He was to Mahmud of Ghazni what Aristotle was to Alexander, with the difference, however, that he actually accompanied the conqueror on his Indian campaigns. He travelled into different countries and to and from India for the space of forty years, and during that time was much occupied with astronomy and astronomical observations, as well as geography.
His works are said to have exceeded a camel-load, but the most valuable of all of them is his description of India.
It gives an account of the religion of India, its philosophy, literature, geography, chronology, astronomy, customs, law and astrology about a.d. 1030, and has been edited by Edward Sachau, Professor in the Royal University of Berlin.
An English edition, containing a preface, the translation of the Arabic text, notes and indices, has also been published. Al-Beruni died at Ghurna A.D. 1038.
He used to correspond with Avicenna, who was his contemporary, and who gives in his works the answers to the questions addressed to him by this famous geographer, astronomer, geometrician, historian, scholar, and logician.