The Samrat Yantra, constructed by jai singh at jaipur, sometimes called “Supreme Instrument” is an equinoctial sundial of enormous proportion. Not too different from sundials which had been developed hundreds of years earlier, the Samrat Yantra is important because it measures time to a precision that had never before been achieved. The Samrat Yantra at Jaipur, for example, is capable of measuring time to an accuracy of two seconds.
How it works?
The parts of the Samrat Yantra are
1. The gnomon, a triangular wall with its hypotenuse parallel to earth’s axis
2. A pair of quadrants on either side, lying parallel to the plane of the equator.
On a clear day, as the sun passes from east to west, the shadow of the gnomon falls on the scale of the quadrant, indicating local time.
A sundial gives the exact time for its particular locality only, a formula to obtain standard time is used that compensates for the longitude difference between the instrument location and its time zone.
