MAP & COMPASS TOGETHER


THE TRUE NORTH METHOD

The other method commonly used, which does the same job as the Magnetic North Method, is the True North Method. A small strip of tape, on the face of Needle Compass Rose, at the proper Declination, can turn your compass into a True North Compass.

Right now, get up, and place a 1/8 inch strip of tape from the center of your compass, to the correct degrees of declination in your area. (Riverside, Calif, is 15.25 Deg.) This will be necessary in order to follow along with this instruction.

From this time forward, there are only 2 rules:

When taking Field Bearings... Put the "Compass Needle" to "Tape," - Always!
When taking Compass Bearings... Put the "Housing Meridian Lines" to the "Longitudinal Meridian lines on the Map," - Always!

That's it... That's all there is to it...

Read them again...

Now the "Compass Rose," "Base Plate," and the "Map," any map, all speak the same language of True North, while the "needle" still points to MN. There is no need to draw lines on any map, and the need to "Box the needle" is eliminated. All bearings are then given as "True North Bearings," and you can forget the declination, because the compass has included it in its measurement. Be sure to mark it TN when you write it down.

HOW TO WALK A BEARING

Try this outside. Pick the Compass up and place in the palm of your hand. Turn the Azimuth Ring dial to some random number on the Compass Rose. Now holding the Compass chest high in front of you, turn your body and Compass together as a unit, until the Needle points to the tape. Now look out beyond the compass, straight ahead. The further out you can look beyond your destination the better. Choose some "landmark" or "Steering Spot" which is in line with the direction you wish to travel, as pointed to by the "Direction of Travel Arrow" on the Compass Base Plate. You would then put the Compass away, and walk to that landmark, or spot, without looking at the Compass again. When you get there, then use the Compass to locate the next bearing, and locate the next landmark, then put the compass away again. It is just that easy... (Note do not walk while staring at the Compass Needle, you might stumble over something, or get bitten by a snake, or eaten by a bear! Watch where you are going in the wilderness. Use "Steering Marks"!)

Here is another exercise to try outside to show you just how trust worthy a compass really is. Get all your boys out to do this one. Place the end of a stick into the ground directly at your feet. Set your COMPASS ROSE, or Azimuth Ring, to some arbitrary direction between 0 and 120 Degs. (Let's say 60 Degs.) Now turn your body and Compass as a unit till the Compass Needle points to the tape (Declination). Face this direction and walk this bearing for a nice evenly spaced 20 Paces... (Double steps, about 100 feet). Then stop.

OK. Now look at your Compass again. Add 120 Degs to the first arbitrary direction you used, (Like 60 Degs + 120 Degs = 180 Degs.) and set this new Bearing on your Compass Rose. Again, turn your body and Compass as a unit till the Compass Needle points to the tape (Declination, Not to North). Walk another 20 Paces... Stop.

Now one last time. Look at your Compass again. Add yet another 120 Degs to your last setting (180 Degs + 120 Degs = 300 Degs), and reset your Compass Rose. Turn your body and Compass till the needle points to Declination again, then walk 20 Paces again... Stop.

If your pace was smooth, and evenly distanced, at your feet should be that stick... This test is very good practice. It can instill a lot of faith in the compass...

Try 4 turns of 90 Degs each, or 5 turns of 72 degrees each.

BACK BEARING

A Back Bearing, means to reverse direction along the way you just came, or back tracking. Simply add or subtract 180 degrees from your present bearing, and turn the DIRECTION OF TRAVEL ARROW to this new heading, turn around and walk back the way you came.

Or another way with an Orienteering Compass, you can simply hold the whole compass and Base Plate backward in your hand, without touching the Needle Housing, and follow the Base Plate back the way you came.

HOW TO ORIENT A MAP

First of all, find True North with the Compass, and align the Needle to the tape (Declination, Not North). Open the Map and place it on a rock or the flat ground. Turn the Map so that the Compass's Meridian Orienting Lines and the Map's True North are aligned. Now the map matches the landscape exactly.

HOW TO GET A MAP BEARING FROM THE MAP TO THE LANDSCAPE

Simply place the Compass on the open Map. Put the rear-corner edge of the Base Plate directly on your present location. Move the straight edge of the Base Plate, into the direction you wish to travel. Now turn the Compass Rose till the Needle Housing, Meridian Orienting Lines match the Map's North/South lines. That's all there is to it...

Now pick up the Compass and hold it properly, and turn it and your body as a unit, till the needle points to the Declination Tape (Not North). The "Direction of Travel Arrow" on the Base Plate now points the way to go. Sight on a distant object beyond your target, and fix it in your mind. Put away the Compass and walk towards your destination along your landmark bearing line.

As you walk you may find your self side stepping obstacles in your way. Any time you step to the left or to the right of your Bearing, say to travel around boulders, or clumps of foliage, to reach your destination landmark, you practice CIRCUMNAVIGATION. Your distant visual landmark brings you back to your correct bearing. This is why "Steering Marks" are SO important.

Note, when using an Orienteering Compass, to get a MAP BEARING to a FIELD BEARING, the -Map does not have to be oriented to North!

HOW TO PLOT A FIELD BEARING ONTO A MAP

Hold your Compass properly, and turn your body and Compass as a unit, to the direction you have visually decided to travel in. Now, turn the Compass Rose till the Needle points to the Declination Tape (Not North). This is called "taking a bearing." Then place the Compass on an oriented (or un- oriented) map. Turn the whole device around until the MERIDIAN ORIENTING LINES, on the Needle Housing, line up with True North lines on the map (North to North, totally ignore the magnetic needle at this point). Align the rear-corner of the BASE PLATE to your present location, and draw a line in the direction you just measured from the field. This is the direction you are looking at to travel in. That's all there is to it...

BIANGULATION TO GET A "FIX" ON YOUR PRESENT LOCATION

Look around outside and find a prominent point in the landscape that can be identified on your Map. It can be a lake, mountain peak, road intersection, river fork, water falls, railroad track, anything that can be seen both on the Map, and on the landscape. Then hold your compass properly, and turn your body and the Compass, till the DIRECTION OF TRAVEL ARROW points to this prominent landmark feature. Now turn the COMPASS ROSE around until the Needle points to the Declination Tape (Not North), and get a reading or bearing in degrees. Ok, now place the compass on your oriented (or un-oriented) Map, and align the MERIDIAN ORIENTING LINES with the Map's True North. Draw a light line from the landmark back towards your position. Now take a 2nd reading from another prominent landmark about 90 Degs away from the 1st bearing. Again turn the COMPASS ROSE till the Needle again points to the Declination Tape (Not North). For a second time, place the compass on your Map and align the MERIDIAN ORIENTING LINES with the Map's True North, and draw a light line from the 2nd landmark back towards your position. Where the lines cross, is your exact location.

TRIANGULATION

This is the same as Biangulation, only that you take a 3rd reading from the landscape, and mark it also on your Map, as a form of checking your location. This works best if the readings are about 60 Degs from each other, and specifically not close together.

PACE Did it ever in your life, make you curious as to how come a statute mile is the uneven distance of 5,280 feet? Well, that's the distance that 1,000 paces would cover by a Roman foot solder 200 years B.C.. Our modern word "Mile" came from the Latin phrase, "Mille Passus," meaning "1,000 Paces." Today, this measurement is still very handy.

A Pace is the double-step distance between 2 right, or 2 left foot steps. It is about 5 feet in an adult, 4-1/2 feet in older children, and 2-1/2 feet in 10 year old's.

There is roughly 250 Adult PACES in 1/4 mile, and 500 PACES in a 1/2 mile. It is amazingly accurate. Everybody has a slightly different pace, so measure your own by marking off 100 feet and see how many paces it takes you to travel 100 feet. It should be from 18 to 21 paces.

Time and distance are directly related to each other in navigation.

time = distance / speed

The work done to walk straight up a steep hill 100 feet, can be greatly reduced by increasing the distance over which the work is to be done, as in switch-backing the hill. That way the same amount of work is done over a longer time.

work = time * horse power

Distance judged by time alone in the wilderness is unreliable due to the differing kinds if terrain. It takes about 20 minutes to walk a mile on open highway, 30 minutes to walk through open woods, 30 minutes for thick woods or foothills. So your best bet is to not use time, but use your PACE to measure distance in the wilderness instead.

During the planning stages of a trip, it is wise to plan each nights stay at each camp site. The time and distance can be an important bit of information. But they are tricky to figure if you don't have some idea of the time it takes to pace a mile.

The standard times to calculate travel time with a 35 pound backpack on is...

Ascending - 1 hour for every 2 horizontal miles, plus 1 hour for every 400 vertical feet of elevation gain.

Descending - 1 hour for every 2 horizontal miles, plus 1/2 hours for every 1,000 vertical feet of elevation lost.

This rate takes into account for a 10 minute break every hour.

The health of your group, the age of the individual, the type of landscape walking through, and expected weather, will all have an effect on the amount of time it's going to take. So the above times are only a rough idea.

CIRCUMNAVIGATION

While you are walking on a Bearing, you may come to an obstacle of some kind. It may be a lake, a clump of cactus, a swamp, a canyon, or a steep hill. Something you can't go through.

One method is turning 90 degs to the right or left of your present course, and taking a new bearing. Then while walking away, count every right foot step, till you clear the edge of the obstacle. Then turn and take another bearing at -90 degrees, to parallel your original heading. You do not have to count again yet. When you have gone far enough to clear the obstacle on this parallel direction, turn -90 degrees and take a new temporary Bearing. Walk, again counting every right foot step, until you have made the same number of paces that you first counted. When you have reached the pace count, turn +90 degrees, and resume on your original Bearing, to continue on your way.

Instead of taking the chance of forgetting your original bearing after you move the setting, another way of finding that 90 Degs to turn, is to take advantage of your Compass's base plate.

When you get to that obstacle, hold the Compass level, and sight along the back edge to a distant object (Steering Mark) at 90 degrees from your course, and count your steps toward it.

Then sight along the right edge of the Compass and walk for enough distance to clear the object.Then sight along the bottom edge again - recounting your steps back - and get back on your original heading.

DOG LEG (Advanced)

Another method involves taking only a +45 degree turn, for some number of paces. Then when the obstacle is cleared, turning -90 degrees, counting your paces again, where you turn +45 degrees to resume your original Main Bearing heading.

When you become really good at circumnavigation, you can set a Bearing. Then circumnavigate at +45 degrees in one direction of an obstacle for some number of paces. Then turn back -45 Degs to parallel your original main bearing for a while without counting. Then turn another -45 degrees, and recount your paces again, back towards your main bearing. Where you again turn +45 degrees to resume your original course. Cake Walk!

Actually, hiking can rarely ever be done in a straight line, Mankind has a tendency to walk in circles, and the land has so many irregularities. You improve the odds of reaching your destination if you...

1. Make careful, and accurate sightings on both the Destination Landmark, and all Intermediate Landmarks.

2. Follow the DIRECTION OF TRAVEL ARROW and NOT the Compass Needle when walking.

3. Recheck your bearings carefully to avoid an accumulation of small errors. If possible have more than 1 person take Bearings.

4. Use bearings only over short distances when possible.

5. Aim for a "line" on a Map rather than a "point" when possible. These are called "handrails." It is easier to hit a stream, a road, or a crest, than it is to hit a waterfall, or water tank.

6. Continuously plot your progress on a Map.

DEAD RECKONING, Aiming Off, or Offset Course. (Advanced)

This is a technique involving the knowledge of distance, in Paces, between you and some destination on a Map.

By calculating the correct number of paces, and then walking deliberately to miss the object on one side, you keep track of exactly where that destination is. It give you a bit of a "handrail."

For instance, if you knew you were say 300 paces west, outside of camp, and you headed directly east, into camp, in thick brush you may, or may not, hit the camp directly head on. You most likely will end up a little North or South of the camp site. But you notice that after arriving in the new location, you still don't see the camp. Now which direction do you go from here? Try all of them!!! You could very conceivably spend quite a bit of time looking around without finding anything.

By purposely walking 10 degrees off to one side (south of the camp), and walking east while counting the 300 paces. By turning 90 degrees north like clockwork, you will measurably be in the vicinity of the camp. This greatly increases your chances of hitting the camp.

CONTOURING

This is a method of walking around an obstacle, such as a hill, by keeping at the same elevation, and thus following the contour. This reduces the work expended by climbing and descending the hill, keeping you from exhausting yourself.

Want to know more? Want to learn how to forecast the weather with a compass? Want to stay found? Want to know how tall a tree really is? ...And more? Let me know.

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