1. Chapter 6 - Intro to Leveling Horizontal and Level Surfaces Datums Levels Level Rods Setting up the Level

2. Horizontal and Level Surfaces Vertical lines Follow gravity Converge Datum – reference at known distance from center of gravity Elevation – vertical distance above datum Level surface connects points of equal elevation Horizontal is perpendicular to Vertical

3. Datum Elevations Sea level NGVD 1929 NAVD 1988 “Above flood stage” Fargo – height over one of the dams Harwood - NAVD Assumed

4. Levels Dumpy Tilting Automatic Digital Laser

5. Dumpy Levels

6. Telescope Parts Reticle Cross-hairs Capstan’s screws

7. Focusing – Parallax Two focus adjustments Objective Eyepiece Both must focus on the reticle If not, image moves, or is out of focus Focus eyepiece while sighting on a white piece of paper before sighting on target

8. Automatic Levels Three-screw leveling foot Compensator

9. Digital Levels Automatic level Level rod: barcode Push button: Rod Reading Distance Microprocessor Set reference Internal Calculations

10. Laser Levels Low power Types Spinner Splitter Pipeline Receiver Indicates Hi/Low Clamps to rod Tied to Equipment

11. Level Rods Feet: larger numbers, red Tenths: black numbers Hundredths: black bar, 0.01’ thick. Tops: even, Bottoms: odd Feet: unknown 1/10ths: 0.1 1/100ths:.07 Read: X.17’

12. Level Rods Engineer’s Rod, Read to 0.01’ Builder’s Rod, Read to 1/8”

13. Reading the Rod Fig. 6-11, pg 116

14. Setting up the Level Tripod set firmly in ground No plumb bob – point not needed Level the level screws Pairs across Follow left thumb Lock in place Check Level