When adjusting a traverse that starts and ends on two different stations, surveyors compute the
coordinates before the error is determined. The correction (per leg) is determined in the same manner,
but is applied directly to the coordinates. The correction to be applied after computing the first leg is
equal to the correction computed for the first leg. The correction to be applied after computing the
second leg is equal to the correction computed for the first leg plus the correction computed for the
second leg. The correction for the third leg equals the correction computed for the first, second, and
third leg. This method continues throughout the traverse. The final correction must be equal to the total
correction required.
x. Special Instructions. A good observer consistently secures accurate results, as permitted by the
capabilities of the instrument used. To attain proficiency, the surveyor must study the instrument
carefully, exercise good judgment, and carefully study all factors affecting the accuracy of theodolite
observations. The different classes of errors should also be taken into consideration. In order to obtain
the best results, observe the following precautions:
Adjust and level the instrument carefully before proceeding with the measurement.
Keep away from the tripod when making a measurement.
Turn the plates gently. Hold the plates or limbs, not the telescope.
Work steadily and carefully. Do not rush.
Do not screw on the tripod legs too tightly.
Do not turn clamps or leveling screws too tightly.
Leave the horizontal axis lightly clamped during horizontal-angle observation.
Leave the lower motion unclamped during vertical-angle observations.
Never carry the theodolite by its tripod.
Direct the recorder to immediately record all readings in the notebook, while calling back the
figures clearly and promptly.
Cultivate the impersonal attitude toward results, and read the angles without bias. An angle
forced in order to give a good triangle closure will often cause a large angle and side
correction when the adjustment is made.
3-15. Traits of a Good Recorder. A good recorder must be able to work quickly and accurately.
Recorders should be thoroughly familiar with all phases of reading angles and recording them. They
should have sufficient mathematical knowledge to
EN0593
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