Using a Compass
Parts of a Compass
Understanding the parts of a compass is essential for proper navigation.
Key Components:
- Magnetic Needle: The red end points to magnetic north
- Direction of Travel Arrow: Points in the direction you want to go
- Rotating Bezel: Marked with degrees (0-360°)
- Orienting Arrow: Aligns with the magnetic needle when taking a bearing
- Baseplate: Clear plastic base with a ruler for measuring map distances
Taking a Bearing
Step-by-Step Instructions:
- Hold the compass flat in your hand at chest level
- Point the direction of travel arrow toward your destination
- Rotate the bezel until the orienting arrow aligns with the magnetic needle (red end)
- Read the bearing (in degrees) at the index line
Following a Bearing
Step-by-Step Instructions:
- Set the desired bearing on the bezel
- Hold the compass flat in front of you
- Rotate your body until the magnetic needle aligns with the orienting arrow
- The direction of travel arrow now points in your desired direction
- Look up, identify a landmark in that direction, and walk toward it
- Repeat this process as needed to stay on course
Adjusting for Declination
Magnetic north and true north are not the same. The difference between them is called declination.
How to Adjust:
- Find the declination for your area (from a topographic map or online)
- For easterly declination: Add the declination to your bearing
- For westerly declination: Subtract the declination from your bearing
Remember: "East is least, West is best" (add for east, subtract for west)
Interactive Exercise
If your map bearing is 85° and the declination in your area is 10° East, what compass bearing should you follow?