are graduated in feet and decimals of feet, but some are graduated in feet and inches, meters, or other
linear units. Steel tapes are sometimes equipped with a reel on which they can be wound. These tapes
can be, and often are, detached from the reel for more convenient use in taping.
Figure 5-8. Surveying tapes
5-4. Surveying Accessories. Surveying accessories include the equipment, tools, and other devices
used in surveying that are not considered to be an integral part of the surveying instrument itself. For
example, when you run a traverse, your primary instruments may be the theodolite and the steel tape.
The accessories you will need to do the actual measurement are-
A tripod to support the theodolite.
A range pole to sight on.
A plumb bob to center the instrument on the point.
Tape supports to support the tape from sagging if the survey is of high precision.
It is important that you become familiar with the proper care of this equipment and use it properly.
a. Tripod. The tripod is the base or foundation that supports the surveying instrument and
keeps it stable during observations. A tripod consists of a head to which the instrument is attached, three
wooden or metal legs that are hinged at the head, and pointed metal shoes on each leg to be pressed or
anchored into the ground to achieve a firm setup (see Figure 5-9, page 5-10). The leg hinge is adjusted
so that the leg will just begin to fall slowly when it is raised to an angle of about 45€. The tripod head
may have screw threads on which the instrument is mounted directly, a screw protecting upward through
the plate, or a hole or slot through which a special bolt is inserted to attach to the instrument. When
mounting the instrument on the tripod, firmly grip it to avoid dropping it. Hold the theodolite by the
5-9
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