The Astronomical Observatories of Jai Singh c13.15

c13.15

The Digamśa Yantra (‘Azimuth instrument’), marked DD in the plan, is the large circular building at the east of the terrace. It is partly visible in the general view of the Mānmandira (figure 64). The exterior diameter is 31¼ feet, the outer wall is 8 feet 4 inches high and the inner wall and central pillar are each 4 feet 2 inches high, and an iron rod fixed to the central pillar is of the same height as the outer wall. The tops of both walls were originally graduated into degrees, etc.; and cross wires were stretched north to south and east to west on the outer wall. The use of the instrument is to measure azimuths