Simple Compass

I assume the Boy Scouts still teach you how to read a compass, but since it’s been nearly 50 years since I was a Boy Scout, I’ve forgotten what I learned so let’s start a new and learn the basics of how to read a compass.

A compass is a complicated piece of survival equipment which can simply help you find which direction you’re heading, to specific latitude and longitude settings to pin point your position from anywhere on earth. But let’s begin at the beginning as they say.

When discussing compass directions there is no turn right or left direction of travel, right or left depends on which way you are facing. Instead we use what are known as Cardinal Points, which are North, South, East and West. These points remain constant no matter which way you’re facing. North will always be North. You may have to turn left, right or about face to reach North, but it’s constant and unchanging.

To get to more specific points we use what are known as Inter-Cardinal Points, Northeast, Southeast, Northwest and Southwest. These points are divided again into what’s known as Secondary Inter-Cardinal Points, which is located between each Cardinal and Inter-Cardinal point. These points are North-Northeast, East-Northeast, South-Southeast, East-Southeast. The compass can be broken down into tinier points, but it gets ridiculous. However, there will be instances where a more exact point is required and that will be broken down by degrees. (A compass is split into 360 degrees)


Test Your Compass

You just bought a new compass and of course assume it works properly. Do you really want to trust that some worker in China did his job correctly with a piece of equipment that could save your life? I think not. Let’s test it for accuracy. All compasses have a needle and nearly everyone of them have the North end of the needle colored Red. Make a mental note if yours is different.

Be sure to hold the compass level or the needle may rub against the glass (plastic) front and not read correctly.

May sound dumb, but … be sure you’re reading the correct end of the needle.

Simple test. If you are North of the equator, stand facing the sun at lunchtime (noon) and holding the compass in your hand in front of you, whichever end of the needle facing the sun will indicate South… the end (red most likely) will point towards you and indicates North.

Now, if you are South of the equator, down under as it’s known, the reverse will happen. The red apart will face the sun, indicating North, South is pointed towards you.

Basic Layout of a Compass

Designs and technical difficulty will vary between compasses, but they will all include a magnetized needle which will orientate itself to the magnetic fields of the earth.

The base-plate is the clear plastic (used to also be glass), plate on which the compass is embedded.

The Direction-of-travel arrow points away from the compass

The compass Housing is the clear plastic circle that houses the magnetized needle

The Degree Dial surrounds the entire compass that can be rotated to show 360 degrees

The magnetic needle is the one that spins within the compass housing.

The Orienting arrow is the non-magnetic arrow within the compass housing

The Orienting Lines run parallel to the orienting arrow

North vs True North

As if this isn’t difficult enough you are now telling me there are 2 Norths. Yep. Afraid so. But not to panic, for your purpose this is for general knowledge sake, because it could effect you in certain situations.

True North or Map North refers to the point where all longitudinal lines meet at the North pole. Remember, All maps are laid out the same. True North is always the very top of the map. However, the earth doesn’t much care about our maps and there will be slight variations in the earth’s magnetic field which is where your compass needle will point. Therefore, your compass will be pointing to Magnetic North … not True North.

So what’s the big deal? Without getting too technical, True North and Magnetic North, depending on where you’re at on earth, could vary by as much as 20 degrees. For our general purpose that poses no real problem, it probably won’t matter if you walk 1 mile and miss your destination by 100 feet. But if you’re walking 10 miles through the wilderness, without compensating for the declination, you could miss your destination by a rather far margin. Important if pinpoint accuracy is required.

Focal Points

In order to stay on course and follow the direction of travel arrow, not as easy as it sounds depending on the terrain you’re trans-versing, use focal points. Holding your compass at eye level, look down the travel arrow and locate a distant object, like a certain tree or other distinct landmark, then walk to that spot. Repeat the procedure. Don’t use a landmark which is too large, like a mountain, or one too far away as you could lose sight of it while walking.

Let’s say you and your companion are traveling in a desert type environment with no large visible landmarks available. Stand at one spot, do not move, and have your partner walk away in the direction you need to go as you look down the travel arrow. Correct his path as he goes by yelling or hand signals. Once he’s nearly out of sight have him stop still. Sounds stupid, but be sure he doesn’t wander around the area looking for a soft spot to sit. He needs to sit down exactly where he is as to not distort your navigation. You catch up to him and repeat the process.

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