Rhazes

Rhazes or Rasis , 860-932, Persian physician. He was chief physician at the Baghdad hospital. An observant clinician, he formulated the first known description of smallpox as distinguished from measles in a work known as Liber de pestilentia (tr. A Treatise on Smallpox and Measles, 1848). His works were widely circulated in Arabic, and Greek versions and were published in Latin in the 15th cent. They include a textbook of medicine called Almansor and an encyclopedia of medicine compiled posthumously from his papers and known as Liber continens.

al-Rāzī, Abū Bakr Muḥammad ibn Zakariyyā (850–925 (AH 236–313)). Muslim philosopher, physician, and pre-eminent medical writer; in Europe he became known as Rhazes (Rasis in Chaucer). He wrote a large number of books, including Kitāb al-Mansūrī (tr. into Lat. as Liber Almansoris), Kitāb al-Mulūkī (Liber Regius) and a vast encyclopaedia, completed after his death by his pupils, Hāwī (Continens, first tr. in 1279 and later one of the first books to be printed, five times between 1488 and 1542). He ended his days blind, and refused treatment, saying that he had been in the world so long that he had seen enough of it.