) and NW (north-east). The activities below will help you to get used to thinking about what these directions mean.

Calibrating: Smartphone compasses (sometimes called “flux gate” compasses) can be very easily influenced by other electronics and metal objects around them, so we have to recalibrate them to make sure they work. Mariners call this “swinging” a compass. If you need to calibrate your smartphone compass, then the app will tell you with a screen that looks something like this…

Activity

1. Take your compass, or the compass app on your smartphone and go outside, perhaps into your garden, or the road in front of your home. Make sure you are  away from anything that might cause interference; power lines, large metal surfaces (like a car) or any electronic or radio equipment.
2. Hold the compass  horizontally and flat and wait for the compass needle to settle.
3. Look down and along the red end of the needle. Now look up gently to see where the needle is pointing.  Make a note and try to remember, because that direction is generally the North.
4. Now looking towards the North, turn a quarter of a circle to your right and look in that direction. That’s East, and is roughly where the sun rises.
5. Turn back to look towards the North and now turn a quarter of a circle to your left. That’s West and is roughly where the sun sets.
6. Finally turn back to look towards the North, now turn around and face the opposite direction. That’s South, and is roughly where the sun will be, up in the sky, in the middle of the day.

Good to know: As the year progresses you may notice that the sun doesn’t rise and set in exactly the same place every day. In fact, the sun will rise and set in positions closest to the North in summer and in positions furthest away from the North in winter. But more on that in the future.

Next Steps

The next posts in The Outdoor Handbook will look in more detail at the compass and the compass in your smartphone:  To help you understand more of its features, how to describe a direction from where you stand, and how to make your directions more accurate.

Last edited: 27 August 2016.