A treatise on surveying, comprising the theory and the practice ; (1887)
Gillespie, W. M. (William Mitchell), 1816-1868, Staley, Cady, 1840- [from old catalog] ed · New York, D. Appleton and company · leaf 468
with stones ; and Fig. 507 shows it with the staff turned aside, tomake room for the theodolite and its protecting tent. The heightsof these signals varied between fifteen and eighty feet. Another good signal consists of a stout post let into the ground,with a mast fastened to it by a bolt below…
Surveying
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