Surveying is the art and science of locating points in horizontal and vertical planes on the surface of the earth. There are two basic principles of surveying.
To work from whole to part
This is to achieve the best possible accuracy. If we start from smaller areas and then prepare a bigger map then there are chances of a greater accumulation of errors. Working from whole to part helps in reducing the errors.
Locate any point on the ground using two known points
To locate any other point on the field using knowledge of the position of at least two well-established points on the ground.
We can locate the third point by either of the following methods.
- By measurement of one angle and one linear distance.
- By using two angular measurements.
- With the help of two linear distances.