Abu Rayhan Muhammed ibn Ahmad al-Biruni(973-1048), Persian scholar and scientist, one of the most learned men of his age and an outstanding intellectual figure. Possessing a profound and original mind of encyclopaedic scope, al-Biruni was conversant with Turkish, Persian, Sanskrit, Hebrew, and Syriac in addition to the Arabic in which he wrote. He applied his talents in many fields of knowledge, excelling particularly in astronomy, mathematics, chronology, physics, medicine, and history.(Britannica)
He was also the first Muslim scholar to study India and the Brahminical tradition, and has been described as the father of Indology,the father of geodesy, and "the first anthropologist". Along with Geber and Ibn al-Haytham, al-Biruni was one of the earliest leading exponents of the experimental scientific method. He is responsible for introducing the experimental method into mechanics, and was the first to conduct elaborate experiments related to astronomical phenomena.(Wikipedia)
Al-Biruni's records show that he wrote 113 works, but most of them have been lost.Al-Biruni's important works include Canon, his most comprehensive study of astronomy; Densities, which records specific gravities of various metals, liquids, and gems; Astrolabe, one of the most valuable descriptions of that astronomical instrument; Pharmacology, which contains more than 700 descriptions of drugs; and India, his best-known work, in which he used his knowledge of Sanskrit to describe Indian customs, languages, science, and geography. (Encarta)
Biruni invented the first mechanical geared lunisolar calendar,an early fixed-wired knowledge processing machine with a gear train and gear-wheels,circa 1000 AD. Donald Hill, in his paper(Al-Bīrūnī's mechanical calendar) described this machine according to one of biruni books devoted to the construction of various types of astrolabe and related instruments (Annals of Science Volume 42, Number 2, March 1985).
George Sarton, the father of the history of science, described Biruni as:
"One of the very greatest scientists of Islam, and, all considered, one of the greatest of all times."