Distance Between Two
    Points
 Pacing
 Chaining
 Temperature
 Standardisation
 Catenary
 Slope
 Tension
 Tachaeometry
 Stadia System
 Measurement of
    Tacheometric Constants
 Refraction and Curvature
 Theodolite
    Tachaeometry
 Field Tachaeometry
 Electronic Tachaeometry

Refraction and Curvature

In order to avoid errors due to differential refraction of light through the atmosphere, the lower stadia reading should not be too low on hot days, generally not less than 0.5m. With respect to earth curvature both stadia readings are equally affected and there is no effect on the value of the intercept. Correction for curvature on the distance and level should be applied if the sight lengths are long enough.

Where are students shown how to correct for curvature on the distance somewhere else?