. A treatise on surveying and navigation: uniting the theoretical, the practical, and the educational features of these subjects. y the learner, we therefore give the following minute illus-tration of it. Let the reader now face the north with the booh open before him, hisright hand is then toward the east, and his left hand toward thewest. The following fig-ure represents thecompass set to themagnetic meridian,that is the sight-vanesVv and the needlelie in the same direc-tion. The degrees onthe plate are num-bered both ways fromifand/Stoifand W. At the first viewof this subject, it hassurpris
. A treatise on surveying and navigation: uniting the theoretical, the practical, and the educational features of these subjects. y the learner, we therefore give the following minute illus-tration of it. Let the reader now face the north with the booh open before him, hisright hand is then toward the east, and his left hand toward thewest. The following fig-ure represents thecompass set to themagnetic meridian,that is the sight-vanesVv and the needlelie in the same direc-tion. The degrees onthe plate are num-bered both ways fromifand/Stoifand W. At the first viewof this subject, it hassurprised many tofind Wfor west on theright hand toward theeast, and E in thedirection toward the west. The reason of this is explained by thenext figure. Suppose we wished to find the direction of a line from the centerof the compass to the object B. We set the compass, that isplace it horizontal on its staff or tripod, the needle will take thesame direction as in the first figure, parallel to the margin of thepaper. The sight-vanes Vv are turned toward the object B which turnsthe whole plate, but the needle retains its 84 SURVEYING
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Keywords: ., boo, bookcentury1800, booksubjectnavigation, booksubjectsurveying
