Quadrant

in gunnery, an instrument made of bra or wood, divided into degrees, and each degree into 10 parts, to lay guns or mortars to any angle of elevation. The common sort is that whose radii project the quadrant about 12 inches, and whose plummet suspends in its centre, by means of a fine piece of silk; so that, when the long end is introduced into the piece, the plummet shows its elevation. The best sort has a spiral level fixed to a bra radius; so that, when the long end is introduced into the piece, this radius is turned about its centre till it is level: then its end shews the angle of elevation, or the inclination from the horizon; whereas the first shows that angle from the vertical. See Level .