Dead reckoning, bearing straight, finding your way in a whiteout. Whatever you call it, learning to find your way from a known position using direction and distance traveled is the best option for getting safely back to where you started.
The steps to accomplish this task are easier to learn than it may sound. Let's start with the basic components of a good orienteering compass. The compass should be attached to a clear rectangular base plate which can be rotated (the compass housing should rotate on the base plate).
Step 1 Use the edge of the compass baseplate and a pencil to connect where you are on the map to where you want to go (A to B on the photo). Measure that distance against the scale printed at the bottom of the map.
Step 2 With the compass baseplate aligned to the line you just drew, twist the compass housing until the orienting arrow aligns with map north. Ignore the needle. Where the direction-of-travel line intersects the rotating dial is the map heading - the direction you want to travel.
Step 3 Find the declination diagram in the bottom left margin of your USGS topo map. It looks like a little V (see photo below). It shows the difference in degrees between map north and magnetic north for that particular map. If magnetic north (MN) is left of map north, add the degrees of the declination to your map heading. If MN is right of map north, subtract the degrees of the declination from your map heading. HINT: remember "LARS" for "left add, right subtract".
Step 4 Twist the housing so it reflects the declination. You have your bearing, but don't trust it to memory. Write down the distance and magnetic heading for each leg.
Step 5 Follow the magnetic bering by holding the compass in front of you and rotating your body until the red compass needle sits within the orienting arrow. Pick out a small landmark ahead of you on the line of travel. Walk to that tree, bush, rock or whatever and maintain your pace count. Repeat the process until you've paced off the full distance.
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