Methods of Finding North

 

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 accurate direction if you know the terrain of the territory or country. 

Before setting off on any expedition you must learn all you can about the area you are going to be in, 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.

As we are located in the UK the methods below are relevant to the northern hemisphere.

USING THE SUN & THE SHADOWS

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 as there is 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. (Shadows will move clockwise).

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:

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.

2. Wait 10 to 15 minutes until the shadow tip moves a few centimetres. Mark the shadow tip's new position in the same way as the first.

3. Draw a straight line through the two marks to obtain an approximate east-west line.

4. Stand with the first mark (west) to your left and the second mark to your right--you are now facing north.

An alternative method is more accurate but requires more time.

1. Set up your shadow stick and mark the first shadow in the morning.

2. Use a piece of string to draw a clean arc through this mark and around the stick.

3. 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.

4. Draw a line through the two marks to get an accurate east-west line (see Figure).

The Watch Method

You can also determine direction using a common or analogue watch--one that has hands. The direction will be accurate if you are using Greenwich Mean Time (Winter), instead of daylight savings or British Summer time. 

Remember, the further you are from the equator, the more accurate this method will be. If you only have a digital watch you will need to imagine or draw where the hour hand would be.

1. Hold the watch flat and point the hour hand at the sun.

2. Bisect the angle between the hour hand and the 12 o'clock mark to get the north-south line (See Figure). 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 to British Summer Time, use the midway point between the hour hand and 1 o'clock to determine the north-south line.

USING THE STARS

The main constellations to learn are the Ursa Major, (also known as the Big Dipper or the Plough), and Cassiopeia.

Neither of these constellations ever sets. They are always visible on a clear night. Use them to locate the North Star, also known as the polestar or Polaris.

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 counter clockwise around the North Star. The Big Dipper is a seven star constellation in the shape of a spoon (or as our cousins on the other side of the Atlantic say, a dipper). The two stars forming the outer lip of this spoon 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 almost straight out from Cassiopeia's centre star.

After locating the North Star, locate the North Pole or true north by drawing an imaginary line directly to the earth.

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 non-metallic 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 non-metallic string, or floated on a small piece of wood in water, it will align itself with a north-south line.  

You can construct a more elaborate improvised compass using:

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 centre of your container; this portion should be flush on the bottom and not interfere with the lid. Attach the centre 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 snow pack is shallower.

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