| Compass Basics |
| This page is just an introduction to the compass.
For more practical uses (e.g. bearings) see the relevant sections
on the main menu.
There are several different types of compass available. These
may range from the simple 'toy' compass which has a fixed
dial to the more technical prismatic compass. Here we will
concentrate on the most suitable compass for scouting, the
orienteering type compass.
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Darren Dowling
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| Connected |
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Connected is a central area that provides links to obtain
further information on subjects contained in Scouting Resources.
From here you can go on to websites related to your area of
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| Typical Compass |
Darren Dowling
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Basic Compass
A typical (Silva type) compass consists of a magnetic strip
of metal, suspended or pivoted (so it can swing freely) within
a moveable dial construction. The dial is usually liquid filled
(this dampens the oscillation of the needle allowing it to
settle into position much more quickly) and has several parallel
lines marked on the dial itself. The compass should have a
clear plastic base plate with straight edges. Along the edges
should be scales in both metric (cm and mm) and imperial (inches).
Some may have additional features such as a magnifying area
and degrees of declination/magnetic variation (usually marked
on the compass dial). A wrist strap is another important feature
if you want to keep the compass.
There are usually 3 different types of arrow marked on the
compass. As indicated in the diagram, the vertical arrow marked
on the plastic background is your direction of travel arrow.
This is the only arrow you ever follow.
The arrow that spins in the middle of the compass (usually
coloured red and white) always turns to point north (the red
end is the end that points north). NEVER follow this arrow
(because you will always be walking north then, no matter
where you actually wanted to go!) When using a compass try
not to hold it near any metal or any magnets else this arrow
will be attracted to them and you will end up going in the
wrong direction. Depending on where you are simply placing
the compass near the floor may give you an inaccurate reading
due to iron and mineral deposits in the ground. Always check
you have the same reading at ground level and when standing
up.
The third arrow is the one that will be marked upon the dial.
(you cant actually see this on the picture). It is usually
a red arrow marked on the bottom of the dial. This is the
one that will match up with the red and white pointer that
spins. When you want to read a number off the dial, look at
the point where it touches the line at the top (the one marked
by read bearing here), this is the number you
want.
NOTE: There are 360 degrees in a
circle. Be careful about how many degrees each line on the
compass represents. Normally on compasses of this type each
line is worth 2 degrees. This is important as
a difference of 5 degrees over a walk of 6 miles will mean
you will be about half a mile from where you should be!
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| Compass Points |
Darren Dowling
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All you have to remember are the four main
points of the compass. All the other points are made by combining
these four. (for instance halfway between north and east is
northeast).

Compass Points
Some silly ways to remember the order of the points are to
recall the following phrases. The points start at the top
and go around clockwise.
Never Eat Shredded Wheat
Naughty Elephants Squirt Water
If you wish to quote a more accurate direction you can either
opt for a more complicated compass point;
North by Northeast is a position halfway between north and
northeast. Note that the convention for naming points of this
type is to quote the 'more important' compass point first.
For example, halfway between southwest and west would be called
West by Southwest (and not Southwest - West).
or you can resort to quoting an angle
measured clockwise from North (in degrees);
Recall there are 360° in a circle. So North would be
0°. East would be 90°. South - 180° and West 270°.
As another example, Northeast would be 45° (halfway between
north and east).
The advantage of quoting in degrees is speed and accuracy
(a direction of 208° is not an obvious compass point!).
This is related to bearings.
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