.................................
Survival
Skills If You Lost Your Way
FIELD-EXPEDIENT DIRECTION FINDING
In a survival situation,
you will be extremely fortunate if you happen to have a map and compass.
If you do have these two
pieces of equipment, you will most likely be able to move toward help. If you
are not proficient in using a map and compass, you must take the steps to gain
this skill.
There are several methods by which you can
determine direction by using the sun and the stars. These methods, however,
will give you only a general direction.
You can come up with a
more nearly true direction if you know the terrain of the territory or country.
You must learn all you can
about the terrain of the country or territory to which you or your unit may be
sent, especially any prominent features or landmarks.
This knowledge of the
terrain together with using the methods explained below will let you come
up with fairly true directions to help you navigate.
.
.
The
earth's relationship to the sun can help you to determine direction on earth.
The sun always rises in the east and sets in the west, but not exactly due east
or due west.
There is also some seasonal
variation. In the northern hemisphere, the sun will be due south when at its
highest point in the sky, or when an object casts no appreciable shadow.
In the southern hemisphere,
this same noonday sun will mark due north.
In the northern hemisphere,
shadows will move clockwise. Shadows will move counterclockwise in the southern
hemisphere.
With practice, you can use
shadows to determine both direction and time of day. The shadow methods used
for direction finding are the shadow-tip and watch methods.
Shadow-Tip Methods
In the
first shadow-tip method, find a straight stick 1 meter long, and a level spot
free of brush on which the stick will cast a definite shadow. This method is
simple and accurate and consists of four steps:
· Step 1. Place the stick or branch into the ground at a
level spot where it will cast a distinctive shadow. Mark the shadow's tip with
a stone, twig, or other means. This first shadow mark is always west--everywhere on
earth.
· Step 2. Wait 10 to 15 minutes until the shadow tip moves
a few centimeters. Mark the shadow tip's new position in the same way as the
first.
· Step 3. Draw a straight line through the two marks to
obtain an approximate east-west line.
· Step 4. Stand with the first mark (west) to your left
and the second mark to your right--you are now facing north. This fact is
true everywhere on earth.
An
alternate method is more accurate but requires more time. Set up your shadow
stick and mark the first shadow in the morning.
Use
a piece of string to draw a clean arc through this mark and around the stick.
At midday, the shadow will shrink and disappear.
In
the afternoon, it will lengthen again and at the point where it touches the
arc, make a second mark. Draw a line through the two marks to get an accurate
east-west line (see Figure 18-1).
The Watch Method
You can
also determine direction using a common or analog watch--one that has hands.
The direction will be accurate if you are using true local time, without any
changes for daylight savings time.
Remember,
the further you are from the equator, the more accurate this method will be. If
you only have a digital watch, you can overcome this obstacle.
Quickly
draw a watch on a circle of paper with the correct time on it and use it to
determine your direction at that time.
In the
northern hemisphere, hold the watch horizontal and point the hour hand at the
sun. Bisect the angle between the hour hand and the 12 o'clock mark to get the
north-south line (Figure 18-2).
If
there is any doubt as to which end of the line is north, remember that the sun
rises in the east, sets in the west, and is due south at noon. The sun is in
the east before noon and in the west after noon.
Note: If your watch is set on daylight
savings time, use the midway point between the hour hand and 1 o'clock to
determine the north-south line.
In
the southern hemisphere, point the watch's 12 o'clock mark toward the sun and a
midpoint halfway between 12 and the hour hand will give you the north-south
line (Figure 18-2).
USING THE MOON
Because the moon has no light of its own,
we can only see it when it reflects the sun's light.
As
it orbits the earth on its 28-day circuit, the shape of the reflected light
varies according to its position. We say there is a new moon or no moon when it
is on the opposite side of the earth from the sun.
Then,
as it moves away from the earth's shadow, it begins to reflect light from its
right side and waxes to become a full moon before waning, or losing shape, to
appear as a sliver on the left side. You can use this information to identify
direction.
If the
moon rises before the sun has set, the illuminated side will be the west. If
the moon rises after midnight, the illuminated side will be the east.
This
obvious discovery provides us with a rough east-west reference during the
night.
USING THE STARS
Your location in the Northern or Southern
Hemisphere determines which constellation you use to determine your north or
south direction.
The Northern Sky
The main
constellations to learn are the Ursa Major, also known as the Big Dipper or the
Plow, and Cassiopeia (Figure 18-3).
Neither
of these constellations ever sets. They are always visible on a clear night.
Use them to locate Polaris, also known as the polestar or the North Star.
The
North Star forms part of the Little Dipper handle and can be confused with the
Big Dipper.
Prevent
confusion by using both the Big Dipper and Cassiopeia together.
The
Big Dipper and Cassiopeia are always directly opposite each. other and rotate
counterclockwise around Polaris, with Polaris in the center.
The
Big Dipper is a seven star constellation in the shape of a dipper. The two
stars forming the outer lip of this dipper are the "pointer stars"
because they point to the North Star.
Mentally
draw a line from the outer bottom star to the outer top star of the Big
Dipper's bucket. Extend this line about five times the distance between the
pointer stars. You will find the North Star along this line.
Cassiopeia
has five stars that form a shape like a "W" on its side. The North
Star is straight out from Cassiopeia's center star.
After
locating the North Star, locate the North Pole or true north by drawing an
imaginary line directly to the earth.
The Southern Sky
Because
there is no star bright enough to be easily recognized near the south celestial
pole, a constellation known as the Southern Cross is used as a signpost to the
South (Figure 18-4).
The
Southern Cross or Crux has five stars. Its four brightest stars form a cross
that tilts to one side. The two stars that make up the cross's long axis are
the pointer stars.
To
determine south, imagine a distance five times the distance between These stars
and the point where this imaginary line ends is in the general direction of
south.
Look
down to the horizon from this imaginary point and select a landmark to steer
by. In a static survival situation, you can fix this location in daylight if
you drive stakes in the ground at night to point the way.
MAKING IMPROVISED COMPASSES
You can construct improvised compasses
using a piece of ferrous metal that can be needle shaped or a flat double-edged
razor blade and a piece of nonmetallic string or long hair from which to
suspend it.
You
can magnetize or polarize the metal by slowly stroking it in one direction on a
piece of silk or carefully through your hair using deliberate strokes.
You
can also polarize metal by stroking it repeatedly at one end with a magnet.
Always rub in one direction only.
If
you have a battery and some electric wire, you can polarize the metal
electrically. The wire should be insulated. If not insulated, wrap the metal
object in a single, thin strip of paper to prevent contact.
The
battery must be a minimum of 2 volts. Form a coil with the electric wire and
touch its ends to the battery's terminals. Repeatedly insert one end of the
metal object in and out of the coil.
The
needle will become an electromagnet. When suspended from a piece of nonmetallic
string, or floated on a small piece of wood in water, it wil l align itself
with a north-south line.
You can
construct a more elaborate improvised compass using a sewing needle or thin
metallic object, a nonmetallic container (for example, a plastic dip
container), its lid with the center cut out and waterproofed, and the silver
tip from a pen.
To
construct this compass, take an ordinary sewing needle and break in half. One
half will form your direction pointer and the other will act as the pivot
point.
Push
the portion used as the pivot point through the bottom center of your
container; this portion should be flushed on the bottom and not interfere with
the lid.
Attach
the center of the other portion (the pointer) of the needle on the pen's silver
tip using glue, tree sap, or melted plastic. Magnetize one end of the pointer
and rest it on the pivot point.
OTHER MEANS OF DETERMINING DIRECTION
The old saying about using moss on a tree
to indicate north is not accurate because moss grows completely around some
trees.
Actually,
growth is more lush on the side of the tree facing the south in the Northern
Hemisphere and vice versa in the Southern Hemisphere.
If
there are several felled trees around for comparison, look at the stumps. Growth
is more vigorous on the side toward the equator and the tree growth rings will
be more widely spaced.
On
the other hand, the tree growth rings will be closer together on the side
toward the poles.
Wind
direction may be helpful in some instances where there are prevailing
directions and you know what they are.
Recognizing
the differences between vegetation and moisture patterns on north- and
south-facing slopes can aid in determining direction.
In
the northern hemisphere, north-facing slopes receive less sun than south-facing
slopes and are therefore cooler and damper.
In
the summer, north-facing slopes retain patches of snow. In the winter, the
trees and open areas on south-facing slopes are the first to lose their snow,
and ground snowpack is shallower.
http://www.wilderness-survival.net/chp18.php
Knowing You
You might also like:
CLICK HERE . . .
...............
CLICK HERE . . .
.....................
(All I once held
dear)
CLICK HERE . . . to view complete
playlist . . .
No comments:
Post a Comment