witness mark n.— «With a rule draw out a witness mark from each saw cut on the surfaced side of the line boards and plainly write there-on a brief designation of what line of the building the saw cut is on, as “Brick Line...
witness mark n. generally, an intentional, accidental, or naturally occurring spot, line, groove, or other contrasting area that serves as an indicator of certain facts; in geography and surveying, a blaze, cut, hole, paint splash, or message...
witness post n.— «As surveys progressed, various improvements were introduced to secure regularity and convenience of description, by the establishment of base-lines, meridians, and standard parallels, through certain permanent natural...
drying rock n. a rock in the sea whose exposed surface at low tide is used as a marker for surveying or establishing legal boundaries. Also low-tide elevation. (source: Double-Tongued Dictionary)