A Treatise on Surveying and Navigation. (Logarithms.).

angular points azimuth barometer called chains chronometer circle circumferentor compass computed correction corresponding cos.a Cosine Cotang course and distance decimal degree Diff difference of longitude direction divide draw earth east equal equation example feet figure give given point Greenwich height horizontal parallax hypotenuse inches instrument land latitude and departure Let ABC limb lines drawn logarithm longitude by chronometer mean measure meridian distance meridian line miles moon's multiply N.sine Nautical Almanac needle noon object observations parallel perpendicular plane plane sailing polar distance polygon problem radius random line represent right angles right ascension screw semi-diameter setting and drift sextant ship sail side sin.b sine spherical trigonometry square star stations subtract sun's suppose survey surveyor Tang tangent telescope temperature theodolite trapezoid trigonometry true altitude vernier vernier scale Whence