Using A Compass Alone
No map
The purpose of using a compass NOT in conjunction with a map would be to hold your course while traveling towards a distant landmark.
For example, you may be able to see your destination (or a prominent feature you know is close to or on the way towards your destination) while standing on a high ridge. But that feature may be many miles away, and once you leave your high-point, perhaps you’d lose sight of it. By taking a bearing and determining your direction of travel with your compass, you can use that bearing to continue in the right direction once you’re underway.
First, sight the feature along the direction of travel arrow on the base plate of your compass, keeping the compass horizontal while doing so.
While keeping the feature object on the line, turn the compass dial until the red end of the magnetic needle is pointing in the same direction as the north/south arrow on the bottom of the capsule.
Re-check you bearing often. If you want to know your bearing in degrees, just read off the number on the dial that’s lined up with the index mark.
Now that you have your direction of travel — a bearing — you can begin to follow it. To do so, choose a prominent target in that direction — it may be a distinct tree, a boulder, a post, anything you can keep track of and recognize even if you look away from it — and walk towards it without looking at your compass. When you get to that target, get your bearing again, choose a new target, and repeat.
Using A Compass WITH A Map
Also known as the craft of orienteering
In this next section, we’ll go over:
1. Orienting your map to true north
2. Obtaining a travel direction from a map
3. Using an intersection to determine the location of a distant feature on a map
4. Using resection to determine your exact location on a map
5. Using the compass as a protractor
Orienting A Map To True North
To properly read a map in the field, you should first orient it, meaning that the details on the map should correspond to the landscape. And you should keep your map oriented while traveling along your route.
To orient your map, first find true north. Here’s what you do:
1. Set the compass bearing to north at the index mark.
2. Next, lay the side edge of the compass along the map edge (or neat line). The direction of travel arrow on the base plate must point north on the map.
3. Keep the compass in this position while rotating the map and compass together until the magnetic needle is aligned with the orienting arrow. This is called “boxing the needle.”
Your map is now oriented to true north. Now take a look at your map and then at what’s around you and see that it makes sense.
Obtaining A Direction Of Travel With A Compass
To reach your desired destination
The steps are as follows:
1. First, place the compass on your map so that the long edge of the base plate connects your starting point with your destination. Of course, the base plate likely will not be long enough to actually connect these two points, but an extended line drawn along this edge should connect the two. You can use a pencil to actually draw this line on your map.
2. Next, make sure that the direction of travel arrow is pointing from the starting point to the destination. In other words, make sure the compass isn’t “upside down” and pointing from your destination to your current location or starting point.
3. Now, hold the compass firmly against the map to keep the base plate steady and, with the other hand, turn the dial until the permanent north/south lines in the center of the dial are parallel with the magnetic meridian lines on the map. Check to be sure the north/south arrow on the bottom of the capsule points in the same direction as that marked with an “N” at the top of the magnetic meridian lines.
4. Next, hold the compass out in front of you, making sure to keep the base plate horizontal and the direction of travel arrow pointing straight ahead.
5. Rotate your body until the north/south arrow lines up directly under the magnetic needle. Remember, this is called boxing the needle.
6. The direction of travel can now be read along the direction of travel arrow.
FOLLOW THE BEARING:
Just as described above under “Using A Compass Alone,” choose a prominent target in that direction and walk towards it without looking at your compass. When you get to that target, get your bearing again, choose a new target, and repeat.
Periodically check to be sure that the compass dial didn’t get turned as you were walking and has not deviated from the direction of travel that you’d set while your compass was on the map.
Also, re-orient your map from time to time and look around to double-check your progress.
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