It is very common, in our daily life to measure the difference between heights of two or more sights, points or spots. Sometimes we have to mark on the ground same points of same height. For example, If we want to built house on sloping side of hill, then we have to mark point of equal-altitude.
Similarly when we build cannel in farm, we need to check proper slope so that water will flow easily by gravity. We also check slope, while transporting water from one spot to other. Water conservation works are carried on the on barren sloppy land. Trenches and bunds are constructed on the slopping land. They constructed on the point of same height. “The imaginary line joining all points of the same point on the ground is called as contour line”. Also we will learn about leveling, different types of instruments used for leveling and drawing of contour lines.
After the completion of this lesson you will be able to:
- use the instruments like spirit level, leveling tube, Dumpy Level.
- apply the method to mark Contours for a small watershed and check dams.