Cartography and Navigation

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Cartography and Navigation

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Some historians have claimed that Arabs were desert travelers who were afraid to travel by sea. It has been well established, however, that long before the rise of Islam, seafarers from the Arabian Peninsula were shipping Arab wares to far-off lands. When one considers the geography of the region, it becomes obvious that areas that eventually came under Muslim rule were located at the hubs of several hemispheric trade routes that extended from northern Europe to China. Western historians tend to focus on trade across the Mediterranean Sea, but equally important trade routes departed from the Red Sea, the Gulf of Aden, the Arabian Sea, the Euphrates River, and the Indian Ocean.

Islam and Trade . Islam arose primarily in a mercantile, rather than a nomadic or agricultural, milieu, although some of the early adherents to the faith were members of nomadic Bedouin tribes of the region. The Prophet Muhammad was a merchant and managed caravans that traveled along the trade routes between Arabia, Palestine, and Syria. The Qur’an mentions trade and points out how God facilitates trade among Muslims and non-Muslims by providing the winds that carry ships to distant lands. By the end of the eighth century, Arab traders had well-developed sea routes to Baghdad, India, Madagascar, Ceylon, Indonesia, and China. The first Arab vessel arrived at Guangcho, China, around the year 787, and for the next five centuries the Arabs held a virtual monopoly on trade between China and the West. These merchants had continued the ancient tradition of following monsoon winds from Arabia to the Indian Ocean. The Arab-Muslim presence was so strong in Canton that the Chinese emperor appointed a Muslim official to govern the area and lead the Friday prayers at the local mosque, which is the oldest one in China. By tracing the production of Muslim coinage, historians have also documented Muslim mercantile activities northward from the Caspian Sea along the Volga River and into the southern regions of Finland, Norway, and Sweden. The Scandinavian traders set up trading posts that developed into commercial towns such as Kiev in present-day Ukraine. Here Arab merchants purchased European goods such as animal pelts, wax, leather, and Slavic captives (from which the English word slave is derived). Other words that have come into English from Muslim traders include check, tariff, coffer, cipher, risk, traffic (in the sense of distribution), and magazine (in the sense of storage facility).

Orienting Worship . In addition to the need for accurate means of plotting trade routes, there were strong religious foundations for the rapid development of geographic skills among Muslims. No matter where Muslims are in the world, they have to pray facing toward Makkah, and they need a good understanding of geography to do so. Also, all Muslims who have sufficient means are expected to make the pilgrimage to Makkah, and there was the concept within Islam of Rihlafi talab al-’ilm (Travel for the Sake of Knowledge), so there was a need for accurate maps.

Scientific Geography . Under the Abbasid dynasty, which moved the political center of Islam to Baghdad in the eighth century, geography began to develop as a science in Muslim culture. Scholars at the Bayt al-Hikmah (House of Wisdom) in Baghdad translated into Arabic the major astronomical text of India, the Surya-siddhanta. Muslims quickly mastered Indian and Persian geographic knowledge and then expanded on it, turning, in particular, to the works of the second-century Greek scholar Ptolemy. The Khalifah al-Ma’mun (ruled 813-833) supported the efforts of Muslim geographers to make a map of the world.

Sacred Geography . Early Muslim geography texts combined scientific geography with sacred, or symbolic, geography, making no sharp distinction between the two. In sacred geography, mountains, rivers, islands, and points of the compass were symbols of the celestial world. The earth was divided into seven different climate zones that corresponded with the belief that the celestial region had seven levels. Each climate was also connected to a planet and a zodiac sign.

Practical Geography . The writings of the ninth-century geographer al-Farghani (called Alfraganus in the West) were of practical use to travelers. Like his contemporaries among Chinese scholars, al-Farghani developed ways to determine location through the calculation of longitude and latitude. Christopher Columbus used al-Farghani’s measurement of the length of the degree when planning the voyage on which he discovered the New World, and he quoted the Muslim scientist in his marginal notes in a fifteenth-century atlas now at the Biblioteca Colombina in Seville. Unfortunately, Columbus did not realize that the Arab mile in which the measurement was expressed was different from the Italian nautical mile he was using, and thus his calculations were inaccurate. The most important achievements in this field, however, were the work of al-Biruni (973 - circa 1050), who is credited with joining mathematics and geography in his Tahdid nihayat al-amakin (The Determination of the Coordinates of Cities). This book is still considered remarkably accurate, even when compared with maps based on satellite photographs and computerized measurements. Perhaps the greatest of all Muslim geographers, al-Biruni is well known for mapping Persia, Central Asia, and India. As the royal geographer to Sultan Mahmud of Ghazna, al-Biruni accompanied the sultan on military expeditions and became an expert on the peoples, cultures, and geography of India. His greatest achievement is probably his Tahqiq al-Hind (Facts About India, circa 1030), one of the earliest works of ethnography and regional geography.

Patronage . As Muslim Spain and Sicily lost territory to the Christians, several Christian rulers adopted the Muslim tradition of gathering renowned scholars at their courts and supporting their studies. The best known of

these Christian scholar-kings was the wealthy and powerful King Roger II of Sicily (ruled 1105-1154), who had studied under Greek and Arabic tutors as a youth. He invited Muslim scholars to join Jews and Christians at his court to work on translating and writing scholarly works. Practicing a lifestyle similar to that of Muslim courts, Roger wore Arab robes and often spoke in Arabic, causing concern among his fellow European monarchs, many of whom were involved in the Crusades against Muslims in the Holy Land. One of the Muslim scholars Roger invited to his court was the geographer al-Idrisi, who—in an effort to create the most scientifically accurate map—gathered together all the known geographic knowledge of their time. To assist al-Idrisi on his project, Roger formed the Academy of Geographers and brought in other scholars to help. This team of geographers began by distinguishing between fables and scientific knowledge—a difficult task at a time when travel to far-off places was arduous and time-consuming. Maps of the period were filled with warnings about dangerous monsters and bizarre creatures said to live in distant lands. The scholars of Roger’s academy had to debate whether there really were humans with crocodile tails, females whose eyes could flash lightning, and people with dogs’ heads who could rip someone apart. Deciding to create a physical, rather than “cultural,” map of the world, al-Idrisi studied the writings of twelve earlier geographers, ten of whom were from the Muslim world. After fifteen years of effort, the final result was Kitab al-Rujari (The Book of Roger), the most important gathering of geographic knowledge up to that time. Al-Idrisi also presented King Roger with a three-hundred-pound solid silver disk bearing a map of the entire known world. Shortly after Roger’s death, his court was attacked by Byzantine invaders. They melted down the silver disk to make weapons and burned the Latin version of the Book of Roger . Al-Idrisi managed to escape with the only remaining copy, written in Arabic, and the work was not translated into Latin again until the seventeenth century, when it caused great excitement in Europe.

Navigational Technology . Heading out to sea was a terrifying experience for ancient and medieval sailors, and history books are filled with stories of ships that became lost and never returned home. Muslim scientists devised several instruments to help mariners determine their location. Of these, the astrolabe is considered the most important. Like the sextant and the quadrant (another Muslim invention), the astrolabe can help the navigator determine his location by measuring the altitude of the stars, sun, moon, and planets, but the astrolabe can also be used to tell time, measure the height of a mountain, and determine latitude and longitude on land. Muslims also made maps of the sea called Portelan charts. Based on zij (star charts) made by Muslim astronomers, Portelan charts also included information about coastlines, tidal conditions, wind directions, weather conditions, and a map of the sea divided into squares of longitude and latitude. Muslim navigators also had compasses. It is uncertain when Muslim navigators first used them at sea, but it is known that Muslim navigators transferred this technology to the West.

Sources

Nafis Ahmad, Muslim Contributions to Geography (New Delhi: Adam, 1945).

Ahmad Y. al-Hassan and Donald R. Hill, Islamic Technology: An Illustrated History (Cambridge & New York: Cambridge University Press / Paris: Unesco, 1986).

David A. King, “Some Illustrations in Islamic Scientific Manuscripts and Their Secrets,” in The Book in the Islamic World , edited by George N. Atiyah (Albany: State University of New York Press, 1995), pp. 149-177.

Seyyed Hossein Nasr, Islamic Science: An Illustrated Study (London: World of Islam Festival Publishing, 1976).

Nasr, Science and Civilization in Islam (Cambridge, Mass.: Harvard University Press, 1968).