Introduction:
- Surveying may be defined as the method of making measurements of the relative positions of, natural & man-made features on earth’s surface and the presentation of this information either graphically or numerically.
- The commonest methods of presentation are by means of a plan or map.
- Both plans and maps are the graphical representations of the features on a horizontal plane.
- Plan is a large scale representation whereas man is a small scale representation.
- Height information can be added either as spot heights, which are individual heights of points, or as contours which give a less detailed but better visual representation of the area.
Plane & Geodetic Surveying:
- Surveying is divided primarily into Geodetic & Plane surveying.
- In Geodetic surveying, large areas of earth’s surface are involved & curvature of earth is taken into account.
- In plane surveying, relatively small areas are under consideration, and it is assumed that the earth’s surface is flat.
- In Plan surveying, measurement plotted will represent the projection on the horizontal plane of the actual field measurements.
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