The Astronomical Observatories of Jai Singh c4.s1.22

c4.s1.22

P. de la Hire was a French scholar of repute who lived from A.D. 1640 to 1718. He wrote many mathematical works and in 1702 published his Tabulae Astronomicae of which the first part had appeared in 1687. This work contained, besides the usual tables, a refraction table (which it is said Jai Singh copied) and a description of a machine invented by la Hire to show the theory of eclipses. Another of la Hire's works was 'La Gnomonique ou l'art de tracer des cadrans ou horologes solaires sur toutes sortes de surfaces, par differentes pratiques, avec les démonstrations géometriques de toutes les operations.' This was published in 1682 and would have been useful to Jai Singh.