Measurement of Vert. Distances

A fixed point of reference whose elevation is either known or assumed. They may be permanent or temporary.

• Foresight

• Bench Mark

• Turning Point

• Backsight

A reading taken on a rod held on a point of known or assumed elevation. It is always the first rod reading

taken after the instrument has been set up and leveled.

• Backsight

• Foresight

• Turning Point

• Bench Mark

A reading taken on a rod held on a point whose elevation is to be determined.

• Height of Instrument

• Foresight

• Backsight

• Turning Point

Measured from the center of the instrument to the rod on which a backsight is taken

• Backsight

• Backsight Distance

• Foresight

• Foresight Distance

A curved line which graphically portrays the intersection of a vertical plane with the surface of the earth.

• Profile

• Stationing

• Full Station

• Plus Station

Any other intermediate point established along a profile level route which is not designated as a full station.

• Stationing

• Profile

• Full Station

• Plus Station

The process of determining differences in elevation along a fixed line at designated short measured intervals.

• Profile Leveling

• Differential Leveling

• Double-Rodded Leveling

• Three-Wire Leveling

A method of determining differences in elevation wherein three horizontal hairs are read and recorded rather than from a single horizontal hair. A more precise method of differential leveling

• Three-Wire Leveling

• Profile Leveling

• Double Rodded Leveling

• Differential Leveling

The process of determining the difference in elevation between two or more points some

distance apart.

• Three-Wire Leveling

• Double-Rodded Leveling

• Profile Leveling

• Differential Leveling

A process of drawing the vertical scale for a profile much larger than the horizontal scale in order to accentuate the differences in elevation.

• Vertical Exaggeration

• Vertical Stationing

• Vertical Profile