Jantar Mantar: The Observatory of Sawai Jai Singh II

A bird's eye view of Jantar Mantar

Jantar Mantar is one of the most unique sights on the planet. The brainchild of Sawai Jai Singh II (ruler of Jaipur from 1699-1743), no account of Jantar Mantar is complete without a thumbnail sketch of this remarkable man. Responsible for the design and execution of the city of Jaipur, Sawai Jai Singh was earmarked for greatness almost from birth.  The title "Sawai" means "one and a quarter," indicating intelligence and abilities superior to normal men. It was bestowed upon Jai Singh as a child by the Mughul emperor Aurangzeb, in recognition of the boy's quick wit. He certainly lived up to the name, and Jantar Mantar is an excellent example of Sawai Jai Singh II's genius. It is one of five such observatories constructed by him; another large one is found in Delhi, and supplementary observatories were built in Varanasi, Ujjain, and Maratha. The purpose of these observatories was to precisely fix the astrological dates that governed the life of the Hindu people, who consulted the stars before undertaking any great event. In addition to being a great ruler and warrior, Sawai Jai Singh II was a learned astronomer who not only had the great European and Indian astronomical tracts translated, but who was sufficiently knowledgeable in the area to note discrepancies and inadequacies in the texts and tables and to correct them.

The basic premise behind Jantar Mantar is simple but ingenious. First, one way to reduce the inaccuracy of the instruments was to make them as large as humanly possible, while another way was to make instruments without moving parts, cutting down on a second source of errors. Finally, the observatory consists of a whole series of instruments which are interrelated, so that each may help calibrate and measure the accuracy of the others. In this manner, the measurements of the heavens do not remain dependent upon one primary instrument, from which all the rest take their bearings. It is a system designed to produce accurate measurements of the celestial spheres and their movement. Much has been made of the fact that Sawai Jai Singh II did not subscribe to the Copernican theory, continuing to believe that the sun revolved around the earth. The implication, of course, is that for all his sophistication, the ruler of Jaipur remained, at heart, a rather unenlightened soul. However, before arriving at such a judgment, critics would do well to consider the reason that Sawai Jai Singh II constructed this observatory. It was not to engage in the abstract science of astronomy, as it was practiced in the west, nor was it to pioneer advances in the field (although he certainly did succeed in doing so); rather, it was to more accurately gain the information needed for conducting the affairs of state, affairs of the heart. It was further used to ascertain when the monsoons would come and when the crops may be planted. Jantar Mantar was designed to be the handmaiden, not of science, but of Hindu Cosmology.

A Virtual Tour of Jantar Mantar

Instructions: There are two ways to use this tour. You may place the mouse over the numbers in the illustration below, and the respective description page will open [note: this requires that adblock is turned off for this site]. If that does not work, please select the appropriately numbered box the table below and click on the link to open the page.

1. Great Samrat Yantra

5. Great Rama Yantra 9. Narivalaya Yantra 13. Unnatansha Yantra
2. Shasthansa Yantra
6. Digasama Yantra 10. Laghu Samrat Yantra 14. Dakshino Bhitti Yantra
3. Rashivalaya Yantra 7. Chakra Yantra 11. Kranti Writa Yantra 15. Jai Singh's Seat
4. Small Rama Yantra 8. Jai Prakash Yantra 12. Raj Yantra


Return to Jaipur Main Page