Having got to know our compass last week on the Ordnance Survey blog today we’re going to look at how we use it to take a bearing. What you’ll need for this is an Ordnance Survey map and a compass.

First of all – let’s see what Simon King has to say about using a compass …

Did you get all that? Let me try and put it in simple step by step terms for you.

1. To start with you need to know where you are on the map (point A) and where you want to go to (point B).
2. Line up point A and B with either the side of your compass or one of the black lines running down the base plate, making sure that the direction of travel arrow is point in the direction you want to go in (so towards point B).
3. Now you want to turn the compass housing bezel so that the “N” on the bezel and the orienteering arrow are point to grid north (the top of the map). To help do this – make sure that the orienteering lines are lined up with the easting lines on the map.
4. Now you can lift the compass off the map.
5. Look at the index line – this has given you your bearing from the map. We now need to add the 2° to this to make grid north match magnetic north.
6. Stand up with the direction of travel arrow pointing directly in front of you. Walk around in a circle until you have the compass needle lined up with the orienting arrow.
7. Look up, following the direction of travel arrow and pick a natural feature or landmark that is directly in line with where you are looking / where the direction of travel arrow points to.
8. Walk towards this landmark and once there check your bearing, pick another landmark to walk towards. Repeat this until you reach your destination (point B).

If you’re unsure about using a compass the best thing to do is get the map of an area you know really well, perhaps somewhere local to where you live, and is somewhere that you wouldn’t usually need a map to get around. Take yourself off for a walk, using the map and a compass to navigate your way. This way you shouldn’t get yourself lost (as it’s an area you know really well) and you can check that the direction you think you should be traveling in matches what the compass is telling you!

Having run map reading workshops for Ordnance Survey over the past couple of years there are a few common things where people tend to go wrong in compass navigation:

• Make sure that the direction of travel arrow is pointing in the direction you want to walk in – it’s called the direction of travel arrow for a reason!
• In step 3 above – always make sure that the orienting arrow is pointing to grid north (the top of the map) rather than grid south (the bottom of the map) – even if you are walking south – the orienting arrow still needs to point north.
• Unless you always want to walk due north – follow the direction of travel arrow rather than the compass needle.
• Make sure that the landmark you pick is a feature on the landscape that is not liable to move – pick a tree, gate post, gorse bush or boulder for example rather than a cow, sheep, person or bird!

What tips and hints do you have for those starting out in compass navigation?