FHIG123AG Outdoor | 69stream towards it. Staggeringly, this led to a path,
which took me to the hut. I was very lucky. A
young woman disappeared in the exact same
area a few months later, and so far – over 15 years
later – her body has never been found.
Lesson one: always chuck a compass into your
backpack, no matter how minor your mission
might seem.
Lesson two: learn how to use it – at least mas-
ter the basics – and pair it with a good quality
topographical map.
HOW DOES IT WORK?
The kind of compass most commonly used by
outdoors people, from army personnel to week-
end walkers, is a magnetic compass. This device
is defined by its key component: a magnetised
needle, which spins freely within a housing, with
one end constantly drawn towards Earth’s mag-
netic north pole. The north-facing half of the
needle is usually red, inscribed with an ‘N’ and
has a luminous strip for navigating in the dark.
A classic protractor-style Silva compass is
comprised of two elements: the ‘baseplate’,
which has various features handy for map read-
ing and wayfinding, and the ‘housing’, where all
the technical magic happens.
The baseplate should be made from clear plas-
tic, so you can clearly see the map through it,
and it will have a ‘Direction of Travel Arrow’ at the
top, complete with a luminous strip.
Baseplates are typically inscribed with
standard ruler measurements (mm) plus scale
converters along the sides (showing, for example,
that on a 1:50,000 map, 1cm represents 500m on
the ground). Other common features include a
‘Magnifying Lens’, for looking at maps in detail,
and ‘Aid Lines’ to help you set your map or take a
bearing.
Mounted on the baseplate is the housing,
where the magnetised needle lives. The housing
on a good quality magnetic compass will contain
a clear fluid, which slightly dampens the move-
ment of the needle, allowing it to settle steadily
once it has a fix. This also means you can be in
motion – walking, running, cycling, paddling,
space hopping, whatever – without the needle
skittishly twitching.As well as containing the floating needle, the
compass housing has the cardinal points of the
compass rose – N (north), S (south), E (east) and
W (west) – printed on a rotating circular bezel,
along with graduation markers indicating
degrees (0-360).
On the bottom of the housing is an ‘Orienting
Arrow’, which moves when the bezel is rotated
but permanently points towards ‘N’ (north) on
the housing. Running parallel to this you’ll see
‘Orienting Lines’, which also rotate with the bezel
and are designed to be aligned with the vertical
North-South grid lines on maps. The top half of
both the Orienting Arrow and the Orienting
Lines are red, to indicate north.
Finally, there’s an ‘Index Line’ (or ‘Dash’), fixed
on the top edge of the compass housing,
beneath the rotating bezel, which aligns with the
direction of travel arrow on the baseplate. This
doesn’t move, so it marks the bearing set when
the compass housing is rotated.
So, if you stand facing due north – with the
Direction of Travel Arrow, the Index Line, the
Orienting Arrow and the needle all aligned – N
will be at 0 degrees on the bezel, E will be at 90,
S at 180 and W at 270. If you do this whilst also
aligning the orienting lines on the compass
housing with the North-South grid lines on your
map, then your map will be correctly ‘set’ – i.e.,
facing the same way as the physical terrain that is
in front of you – which is always a very good
thing to do at the outset of an adventure, andGPS is a great tool, and excellent for recording routes,
but when you need something failsafe to get out of
strife, a magnetic compass is your best mate.
Clockwise from left To follow a bearing
accurately, you need to factor in magnetic
declination; Orienteers, rogainers and adventure
racers often use lightweight thumb compasses to
navigate on the run.SCALE: 1:1, 425, 000
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