QUADRANT of Altitude, is an appendage of the artificial globe, consisting of a lamina, or slip of brass, the length of a quadrant of one of the great circles of the globe, and graduated. At the end, where the division terminates, is a nut rivetted on, and furnished with a screw, by means whereof the instrument is fitted on the meridian, and moveable round upon the rivet to all points of the horizon.—Its use is to serve as a scale in
measuring altitudes, amplitudes, azimuths, &c. See QUADRANTAL.