Zij astronomy made its debut in India under the patronage of King Firoz Shah Tughlaq who ruled Delhi from 1351 to 1388. The word “zij” stands for tables of data and these were considered very useful for knowledge about heaven. Arabic and Persian zijes were copied and commented upon in India. Several books on astronomy were written during his reign, and astrolabes — an instrument for measuring the altitude of a star — constructed. On his orders, an astrolabe was placed on the highest minar of his capital, Firozabad (in Delhi). Science writer Owen Gingerich has pointed that there were at Lahore four generations of astrolabe makers whose instrument design remained virtually unchanged for a century and a half. This suggests that these instruments were meant for drawing room decoration rather than actual observations. From the 18th century, we have Raja Sawai Jai Singh’s treatise on instruments, Yantra-prakara, essentially completed before 1724 with some additions made up to 1729. Jai Singh went on to establish a number of (pre-telescopic) masonry observatories. The Delhi Observatory (Jantar Mantar), set up during 1732-24, was followed by a bigger one at his new capital, Jaipur (1728-34). He also built smaller ones at Mathura, Ujjain and Varanasi. The Varanasi Observatory was housed in an already existing building; it is possible that Jai Singh renovated an old observatory.
Jai Singh was not a sovereign ruler. In 1702-03, when a mere lad of 14, he participated in Aurangzeb’s war campaigns against the Marathas and acquitted himself well. Jai Singh came of age at a time when the once mighty Mughal Empire had started losing influence and power. His own rise in the court hierarchy was in direct proportion to the weakening of the central power. For 25 years he served variously as the governor of the provinces of Agra and Malwa, but was dismissed from both the posts in 1737. Jai Singh received huge funds from the emperor for enlisting troops against the Marathas, which he divided between Marathas and himself and preferred to spend his time at his capital. He had dreams of making peace with the Marathas and carving out a vast independent kingdom for himself. He failed in both the missions, but in 1727 he built a new capital, Jaipur, named after himself.
In its heyday, the Mughal Empire was responsible for creation of spectacular buildings (like the Taj Mahal) and gardens. The pastimes of nobility in this period were degeneracy, music and poetry. Jai Singh was an exception. Though not averse to intrigue, he was inspired by the earlier illustrious Mughals rather than his own contemporaries.
Jai Singh’s interest in astronomy was no doubt genuine. But astronomy was also his refuge and probably a political statement too. The year 1720 was a year of rejoicing for Muhammad Shah because he had just freed himself from the clutches of the kingmakers in Delhi. A grand darbar was held on November 25, 1720, where Jai Singh successfully pleaded for the abolition of jazia, a tax imposed on non-Muslims for their protection. It is probably at this darbar that Jai Singh took the royal permission for building his observatory. Incidentally, Jai Singh’s astronomical role model, “the martyr-prince” Ulugh Beg of Samarkand was also a collateral ancestor of the Mughal dynasty. Zij-e-Muhammad Shahi is probably the only genuine tribute Raja Jai Singh ever paid to his ineffectual but charming emperor. Even more ironically from a scientific point of view, the most remarkable feature of Jai Singh’s astronomy is its anachronism. When he came on the scene, the telescope had been in use in Europe for more than 100 years; observatories had been set up at Paris and Greenwich; and many important discoveries made. The telescope was a revolutionary break with the past. Brass and masonry instruments had reached a dead-end even if they were no worse than the earliest telescopic instruments. Jai Singh failed to recognise the significance of European developments. To him European developments were unreliable. However, in his defence it may be argued that vested interests may have played a role in misinforming him about the contemporary trend in Europe.
Jai Singh’s edifice of science did not survive for long. In 1764, the observatory was severely vandalised when Jawahar Singh, son of Suraj Mal, the Jat Raja of Bharatpur, plundered Delhi. Perhaps the most telling commentary on Jai Singh’s dedicated but largely irrelevant scientific enterprise comes from the rather disconcerting fact that his grandson converted the Jaipur Observatory into a gun factory and used his ancestral 400 kg brass astrolabe for target practice.
