Map and Compass Checklist

 

By Mark Sembrat

Do you have the hang of using a map and compass? Run through the whole procedure.  Remember the following.

  • Never use the magnetic needle or the declination arrow when measuring or plotting bearings on the map.
  • When taking or following a bearing in the field, always align the pointed end of the declination arrow with the north-seeking end of the magnetic needle.

Orienting a Map

  1. Set to 0 or 360 degrees
  2. Place compass on the map with the direction-of-travel line toward the north on the map.
  3. Turn the map and compass together until the north-seeking end of the compass needle is aligned.
  4. Compare information on the map with the field topography.

Taking (measuring) a Bearing in the Field

  1. Hold the compass level in front of you and point the direction-of-travel line at the desired object.
  2. Rotate the housing to align the declination arrow with the magnetic needle.
  3. Read the bearing at the index line.

Plotting (following) a Bearing in the Field

  1. Set the desired bearing at the index line.
  2. Hold the compass level in front of you and turn your entire body until the magnetic needle is aligned with the declination arrow.
  3. Travel in the direction shown by the direction-of-travel line.

Taking (measuring) a Bearing on a Map

  1. Place the compass on the map, with the edge of the base plate joining the two points of interest.
  2. Rotate the housing to align the compass meridian lines with the north-south lines on the map
  3. Read the bearing at the index line.

Plotting (following) a Bearing on a Map

  1. Set the desired bearing at the index line.
  2. Place the compass on the map, with the edge of the base plate on the feature from which you wish to plot a bearing.
  3. Turn the entire compass to align the meridian lines with the map’s north-south lines. The edge of the base plate is the bearing line.

Declination:  The difference between True North (T) and Magnetic North (M)—Use 15 Degrees. In this part of California . . .

  • True = Magnetic – 15
  • Magnetic = True + 15