Jantar Mantar is an astronomical observatory with mason ary instruments, built in 1724 by Jai Singh, the mathematician and astronomer king. The Samrat and Yantra supreme instrument, the largest structure shaped like a right-angled triangle, is actually a huge sun-dial; the other five instruments are intended to show the movements of the sun, moon etc.

At first sight, the Jantar Mantar appears like a gallery of modern art. It is, however, an observatory. Sawai Jia Singh II of Jaipur (1699-1743), 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.

Delhi's Jantar Mantar is the first of the five observatories that he built with large mason ary 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.

A Time-keeper of Celestial Bodies

The various abstract structures within the Jantar Mantar are, in fact, instruments that were used for keeping track of celestial bodies. Yet, Jantar Mantar is not only a timekeeper of celestial bodies, it also tells a lot about the technological achievements under the Rajput kings and their attempt to resolve the mysteries regarding astronomy. The Jantar Mantar of Delhi is only one of the five observatories built by Sawai Jai Singh II, the other four being located at Jaipur, Varanasi, Ujjain and Mathura. All of these were built as far back as AD 1724-1730 during the period generally known as the dark age of Indian history, when the last great Mughal emperor Aurangzeb had died and the Mughal Empire was rapidly declining.

A Renaissance Of Practical Astronomy

Jai Singh's idea was to create a rebirth of practical astronomy among the Indian masses and practicing astronomers. However, the lofty ideals of the Jantar Mantar remained unfulfilled as the country at that time was in chaos and the full potential of this observatory was never realized.

The tale of rejuvenation of Jantar Mantar

Jai Singh tried to use brass instruments in this observatory, but soon gave them up because of several inherent flaws. They were too small, for one thing, their axes were unstable so the center often got displaced. He then decided to follow the style adopted by the renowned Arab astronomer, Prince Ulugh Beg, builder of the famous 15th century observatory at Samarkand, Uzbekistan. The massive masonry instruments at Samarkand suited Jai Singh's architectural tastes and promised to be more accurate because of sheer size. In 1730, Jai Singh sent a mission to the king of Lisbon. On its return to Jaipur, the mission brought back a telescope and the court astronomer by the name of Xavier de Silva. The Observatory This unique observatory was completed in 1724 and remained operational only for seven years.

A Symbol Of Scientific Heritage

The Jantar Mantars may have fallen into disuse but they remain an integral part of India's scientific heritage. It presents that the spirit of scientific enquiry was not dead in India and would have yielded rich results if only an opportunity of research and development had been given to it.

Location: Near Parliament Street, New Delhi.