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 38
emicircle of brass, as in thefigure, with its semi-circumference divided into 180 equal parts, ordegrees, and numbered in both directions. It is, in fact, a minia-ture of the instrument (or of half of it) with which the angles havebeen measured. To lay off any angle at any point of a straightline,… … 24 LAN3-SUR TEYIXG. needle or sharp pencil make a mark on the paper at the requirednumber of degrees, and draw a line from the mark to the givenpoint. Sometimes the protractor has an arm turning on its center and Fig. 21.
Surveying
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
