Describe the method of locating contours by square method.
1) The method of square is indirect method of locating contours.
2) The method of squares is used where the area to be surveyed is small and not much undulating.
3) The area to be surveyed is divided into squares of size varying 5m to 20m. The size of the square depends upon the nature of ground.
4) The reduced level of the corners of squares (called nodal points) is determined by levelling.
5) The squares are plotted with suitable scale and the calculated reduced levels of these nodal points are written on the respective corners.
6) The contours are then interpolated between them.