Southern Cross

d. Moon Navigator. Like the sun, the moon rises in the east and sets in the west. Use the same method of the shadow stick as you did during the day.

5. IMPROVISED COMPASSES. There are three improvised techniques to construct a compass.

a. Synthetic technique. The required items are a piece of synthetic material, (i.e., parachute cloth), and a small piece of iron or steel that is long, thin, and light. Aluminum or yellow metals won't work (only things that rust will do). A pin or needle is perfect, but a straightened paper clip, piece of steel baling wire, or barbed wire could also work.

(1) Stroke the needle repeatedly in one direction against the synthetic material. Ensure that you lift the material a few inches up into the air at the end of each stroke, returning to the beginning of the needle before descending for another stroke in the same direction. Do this approximately 30 strokes. This will magnetize the needle.

(2) Float the metal on still water using balled up paper, wood chip, or leaf.

Gather some water in a non-magnetic container or a scooped out recess in the ground, such as a puddle. Do not use a "tin can" which is made of steel. (An aluminum can would be fine.) Place the float on the water, then the metal on it. It will slowly turn to orient itself.

b. Magnet technique. You will achieve the same results by using a magnet. Follow the same steps as you did with the synthetic material. The magnets you are most likely to have available to you are those in a speaker or headphones of a radio.

c. Magnetization through a battery. A power source of 2 volts or more from a battery can be used with a short length of insulated wire to magnetize metal. Coil the wire around a needle. If the wire is non-insulated, wrap the needle with paper or cardboard. Attach the ends to the battery terminals for 5 minutes.

d. Associated problems with improvised compasses. The following are common problems with all improvised compasses.

(1) Soft steel tends to lose its magnetism fairly quickly, so you will have to demagnetize your needle occasionally, though you should not have to do this more than two or three times a day.

(2) Test your compass by disturbing it after it settles. Do this several times. If it returns to the same alignment, you're OK. It will be lined up north and south, though you will have to determine by other means which end is north. Use the sun, stars, or any other natural signs in the area.

(3) Remember, this will give magnetic north. In extreme northern lattitudes, the declination angle can be extreme.

6. NATURAL NAVIGATION.

a. Find out where the prevailing winds originate.

b. Sun's path in Northern Hemisphere is SE-SW

1. Bend in trees because of prevailing winds.

2. Sapling Coloration: whiter on one side, darker green on the other. The sunny side (south side) will cause the tree to turn whitish which is a natural sunscreen. White will be on the SW to SE side of the tree. Pick one that is in the open, exposed to the elements all day.

3. Hottest side of a slope will enhance growth: thicker vegetation the SW side.

4. Snow melt on one prominent side of the tree: melt/freeze will indicate the south side.

5. Bleach Rock: the sun's rays has a bleaching effect, lighter side will be to the south. Obviously white rocks are just white rocks.

c. Look for more than one sign to confirm your direction.

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