Back-sight

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Revision as of 14:12, 31 December 2007 by ChielOuvar (talk | contribs) (getracc)
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claboccvir A level observation, or sighting back, to a turning point or bench mark of known elevation. A transit observation on a previously located point in the rear. A fixed object in the rear which is sighted upon from time to time to check the orientation of the transit.