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How to use a compass to take a bearing

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A useful function of a compass is to identify a landmark or destination on a map, by noting its direction from your current position. For example, you want to know the name of the village you can see in the distance. Or you may want to log your travels by noting your direction of travel at points along the trail. Perhaps you may want to make notes for following travellers about what can be seen from a specific location, in a particular direction. You can do these things by 'taking a bearing'.
What you'll need: 
A compass (the plastic see-through hiking type is recommended)
A map (In the UK, Ordnance Survey maps are recommended for walkers)
A pencil (optional)
An eraser (to rub out your pencilling later)
A ruler (optional)
1: 
Point the arrow on the base plate of the compass at your chosen landmark or in the direction you want to travel/make a note of.
2: 
Turn the circular housing until the lines and arrow in the bottom are aligned with the needle (red end pointing along arrow).
3: 
Read the number at the marker line under the ring of numbers, which is in line with the arrow on the base plate. This is your bearing, and can be noted in conjunction with the general geographical direction, e.g. 40 degrees North East.
4: 
If you want to find a landmark on your map having taken a bearing from it: Put the compass on the map with a long side of the base plate against your current location (assuming you know where you are!) and the lines of the needle housing aligned with the vertical grid lines of the map.
5: 
(optional) Make sure the map is pointing North by turning everything until the red needle is aligned with the arrow in the circular housing. This just makes it easier to know which way to follow the line in the next step.
6: 
Follow the line along the long edge of the base and extend it across the map. Use a pencil and ruler if needs be and to hand. If you've done Step 5, you should be drawing towards the actual landmark; look up and check!
7: 
Looking at the features on the map along the line from your location, you should be able to spot the landmark.
8: 
To more accurately pinpoint the position of a landmark, should you so desire, carry out steps 1 to 6 and draw a line on the map before continuing your journey for at least a mile or so. Then repeat the steps from a new viewpoint and draw another line.
9: 
If not already crossed, extend the two lines until they do so. Where they cross on the map should coincide with the location of the landmark you've been looking at, and you can now identify it.
10: 
If you want to know how far away your landmark is, and you know how far you travelled between the two measuring points, you can use the bearings/angles to calculate how far away it is. But that'll be for another article...
Conclusion: 
Triangulation is the basis for this straightforward exercise which could be useful in all sorts of situations. Happy trails!
Tips: 
Be as accurate as you can when taking your bearings.
Look slightly either side of the lines you draw (wider as you get farther from your current location) to cater for slight innaccuracy of the bearing.
A 'Mirror Compass' is more accurate for these purposes as it can be 'aimed' at the target at eye-level while still being able to see and rotate the dial/housing.
Warnings: 
Magnetic North, as indicated by a compass, is slightly adrift of True North and Grid North (map vertical) and is always shifting by tiny amounts. Good maps will provide information to allow for this adjustment. In general though, over short distances this issue is not one to worry about, although is worth bearing in mind when searching for landmarks having taken a compass bearing.

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