model of astronomical instrument in the Jaipur observatory: double mural quadrant (Dakshinobhitti Yantra), scale 1:24
The masonry wall is accurately places in the meridian, or north to south line. On the east dace are inscribed two quadrants of 20 feet radius and on the west face a semicircle of 19 feet 10 inches radius. The arcs and graduations are of lead inlaid in marble. Pegs are fixed at the centres of the arcs to which a thread can be attached for observing. Steps give access to the higher parts of the arcs. The instrument is used for observing the altitudes of heavenly bodies when on the meridian.
This instrument was built in 1876 to replace a similar one which was pulled down to make room for a new road.