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precise angular measurements for triangulation in road building, tunnel
alignment, and other civil-engineering work.
The most important elements of a theodolite are shown on the
picture.

Figure 10.9. Theodolite

Before using theodolite must be centred and_______. The next
steps are appropriate:

1. Setting up the tripod (the head of the tripod should be
approximately horizontal) above the________.
2. Fix the instrument on the tripod.

3. Sight the station point in the optical plummet using the foot
screws of the instrument.
4. Level the instrument by _______the length of the legs of the
tripod using the circular bubble.

5. Find the normal point of the bubble tube.
6. Level the instrument accurately using the bubble tube and the
three levelling screws.

7. Finally loosen the instrument_______, and slide it above the
station point on the head of the tripod.
8. Fix the instrument on the tripod.
There are different types of theodolites: electromic, optical

teodolites, phototeodolite, transit and others. The transit is a variety of
theodolite that has the telescope so mounted that it can be completely
reversed, or transited. The phototheodolite, a combination camera and

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