Definition of Surveying
The art of determining the relative positions of distinctive features on the surface of earth or beneath the surface of the earth, by means of measurements of distances, directions and elevations is called surveying
Primary Divisions of Surveying
Surveying may primarily be divided into two divisions:
- Plane surveying. The surveys in which earth surface is assumed as plane and the curvature of the earth is ignored, are known as Plane surveys.
- Geodetic surveying. The surveys in which curvature of the- earth is taken into account and higher degree of accuracy in linear and angular observations, is achieved, are known as Geodetic surveys.
Principle of Surveying
The main principle of surveying whether plane or geodetic is to work from the whole to part. To achieve this in actual practice, sufficient number of primary control points are established with higher precision in and around the area to be detailed surveyed. Minor control points in between primary control stations, are then established with less precision method. The details are surveyed with the help of these minor control points, adopting any one of the methods of surveying. The main idea of surveying from the whole to the part, is to prevent accumulation of errors and to localise the minor errors in the frame work of the control points.
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