Drawing instruments eg T-Square

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Another Logic Mill card

Drawing instruments eg T-Square -- Levels, Compasses, sextants and drawing instrument theodolites: An optical instrument consisting of a small mounted telescope rotatable in horizontal and vertical planes, used to measure angles in surveying, meteorology, and navigation. Circumferentor archaic Circumferenters - A surveying instrument, for taking horizontal angles and bearings; a surveyor's compass. It consists of a compass whose needle plays over a circle graduated to 360°, and of a horizontal brass bar at the ends of which are standards with narrow slits for sighting, supported on a tripod by a ball and socket joint.