Survey 1

Measuring vertical distances (leveling)

You want to know levels (altitudes) along the roads depicted on the picture. The purpose might be to prepare a project for laying down pipes for sewer or controlling the level of road surface during construction. The survey is closed in order to have a check against errors.

Map of location around Zaman University

The result will be

From the plan should be also clear

Equipment and procedure

We work with

The instrument should be placed somewhere around the middle between BS and FS. BS is of known altitude. Then all 3 wires are read by telescope for each backsight and foresight rod. Thus height of the instrument (HI) and height of the FS is determined.

By means of level instrument and rods, we are able to find out

  1. Relative vertical distances are evaluated from comparing the reading of backsight BS (known altitude) against foresight FS (unknown altitude to be determined by the measurement).
  2. Once measurement of both BS and FS is completed (and altitude of FS is determined) the instrument is moved over turning point (that means over the FS) to a new position to establish new setup.
  3. FS remains at the same position and becomes BS of known altitude needed for the next step.
  4. New FS of unknown altitude is established at desired point and measured against BS then.

For each reading, all 3 wires from crosshair are recorded. The purpose is A. better precision, B. protection against errors/blunders, C. distances can be evaluated as well.

When using level instrument, approximate distance between the instrument and the rod is evaluated from reading upper against lower wire of crosshair. The difference is multiplied by 100 (the magnifier of our instrument) to get distance in metres.

Important notes


Since we have no benchmark points, you are free to fix altitude of the starting point according to your judgement.

List of chapters