4. Position compass at eye level and sight through
the sight hole.
5. Pivot your body until reflection of the
blue
orienting circle outlines
red
circled "N" (figures
12 & 13).
· Do not rotate the azimuth ring.
6. Sight destination or object through sight hole.
7. Travel to destination or object.
Always sight a destination or object in the distance.
Do not follow compass bearing by watching the
compass. If final destination is too far away to see,
sight a tree, mountain or something else and walk
to the object. At object, re-sight compass bearing to another object.
Repeat until final destination is reached.
6 – Topographic Map
A topographic map (topo-map) is a 2-dimensional drawing of 3-dimensional terrain. Hills, valleys,
ridges, cliffs and other terrain are represented through a series of contour lines. Each line
represents constant elevation in meters or feet above sea level. The contour interval (vertical
distance) between each line is indicated in the legend of the topographic map. Lines positioned
close together indicate a rapid change in elevation, while lines further apart indicate a more gradual
change in elevation.
7 – Map Bearing
Whether in the field or at home, it is possible to determine a bearing from one position to another
directly from a map. The following instructions provide two methods of finding map bearings – map
alignment and compass alignment.
7.1 Map Alignment
Using this method, you align a topo-map to true north, then it is possible to find a map bearing.
Figure 12
90
270
Figure 13
With practice, you'll begin to rec-
ognize many different contours
on a topo-map, and identify the
best possible route from one
position to another (figure 14).
In addition, by studying the map
it will be possible to identify
landmarks and determine
positions, bearings and
distances.
Figure 14
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This is a popular method because it is possible to compare the map to the actual terrain. The
following examples use a USGS topographic map.
1. Remove rubber shoe.
2. Adjust for magnetic declination.
3. Rotate azimuth ring until compass bearing reads 0°,
green
scale (figure 15).
4. With mirrored end of compass pointing to true north on
the map, place the clear base along the map's margin
(edge of printed map - figure 16).
· On maps other than USGS or BLM, true north may
not be aligned with the map's margin, so it might be
necessary to place the clear base next to the true
north indicator, on the map.
0
Figure 16
5. Rotate map until
blue
orienting circle outlines the
· The compass base should remain along the map's margin.
180
0
Figure 15
red
circled "N" (figure 16).
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