Surveying
To avoid large centering error with very short legs, observations are generally made

To a target fixed on theodolite tripod on which theodolite may be fitted easily
By using optical system for centering the theodolite
All listed here
To chain pins

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Surveying
The rise and fall method

is not suitable for levelling with tilting levels
provides a check on the reduction of intermediate point levels
is less accurate than height of instrument method
quicker and less tedious for large number of intermediate sights

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