This catalogue of the astronomical manuscripts preserved at the Maharaja Man Singh Museum provides a substantial part of the foundation for an extensive & penetrating analysis of the astronomical activities of Saw Jayasimha Maharaja from 1700 to 1743. Jayasimha collected Sanskrit manuscripts of traditional Indian astronomy, acquired Arabic & Persian manuscripts representative of the Muslim interpretation of Ptolemaic astronomy, built five observatories at which he employed both Hindu & Muslim observers, & produced a set of astronomical tables in Persian based on the Latin tables of Philippe de La Hire.