History Optional Paper-1 Solution – 2001: Q.5 (d)
Q.5 (d) Write a short essay on: “Sawai Jai Singh, the astronomer”
Raja Sawai Jai belonged to the Kacchawwa dynasty who entered imperial services as a Mansabdar during the reign of Aurangzab and am eminent position under Muhammad Shah.
His contribution towards the development of astronomy in 18th century is remarkable. Jai Singh wrote: “Religion disperses like mist, kingdoms are destroyed, but the work of the scientist remains forever.”
He was the founder of five major observatories (called Jantar Mantar) at Delhi, Jaipur, Ujjain, Mathura and Banaras of which the last three are now extinct.
The observatories consisted of geometric devices for measuring time, predicting eclipses, tracking stars’ location, ascertaining the declinations of planets, and determining the celestial altitudes.
A sundial was very precise which can be used to tell the time to an accuracy of few seconds.
Astronomical Tables (Zij)
As he found the prevalent astronomical tables (Zij) in use at that time defective, he decided to prepare new ones. Therefore he constructed huge instrument in observatory at Delhi. Subsequently, to verify the correctness of his observations, he constructed instruments of the same type in Jaipur, Mathura, Banaras and Ujjain observatories. He produced a set of astronomical tables called Zij-i-Jadid-i- Muhammad Shahi.
Zij-i-jadid-i-Mohammad Shahi‘s first section deals with calendars, the second deals with determination of heavenly bodies and third covers the motions of the Sun, Moon and the rest of the planets, eclipses of the Sun and Moon..
He incorporated in his works latest European astronomical knowledge as is evidenced from the Zij which was based on Latin tables.
He was fluent in Persian and Arabic and was acquainted with Zij-i-Ulugh Beg.
Drawbacks in Jai Singh’s astronomy
(1) A great lacuna was the absence of the use of telescopes till the eighteenth century in India. It made Jai Singh’s observatories outdated because he did not use the telescope for observation. He did send a series of embassies to Portugal, but Portugal itself was out of touch with new developments in astronomy in England and Holland based on observation.
(2) Jai Singh’s observatories were based on the Ptolemic view, repeated by Ulugh Beg, of the world as the centre of the universe, rather on Brahmagupta’s and Copernican view of the sun being the centre.