Wentworth, G. A. (George Albert), 1835-1906 · Boston, Ginn & company · leaf 230
Fig. 42. 58 SURVEYING. If a greater height than 6-J- feet is desired, the target ismade fast with its horizontal line at 6^ feet from the lowerend. The back part of the rod is then moved up until thetarget is at the required height, and the reading is taken atthe side of the rod. When fully…
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