| From: Thomas Hockey et al. (eds.). The Biographical Encyclopedia of Astronomers, Springer Reference. New York: Springer, 2007, pp. 566-567 |
|
Courtesy of 
|
Ibn al‐Ṣaffār: Abū al‐Qāsim Aḥmad
ibn ʿAbd Allāh ibn ʿUmar al‐Ghāfiqī
ibn al‐Ṣaffār al‐Andalusī
Mònica Rius
Born Cordova, al‐Andalus
(Spain)
Died Denia, al‐Andalus
(Spain), 1035
Ibn
al‐Ṣaffār (literally: son of a
coppersmith) was a prominent astronomer at the school of Maslama
al‐Majrīṭī.
Located in Cordova, this was one of the most important centers for the study
of the exact sciences in Andalusia. In Cordova, Ibn al‐Ṣaffār taught arithmetic, geometry,
and astronomy. Among his disciples in Cordova were Ibn Bargūth, al‐Wāsiṭī, Ibn Shahr, al‐Qurashī,
and Ibn al‐ʿAṭṭār. Because of civil war, he moved to Denia, on the Eastern coastline
of the Iberian Peninsula where he lived until his death. His brother, Muḥammad,
who also retired in Denia, was a celebrated astronomical instrument‐maker;
two of his astrolabes and a plate are preserved today in the Royal Scottish
Museum in Edinburgh, the Westdeutsche Bibliothek in Marburg, and the Museo
Nazionale in Palermo.
Ibn
al‐Ṣaffār, along with his teacher
Maslama al‐Majrīṭī, composed works in the
tradition of Khwārizmī's Sindhind;
this is especially significant since Khwārizmī's original text was
lost. Ibn al‐Samḥ and Ibn al‐Ṣaffār also made two recensions. The Arabic text of the version
of Maslama and Ibn al‐Ṣaffār is lost, but there exist
several Latin translations of it: one by Adelard
of Bath; a revision due to Robert of Chester; and another translation
attributed to the Spanish Jew, Petrus Alfonsi (flourished: late 11th/early
12th century). Ibn al‐Samḥ's version has not survived either; only seven chapters
from Ibn al‐Ṣaffār's
canons are still extant. It is difficult to establish which data were taken
from Khwārizmī and which were provided by the Andalusian astronomers,
in as much as materials from the Indo–Iranian, the Greco–Arabic, and the Hispanic
traditions are found. Nevertheless, it seems clear that certain tables that
use the meridian of Cordova or that refer to the Hispanic era are due to Maslama
and his disciples.
Ibn
al‐Ṣaffār's most popular work was
a treatise on the uses of the astrolabe, a book that was still being used
in Europe during the 15th century. According to Ṣāʿid al‐Andalusī, the treatise was written
in a clear, simple, and comprehensible style. King Alfonso
X's astronomers often used the work. Johannes Hispalensis and Plato
of Tivoli (flourished: 1134–1145) translated it into Latin. Johannes Hispalensis'
translation (edited by Millás in 1955) misattributed the translation of Ibn
al‐Ṣaffār's treatise on the astrolabe
to Maslama. This may be explained since the last chapter in the treatise is
probably a fragment taken from Maslama's zīj, which led later
scholars to attribute the entire work to the teacher Maslama rather than to
the student Ibn al‐Ṣaffār. The translation by Plato
of Tivoli (edited by Lorch et al., 1994) contains an introduction
in which Plato dedicates his work to a certain Johannes David and states that
this is the best Arabic treatise that he has ever read. There also exists
a Hebrew version by Profeit Tibbon (Jacob
ben Makhir) as well as one in Old Spanish and Spanish with Hebrew
characters. The Arabic text was edited by J. Millás Vallicrosa (who also translated
it into Catalan) in 1955.
One of the topics Ibn al‐Ṣaffār analyzed was the determination of the qibla (direction
toward Mecca); the text gives a value of 30° south of east for the samt
of the qibla at Cordova, which corresponds to the azimuth of the rising
Sun at the winter solstice. Ibn al‐Ṣaffār also refers to Ptolemy's
Geography, which indicates that Andalusian astronomers were interested
in other works apart from the Sindhind.
Ibn
al‐Ṣaffār is credited with
being the author of the inscriptions on the oldest surviving Islamic sundial,
made circa 1000, in Cordova (and preserved in the Museo Arqueológico
Provincial of Cordova, Spain). On a fragment of the sundial it is possible
to observe the curve for the midday (ẓuhr) prayer; presumably the
original instrument had that of the afternoon (ʿaṣr) prayer. Errors on the
sundial, however, could not have been made by a careful astronomer, so the
instrument may not have been constructed by Ibn al‐Ṣaffār himself, but perhaps
was “in the manner of” Ibn al‐Ṣaffār.
Selected References
Castells,
Margarita and Julio Samsó (1995). “Seven Chapters of Ibn al‐Ṣaffār's Lost Zīj.”
Archives internationales d'histoire des sciences 45: 229–262.
Goldstein,
Bernard R. (1971). “Ibn al‐Ṣaffār.” In Encyclopaedia
of Islam. 2nd ed. Vol. 3, p. 924. Leiden: E.
J. Brill.
King, David A. (1996). “Astronomy
and Islamic Society: Qibla, Gnomonics
and Timekeeping.” In Encyclopedia of the
History of Arabic Science, edited by Roshdi
Rashed, Vol. 1, pp. 128–184. London:
Routledge. (See esp. pp. 163–164.)
Lorch, Richard
(1999). “The Treatise on the Astrolabe by Rudolf of Bruges.” In Between
Demonstration and Imagination: Essays in the History of Science and Philosophy
Presented to John D. North, edited by Lodi Nauta
and Arjo Vanderjagt, pp.
55–100. Leiden: Brill. (See pp.
56–57, 59, 87.)
Lorch,
Richard, Gerhard Brey, Stefan Kirschner, and Christoph Schöner (1994). “Ibn as‐Ṣaffār's
Traktat über das Astrolab in der Übersetzung von Plato von Tivoli.” In Cosmographica et Geographica:
Festschrift für Heribert
M. Nobis zum 70. Geburstag, edited by Bernhard Fritscher
and Gerhard Brey. Vol. 1, pp. 125–180. Algorismus,
Vol. 13. Munich.
Millás Vallicrosa,
José María (1940). “Un nuevo tratado de astrolabio, de R. Abraham b. ʿEzra.” Al‐Andalus 5: 1–29.
——— (1942).
Las traducciones orientales en los manuscritos de la Biblioteca de la Catedral
de Toledo. Madrid, pp. 261–284. (Edition
of Ibn al‐Ṣaffār's
treatise on the use of the astrolabe in Johannes Hispalensis's
translation.)
——— (1944).
“Sobre un ‘Tratado de astrolabio' atribuido a Abraham b. ʿEzra.” Sefarad 4: 31–38.
——— (1947).
El libro de los fundamentos de las Tablas astronómicas. Madrid,
pp. 50–51.
——— (1955).
“Los primeros tratados de astrolabio en la España árabe.” Revista del Instituto Egipcio
de Estudios Islámicos (Madrid)
3: 35–49 (for study in Spanish); 47–76 (for edition of Ibn al‐Ṣaffār's
text in Arabic).
Rosenfeld, B. A.
and Ekmeleddin Ihsanoğlu
(2003).
Mathematicians, Astronomers, and Other Scholars of Islamic Civilization
and Their Works (7th–19th c.). Istanbul: Research Center for Islamic History,
Art and Culture (IRCICA), pp. 121–122.
Sāʿid
al‐Andalusī (1912). Kitāb Tabaqāt
al‐umam, edited by P. Louis Cheikho. Beirut: Imprimerie
Catholique, p. 70. (French translation with notes by Régis Blachère as Livre
des catégories des nations. Paris: Larose, 1935,
pp. 130–131.)
Samsó, Julio
(1992). Las ciencias de los antiguos en al‐Andalus. Madrid:
Mapfre, pp. 85, 87, 92, 96, 98, 102, 125, 133, 251,
314.
Sezgin, Fuat (1978). Geschichte des arabischen
Schrifttums. Vol. 6, Astronomie, pp. 250–251. Leiden: E. J. Brill.
Suter, Heinrich
(1900). “Die Mathematiker und Astronomen der Araber und ihre Werke.” Abhandlungen
zur Geschichte der mathematischen
Wissenschaften, p. 86 num. 196; and Suter, “Nachträge und Berichtigungen.” Abhandlungen
zur Geschichte der mathematischen
Wissenschaften, p. 169.
Vernet,
Juan and Julio Samsó (1996). “The
Development of Arabic Science in Andalusia.” In Encyclopedia
of the History of Arabic Science, edited by Roshdi
Rashed, Vol. 1, pp. 243–275.
London: Routledge. (See esp. pp.
252, 254, 256.)