TM 1-1680-359-10
2-7. OPERATING PROCEDURE (Cont)
NOTE
Items which contain iron or steel, or other types of compasses, will cause the lensatic
compass to give incorrect readings.
(1)
Hold the compass erect so that the lubber line is parallel to your line of sight:
(2)
Turn the plastic top until the lubber line is over the NORTH arrow. Your course heading may then
be read on a line drawn through the sights.
g.
EMERGENCY SIGNALING MIRROR. The signal mirror is a glass signaling instrument equipped with a
retaining cord on one corner and a see-through sighting device in the center of the glass. When used in daytime and
with good visibility, a mirror flash can be seen at a distance of 30 miles at an altitude of 10,000 feet. Though less
effective, and with possible shorter range, mirror flashes can also be seen on cloudy days with limited visibility. To use
the mirror, proceed as follows:
2-33
