He was born in Cordoba, al‐Andalus,
(Spain), 979, and he died in Granada, al‐Andalus, on the 29th May 1035, on the
18th of the Rayab month in the Muslim
calendar, at the age of 56.
Ibn al‐Samḥ, known also as
al‐Muhandis (the geometer), was a noted mathematician and astronomer in
Andalusia and an important member of the school of Maslama al‐Majrīṭī ,el
Madrileño, settled in Cordoba. Because of political unrest, Ibn al‐Samḥ fled to
Granada, where he lived (out) for the rest of his life. There he worked in the
service of the local chief, the Berber Ḥabbūs ibn Māksan, whose Jewish
Minister, Samuel ben Nagrella, was also interested in mathematics and
astronomy.
When he moved to Granada with his
family, in this city he opened his own academy, where he explained mathematics
and astronomy. He came to know and study well the books of Ptolemy.
Ibn al‐Samḥ worked in the fields of
astronomy, mathematics, and, possibly, medicine. The 14th‐century historian Ibn
al‐Khaṭīb states that Ibn al‐Samḥ wrote an essay on history, but there is no
other evidence for this assertion. Ibn al‐Nāshī, one of Ibn al‐Samḥ's most
important disciples, gives a list of nine books written by his teacher.
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| Manuscription in the zīj, an astronomical handbook with tables |
In astronomy, Ibn al‐Samḥ, like his
teacher Maslama al‐Majrīṭī, composed a zīj (an astronomical handbook with
tables) based on Khwārizmī's Sindhind, which had been composed in 9th‐century
Baghdad. Ibn al‐Samḥ also composed a treatise on the construction of the
astrolabe and another on its use. Although Ibn al‐Ṣaffār's treatise on the
astrolabe gained more popularity, this long book (129 chapters on the use of
the instrument) is the most complete treatise written in the Iberian Peninsula
during the Middle Ages. The text is especially interesting because it deals with
questions not usually analyzed in works of this kind, such as the visibility of
the Moon and its latitude and longitude. His Kitāb al‐ʿAmal is also important; in it we can find a text that
shows that the school of Maslama knew and used the works of Battānī. The Kitāb al‐ʿAmal was the source of a
treatise on the use of the spherical astrolabe composed at the court of
Alphonse X. Since the king's astronomers did not have an Arabic text on the
spherical astrolabe from which to make the Castilian translation, they took Ibn
al‐Samḥ's treatise and made an adaptation of it. His treatise on the
construction of the equatorium – an instrument originally conceived in Al-Andalus
and later developed in Latin Europe – is another of Ibn al‐Samḥ's major
contributions to astronomy.
Ibn al‐Samḥ is well known for his
many compositions in mathematics. His range of subject matters includes
calculation, numbers, commercial arithmetic, theory of proportions,
arithmetical operations, and the solution of quadratic and cubic equations. His
work in geometry includes a commentary on the book of Euclid, and a general
treatise that includes an important study of straight, curved, and broken
lines.
According to sources that mention him,
Ibn al-Samh was the author of numerous articles and books. At least, there is
reference about ten books that belong to him.
HIS WORKS
1. A commentary on Euclid's work as
an introduction to the geometry (Kitab
al-ila-Madkhal Handasa Uklidus Kitab fi tafsir).
2. Mu'amalat, a book about the nature of the figures (Kitab
al-'adad Timar).
3. A history of physics (Kitab al-'adad Tabi'at).
4.
A book of higher geometry (Kitab
al-kabir fi-l-Handasa).
5. A treatise, in two parts, about
the construction of the astrolabe.
.jpg) |
| Dismantle astrolabe before being built |
6. A second book about the
astrolabe, this time on employment and use. In this work, the manuscript is
preserved in the British Museum.
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| An astrolabe, its parts and the things they are refered to |
7. Some astronomical tables which
were highly praised by the Toledo’s astronomer Azarquiel (Kitab al-Ziy).
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| Toledo's astonomer Azarquiel |
8. A letter about the art of
calculation, there is a copy in El Escorial and another copy in Berlin’s
Library. It is a short treatise of arithmetic. Its content is divided into ten
chapters (Kafiya Risala fi 'ilm al-hisab).
9. A book about the Art of calculation
(Kitab al-kamil fi-l-al-Hawa'i hisab).
10. A book called Book of the planet that was written
around the year 1026 and which Alphonse X ordered to fix and translate under
the title of Book of the instruments of
the sheets of the seven planets. This same work was continued by Azarquiel,
circa 1081.
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| Picture that shows the different phases of the Moon |
SOURCES
Pilar Quirós Iniesta
