Hand level

a type of minor levelling instrument.

1. Hand Level By : Durgesh Kumar Yadav

2. Definition A hand level is a tool used for rough levelling i.e. estimation not precision.

3. Construction It mainly consists of :- A telescope ( 10 to 15cm long). Spirit level. Eye piece. Object lense . Reflecting mirror having half width of the instrument. Cross wire. Focusing screw.

4. How to Use the Hand Level Steps :- Hold the instrument in hand at the eye level. Raise/ lower object end till the image of bubble seen in the reflecting mirror is bisected by cross wire. Take the staff readings against cross wire.

5. How to Use the Hand Level

6. Adjustment of Hand Level

7. Setting & Levelling of HAND LEVEL Bubble of spirit level should be at center. Instrument & line of sight should be horizontal. For greater stability : Use of “forked bush pole”

8. Uses of Hand level Mainly it is used for rough levelling in small scale work but it can be used for : Setting out contour lines. Measuring difference in elevation b/w two points.

9. Setting out Contour Lines Fig. Determination of Height of the level

10. Setting out Contour Lines

11. Setting out Contour Lines

12. Measuring Difference in Elevation Measuring difference in elevation b/w two close points.

13. Measuring Difference in Elevation Measuring the difference in elevation b/w two distant points.

14. Measuring Difference in Elevation Formula : Difference in elevation b/w A & B = sum of back sight readings – sum of fore sight readings If + ve then A<B If – ve then A>B

15. Advantages of Hand Level Cheap as compared to other levelling instruments. Portable. Less time taking. Easy operation.

16. Disadvantages of Hand Level Less accurate as compared to other levelling instruments. Suitable for only small scale work.

17. Thank You ! Keep smiling…

18. The end