Banu Musa
Encyclopedia
Persian people
The Persian people are part of the Iranian peoples who speak the modern Persian language and closely akin Iranian dialects and languages. The origin of the ethnic Iranian/Persian peoples are traced to the Ancient Iranian peoples, who were part of the ancient Indo-Iranians and themselves part of...
scholars of Baghdad
Baghdad
Baghdad is the capital of Iraq, as well as the coterminous Baghdad Governorate. The population of Baghdad in 2011 is approximately 7,216,040...
who are known for their Book of Ingenious Devices
Book of Ingenious Devices
The Book of Ingenious Devices was a large illustrated work on mechanical devices, including automata, published in 850 by the three Persian brothers known as the Banu Musa working at the House of Wisdom in Baghdad, Iraq, under the Abbasid Caliphate...
on automata
Automaton
An automaton is a self-operating machine. The word is sometimes used to describe a robot, more specifically an autonomous robot. An alternative spelling, now obsolete, is automation.-Etymology:...
(automatic machine
Machine
A machine manages power to accomplish a task, examples include, a mechanical system, a computing system, an electronic system, and a molecular machine. In common usage, the meaning is that of a device having parts that perform or assist in performing any type of work...
s) and mechanical devices. Another important work of theirs is the Book on the Measurement of Plane and Spherical Figures, a foundational work on geometry
Geometry
Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....
that was frequently quoted by both Islamic and European mathematicians.
The Banu Musa also worked in astronomical observations established in Baghdad by the Abbasid
Abbasid
The Abbasid Caliphate or, more simply, the Abbasids , was the third of the Islamic caliphates. It was ruled by the Abbasid dynasty of caliphs, who built their capital in Baghdad after overthrowing the Umayyad caliphate from all but the al-Andalus region....
Caliph al-Ma'mun
Al-Ma'mun
Abū Jaʿfar Abdullāh al-Māʾmūn ibn Harūn was an Abbasid caliph who reigned from 813 until his death in 833...
. They also participated in an 9th-century expedition to make geodesic
Geodesic
In mathematics, a geodesic is a generalization of the notion of a "straight line" to "curved spaces". In the presence of a Riemannian metric, geodesics are defined to be the shortest path between points in the space...
measurements to determine the length of a degree.
Early life
The Banu Musa were sons of Mūsā ibn Shākir, who had been a highwaymanHighwayman
A highwayman was a thief and brigand who preyed on travellers. This type of outlaw, usually, travelled and robbed by horse, as compared to a footpad who traveled and robbed on foot. Mounted robbers were widely considered to be socially superior to footpads...
and later an astrologer and astronomer to the Caliph al-Maʾmūn. After his death, his young sons were looked after by the court of al-Maʾmūn.
The brothers were given access to the famous House of Wisdom
House of Wisdom
The House of Wisdom was a library and translation institute established in Abbassid-era Baghdad, Iraq. It was a key institution in the Translation Movement and considered to have been a major intellectual centre during the Islamic Golden Age...
library and translation center in Baghdad. They participated in the efforts to translate ancient Greek
Ancient Greece
Ancient Greece is a civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and the Byzantine era. Included in Ancient Greece is the...
works into Arabic by sending for Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
texts from the Byzantines
Byzantine Empire
The Byzantine Empire was the Eastern Roman Empire during the periods of Late Antiquity and the Middle Ages, centred on the capital of Constantinople. Known simply as the Roman Empire or Romania to its inhabitants and neighbours, the Empire was the direct continuation of the Ancient Roman State...
, paying large sums for their translation, and learning Greek themselves. On such trips, Abu Ja'far met and recruited the famous mathematician and translator Thabit ibn Qurra
Thabit ibn Qurra
' was a mathematician, physician, astronomer and translator of the Islamic Golden Age.Ibn Qurra made important discoveries in algebra, geometry and astronomy...
. At some point Hunayn Ibn Ishaq
Hunayn ibn Ishaq
Hunayn ibn Ishaq was a famous and influential Assyrian Nestorian Christian scholar, physician, and scientist, known for his work in translating Greek scientific and medical works into Arabic and Syriac during the heyday of the Islamic Abbasid Caliphate.Ḥunayn ibn Isḥaq was the most productive...
was also part of their team.
Automata
Most notable among their achievements is their work in the field of automationAutomation
Automation is the use of control systems and information technologies to reduce the need for human work in the production of goods and services. In the scope of industrialization, automation is a step beyond mechanization...
, which they utilized in toys and other entertaining creations. They have shown important advances over those of their Greek predecessors. Their Book of Ingenious Devices
Book of Ingenious Devices
The Book of Ingenious Devices was a large illustrated work on mechanical devices, including automata, published in 850 by the three Persian brothers known as the Banu Musa working at the House of Wisdom in Baghdad, Iraq, under the Abbasid Caliphate...
describes 100 such inventions; the ones which have been reconstructed work as designed. While designed primarily for amusement purposes, they employ innovative engineering technologies such as one-way and two-way valves able to open and close by themselves, mechanical memories, devices to respond to feedback, and delays. Most of these devices were operated by water pressure.
Astronomy
- On the Visibility of the Crescent, by Muhammad.
- Book on the Beginning of the World, by Muhammad.
- Book on the Motion of Celestial Spheres (Kitāb Ḥarakāt al‐aflāk), by Muhammad.
- Book of Astronomy (Kitāb al‐Hayʾa), by Muhammad.
- Book on the First Motion of the Celestial Sphere (Kitāb Ḥarakāt al‐falak al‐ūlā), containing a critique of the Ptolemaic system. Muhammad in this book denied the existence of the Ptolemaic 9th sphere which Ptolemy thought was responsible for the motion.
- A book of zijZijZīj is the generic name applied to Islamic astronomical books that tabulate parameters used for astronomical calculations of the positions of the Sun, Moon, stars, and planets. The name is derived from the Middle Persian term zih or zīg, meaning cord...
, by Ahmad
- Another book of zijZijZīj is the generic name applied to Islamic astronomical books that tabulate parameters used for astronomical calculations of the positions of the Sun, Moon, stars, and planets. The name is derived from the Middle Persian term zih or zīg, meaning cord...
, listed under the Banu Musa, mentioned by Ibn YunusIbn YunusIbn Yunus was an important Egyptian Muslim astronomer and mathematician, whose works are noted for being ahead of their time, having been based on meticulous calculations and attention to detail.The crater Ibn Yunus on the Moon is named after...
.
- A translation of a Chinese work called A Book of Degrees on the Nature of Zodiacal Signs.
- Book on The Construction of the Astrolabe, quoted by al-BiruniAl-BiruniAbū al-Rayḥān Muḥammad ibn Aḥmad al-BīrūnīArabic spelling. . The intermediate form Abū Rayḥān al-Bīrūnī is often used in academic literature...
.
- Book on the Solar Year, was traditionally attributed to Thabit ibn QurraThabit ibn Qurra' was a mathematician, physician, astronomer and translator of the Islamic Golden Age.Ibn Qurra made important discoveries in algebra, geometry and astronomy...
, but recent research has shown that it was actually by the Bani Musa.
Mathematics
- Book on the Measurement of Plane and Spherical Figures, later edited by Naṣīr al‐Dīn al‐Ṭūsī in the 13th century. A Latin translation by Gerard of CremonaGerard of CremonaGerard of Cremona was an Italian translator of Arabic scientific works found in the abandoned Arab libraries of Toledo, Spain....
appeared the 12th century under the titles Liber trium fratrum de geometria and Verba filiorum Moysi filii Sekir. This treatise on geometry was used extensively in in the Middle Ages, quoted by authors such as Thābit ibn QurraThabit ibn Qurra' was a mathematician, physician, astronomer and translator of the Islamic Golden Age.Ibn Qurra made important discoveries in algebra, geometry and astronomy...
, Ibn al‐Haytham, Leonardo Fibonacci, Jordanus de Nemore, and Roger BaconRoger BaconRoger Bacon, O.F.M. , also known as Doctor Mirabilis , was an English philosopher and Franciscan friar who placed considerable emphasis on the study of nature through empirical methods...
.
- Book on the Mathematical Proof by Geometry That There Is Not a Ninth Sphere Outside the Sphere of the Fixed Stars, by Ahmad.
- A treatise containing a discussion between Ahmad and Sanad ibn ʿAli.
- Conic Sections of Apollonius of PergaApollonius of PergaApollonius of Perga [Pergaeus] was a Greek geometer and astronomer noted for his writings on conic sections. His innovative methodology and terminology, especially in the field of conics, influenced many later scholars including Ptolemy, Francesco Maurolico, Isaac Newton, and René Descartes...
- Book on a Geometric Proposition Proved by Galen
- Reasoning on the Trisection of an Angle, by Aḥmad,
- Book on an Oblong Round Figure, which contains a description of procedure used to draw an ellipseEllipseIn geometry, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis...
using a string, now called the gardener's construction.
See also
- Their book, Book of Ingenious DevicesBook of Ingenious DevicesThe Book of Ingenious Devices was a large illustrated work on mechanical devices, including automata, published in 850 by the three Persian brothers known as the Banu Musa working at the House of Wisdom in Baghdad, Iraq, under the Abbasid Caliphate...
. - Nuʿaym ibn Muḥammad ibn Mūsā, the son of Abu Ja'far Muhammad, wrote a mathematical treatise.
- Inventions in the Muslim world
- Islamic Golden AgeIslamic Golden AgeDuring the Islamic Golden Age philosophers, scientists and engineers of the Islamic world contributed enormously to technology and culture, both by preserving earlier traditions and by adding their own inventions and innovations...
- Islamic scienceIslamic scienceScience in the medieval Islamic world, also known as Islamic science or Arabic science, is the science developed and practised in the Islamic world during the Islamic Golden Age . During this time, Indian, Iranian and especially Greek knowledge was translated into Arabic...
Further reading
}} Reviews: Seyyed Hossein Nasr (1998) in Isis 89 (1) pp. 112–113; Charles Burnett (1998) in Bulletin of the School of Oriental and African Studies, University of London 61 (2) p. 406.- D El-Dabbah, The geometrical treatise of the ninth-century Baghdad mathematicians Banu Musa (Russian), in History Methodology Natur. Sci., No. V, Math. Izdat. (Moscow, 1966), pp. 131–139.
- Ramon Guardans, A Brief Note on the anwā' Texts of the Late Tenth Century, in: Variantology 4. On Deep Time Relations of Arts, Sciences and Technologies In the Arabic-Islamic World and Beyond, ed. by Siegfried Zielinski and Eckhard Fürlus in cooperation with Daniel Irrgang and Franziska Latell (Cologne: Verlag der Buchhandlung Walther König, 2010), pp. 177–193. http://www.buchhandlung-walther-koenig.de/cat/kwb_45_variantology_4/pid_170000000000790428.aspx
- Claus-Peter Haase, Modest Variations — Theoretical Tradition and Practical Innovation in the Mechanical Arts from Antiquity to the Arab Middle Ages, in: Variantology 4. On Deep Time Relations of Arts, Sciences and Technologies In the Arabic-Islamic World and Beyond, ed. by Siegfried Zielinski and Eckhard Fürlus in cooperation with Daniel Irrgang and Franziska Latell (Cologne: Verlag der Buchhandlung Walther König, 2010), pp. 195–213. http://www.buchhandlung-walther-koenig.de/cat/kwb_45_variantology_4/pid_170000000000790428.aspx