(i) In 1725 to calculate the speed of Nakshatras, he built a pure table (Sarani).
(ii) He wrote a scripture on Astrology ‘Jai Singh Karika.
(iii) He built five Vaidhshalas in India to study Astrology. (Jaipur, Delhi, Mathura, Banaras and Ujjain). The observatory of Jaipur (Janta Mantar) is the biggest. In July 2010 it is included in World Heritage site. The old name of Jaipur was Jai Nagar. Sawai Jai Singh made Jaipur, capital of Kachwaha Dynasty in place of Amer. Before the establishment of Jaipur there was a ‘Haudi of Shikar’ which was converted into ‘Badal Mahal’ and construction of Jaipur was started. Sawai Jai Singh was the basic Hindu king who did Rajsuya/Vajpeya/Ashwamedha yogyas. He built Jai Mahal for the living of Yagya Brahmins. He died in Amer on 21 September 1743 A.D. due to blood infection.
