The Astronomical Observatories of Jai Singh c12.13

c12.13

The Digamśa Yantra is similar to the one at Benares. It is situated quite close to the Samrāṭ Yantra on the east side and consists of an outer circular wall, 36 feet 10 inches in diameter and 8 feet 10 inches high. Concentric with this is another wall, 24 feet 4 inches in diameter and 4 feet 6 inches high. Originally there was a pillar at the centre, but it has been removed. Cross wires were stretched north to south and east to west on the outer wall. At the four points of the compass, in the outer and inner walls, were arched openings, but all of those in the outer wall, except that to the west, have been filled up. The outer walls are badly cracked, and a great part of the foundations is now exposed. This is due to the bad drainage of the slope to the river. The nullah that passes close by the Digamśa Yantra could easily be diverted. In Hunter's time the building was "roofed with tiles and converted into the abode of a Hindu deity," so that Hunter was unable to examine its construction. This is of interest, as showing that, even in the eighteenth century, the instrument was no longer used for astronomical purposes. Hunter also writes¹:—"Urania fled before the brazen fronted Mars, and the observatory was converted into an arsenal and foundry of cannon."