I was quite impressed after exploring Jantar Mantar, in Delhi. When I first looked at it, the Jantar Mantar appeared like a gallery of modern art but later I came to know that it is an observatory built by Sawai Jai Singh II of Jaipur during the period 1699-1743. My guide told me that Jai Singh was a keen astronomer and a noble in the Mughal court, was dissatisfied by the errors of brass and metal astronomical instruments. Under patronage from the emperor, he set on himself the task of correcting the existing astronomical tables and updating the almanac with more reliable instruments.

My guide acquainted me with the fact that Delhi's Jantar Mantar was the first of the five observatories that he built with large masonary instruments. The observatory has the Samrat Yantra, a simple equal hour sun dial, the Ram yantra for reading altitudinal angles; Jai Prakash for ascertaining the position of the sun and other celestial bodies, and the Misra Yantra which is a combination of four scientific gadgets.