Jantar Mantar
Sawai Jai Singh's masonry observatory — instruments built at building scale to beat the errors of brass.
Maharaja Sawai Jai Singh II of Amber was asked by the Mughal emperor to correct the astronomical tables then in use. His answer was to abandon small brass instruments altogether: their graduations were too coarse and their bearings wore. Instead he built the instruments as architecture, in plastered masonry, on the theory that a larger radius yields a finer reading.
The result is a walled compound of shapes that look like abstract sculpture and are in fact calculating machines. The Samrat Yantra is a giant sundial whose gnomon is a staircase; the hemispherical Jai Prakash bowls map the sky onto the ground so an observer can stand inside the celestial sphere; the Misra Yantra combines several functions and can indicate noon in cities far outside India. Four more of Jai Singh's observatories survive elsewhere, but this was the first, and it sits improbably in the middle of modern Connaught Place.
- 01Samrat YantraThe Supreme Instrument — a sundial accurate, in principle, to a couple of seconds.
- 02Jai Prakash YantraTwo sunken marble bowls, each a hollow map of the heavens with the observer inside it.
- 03Misra YantraA composite of five instruments, including one that marks noon in Zurich and Notting Hill.
Small and quickly walked, but the geometry only clicks in bright sun when the shadows are sharp. Ten minutes from Connaught Place on foot.