A treatise on levelling, topography, and higher surveying (1876)
Gillespie, W. M. (William Mitchell), 1816-1868, Staley, Cady, b. 1840, ed · New York, D. Appleton and company · leaf 143
124: LEVELLING, TOPOGRAPHY, AND HIGHER SURVEYING. (195.) Otherwise. At A set off an angle, asCAD (ADbeing a prolongation of AB). Then walk along the line A Cwith the index set to half that angle, looking at A directly,and B by reflection, till yon come to some point, 0, at whichthey coincide. Then… … the angle A C B. Set the sextant to half that angle, and. walkback in the line B C prolonged till at some point, D, A and Bare seen to coincide, as in last problem; thus making A C =C D. Do the same on A C produced to some point, E. ThenisDE = AB. (197.) All the methods for overcoming obstacles to…
Surveying
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
