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Basic Compass Techniques

compass parts

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 2

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 3

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.

These compass techniques were taken from BACKPACKER magazine April 1999 issue.

Using the Sun and Shadows

Shadow-tip method

  1. Find a straight stick about 3 feet (1 meter) long and a fairly level, brush free spot (so that the stick will cast a definite shadow.
  2. Push the stick in the ground so it stands upright. It doesn’t need to be perfectly vertical to the ground.
  3. Mark the tip of the shadow cast by the stick.
  4. Wait until the shadow moves 1.5 to 2 inches (approximately 10-15 minutes).
  5. Mark the tip of the second shadow.
  6. Draw a line from the first mark through and about a foot beyond the second mark.
  7. Stand with your left foot on the first mark and your right foot on the end of the line you drew.

If you are in the northern temperate zone, you will be facing in a northerly
direction and you will know the other directions by recalling their relation
to north.

If you are in the southern temperate zone, you will be facing in a southerly
direction.

Watch method

You can also determine the direction using a watch. The steps you take
will depend on whether you are in the northern temperate zone or in the
southern temperate zone (and whether you have a conventional or digital
watch). The northern temperate zone is located between 23.4o north and
66.6o north. The southern temperate zone is located between 23.4o south
and 66.6o south.

Northern Temperate Zone (conventional watch)

  1. Place a small stick in the ground so that it casts a definite shadow.
  2. Place your watch on the ground sot that the hour hand points toward
    and along the shadow of the stick.
  3. Find the point on the watch midway between the hour hand and 12 o’clock
    and draw an imaginary line from that point through and beyond the center
    of the watch. This imaginary line is a north-south line.

NOTE: If your watch is set on daylight savings time, then use the midway
point between the hour hand and 1 o’clock to draw your imaginary line.

Southern Temperate Zone (conventional watch)

  1. Place a small stick in the ground so that it casts a definite shadow.
  2. Place your watch on the ground sot that 12 o’clock points toward and
    along the shadow of the stick.
  3. Find the point on the watch midway between the hour hand and 12 o’clock
    and draw an imaginary line from that point through and beyond the
    center of the watch. This imaginary line is a north-south line.

If you carry a digital watch, simply draw a conventional watch face on the
ground with the hands indicating the proper time (as shown on your digital
watch) – following the same steps as listed above.

The Sun and Shadow techniques were taken from the US Army Survival Manual
FM21-76 (Dorset Press, 1992).