Book excerpt: This book provides the first presentation of the bilingual textual material that illustrates the transmission of Islamic astronomy to scientists of the Indian Sanskritic tradition. It includes editions of the chapter of the "Tadhkira" in which the mid-thirteenth century Persian astronomer, Nas?r al-d?n al- s? discussed the new solutions that he devised to overcome certain technical problems in the lunar and planetary models of Ptolemaic astronomy and of the learned commentary composed by al-Birjand? in the early sixteenth century together with the Sanskrit translation of both made by Nayanasukha at Jaipur in 1729. An English translation of the Arabic texts and a commentary discussing their technical meanings and the deviations from them in the Sanskrit version together with a glossary of the Arabic and Sanskrit technical vocabulary conclude the volume.