following are suggested as approximate safe distances
clicking device. Turning the bezel ring to the left causes
to ensure proper functioning of the compass:
an increase in azimuth, while turning it to the right
causes a decrease. The bezel has a stop and spring that
High tension power lines . . . . . . . . 55 yards
allows clockwise and counterclockwise turns at 3
intervals per click and holds the bezel ring in any desired
Field gun, truck, or tank . . . . . . . . 18 yards
position. One method for determining compass
directions at night is as follows:
Telegraph and telephone wires and
1. Rotate the bezel until the luminous line is over
10 yards
barbed wire . . . . . . . . . . . . . . .
the black index line.
2 yards
Machine gun . . . . . . . . . . . . . .
2. Hold the compass with the left hand and
continue to rotate the bezel ring with the right hand in a
Helmet or rifle . . . . . . . . . . . . . 0.5 yards
counterclockwise direction for the number of clicks
required. The number of clicks is determined by
Nonmagnetic metals and alloys do not affect
dividing the value of the required azimuth by 3. For
compass readings.
example, for an azimuth of 51, the bezel ring is rotated
5. Practice by using the compass at regular
17 clicks counterclockwise.
intervals. This is to help you become competent in its
3. Turn the compass until the north arrow is
use during an emergency.
directly under the luminous line on the bezel.
4. Hold the compass open and level in the palm of
the left hand with the thumb along the flat side of the
Azimuth and Back Azimuth
compass. In this manner, the compass can be held
consistently in the same position. Position the compass
The most common military method of expressing a
approximately halfway between the chin and the belt,
direction is by using azimuths. As stated before, an
pointing directly ahead of yourself. A little practice in
"azimuth" is defined as a horizontal angle, measured in
daylight should make you proficient in pointing the
a clockwise reamer from a north base line. When the
compass the same way every time. Looking directly
azimuth between two points on a map is desired, the
down into the compass, turn your body until the north
points are joined by a straight line. Then a protractor is
arrow is under the luminous line. Then move forward in
used to measure the angle between grid north and the
the direction of the front cover luminous sighting dots
drawn line. This measured angle is the grid azimuth of
(fig. 5-26).
the drawn line (fig. 5-29). When using an azimuth, you
imagine the point from which the azimuth originates as
Certain precautions about the care and use of a
lensatic compass are important because they assure,
within reason, that a compass works when and where
you need it.
1. Handle the compass with care. The dial is set at
such a delicate balance that a shock could damage the
compass.
2. Close and return the compass to its special
container when it is not in use. In this way, it is not only
protected from possible damage but is readily available
for use when needed.
3. When the compass is to be used in darkness, an
initial azimuth should be set, whenever possible, while
light is still available. With this initial azimuth as a base,
you can read any other azimuth that is a multiple of 3
by using the clicking feature of the bezel.
4. Compass readings should NEVER be taken near
Figure 5-29.--Azimuth angle.
visible masses of iron or electrical circuits. The
5-21
