35. Al.Hassan Al-Murakchi
(660H/1262AD)

Abu Ali al-Hassan Ibn Ali Ibn Umar al-Murrakchi was one of the Moroccan scientists. He lived during the rule of the Almohads in the first half of the 17th century H / middle of the 13th  century AD(214).

He earned fame in astronomy, mathematics, geography and the fabrication of sundials.

Scientific Contributions(215)

He led many researches in trigonometry, introducing a number of innovations. He introduced the co sinus, sinus and tangent. He developed co sinus tables and came up with solutions for some astronomical problems. He provided more details on more than 240 stars for the year 622 H. He was also the first to use lines for equal hours.

In addition, he introduced many important geographical corrections, and put a new map of Morocco

Major Works

-“Jamea al-Mabadi' wal Ghayat fi Ilm al-miqat” (Book of Principles and Goals of Time Measurement). Thanks to this book, al-Murakchi gained a wide reputation among European scientists and was even considered as one of the greatest Muslin and Arab astronomers(216). Hajji Khalifa considered this book as the most interesting work ever compiled in this field and said it is divided into four sciences: mathematics, engines design and utilization, and a section including useful debate to acquire the skill of deduction. The book includes also some issues on algebra and opposition(217). Sarton says, “It is among the best books including precious researches on trigonometry and various sundials.” The book was translated by Emanuel Sidue and published by his son Louis Emily Sidue in 1834-1836. Cara De Faw published the section on astrolabes.

Al-Murrakchi compiled other treatises on mathematics, among which :

- “Kitab al-Kotua al-Makhrutia” (Conical Sections)

-“Rissalat Talkhis al-Amal fi Ruayat al-Hilal”. A treatise on the observation of the moon.