Geography and cartography in medieval Islam
Medieval Islamic geography was based on Hellenistic geography and reached its apex with Muhammad al-Idrisi in the 12th century. After its beginnings in the 8th century based on Hellenistic geography, Islamic geography was patronized by the Abbasid caliphs of Baghdad. Various Islamic scholars contributed to its development, the most notable include Al-Khwārizmī, Abū Zayd al-Balkhī, Abu Rayhan Biruni. Islamic cartographers inherited Geography in the 9th century; these were not slavishly followed. Instead and Persian cartography followed Al-Khwārizmī in adopting a rectangular projection, shifting Ptolemy's Prime Meridian several degrees eastward, modifying many of Ptolemy's geographical coordinates. Having received Greek writings directly and without Latin intermediation and Persian geographers made no use of European-style T-O maps. In the 11th century, the Karakhanid Turkic scholar Mahmud al-Kashgari was the first to draw a unique Islamic world map, where he illuminated the cities and places of the Turkic peoples of Central and Inner Asia.
He showed the lake Issyk-Kul as the center of the world. The earliest reference to a compass in the Muslim world occurs in a Persian talebook from 1232, where a compass is used for navigation during a trip in the Red Sea or the Persian Gulf; the fish-shaped iron leaf described indicates that this early Chinese design has spread outside of China. The earliest Arabic reference to a compass, in the form of magnetic needle in a bowl of water, comes from a work by Baylak al-Qibjāqī, written in 1282 while in Cairo. Al-Qibjāqī described a needle-and-bowl compass used for navigation on a voyage he took from Syria to Alexandria in 1242. Since the author describes having witnessed the use of a compass on a ship trip some forty years earlier, some scholars are inclined to antedate its first appearance in the Arab world accordingly. Al-Qibjāqī reports that sailors in the Indian Ocean used iron fish instead of needles. Late in the 13th century, the Yemeni Sultan and astronomer al-Malik al-Ashraf described the use of the compass as a "Qibla indicator" to find the direction to Mecca.
In a treatise about astrolabes and sundials, al-Ashraf includes several paragraphs on the construction of a compass bowl. He uses the compass to determine the north point, the meridian, the Qibla; this is the first mention of a compass in a medieval Islamic scientific text and its earliest known use as a Qibla indicator, although al-Ashraf did not claim to be the first to use it for this purpose. In 1300, an Arabic treatise written by the Egyptian astronomer and muezzin Ibn Simʿūn describes a dry compass used for determining qibla. Like Peregrinus' compass, Ibn Simʿūn's compass did not feature a compass card. In the 14th century, the Syrian astronomer and timekeeper Ibn al-Shatir invented a timekeeping device incorporating both a universal sundial and a magnetic compass, he invented it for the purpose of finding the times of prayers. Arab navigators introduced the 32-point compass rose during this time. In 1399, an Egyptian reports two different kinds of magnetic compass. One instrument is a “fish” made of willow wood or pumpkin, into which a magnetic needle is inserted and sealed with tar or wax to prevent the penetration of water.
The other instrument is a dry compass. In the 15th century, the description given by Ibn Majid while aligning the compass with the pole star indicates that he was aware of magnetic declination. An explicit value for the declination is given by ʿIzz al-Dīn al-Wafāʾī. Pre modern Arabic sources refer to the compass using the term ṭāsa for the floating compass, or ālat al-qiblah for a device used for orienting towards Mecca. Friedrich Hirth suggested that Arab and Persian traders, who learned about the polarity of the magnetic needle from the Chinese, applied the compass for navigation before the Chinese did. However, Needham described this theory as "erroneous" and "it originates because of a mistraslation" of the term chia-ling found in Zhu Yu's book Pingchow Table Talks. History of geography History of cartography Bibliography "How Greek Science Passed to the Arabs" by De Lacy O'Leary Islamic Geography in the Middle Ages
Ma Huan, courtesy name Zongdao, pen name Mountain-woodcutter, was a Chinese voyager and translator who accompanied Admiral Zheng He on three of his seven expeditions to the Western Oceans. Ma was a Muslim and was born in Zhejiang's Kuaiji Commandery, an area within the modern borders of Shaoxing, he knew several Classical Buddhist texts. He learned Arabic to be able to translate. In the 1413 expedition, he visited Champa, Sumatra, Siam and Hormuz. In the 1421 expedition, he visited Malacca, Sumatra, Ceylon, Calicut and Hormuz. In the 1431 expedition, he visited Bengal, Sonargaon and Calicut. From Calicut, he was sent by Eununch Hong Bao as emissary to Mecca. During his expeditions, Ma Huan took notes about the geography, weather conditions, economy, local customs method of punishment for criminals. Returned home on his first expedition, he began writing a book about his expedition, the first draft of, ready around 1416, he expanded and modified his draft during expeditions, the final version was ready around 1451.
The title of his book was Yingya Shenglan. During the Ming dynasty and Qing dynasty, there were many handcopied editions; the latest authentic text of a printed version was annotated by historian Feng Chengjun. A newer edition, based on Ming dynasty handcopied editions, was published by Ocean Publishing House in China. An annotated English translation by J. V. G. Mills was published by the Hakluyt Society in 1970, reprinted in 1997 by The White Lotus Press in Bangkok. Mills's translation was based on the edition by Feng Cheng jun; the Yingya Shenglan is considered by sinologists worldwide as a primary source for the history of Ming dynasty naval exploration, history of South East Asia and history of India. Some scholars who have done research work on Ma Huan are J. J. L. Duyvendak, F. Hirth, Paul Pelliot, Feng Chengjun, Xiang Da, J. V. G. Mills. Fei Xin, another participants of Zheng He's expeditions who wrote a book The "Mao Kun map" in Wubei Zhi Ying-yai Sheng-lan, The Overall Survey of the Ocean's Shores 1433 by Ma Huan, translated by J.
V. G. Mills, with foreword and preface, Hakluty Society, London 1970; when Asia was the World: Traveling Merchants, Scholars and Monks who created the "Riches of the East" Da Capo Press, Perseus Books, 2008. ISBN 0-306-81556-7. J. V. G. Mills. Ma Huan: Ying-yai sheng-lan ‘The overall survey of the ocean's shores’, translated from the Chinese text edited by Feng Ch'eng-chün. Cambridge University Press
Granada is the capital city of the province of Granada, in the autonomous community of Andalusia, Spain. Granada is located at the foot of the Sierra Nevada mountains, at the confluence of four rivers, the Darro, the Genil, the Monachil and the Beiro, it sits at an average elevation of 738 m above sea level, yet is only one hour by car from the Mediterranean coast, the Costa Tropical. Nearby is the Sierra Nevada Ski Station, where the FIS Alpine World Ski Championships 1996 were held. In the 2005 national census, the population of the city of Granada proper was 236,982, the population of the entire urban area was estimated to be 472,638, ranking as the 13th-largest urban area of Spain. About 3.3% of the population did not hold Spanish citizenship, the largest number of these people coming from South America. Its nearest airport is Federico García Lorca Granada-Jaén Airport; the Alhambra, an Arab citadel and palace, is located in Granada. It is the most renowned building of the Islamic historical legacy with its many cultural attractions that make Granada a popular destination among the tourist cities of Spain.
The Almohad influence on architecture is preserved in the Granada neighborhood called the Albaicín with its fine examples of Moorish and Morisco construction. Granada is well-known within Spain for the University of Granada which has an estimated 82,000 students spread over five different campuses in the city; the pomegranate is the heraldic device of Granada. The region surrounding what today is Granada has been populated since at least 5500 BC and experienced Roman and Visigothic influences; the most ancient ruins found in the city belong to an Iberian oppidum called Ilturir, in the region known as Bastetania. This oppidum changed its name to Iliberri, after the Roman conquest of Iberia, to Municipium Florentinum Iliberitanum; the Umayyad conquest of Hispania, starting in AD 711, brought large parts of the Iberian Peninsula under Moorish control and established al-Andalus. Granada's historical name in the Arabic language was غرناطة; the word Gárnata means "hill of strangers". Because the city was situated on a low plain and, as a result, difficult to protect from attacks, the ruler decided to transfer his residence to the higher situated area of Gárnata.
In a short time this town was transformed into one of the most important cities of al-Andalus. In the early 11th century, after the collapse of the Umayyad Caliphate, the Berber Zawi ben Ziri established an independent kingdom for himself, the Taifa of Granada, his surviving memoirs — the only ones for the Spanish "Middle Ages" — provide considerable detail for this brief period. The Zirid Taifa of Granada was a Jewish state in all but name, it is the only time between Biblical times and the twentieth century that a Jewish ruler commanded an army. It was the center of Jewish culture and scholarship. Early Arabic writers called it "Garnata al-Yahud".... Granada was in the eleventh century the center of Sephardic civilization at its peak, from 1027 until 1066 Granada was a powerful Jewish state. Jews did not hold the foreigner status typical of Islamic rule. Samuel ibn Nagrilla, recognized by Sephardic Jews everywhere as the quasi-political ha-Nagid, was king in all but name; as vizier he made policy and—much more unusual—led the army....
It is said that Samuel’s strengthening and fortification of Granada was what permitted it to survive as the last Islamic state in the Iberian peninsula. All of the greatest figures of eleventh-century Hispano-Jewish culture are associated with Granada. Moses Ibn Ezra was from Granada. Ibn Gabirol’s patrons and hosts were the Jewish viziers of Granada, Samuel ha-Nagid and his son Joseph; when Joseph took over after his father's death, he proved to lack his father's diplomacy, bringing on the 1066 Granada massacre, which ended the Golden Age of Jewish Culture in Spain. By the end of the 11th century, the city had spread across the Darro to reach the hill of the future Alhambra, included the Albaicín neighborhood; the Almoravids ruled Granada from 1090 and the Almohad dynasty from 1166. In 1228, with the departure of the Almohad prince Idris al-Ma'mun, who left Iberia to take the Almohad leadership, the ambitious Ibn al-Ahmar established the last and longest reigning Muslim dynasty in the Iberian peninsula, the Nasrids.
With the Reconquista in full swing after the conquest of Córdoba in 1236, the Nasrids aligned themselves with Fernando III of Castile becoming the Emirate of Granada in 1238. According to some historians, Granada was a tributary state to the Kingdom of Castile since that year, it provided connections with Muslim and Arab trade centers for gold from sub-Saharan Africa and the Maghreb, exported silk and dried fruits produced in the area. The Nasrids supplied troops from the Emirate and mercenaries from North Africa for service to Castile. Ibn Battuta, a famous traveller and an authentic historian, visited the Kingdom of Granada in 1350, he described it as a powerful and self-sufficient kingdom in its own right, although embroiled in skirmishes with the Kingdom of Castile. In his journal, Ibn Battuta called Granada the “metropolis of Andalusia and the bride of its cities.”During the Moor rule, Granada was a city with adherents to many religions and ethnicities who lived in separate quarters. During this Nasrid period there were 137 Muslim mosques in the Medina of Granada.
On January 2, 1492, the last Muslim ruler in Iberia
Ala-al-din abu Al-Hassan Ali ibn Abi-Hazm al-Qarshi al-Dimashqi, known as Ibn al-Nafis, was an Arab physician from Damascus famous for being the first to describe the pulmonary circulation of the blood. The work of Ibn al-Nafis regarding the right sided circulation pre-dates the work of William Harvey's De motu cordis. Both theories attempt to explain circulation; as an early anatomist, Ibn al-Nafis performed several human dissections during the course of his work, making several important discoveries in the fields of physiology and anatomy. Besides his famous discovery of the pulmonary circulation, he gave an early insight of the coronary and capillary circulations, a contribution for which he is sometimes described as "the father of circulatory physiology". Apart from medicine, Ibn al-Nafis studied jurisprudence and theology, he was an expert on the Shafi'i school of an expert physician. The number of medical textbooks written by Ibn al-Nafis is estimated at more than 110 volumes. Ibn al-Nafis was born in 1213 to an Arab family at a village near Damascus named Karashia, after which his Nisba might be derived.
Early in his life, He studied theology and literature. At the age of 16, he started studying medicine for more than ten years at the Nuri Hospital in Damascus, founded by the Turkish Prince Nur-al Din Muhmud ibn Zanki, in the 12th century, he was contemporary with the famous Damascene physician Ibn Abi Usaibia and they both were taught by the founder of a medical school in Damascus, Al-Dakhwar. Ibn Abi Usaibia does not mention Ibn al-Nafis at all in his biographical dictionary "Lives of the Physicians"; the intentional omission could be due to personal animosity or maybe rivalry between the two physicians. In 1236, Ibn al-Nafis, along with some of his colleagues, moved to Egypt under the request of the Ayyubid sultan al-Kamil. Ibn al-Nafis was appointed as the chief physician at al-Naseri hospital, founded by Saladin, where he taught and practiced medicine for several years. One of his most notable students was the famous Christian physician Ibn al-Quff. Ibn al-Nafis taught jurisprudence at al-Masruriyya Madrassa.
His name is found among those of other scholars, which gives insight into how well he was regarded in the study and practice of religious law. Ibn al-Nafis lived most of his life in Egypt, witnessed several pivotal events like the fall of Baghdad and the rise of Mamluks, he became the personal physician of the sultan Baibars and other prominent political leaders, thus showcasing himself as an authority among practitioners of medicine. In his life, when he was 74 old, Ibn al-Nafis was appointed as the chief physician of the newly founded al-Mansori hospital where he worked until the rest of his life. Ibn al-Nafis died in Cairo after some days sickness, his student Safi Aboo al-fat'h composed a poem about him. Prior to his death, he donated his house and library to Qalawun Hospital or, as it was known, the House of Recovery; the most voluminous of his books is Al-Shamil fi al-Tibb, planned to be an encyclopedia comprising 300 volumes. However, Ibn al-Nafis managed to publish only 80 before his death, the work was left incomplete.
Despite this fact, the work is considered one of the largest medical encyclopedias written by one person, it gave a complete summary of the medical knowledge in the Islamic world at the time. Ibn al-Nafis bequeathed his encyclopedia along with all of his library to the Mansoory hospital where he had worked before his death. Along the time, much of the encyclopedia volumes got lost or dispersed all over the world with only 2 volumes still being extant in Egypt; the Egyptian scholar Youssef Ziedan started a project of collecting and examining the extant manuscripts of this work that are cataloged in many libraries around the world, including the Cambridge University Library, the Bodleian Library, the Lane Medical Library at Stanford University. Sharh Tashrih al-Qanun, published when Ibn al-Nafis was only 29 years old, still it is regarded by many as his most famous work. While it did not prove to be as popular as his medical encyclopedia in the Islamic circles, the book is of great interest today specially for science historians who are concerned with its celebrated discovery of the pulmonary circulation.
The book discusses the anatomical concepts of Avicenna's Canon. It starts with a preface in which Ibn al-Nafis talks about the importance of the anatomical knowledge for the physician, the vital relationship between anatomy and physiology, he proceeds to discuss the anatomy of the body which he divides into two types. What distinguish the book most is the confident language which Ibn al-Nafis shows throughout the text and his boldness to challenge the most established medical authorities of the time like Galen and Avicenna. Ibn al-Nafis, was one of the few medieval physicians-if not the only one-who contributed noticeably to the science of physiology and tried to push it beyond the hatch of the Greco-Roman tradition; the particular manuscript of Ibn al-Nafis' commentary on Hippocrates' Nature of Man is preserved by the National Library of Medicine. It is unique and significant because it is the only recorded copy that contains the commentary from Ibn al-Nafïs on the Hippocratic treatise on the Nature of Man.
Al-Nafïs's commentary on the Nature o
Derviş Mehmed Zillî, known as Evliya Çelebi, was an Ottoman explorer who travelled through the territory of the Ottoman Empire and neighboring lands over a period of forty years, recording his commentary in a travelogue called the Seyahatname. The name Çelebi is an honorific title meaning gentleman. Evliya Çelebi was born in Constantinople in 1611 to a wealthy family from Kütahya. Both his parents were attached to the Ottoman court, his father, Derviş Mehmed Zilli, as a jeweller, his mother as an Abkhazian relation of the grand vizier Melek Ahmed Pasha. In his book, Evliya Çelebi traces his paternal genealogy back to Khoja Akhmet Yassawi, an early Sufi mystic. Evliya Çelebi received a court education from the Imperial ulama, he may have joined the Gulshani Sufi order, as he shows an intimate knowledge of their khanqah in Cairo, a graffito exists in which he referred to himself as Evliya-yı Gülşenî. A devout Muslim opposed to fanaticism, Evliya could recite the Quran from memory and joked about Islam.
Though employed as clergy and entertainer to the Ottoman grandees, Evliya refused employment that would keep him from travelling. His journal writing began in Constantinople, taking notes on buildings, markets and culture, in 1640 it was extended with accounts of his travels beyond the confines of the city; the collected notes of his travels form. He fought the House of Habsburg in Principality of Transylvania. Evliya Çelebi died in 1684, it is unclear whether he was in Cairo at the time. Evliya Çelebi visited the town of Mostar in Ottoman Bosnia and Herzegovina, he wrote that the name Mostar means "bridge-keeper", in reference to the town's celebrated bridge, 28 meters long and 20 meters high. Çelebi wrote that it "is like a rainbow arch soaring up to the skies, extending from one cliff to the other.... I, a poor and miserable slave of Allah, have passed through 16 countries, but I have never seen such a high bridge, it is thrown from rock to rock as high as the sky." In 1660 Çelebi went to Kosovo and referred to the central part of the region as Arnavud and noted that in Vučitrn its inhabitants were speakers of Albanian or Turkish and few spoke "Boşnakca".
The highlands around the Tetovo, Peć and Prizren areas Çelebi considered as being the "mountains of Arnavudluk". Çelebi referred to the "mountains of Peć" as being in Arnavudluk and considered the Ibar river that converged in Mitrovica as forming Kosovo's border with Bosnia. He viewed the "Kılab" or Lab river as having its source in Arnavudluk and by extension the Sitnica as being part of that river. Çelebi included the central mountains of Kosovo within Arnavudluk. Çelebi claimed to have encountered Native Americans as a guest in Rotterdam during his visit of 1663. He wrote: " cursed those priests, saying,'Our world used to be peaceful, but it has been filled by greedy people, who make war every year and shorten our lives.'"While visiting Vienna in 1665–66, Çelebi noted some similarities between words in German and Persian, an early observation of the relationship between what would be known as two Indo-European languages. Çelebi visited Crete and in book II describes the fall of Chania to the Sultan.
Of oil merchants in Baku Çelebi wrote: "By Allah's decree oil bubbles up out of the ground, but in the manner of hot springs, pools of water are formed with oil congealed on the surface like cream. Merchants wade into these pools and collect the oil in ladles and fill goatskins with it, these oil merchants sell them in different regions. Revenues from this oil trade are delivered annually directly to the Safavid Shah." Evliya Çelebi remarked on the impact of Cossack raids from Azak upon the territories of the Crimean Khanate, destroying trade routes and depopulating the regions. By the time of Çelebi's arrival, many of the towns visited were affected by the Cossacks, the only place he reported as safe was the Ottoman fortress at Arabat.Çelebi wrote of the slave trade in the Crimea: A man who had not seen this market, had not seen anything in this world. A mother is severed from her son and daughter there, a son—from his father and brother, they are sold amongst lamentations, cries of help and sorrow.
In 1667 Çelebi expressed his marvel at the Parthenon's sculptures and described the building as "like some impregnable fortress not made by human agency." He composed a poetic supplication that the Parthenon, as "a work less of human hands than of Heaven itself, should remain standing for all time." In contrast to many European and some Jewish travelogues of Syria and Palestine in the 17th century, Çelebi wrote one of the few detailed travelogues from an Islamic point of view. Çelebi visited Palestine twice, once in 1649 and once in 1670–1. An English translation of the first part, with some passages from the second, was published in 1935–1940 by the self-taught Palestinian scholar Stephan Hanna Stephan who worked for the Palestine Department of Antiquities. Although many of the descriptions the Seyâhatnâme were written in an exaggerated manner or were plainly inventive fiction or third-source misinterpretation, his notes remain a useful guide to the culture and lifestyles of the 17th century Ottoman Empire.
The first volume deals with Constantinople, the final volume with Egypt. There is no English translation of the entire Seyahatname, although there are translations of various parts; the longest single English translation was published in 1834 by Joseph von Hammer-Purgstall, an Austrian orientalist: it may be found unde
Ahmad ibn Fadlan
Ibn Fadlan was a 10th-century Arab Muslim traveler, famous for his account of his travels as a member of an embassy of the Abbasid Caliph of Baghdad to the king of the Volga Bulgars, known as his Risala. His account is most notable for providing a detailed description of the Volga Vikings, including an eyewitness account of a ship burial. Ahmad ibn Fadlan was described as an Arab in contemporaneous sources. However, the Encyclopedia of Islam and Richard N. Frye add that nothing can be said with certainty about his origin, his ethnicity, his education, or the dates of his birth and death. Primary sources documents and historical texts reveal that Ahmad Ibn Fadlan was a “faqih”, an expert in Islamic jurisprudence and faith, in the court of the Abbasid Caliph Al-Muqtadir, it appears certain from his writing that prior to his departure on his historic mission, he had been serving for some time in the court of al-Muqtadir. Other than the fact that he was both a traveler and a theologian in service of the Abbasid Caliphate, little is known about Ahmad Ibn Fadlan prior to 921 and his self-reported travels.
Ibn Fadlan was sent from Baghdad in 921 to serve as the secretary to an ambassador from the Abbasid Caliph al-Muqtadir to the iltäbär of the Volga Bulgaria, Almış. On 21 June 921, a diplomatic party led by Susan al-Rassi, a eunuch in the caliph's court, left Baghdad; the purpose of their mission was to explain Islamic law to the converted Bulgar peoples living on the eastern bank of the Volga River in what is now Russia. Additionally, the embassy was sent in response to a request by the king of the Volga Bulgars to help them against their enemies, the Khazars. Ibn Fadlan served as the group's religious advisor and lead counselor for Islamic religious doctrine and law. Ahmad Ibn Fadlan and the diplomatic party utilized established caravan routes toward Bukhara, now part of Uzbekistan, but instead of following that route all the way to the east, they turned northward in what is now northeastern Iran. Leaving the city of Gurgan near the Caspian Sea, they crossed lands belonging to a variety of Turkic peoples, notably the Khazar Khaganate, Oghuz Turks on the east coast of the Caspian, the Pechenegs on the Ural River, the Bashkirs in what is now central Russia, but the largest portion of his account is dedicated to the Rus, i.e. the Varangians on the Volga trade route.
All told, the delegation covered some 4000 kilometers. Ibn Fadlan's envoy reached the Volga Bulgar capital on 12 May 922; when they arrived, Ibn Fadlan read aloud a letter from the caliph to the Bulgar Khan, presented him with gifts from the caliphate. At the meeting with the Bulgar ruler, Ibn Fadlan delivered the caliph's letter, but was criticized for not bringing with him the promised money from the caliph to build a fortress as defense against enemies of the Bulgars. For a long time, only an incomplete version of the account was known, transmitted as quotations in the geographical dictionary of Yāqūt, published in 1823 by Christian Martin Frähn. Only in 1923 was a manuscript discovered by Zeki Validi Togan in the Astane Quds Museum, Iran; the manuscript, Razawi Library MS 5229, consists of 420 pages. Besides other geographical treatises, it contains a fuller version of Ibn Fadlan's text. Additional passages not preserved in MS 5229 are quoted in the work of the 16th century Persian geographer Amīn Rāzī called Haft Iqlīm.
Neither source seems to record Ibn Fadlān's complete report. Yāqūt offers excerpts, several times claims that Ibn Fadlān recounted his return to Bagdad, but does not quote such material. Meanwhile, the text in Razawi Library MS 5229 breaks off part way through describing the Khazars. One noteworthy aspect of the Volga Bulgars that Ibn Fadlan focused on was their religion and the institution of Islam in these territories; the Bulgar king had invited religious instruction as a gesture of homage to the Abbasids in exchange for financial and military support, Ibn Fadlan's mission as a faqih was one of proselytization as well as diplomacy. For example, Ibn Fadlan details in his encounter that the Volga Bulgar Khan commits an error in his prayer exhortations by repeating the prayer twice. One scholar calls it an “illuminating episode” in the text where Ibn Fadlan expresses his great anger and disgust over the fact that the Khan and the Volga Bulgars in general are practicing some form of imperfect and doctrinally unsound Islam.
In general, Ibn Fadlan recognized and judged the peoples of central Eurasia he encountered by the possession and practice of Islam, along with their efforts put forth to utilize and foster Islamic faith and social practice in their respective society. Many of the peoples and societies to Ibn Fadlan were "like asses gone astray, they have no religious bonds with God, nor do they have recourse to reason". A substantial portion of Ibn Fadlan's account is dedicated to the description of a people he called the Rūs or Rūsiyyah. Western scholarship has assumed that he was describing Volga Vikings, the North Germanic tribes travelling the Volga trade route, though the identification of the people Ibn Fadlān describes is uncertain; the Rūs appear as traders. They are described as having bodie
Muhammad ibn Musa al-Khwarizmi
Muḥammad ibn Mūsā al-Khwārizmī Latinized as Algorithmi, was a Persian scholar who produced works in mathematics and geography under the patronage of the Caliph Al-Ma'mun of the Abbasid Caliphate. Around 820 AD he was appointed as the astronomer and head of the library of the House of Wisdom in Baghdad. Al-Khwarizmi's popularizing treatise on algebra presented the first systematic solution of linear and quadratic equations. One of his principal achievements in algebra was his demonstration of how to solve quadratic equations by completing the square, for which he provided geometric justifications; because he was the first to treat algebra as an independent discipline and introduced the methods of "reduction" and "balancing", he has been described as the father or founder of algebra. The term algebra itself comes from the title of his book, his name gave rise to the terms algorithm. His name is the origin of guarismo and of algarismo, both meaning digit. In the 12th century, Latin translations of his textbook on arithmetic which codified the various Indian numerals, introduced the decimal positional number system to the Western world.
The Compendious Book on Calculation by Completion and Balancing, translated into Latin by Robert of Chester in 1145, was used until the sixteenth century as the principal mathematical text-book of European universities. In addition to his best-known works, he revised Ptolemy's Geography, listing the longitudes and latitudes of various cities and localities, he further produced a set of astronomical tables and wrote about calendaric works, as well as the astrolabe and the sundial. Few details of al-Khwārizmī's life are known with certainty, he was born into a Persian family and Ibn al-Nadim gives his birthplace as Khwarezm in Greater Khorasan. Muhammad ibn Jarir al-Tabari gives his name as Muḥammad ibn Musá al-Khwārizmiyy al-Majūsiyy al-Quṭrubbaliyy; the epithet al-Qutrubbulli could indicate he might instead have come from Qutrubbul, a viticulture district near Baghdad. However, Rashed suggests: There is no need to be an expert on the period or a philologist to see that al-Tabari's second citation should read "Muhammad ibn Mūsa al-Khwārizmī and al-Majūsi al-Qutrubbulli," and that there are two people between whom the letter wa has been omitted in an early copy.
This would not be worth mentioning if a series of errors concerning the personality of al-Khwārizmī even the origins of his knowledge, had not been made. G. J. Toomer... with naive confidence constructed an entire fantasy on the error which cannot be denied the merit of amusing the reader. Regarding al-Khwārizmī's religion, Toomer writes: Another epithet given to him by al-Ṭabarī, "al-Majūsī," would seem to indicate that he was an adherent of the old Zoroastrian religion; this would still have been possible at that time for a man of Iranian origin, but the pious preface to al-Khwārizmī's Algebra shows that he was an orthodox Muslim, so al-Ṭabarī's epithet could mean no more than that his forebears, he in his youth, had been Zoroastrians. Ibn al-Nadīm's Kitāb al-Fihrist includes a short biography on al-Khwārizmī together with a list of the books he wrote. Al-Khwārizmī accomplished most of his work in the period between 813 and 833. After the Muslim conquest of Persia, Baghdad became the centre of scientific studies and trade, many merchants and scientists from as far as China and India traveled to this city, as did al-Khwārizmī.
He worked in Baghdad as a scholar at the House of Wisdom established by Caliph al-Ma’mūn, where he studied the sciences and mathematics, which included the translation of Greek and Sanskrit scientific manuscripts. Douglas Morton Dunlop suggests that it may have been possible that Muḥammad ibn Mūsā al-Khwārizmī was in fact the same person as Muḥammad ibn Mūsā ibn Shākir, the eldest of the three Banū Mūsā. Al-Khwārizmī's contributions to mathematics, geography and cartography established the basis for innovation in algebra and trigonometry, his systematic approach to solving linear and quadratic equations led to algebra, a word derived from the title of his book on the subject, "The Compendious Book on Calculation by Completion and Balancing". On the Calculation with Hindu Numerals written about 820, was principally responsible for spreading the Hindu–Arabic numeral system throughout the Middle East and Europe, it was translated into Latin as Algoritmi de numero Indorum. Al-Khwārizmī, rendered as Algoritmi, led to the term "algorithm".
Some of his work was based on Persian and Babylonian astronomy, Indian numbers, Greek mathematics. Al-Khwārizmī corrected Ptolemy's data for Africa and the Middle East. Another major book was Kitab surat al-ard, presenting the coordinates of places based on those in the Geography of Ptolemy but with improved values for the Mediterranean Sea and Africa, he wrote on mechanical devices like the astrolabe and sundial. He assisted a project to determine the circumference of the Earth and in making a world map for al-Ma'mun, the caliph, overseeing 70 geographers. When, in the 12th century, his works spread to Europe through Latin translations, it had a profound impact on the advance of mathematics in