Introduction to Astronomy, Containing the Eight Divided Books of Abu Ma'shar Abalachus.

Ja'far ibn Muḥammad al-Balkhī (787--886), known as Abū Ma'shar, lived in Baghdad in the 9th century. Originally an Islamic scholar of the hadith (the prophetic traditions of Muhammad) and a contemporary of the famous philosopher al-Kindī, Abū Ma'shar developed an interest in astrology at the relatively late age of 47. He became the most important and prolific writer on astrology in the Middle Ages. His discourses incorporated and expanded upon the studies of earlier scholars of Islamic, Persian, Greek, and Mesopotamian origin. His works were translated into Latin in the 12th century and, through their wide circulation in manuscript form, had a great influence on Western scholars. Kitab al-Mudkhal al-Kabīr (Great introduction) is his most important work and the one most frequently cited by scholars in the West. It contains an astrological theory on the nature of the moon's influence on the tides and was the key work on the subject during the Middle Ages. This edition is the 1140 translation into Latin by Hermann of Carinthia, first printed by Erhard Ratdolt in Augsburg, Germany, in 1489. The woodcut title vignette of a black-faced astronomer reading the stars with an astrolabe and dividers is one of the best-known Renaissance representations of an astronomer.