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Using A Compass Troop |
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The first thing
you need to learn, are the directions. North, South, East
and West. Look at the figure and learn how they are. North is the most
important.
There are several kinds of compasses, one kind to attach to the map, one kind to
attach to your thumb. The thumb-compass is used mostly by orienteers who just
want to run fast, and this is the kind of compass I normally use.
But not in this tutorial. I would recommend the third kind of compass. Let's
take a look at it:

But if you don't want to go north, but a different direction? Hang
on and I'll tell you.
You've got this "turnable" thing on your compass. We call it the Compass
housing.
On the edge of the compass housing, you will probably have a scale. From 0 to
360 or from 0 to 400. Those are the degrees or the azimuth (or you may
also call it the bearing in some contexts). And you should have the letters N,
S, W and E for North, South, West and East. If you want to go in a direction
between two of these, you would combine them. If you would like to go in a
direction just between North and West, you simply say: "I would like to go
Northwest ".
Let's use
that as an example: You want to go northwest. What you do, is that you find out
where on the compass housing northwest is. Then you turn the compass housing so
that northwest on the housing comes exactly there where the large direction
of travel-arrow meets the housing.
Hold the
compass in your hand. And you'll have to hold it quite flat, so that the compass
needle can turn. Then turn yourself, your hand, the entire compass, just make
sure the compass housing doesn't turn, and turn it until the compass needle is
aligned with the lines inside the compass housing.
Now, time to be careful!.
It is extremely important that the red, north part of the compass
needle points at north in the compass housing. If south points at north, you
would walk off in the exact opposite direction of what you want! And it's
a very common mistake among beginners. So always take a second look to make sure
you did it right!
A second problem might
be local magnetic attractions. If you are carrying something of iron or
something like that, it might disturb the arrow. Even a staple in your map might
be a problem. Make sure there is nothing of the sort around. There is a
possibility for magnetic attractions in the soil as well, "magnetic deviation",
but they are rarely seen. Might occur if you're in a mining district.
When you are sure you've got it right, walk off in the direction the direction of travel-arrow is pointing. To avoid getting off the course, make sure to look at the compass quite frequently, say every hundred meters at least. But you shouldn't stare down on the compass. Once you have the direction, aim on some point in the distance, and go there. But this gets more important when you use a map.
There is something you should look for to avoid going in the opposite direction: The Sun. At noon, the sun is roughly in South (or in the north on the southern hemisphere), so if you are heading north and have the sun in your face, it should ring a bell.
When do you need this technique? If you are out there without a
map, and you don't know where you are, but you know that there is a road, trail,
stream, river or something long and big you can't miss if you go in the right
direction. And you know in what direction you must go to get there, at least
approximately what direction.
Then all you need to do, is to turn the compass housing, so that the direction
you want to go in, is where the direction of travel-arrow meets the housing. And
follow the above steps.
But why isn't this sufficient? It is not very accurate. You are going in the
right direction, and you won't go around in circles, but you're very lucky if
you hit a small spot this way. And that's why I'm not talking about
declination here. And because that is something connected with the use of
maps. But if you have a mental image of the map and know what it is, do think
about it. But I think you won't be able to be so accurate so the declination
won't make a difference.
If you are taking a long hike in unfamiliar terrain, you should always carry a good map that covers the terrain. Especially if you are leaving the trail. It is in this interaction between the map and a compass, that the compass becomes really valuable.
This is the important lesson, and you should learn
it well.
It's when you use both compass and map the compass is really good, and you will
be able to navigate safely and accurately in terrain you've never been before
without following trails. But it'll take some training and experience, though.
I am not covering map reading here, guess you would have to consult other sources for that, but the lesson will be useful if you have a sense of what a map says.
Here is our compass again:

The principles are much the same above but this time, you are using the map to tell you which way is correct instead of your intuition.
Take a map. In our first example, we look at a map made for
orienteering, and it is very detailed. Well, not really. We look at a fictitious
map I drew myself, but never mind. To the point.
You want to go from
the trail-crossing at A, to the rock at B. Of
course, to use this method successfully, you'll have to know you really are
at A.
What you do, is that you put your compass on the map so that the edge of the
compass is at A. The edge you must be using, is the edge that is parallel to the
direction of travel arrow. And then, put B somewhere along the same edge, like
it is on the drawing. Of course, you could use the direction arrow itself, or
one of the parallel lines, but usually, it's more convenient to use the edge. At
this point, some instructors say that you should use a pencil and draw a line
along your course. I would recommend against it. First, it takes a lot of time,
but offers no enhancement in accuracy of the method. Second, if you have wet
weather, it may destroy your map, or if it is windy, you may loose it. You
should keep your map (preferably in a sealed) transparent plastic bag, and if it
is windy, tied up, so it can't blow away. But most important is that any
drawings may hide important details on the map.

Time to be careful again! The edge of the compass, or rather
the direction arrow, must point from A to
B! And again, if you do t his wrong, you'll walk off in the exact opposite
direction of what you want. So take a second look. Beginners often make
this mistake as well.
Keep the compass
steady on the map. What you are going to do next is that you are going to align
the orienting lines and the orienting arrow with the meridian lines of the map.
The lines on the map going north, that is. While you have the edge of the
compass carefully aligned from A to B, turn the compass housing so that the
orienting lines in the compass housing are aligned with the meridian lines on
the map. During this process, you don't mind what happens to the compass needle.
There
are a number of serious mistakes that can be made here. Let's take the problem
with going in the opposite direction first. Be absolutely certain
that you know where north is on the map, and be sure that the orienting arrow is
pointing towards the north on the map. Normally, north will be up on the map.
The possible mistake is to let the orienting arrow point towards the south on
the map.
And then, keep an eye on the the edge of the compass. If the edge isn't going
along the line from A to B when you have finished turning the compass housing,
you will have an error in your direction, and it can take you off your course.
When you are sure you have the compass housing right, you may take
the compass away from the map. And now, you can in fact read the azimuth off the
housing, from where the housing meets the direction arrow.
Be sure that the housing doesn't turn, before you reach your target B!
The final step is similar to what you did above.
Hold the compass in your hand. And
now you'll have to hold it quite flat, so that the compass needle can turn. Then
turn yourself, your hand, the entire compass, just make sure the compass housing
doesn't turn, and turn it until the compass needle is aligned with the lines
inside the compass housing.
The
mistake is again to let the compass needle point towards the south. The red part
of the compass needle must point at north in the compass housing, or
you'll go in the opposite direction.
It's time to walk off. But to do that with optimal accuracy,
you'll have to do that in a special way as well.
Hold the compass in your hand, with the needle well aligned with the orienting
arrow.
Then aim, as
careful as you can, in the direction the direction of travel-arrow is pointing.
Fix your eye on some special feature in the terrain as far as you can see in the
direction. Then go there. Be sure as you go that the compass housing doesn't
turn.
If you're in a dense forest, you might need to aim several times. Hopefully, you
will reach your target B when you do this.
At this time, you may want to go out and do some training, so you could check out some suggested exercises.
Unfortunately, sometimes, for some quite often, it is even more complicated. There is something called magnetic declination. And then, for hiking, you wouldn't use orienteering maps. And this is the issue for lesson 3.