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Section 1  Preparing to Build
like the one shown, have legs whose length can
be independently adjusted. This feature makes
the tripod easier to level on sloping ground. It
also permits the legs to be shortened for easier
handling and storing.
When sighting over long distances, use a
leveling rod. See Figure 6-8. It is a long rod
marked off with numbered graduations. It allows
differences in elevation between the position of
the level and various positions where the rod
is held to be easily read. The rod is especially
useful for surveying. The person operating the
level can make the readings or the target can be
adjusted up and down to the line of sight and
then the person holding the rod (rod holder) can
make the reading.
Tripod head
Leg
Ground spike
Tie strap
Leg clamp
Figure 6-7. Tripod legs hinge at top and are adjustable
for use on uneven terrain. (David White)
Eyepiece
Horizontal
clamp screw
Vertical
tangent screw
Vertical
clamp screw
Vertical
arc
Focusing knob
Index vernier
Horizontal
graduated circle
Telescope lens
Figure 6-6. A transit can be used to lay out or check
both level and plumb lines. It can also be used to
measure angles in either the horizontal or vertical
planes. (David White)
Leveling rod:  A long rod marked off with numbered
graduations that is used, along with a builder’s level
or transit, to sight differences in elevation over long
distances.
A B
Figure 6-8. Leveling rod with target. The target can
be moved up or down to match the line of sight of the
transit. (David White)