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Webster 1913 Edition
Backsight
Back′sightˊ
(băk′sītˊ)
, Noun.
[
Back
, adv. + sight
.] (Surv.)
The reading of the leveling staff in its unchanged position when the leveling instrument has been taken to a new position; a sight directed backwards to a station previously occupied. Cf. , 3.
Foresight
, Noun.