1.5. Basic Principles of Surveying

The basic principle of surveying are 
 i. Working from whole to part 
 ii. Location of a point by measurement from two control points

The principles of surveying are explained below:

I. Working from whole to part:

 According to this principle when area is to be surveyed first a system of control points is to be established covering the whole area with high precision then minor details are located by less precise method.

II. Location of a point by measurement from two control points

According to this principle the relative position of a point to be surveyed should be located by measurement from at least two points of reference the position of which have already been fixed.

Here, P and Q are control points and R is to be surveyed.