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shadow bar which has
make foresights
and maintain.
Using
(4)
the
The sun
(a)
from Polaris (north star). Figure
mining north
the
constellation
Minor, of
which
dipper),
and two other constellations, the Great
—
Major)
Ursa
name
Dipper
Great
because
A
pair
stars.
handle are called
Polaris.
points
at
Ursa Major
constellations
in
figure
shown
an observer north
by
(b) Orienting
(1) Screw the three-inch
in
hole provided
Loosen the clamping nut and
(2)
mark
on
degree
mined azimuth.
Turn
the
(5)
sighting rod and the gnomon rod.
right
course.
the
on
(c) Determining Unknown
Turn
the date bar
(1)
rod and the gnomon rod are in alignment
arrow
on the date bar is now
The
unknown
(2)
is
from
taken
points to the
degree
Using
(d)
Stars
near
However,
these
Polaris
intervals
at
by
OPERATION
properly
been
reference points are
because
Sun Compass at Night.
may also
compass
Little
"The
Polaris is
the
and Cassiopeia.
of
the outline formed
of
on
these
the
"pointers"
the
Polaris
lies about
and Cassiopeia.
are easily recognized
8
of
the tropics.
the Vehicle
radium
the date bar.
protractor
the
until Polaris is
vehicle
until
pointing
azimuth
the protractor.
mark which represents the azimuth.
Stars
Foresights.
as
the
horizon
and the azimuth should
stars
move
of
minutes.
15
It
set.
difficult
at night
be used
Dipper"
(Latin
star in
the handle
end
Ursa Major
by
of
side
the bowl opposite the
line
because a
halfway
All
during
Predetermined
to a
tipped sighting rod
turn
the date bar to the
which represents the predeter
aligned
The
vehicle
Azimuths.
tips of
the luminous
with Polaris.
approximately
in
which
the
arrow
The
may
be
used
10
is
impossible to
to observe
by
deter
Polaris,
shows
8
—
Ursa
name
of
the
Dipper
(Latin
is
called the
its
bright
seven
connecting them,
between the
of
stars
these
any clear night
Azimuth.
into
the
with
the short
is
now
headed
the sighting
The
true north.
is
vehicle
headed
bar
on the date
as foresights.
be checked
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