Using a Compass Without a Map
A Very Basic Compass Like This One Will Work if You Know How to Use It
A Compass Is For Getting Your Bearings
A compass is a wonderful tool for finding your way around compass points that confuse so many people. How to use and read a compass, (if you are traveling any distance off the beaten path without a GPS device), is an essential survival skill.
Why? No handy outlets to plug in battery-chargers exist out in nature, so your GPS unit won't be of much use. Compasses range from simple to complicated, depending on what you are planning to do.
Lost and Found Again
Sometimes, a very basic single direction is all you need, and a ‘general’ trek that way will be sufficient. This was the case one time many, many years ago when I was hiking with a couple of other people, and all of a sudden, we noticed that the trail we’d been following had petered out, and we were in the middle of the woods!
Oh, dear! What to do?? Well, we did have a compass with us, and arbitrarily chose to travel north, and kept on that path. Since we were not out in a backcountry wilderness, but in Muir Woods National Monument in Northern California, a park surrounded by urban areas, we knew that at some point we’d come out of the woods into something we either recognized, or could find help to get back to our car.
Let me back up. We did not begin in Muir Woods. We started out hiking the Dipsea Trail from Mount Tamalpais, heading for its end at Stinson Beach. Either we made a wrong turn, or the trail markers were unclear or obscured. Whatever the cause, we ended up off the trail, and that’s how we ended up "lost" in the woods. It took over 3 hours of scrambling up and down miniature mountain ranges—gullies and hills--and some occasional scrambling up a tree to see if we could see any further and get our bearings: no such luck! However, by following north persistently, we did eventually come out onto one of the trails within Muir Woods.
Muir Woods Was Not Our Original Destination!
Why People Get Lost Without a Compass
Without that compass, however, our chances for coming out in the 3 hours would have been doubtful. We probably would have ended up walking in large circles, daylight would have faded, and we’d have been stuck there all night, become the subject of a newscast and objects of a search party the following day. This is a main cause of people getting lost. Part of the reason you end up going in circles is physical. Whichever ‘handed’ you are, your dominant-side leg probably takes a slightly longer stride. After some distance, the effect of this is to bring you back around toward your starting point.
Disorientation is the other factor. In the middle of the woods, after a while, especially if you become fearful, and therefore stop thinking logically and calmly, every branch and twig and leaf and fallen log starts to look the same…or do they? Maybe they always look different. Maybe they are different. As the day wears on and the light fades, this effect is increased. This confusion can lead to panic. Panic leads to poor decision-making, which in turn can lead to disaster.
With a compass in hand, however, you are walking with purpose: it is easy to stay on track and not go in circles. If you are surrounded by an urban area, as we were, you will eventually come out of the woods. If, however, you plan on going out into the wilderness, you had jolly well better have very advanced compass and map skills.
Introduction to the Compass
Here is a photo of a basic compass, of a type which can also be used for some of the more advanced uses. Any compass will work, even a cheapie ‘toy’ variety. The difference is that the ‘cheapies’ are very simple, and the needle jiggles around a great deal, making it hard to settle down to get an accurate reading. The type shown in the first two photos is a liquid-filled type, and is much more stable.
Parts of a Compass
Let’s begin with naming the parts of the compass—this will make it all much easier to understand as we go along. If you refer to the photo above, you can see these parts illustrated.
- First, there is the base plate. This is the support for the compass, and also part of the tool for more advanced operations such as orienting oneself to a map.
- Printed on the base plate and pointing off the edge is the direction-of-travel arrow.
- Next, the most important part, the compass housing which contains the magnetic needle.
- Around the outer edge of the compass housing is the dial, which rotates to align oneself to the desired direction.
- Inside, printed on the bottom of the housing, is the orienting arrow.
How a Compass Works
The magic is in the magnetic end of the compass needle. By tradition, it is always painted red. This red end is magnetized, and will always point to magnetic north, with one caveat: it can be fooled by nearby large metal (iron or steel) objects, such as cars or filing cabinets. But at a reasonable distance away from these things, it will swing true again.
Avoiding Direction-of-Travel Errors
A common mistake many beginners make is to think that the magnetic needle must be lined up with the “north” indicator on the dial and the direction of travel arrow and the orienting arrow. This is not true, unless you actually want to travel to the north.
What needs to happen instead, is to decide your direction of travel, and rotate the dial without turning the base plate in your hand, so that the compass point you've chosen lines up with the direction of travel arrow on the base plate.
Now, again without turning the compass in your hand, rotate yourself until the orienting arrow lines up under the red end of the magnetic needle. You are now facing your desired direction. Remember--the direction of travel arrow must always point away from you to the front. It should never point at you--unless you are planning to walk backwards--not recommended. ;-)
Direction of Travel Arrow Properly Aligned
How to Use the Direction-of-Travel Arrow
At this point, that red end of the needle will be pointing somewhere away from where you want to go, either right at you (indicating behind you) or off to one side or the other. This can be ignored. Simply keep holding the compass steady and in the same relative position to yourself, and you will be heading the way you wish to go.
As long as you hold the compass pointing true to your forward direction, and maintain the orienting arrow under the red end of the magnetic needle, you will be on course.
Here is a fun, short exercise to illustrate that point. It is called triangulation. Triangulation is very useful in many ways, one of which being how various seismograph stations determine the epicenter of any earthquake.
This little exercise is triangulation at its most basic, reduced to an educational game you can play with the kids. Little do they realize they will be tricked into doing (gasp! math!) in their heads in order to play. (Don’t spoil the fun by telling them it’s educational!)
A Basic Compass Walk
Ready? Ok. Compass in hand. Pick any bearing at random between 0 and 120 degrees. Set your chosen heading on the direction of travel arrow, as explained above. Drop some kind of marker between your feet. Now, pace off a pre-determined number of steps (let’s say 40 for purposes of illustration), and walk your chosen bearing for that number of steps. Stop.
Add 120 to the number of your original bearing. Set the new heading and turn to face that direction. Walk the exact same number of paces as before. Stop.
Again add 120 to the previous number (your second bearing). Set this new bearing, and walk again the same exact number of steps. Stop. Look down. If you did it right, you should find yourself within at least a shoe’s length of your starting marker.
Setting the First Bearing
1st Bearing Destination = 2nd Leg Bearing Set
Use of a Compass as a Sporting Activity
Not only is this elementary triangulation, it is the basis for an entire sport called orienteering. That gets into much more complex bearing determinations, necessary detours around obstacles, and advanced calculations to allow for the difference between true north and magnetic north. Yes, there is one: it’s called declination. That’s a whole other topic, far beyond the scope of this article on basic compass use.
Yet another sporting use is the relatively new geo-caching, in which small containers are hidden in various places, and compass bearings and latitude/longitude references are provided for finding the container, or 'cache' (pronounced the same as 'cash' in referring to money). Inside the container will be, depending on its size, a piece of paper (log) to sign to show you were there, or a trinket to take, with a new trinket expected to be left in its place.
Now get off the couch, grab a kid, and go outside and play!
A Useful Trick
In closing, here is a useful little trick you can use to tell time if you don't have a wristwatch or any other time-keeping device with you.
Once you know where north is, you can use your hands as a portable sundial. Obviously, this only works on sunny days, not rainy or overcast days.
Stand facing north, hold your left hand, palm down, fingers curled under, and your forearm held parallel to your torso.
Using your index or 'pointer' finger of your right hand, place the point of your finger against the center of the back of your left hand. Keep your index finger straight, and the others curled under out of the way.
You want a good 90-degree angle between your finger and the back of your hand, and this is most easily done by raising your upper arm from the shoulder so your elbow is cocked upwards a bit, and your wrist bent down to make your finger touch the other hand.
Now, imagine the back of your left hand as a clock face, and mentally place the numerals in their normal positions. Look where the shadow of your finger falls. Now you know the time.
This gives an approximate hour; it will not account for minute-by-minute intervals, nor will it tell 'daylight saving time'--you need to make that adjustment yourself.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2010 Liz Elias