Among the important items every hiker or trekker needs is a functioning compass for safety and security. The best type compass for most people is an analog compass, which is correctly calibrated and perfectly balanced. An expensive compass does not necessarily mean good quality. Analog compasses are in an encased round case. Sometimes the glass has beveled edges and under the glass is the compass needle.
I wish I bought a compass and not this book.
Some compasses have a clear liquid, which balances the needle and prevents uncontrolled bouncing. The liquid serves as a cushion or buffer for the compass needle preventing it from damage if dropped. Not all compasses are analog but most hikers and trekkers choose them because they are sturdier than digital compasses and other more sophisticated instruments.
Everyone who wants to use a compass must first know the four main directions, North, South, East and West and have some of idea or mental picture of these directions. The most important direction is north. The majority of hand-held analog compasses include a red and black or black and white arrow called a compass needle. The red end is the most important because it always points toward the North Pole.
A compass has a turntable called the compass housing on which it rotates when exposed to a magnetic field. Near the edge of the housing is a scale with numbers from 0-360 on most compasses. These numbers represent the degrees, which are the azimuth or the bearing. Around the face of the compass, you see the letters, N, S, E and W, which of course represent the cardinal points of North, South, East and West.
Not those Cardinals!
The halfway point between north and each of the other cardinal points are intercardinal points. The points denote the Northeast, Southeast, Northwest and Southwest points. The points between each cardinal point and each intercardinal point are the secondary intercardinal points, which designate the directions North-Northeast; East Northeast; East Southeast; South Southeast; South Southwest; West Southwest; West Northwest and North Northwest. In total, there are 16 distinct direction points along the circular path of a compass.
A second type of analog compass is one with a liquid filled tube containing an air bubble. The liquid with the bubble is similar to a level used by architects, builders, decorators and others. When you hold the compass level, the air bubble will show you the compass cardinal, intercardinal points: North, South, East, West, Northeast, Northwest, Southeast and Southwest and the secondary intercardinal points. Anyone who knows how to read a carpenter’s level can easily read a compass having a liquid filled tube with a bubble serving as the balancing point.
Between each of the cardinal, intercardinal and secondary intercardinal points there are numbers, which designate a certain number of degrees ranging from 0 and 360 as you move in a clockwise direction around the compass. The bearing between north and east is 90 degrees; moving from north to south the bearing is 180 degrees; from north to west is 270 degrees and moving from there back to north is 360 degrees, which happens to be the circumference of a circle.
If you’re clever, you can go anywhere with this
Why are there 360 degrees in a circle? Well according to scientific lore, the early Babylonians discovered it takes 360 days and nights for the stars to move around the sky and return to their original place in the universe. Using this information, they developed a calendar consisting of 360 days and nights. Then because they knew stars moved in a circular fashion about the universe and since a circle is circular, they decided to use 360 degrees as the distance around a circle. Today we learn early in grade school math classes, the circumference of a circle is 360 degrees.
The Babylonians still have credit for this accomplishment. However, they were off a little on the number of days and nights in a year, because scientists after them proved there are 365 days in a year with the exception of leap year, which has only 364. There is no February 29 in leap year, which rolls around every four years.
So it should be 365 degrees then!
Oh, by the way do not forget to keep your compass away from your pocketknife, flashlight, keychain and similar objects containing metal. Remember the compass has an internal magnetic field. Metal objects and magnetic fields are enemies. Once the magnetic field of a compass suffers damage, the compass is of no value.
In working with a compass, think in terms of north, south, east and west rather than left, right, up and down. A compass does not point true north, south, east or west, but points to the magnetic north, south, east or west. The magnetic field draws the needle in each direction causing the compass needle to move. There is a slight variance in degrees between true north and magnetic north.
Some compasses today are digital and like so many pieces of equipment some people believe digital is better, but in some cases it is not better than analog. A digital compass is not as dependable as an analog compass. If you drop a digital compass, damage to the internal circuit board is often the result. A broken circuit board is as serious as a lost compass. You cannot repair it as you can an analog compass. In addition, if a digital compass gets wet from inclement weather or falls into a stream you are stuck with a non-functioning compass.
Which is better? Digital or normal?
The compass needle, points to the direction you are facing.
1. Test your compass holding it in the palm of your hand. Rotate your body watching the needle of the compass. When it sits perfectly still on the line designated as North, you are facing north at 360 degrees.
2. Always hold the compass perfectly still or the needle will bounce around between the lines. If the needle is not giving you exact readings then one of two things can be wrong.
a) You are not facing in a direct line with the sun or
b) Your compass is improperly calibrated or out of balance
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