Geographie und Kartographie im mittelalterlichen Islam

Geography and cartography in medieval Islam refers to the advancement of geography, cartography and the earth sciences in the medieval Islamic civilization. During the Middle Ages, Islamic geography was driven by a number of factors: the Islamic Golden Age, parallel development of Islamic astronomy and Islamic mathematics, translation of ancient texts (particularly Hellenistic ones) into Arabic, increased travel due to commerce and Hajj (the Islamic pilgrimage), and the "Muslim age of discovery" and "Muslim Agricultural Revolution".

The Tabula Rogeriana, drawn by Muhammad al-Idrisi for Roger II of Sicily in 1154.

After its beginning in the 8th century, Islamic geography was patronized by the Abbasid caliphs of Baghdad. Various Islamic scholars contributed to its development, and the most notable include Al-Khwārizmī, Abū Zayd al-Balkhī (founder of the 'Balkhī school'), Abu Rayhan Biruni and Avicenna. Muslim geography reached its apex with Muhammad al-Idrisi in the 12th century. Later developments took place under Turks, particularly under the Ottoman Empire, with notable scholars such as Mahmud al-Kashgari and Piri Reis.

Impetus

Islamic golden age

Vorlage:See also When the capital of the Muslim world moved to Baghdad in 750, the city became the center study and translation of scientific writings, attracting scholars of all sorts. Learned men enjoyed caliphal patronage, especially of Harun al-Rashid and Al-Mamun. This learning was undertaken by both Muslims and non-Muslims and by those who spoke Arabic, Greek, Hebrew, Persian and Syriac; although Arabic remained the lingua franca and Islam the dominant faith.

Islamic astronomy

Vorlage:See also Muslim Arabs, for various reasons, were interested in astronomy: Bedouin land caravans and sea merchants used them for navigation during the night, and the encouragement given by certain verses of the Qur'an. Interest in astronomy directly led to the belief that earth was a globe. Technologies used for the furtherance of astronomy had immediate applications in geography as well. For example, the astrolabe used in astronomy was also used for celestial navigation and land surveying.

Previous learning

Vorlage:See also Both the Greeks and Romans were known to have made maps and written geographical works. In the case of the Romans this was a natural outcome of the expansion of their empire. Many of these works were studied and translated by Muslims.

Travels

Vorlage:See also Long distance travel created a need for mapping, and travelers often provided the information to achieve the task. While such travel during the medieval period was hazardous, Muslims nonetheless undertook long journeys. One motive for these was the Hajj or the Muslim pilgrimage. Annually, Muslims came to Mecca in Arabia from Africa, Islamic Iberia, Persia and India. Another motive for travels was commerce. Muslims were involved in trade with Europeans, Indians and the Chinese, and Muslim merchants travelled long distances to conduct commercial activities.

Age of discovery

During the Muslim conquests of the seventh and early eighth centuries, Arab armies established the Islamic Arab Empire, reaching from Central Asia to the Iberian Peninsula. An early form of globalization began emerging during the Islamic Golden Age, when the knowledge, trade and economies from many previously isolated regions and civilizations began integrating due to contacts with Muslim explorers, sailors, scholars, traders, and travelers. Subhi Y. Labib has called this period the Pax Islamica, and John M. Hobson has called it the Afro-Asiatic age of discovery, in reference to the Muslim Southwest Asian and North African traders and explorers who travelled most of the Old World, and established an early global economy across most of Asia, Africa, and Europe, with their trade networks extending from the Atlantic Ocean and Mediterranean Sea in the west to the Indian Ocean and China Seas in the east, and even as far as Japan, Korea and the Bering Strait. Arabic silver dirham coins were also being circulated throughout the Afro-Eurasian landmass, as far as sub-Saharan Africa in the south and northern Europe in the north, often in exchange for goods and slaves. In England, for example, the Anglo-Saxon king Offa of Mercia (r. 757-796) had coins minted with the Shahadah in Arabic. These factors helped establish the Arab Empire (including the Rashidun, Umayyad, Abbasid and Fatimid caliphates) as the world's leading extensive economic power throughout the 7th–13th centuries.

Apart from the Nile, Tigris and Euphrates, navigable rivers in the Islamic regions were uncommon, so transport by sea was very important. Navigational sciences were highly developed, making use of a magnetic compass and a rudimentary instrument known as a kamal, used for celestial navigation and for measuring the altitudes and latitudes of the stars. When combined with detailed maps of the period, sailors were able to sail across oceans rather than skirt along the coast. According to the political scientist Hobson, the origins of the caravel ship, used for long-distance travel by the Spanish and Portuguese since the 15th century, date back to the qarib used by Andalusian explorers by the 13th century.

Ibn Battuta (1304–1368) was a traveler and explorer, whose account documents his travels and excursions over a period of almost thirty years, covering some 73,000 miles (117,000 km). These journeys covered most of the known Old World, extending from North Africa, West Africa, Southern Europe and Eastern Europe in the west, to the Middle East, Indian subcontinent, Central Asia, Southeast Asia and China in the east, a distance readily surpassing that of his predecessors and his near-contemporary Marco Polo.

History and topics

Map from Mahmud al-Kashgari's Diwanu Lughat at-Turk, showing the 11th century distribution of Turkic tribes.

A map by Estakhri from the text Al-aqalim.

A map of the Persian Gulf by Estakhri.

The Tabula Rogeriana, drawn by Muhammad al-Idrisi for Roger II of Sicily in 1154. Note that the north is at the bottom, and so the map appears "upside down" compared to modern cartographic conventions.

Muslims translated many of the Hellenistic documents. The way in which earlier knowledge reached Muslim scholars is crucial. For example, since Muslims inherited Greek writings directly without the influence of the Latin west, T-O maps play no role in Islamic cartography though popular in the European counterpart. Some of the important Greek writings include the Almagest and the Geographia. Muslim scientists then made many of their own contributions to geography and the earth sciences.

Many Islamic scholars declared a mutual agreement (Ijma) that celestial bodies are round, among them Ibn Hazm (d. 1069), Ibn al-Jawzi (d. 1200), and Ibn Taymiya (d. 1328). Ibn Taymiya said, "Celestial bodies are round—as it is the statement of astronomers and mathematicians—it is likewise the statement of the scholars of Islam". Abul-Hasan ibn al-Manaadi, Abu Muhammad Ibn Hazm, and Abul-Faraj Ibn Al-Jawzi have said that the Muslim scholars are in agreement that all celestial bodies are round. Ibn Taymiyah also remarked that Allah has said, "And He (Allah) it is Who created the night and the day, the sun and the moon. They float, each in a Falak." Ibn Abbas says, "A Falaka like that of a spinning wheel." The word 'Falak' (in the Arabic language) means "that which is round." Ibn Khaldun (d. 1406), in his Muqaddimah, also identified the world as spherical.

Cartography

An important influence in the development of cartography was the patronage of the Abbasid caliph, al-Ma'mun, who reigned from 813 to 833. He commissioned several geographers to re-measure the distance on earth that corresponds to one degree of celestial meridian. Thus his patronage resulted in the refinement of the definition of the mile used by Arabs (mīl in Arabic) in comparison to the stadion used by Greeks. These efforts also enabled Muslims to calculate the circumference of the earth. Al-Mamun also commanded the production of a large map of the world, which has not survived, though it is known that its map projection type was based on Marinus of Tyre rather than Ptolemy. The first terrestrial globe of the Old World was also constructed in the Muslim world during the Middle Ages, by Muslim astronomers and geographers working under Caliph al-Ma'mun in the 9th century. His most famous geographer was Muhammad ibn Mūsā al-Khwārizmī (see Book on the appearance of the Earth below). He set the Prime Meridian of the Old World at the eastern shore of the Mediterranean, 10-13 degrees to the east of Alexandria (the prime meridian previously set by Ptolemy) and 70 degrees to the west of Baghdad. Most medieval Muslim geographers continued to use al-Khwarizmi's prime meridian. Other prime meridians used were set by Abū Muhammad al-Hasan al-Hamdānī and Habash al-Hasib al-Marwazi at Ujjain, a centre of Indian astronomy, and by another anonymous writer at Basra.

In the mid-9th century, Estakhri wrote the General Survey of Roads and Kingdoms. It was the first non-East Asian geographical work to make a reference to Korea. Also in the 9th century, the Persian mathematician and geographer, Habash al-Hasib al-Marwazi, employed the use spherical trigonometry and map projection methods in order to convert polar coordinates to a different coordinate system centred on a specific point on the sphere, in this the Qibla, the direction to Mecca. Abū Rayhān Bīrūnī (973-1048) later developed ideas which are seen as an anticipation of the polar coordinate system. Around 1025 CE, he was the first to describe a polar equi-azimuthal equidistant projection of the celestial sphere.

In the early tenth century, Abū Zayd al-Balkhī, originally from Balkh, founded the "Balkhī school" of terrestrial mapping in Baghdad. The geographers of this school also wrote extensively of the peoples, products, and customs of areas in the Muslim world, with little interest in the non-Muslim realms. The "Balkhī school", which included geographers such as Estakhri, al-Muqaddasi and Ibn Hawqal, produced world atlases, each one featuring a world map and twenty regional maps.

Suhrāb, a late tenth century Muslim geographer, accompanied a book of geographical coordinates with instructions for making a rectangular world map, with equirectangular projection or cylindrical cylindrical equidistant projection. The earliest surviving rectangular coordinate map is dated to the 13th century and is attributed to Hamdallah al-Mustaqfi al-Qazwini, who based it on the work of Suhrāb. The orthogonal parallel lines were separated by one degree intervals, and the map was limited to Southwest Asia and Central Asia. The earliest surviving world maps based on a rectangular coordinate grid are attributed to al-Mustawfi in the 14th or 15th century (who used invervals of ten degrees for the lines), and to Hafiz-i-Abru (d. 1430).

Regional cartography

Islamic regional cartography is usually categorized into three groups: that produced by the "Balkhī school", the type devised by al-Idrīsī, and the type that are uniquely foundin the Book of curiosities.

The maps by the Balkhī schools were defined by political, not longitudinal boundaries and covered only the Muslim world. In these maps the distances between various "stops" (cities or rivers) were equalized. The only shapes used in designs were verticals, horizontals, 90-degree angles, and arcs of circles; unnecessary geographical details was eliminated. This approach is similar to that used in subway maps, most notable used in the "London Underground Tube Map" in 1931 by Harry Beck.

Al-Idrīsī defined his maps differently. He considered the extent of the known world to be 160° in longitude, and divided the region into ten parts, each 16° wide. In terms of latitude, he portioned the known world into seven 'climes', determined by the length of the longest day. In his maps, many dominant geographical features can be found.

Mathematical geography and geodesy

The Muslim scholars who held to the spherical Earth theory used it in an impeccably Islamic manner, to calculate the distance and direction from any given point on the earth to Mecca. This determined the Qibla, or Muslim direction of prayer. Muslim mathematicians developed spherical trigonometry which was used in these calculations.

Around 830, Caliph al-Ma'mun commissioned a group of astronomers to measure the distance from Tadmur (Palmyra) to al-Raqqah, in modern Syria. They found the cities to be separated by one degree of latitude and the distance between them to be 66 2/3 miles and thus calculated the Earth's circumference to be Vorlage:Convert. Another estimate given was 56 2/3 Arabic miles per degree, which corresponds to 111.8 km per degree and a circumference of 40,248 km, very close to the currently modern values of 111.3 km per degree and 40,068 km circumference, respectively.

Datei:Al-Biruni Afghan stamp.jpg

Abū Rayhān al-Bīrūnī was a polymath who is considered a pioneer in anthropology, geodesy and geology.

In mathematical geography, Abū Rayhān al-Bīrūnī, around 1025, was the first to describe a polar equi-azimuthal equidistant projection of the celestial sphere. He was also regarded as the most skilled when it came to mapping cities and measuring the distances between them, which he did for many cities in the Middle East and western Indian subcontinent. He often combined astronomical readings and mathematical equations, in order to develop methods of pin-pointing locations by recording degrees of latitude and longitude. He also developed similar techniques when it came to measuring the heights of mountains, depths of valleys, and expanse of the horizon, in The Chronology of the Ancient Nations. He also discussed human geography and the planetary habitability of the Earth. He hypothesized that roughly a quarter of the Earth's surface is habitable by humans, and also argued that the shores of Asia and Europe were "separated by a vast sea, too dark and dense to navigate and too risky to try" in reference to the Atlantic Ocean and Pacific Ocean.

Abū Rayhān al-Bīrūnī is also considered the father of geodesy for his important contributions to the field, along with his significant contributions to geography and geology. At the age of 17, al-Biruni calculated the latitude of Kath, Khwarazm, using the maximum altitude of the Sun. Al-Biruni also solved a complex geodesic equation in order to accurately compute the Earth's circumference, which were close to modern values of the Earth's circumference. In his Masudi Canon, His estimate of 6,339.9 km for the Earth radius was only 16.8 km less than the modern value of 6,356.7 km. In contrast to his predecessors who measured the Earth's circumference by sighting the Sun simultaneously from two different locations, al-Biruni developed a new method of using trigonometric calculations based on the angle between a plain and mountain top which yielded more accurate measurements of the Earth's circumference and made it possible for it to be measured by a single person from a single location. Biruni's method was intended to avoid "walking across hot, dusty deserts" and the idea came to him when he was on top of a tall mountain in India, From the top of the mountain, he sighted the dip angle which, along with the mountain's height (which he calculated beforehand), he applied to the law of sines formula. This was the earliest known use of dip angle and the earliest practical use of the law of sines. He also made use of algebra to formulate trigonometric equations and used the astrolabe to measure angles. His method can be summarized as follows:

He first calculated the height of the mountain by going to two points at sea level with a known distance apart and then measuring the angle between the plain and the top of the mountain for both points. He made both the measurements using an astrolabe. He then used the following trigonometric formula relating the distance (d) between both points with the tangents of their angles (θ) to determine the height (h) of the mountain:

$h={\frac {d\ tan{\theta _{1}}tan{\theta _{2}}}{tan{\theta _{2}}-tan{\theta _{1}}}}$

He then stood at the highest point of the mountain, where he measured the dip angle using an astrolabe. He applied the values he obtained for the dip angle and the mountain's height to the following trigonometric formula in order to calculate the Earth's radius:

$R={\frac {h\ \cos {\theta }}{1-\cos {\theta }}}$

where

• R = Earth radius
• h = height of mountain
• θ = dip angle

John J. O'Connor and Edmund F. Robertson write in the MacTutor History of Mathematics archive:

Al-Biruni had, by the age of 22, also written several short works, including a study of map projections, Cartography, which included a method for projecting a hemisphere on a plane. Biruni's Kitab al-Jawahir (Book of Precious Stones) described minerals such as stones and metals in depth, and was regarded as the most complete book on mineralogy in his time. He conducted hundreds of experiments to gauge the accurate measurements of items he catalogued, and he often listed them by name in a number of different languages, including Arabic, Persian, Greek, Syriac, Hindi, Latin, and other languages. In the Book of Precious Stones, he catalogued each mineral by its color, odor, hardness, density and weight. The weights for many of these minerals he measured were correct to three decimal places of accuracy, and were almost as accurate as modern measurements for these minerals.

Muslim astronomers and geographers were aware of magnetic declination by the 15th century, when the Egyptian Muslim astronomer 'Izz al-Din al-Wafa'i (d. 1469/1471) measured it as 7 degrees from Cairo.

Bio-geography

Many medieval Arabs had interests in the distribution and classification of plants and animals and evolution of life.

Islamic scholars attempted plant analysis. This was of particular interest to physicians who attempted to use herbs for treatment of illness. They classified plants by whether or not they possessed an erect stem, and then further by whether they produced fruits or flowers, root fibers, the types of leaves and bark. Geographers also distinguished plants by the nature of earth (sand, alkaline soil, shore of a body of salt water, in freshwater lakes, hard rock etc.) they grew in and determined their distribution on this basis. Islamic geographers also collected data on the seasonal distribution of plants (based on temperature and precipitation) and used this to classify ecological regions (such as tundra, forests, grasslands, deserts).

Geology, mineralogy, and paleontology

Fielding H. Garrison wrote in the History of Medicine: Vorlage:Quote

Geber (Jabir ibn Hayyan), in the 8th century, is credited with the discovery of crystallization as a purification process, an important contribution to crystallography. He also contributed to geology,oi as George Sarton, the father of the history of science, notes in the Introduction to the History of Science:

Abū Rayhān Bīrūnī

Among his writings on geology, Abū Rayhān Bīrūnī (974-1048) observed the geology of India and discovered that the Indian subcontinent was once a sea, hypothesizing that it became land through the drifting of alluvium. He wrote:

In his Book of Coordinates, Biruni described the existence of shells and fossils in regions that once housed seas and later evolved into dry land. Based on this discovery, he realized that the Earth is constantly evolving. He thus viewed the Earth as a living entity, which was in agreement with his Islamic belief that nothing is eternal and opposed to the ancient Greek belief that the universe is eternal. He further proposed that the Earth had an age, but that its origin was too distant to measure.

Biruni writes the following on the geological changes on the surface of the Earth over a long period of time:

As an example, he cites the 9th century Persian astronomer Abu'l Abbas al-Iranshahri who discovered the roots of a palm tree under dry land, to support his theory that sea turns into land and vice versa over a long period of time. He then writes:

Another example he cites is the Arabian desert which, like India, was also a sea at one time. He writes that the Arabian desert was a sea at one time and became land as it became filled by sand. He then goes on to discuss paleontology, writing that various fossils have been found in that region, including bones and glass, which could not have been buried there by anyone. He also writes about the discovery of:

It should be noted that he used the term "fish-ears" to refer to fossils. He then writes about how, a long time ago, the ancient Arabs must have lived on the mountains of Yemen when the Arabian desert was a sea. He also writes about how the Karakum Desert between Jurjan and Khwarezm must have been a lake at one time, and about how the Amu Darya (Oxus) river must have extended up to the Caspian Sea. This is in agreement with the modern geological theory of a Mesozoic Sea, the Tephys, covering the whole of Central Asia and extending from the Mediterranean Sea to New Zealand.

Ibn Sina (Avicenna)

Ibn Sina (Avicenna, 981-1037) made significant contributions to geology and the natural sciences (which he called Attabieyat) along with other natural philosophers such as Ikhwan AI-Safa and many others. He wrote an encyclopaedic work entitled “Kitab al-Shifa” (The Book of Healing) (1027), in which Part 2, Section 5, contains his essay on mineralogy and meteorology, in six chapters: formation of mountains; the advantages of mountains in the formation of clouds; sources of water; origin of earthquakes; formation of minerals; and the diversity of earth’s terrain. These principles were later known in the Renaissance of Europe as the law of superposition of strata, the concept of catastrophism, and the doctrine of uniformitarianism. These concepts were also embodied in the Theory of the Earth by James Hutton in the Eighteenth century C.E. Academics such as Toulmin and Goodfield (1965), commented on Avicenna's contribution: "Around A.D. 1000, Avicenna was already suggesting a hypothesis about the origin of mountain ranges, which in the Christian world, would still have been considered quite radical eight hundred years later".

Ibn Sina's scientific methodology of field observation was also original in the Earth sciences, and remains an essential part of modern geological investigations. He also hypothesized on the causes of mountains:

The concept of uniformitarianism in geological processes can be traced back to Ibn Sina's The Book of Healing. While discussing the origins of mountains in The Book of Healing, Ibn Sina was also the first to outline one of the principles underlying geologic time scales, the law of superposition of strata:

In natural history, The Book of Healing was the first book to treat the three kingdoms (the mineral, vegetable and animal kingdoms) together systematically, and it contains the most extensive medieval discussion on geology and the mineral kingdom. It describes the structure of a meteor, dealt with the formation of sedimentary rocks, and the role of earthquakes in mountain formation. Ibn Sina also displays a clear awareness of the possibility of seas turning into dry land and vice-versa, and therefore provides a correct explanation for the discovery of fossils on mountain tops. Ibn Sina's theory on the formation of metals combined Geber's sulfur-mercury theory from Islamic alchemy (although he was critic of alchemy) with the mineralogical theories of Aristotle and Theophrastus. He created a synthesis of ideas concerning the nature of the mineral and metallic states.

Ibn Sina also contributed to paleontology with his explanation of how the stoniness of fossils was caused in The Book of Healing. Aristotle previously explained it in terms of vaporous exhalations, which Ibn Sina modified into the theory of petrifying fluids (succus lapidificatus), which was accepted in some form by most naturalists by the 16th century and was elaborated on by Albert of Saxony in the 19th century. Ibn Sina gave the following explanation for the origin of fossils from the petrifaction of plants and animals:

Due to his fundamental contributions to the development of geology, partciularly regarding the origins of mountains, Avicenna is considered fully entitled to be called the 'Father of Geology'.

Human environment

An important topic of Islamic geography was the study of mankind. In general Arab scholars had divided different peoples in the climatic regions they inhabited. These regions were defined by topography, availability of water, natural vegetation, surface altitude and proximity to mountains and seas. Using this geographers estimated the habitable regions of earth.

Geographers also studied the impact of urban environment on human life, as opposed to living in the wilderness. It was thought that such environments block fresh air, and the removal of dust by wind (which then accumulated). It was also concluded that urban settlements were more prone to the spread of epidemics.

While most scholars simply described people inhabiting different regions, Al-Mas'ūdi correlates human characteristics with their environment. For example he argues that because the air in Egypt is stagnant the residents tend to have dark complexion. Similarly Ibn Rusta claimed that people of intermediate type of physique existed near the tropic of cancer where the climate is neither too cold nor too hot.

Meteorology

In the 9th century, Al-Kindi (Alkindus) was the first to introduce experimentation into the Earth sciences. He wrote a treatise on meteorology entitled Risala fi l-Illa al-Failali l-Madd wa l-Fazr (Treatise on the Efficient Cause of the Flow and Ebb), in which he presents an argument on tides which "depends on the changes which take place in bodies owing to the rise and fall of temperature." He describes the following clear and precise laboratory experiment in order to prove his argument:

In the 10th century, Ibn Wahshiyya's Nabatean Agriculture discusses the weather forecasting of atmospheric changes and signs from the planetary astral alterations; signs of rain based on observation of the lunar phases, nature of thunder and lightning, direction of sunrise, behaviour of certain plants and animals, and weather forecasts based on the movement of winds; pollenized air and winds; and formation of winds and vapours. As weather forecasting predictions and the measurement of time and the onset of seasons became more precise and reliable, Muslim agriculturalists became informed of these advances and often employed them in agriculture, making it possible for them to plan the growth of each of their crops at specific times of the year.

In 1021, Ibn al-Haytham (Alhazen), an Iraqi scientist, introduces the scientific method in his Book of Optics. He writes on the atmospheric refraction of light, for example, the cause of morning and evening twilight. He endeavored by use of hyperbola and geometric optics to chart and formulate basic laws on atmospheric refraction. He provides the first correct definition of the twilight, discusses atmospheric refraction, shows that the twilight is due to atmospheric refraction and only begins when the Sun is 19 degrees below the horizon, and uses a complex geometric demonstration to measure the height of the Earth's atmosphere as 52,000 passuum (49 miles), which is very close to the modern measurement of Vorlage:Convert. He also realized that the atmosphere also reflects light, from his observations of the sky brightening even before the Sun rises. Ibn al-Haytham later publishes his Risala fi l-Daw’ (Treatise on Light) as a supplement to his Book of Optics. He discusses the meteorology of the rainbow, the density of the atmosphere, and various celestial phenomena, including the eclipse, twilight and moonlight. Also in the early 11th century, Ibn Sina invented the air thermometer.

In the late 11th century, Abu 'Abd Allah Muhammad ibn Ma'udh, who lived in Al-Andalus, wrote a work on optics later translated into Latin as Liber de crepisculis, which was mistakenly attributed to Alhazen. This was a short work containing an estimation of the angle of depression of the sun at the beginning of the morning twilight and at the end of the evening twilight, and an attempt to calculate on the basis of this and other data the height of the atmospheric moisture responsible for the refraction of the sun's rays. Through his experiments, he obtained the accurate value of 18°, which comes close to the modern value.

In 1121, Al-Khazini, a Muslim scientist of Byzantine Greek descent, publishes the The Book of the Balance of Wisdom, the first study on the hydrostatic balance. In the late 13th century and early 14th century, Qutb al-Din al-Shirazi and his student Kamāl al-Dīn al-Fārisī continued the work of Ibn al-Haytham, and they were the first to give the correct explanations for the rainbow phenomenon.

Applications

Agricultural sciences

During the Muslim Agricultural Revolution, Muslim scientists made significant advances in botany and laid the foundations of agricultural science. Muslim botanists and agriculturists demonstrated advanced agronomical, agrotechnical and economic knowledge in areas such as meteorology, climatology, hydrology, soil occupation, and the economy and management of agricultural enterprises. They also demosntrated agricultural knowledge in areas such as pedology, agricultural ecology, irrigation, preparation of soil, planting, spreading of manure, killing herbs, sowing, cutting trees, grafting, pruning vine, prophylaxis, phytotherapy, the care and improvement of cultures and plants, and the harvest and storage of crops.

Al-Dinawari (828-896) is considered the founder of Arabic botany for his Book of Plants, in which he described at least 637 plants and discussed plant evolution from its birth to its death, describing the phases of plant growth and the production of flowers and fruit.

In the early 13th century, the Andalusian-Arabian biologist Abu al-Abbas al-Nabati developed an early scientific method for botany, introducing empirical and experimental techniques in the testing, description and identification of numerous materia medica, and separating unverified reports from those supported by actual tests and observations. His student Ibn al-Baitar published the Kitab al-Jami fi al-Adwiya al-Mufrada, which is considered one of the greatest botanical compilations in history, and was a botanical authority for centuries. It contains details on at least 1,400 different plants, foods, and drugs, 300 of which were his own original discoveries. The Kitab al-Jami fi al-Adwiya al-Mufrada was also influential in Europe after it was translated into Latin in 1758.

Pollution and waste management

The earliest known treatises dealing with environmentalism and environmental science, especially pollution, were Arabic treatises written by al-Kindi, al-Razi, Ibn Al-Jazzar, al-Tamimi, al-Masihi, Avicenna, Ali ibn Ridwan, Abd-el-latif, and Ibn al-Nafis. Their works covered a number of subjects related to pollution such as air pollution, water pollution, soil contamination, municipal solid waste mishandling, and environmental impact assessments of certain localities. Cordoba, al-Andalus also had the first waste containers and waste disposal facilities for litter collection.

Exploration

See Age of discovery above

The navigation skills learned by Muslim geographers were passed on to Arab and Persian navigators. This in turn led to long distance travel which brought back geographical knowledge of far off lands and islands. By the ninth century, navigation in the Indian Ocean had reached India, Sri Lanka, Malaya and Java in the east, and the east coast of Africa up to Madagascar in the west. Muslim navigators of the some period also explored China, Japan, Korea, and according to some reports the Bering Strait.

During the medieval times Muslims made many journeys to China via the sea. Two geographers, Sulaiman and Abu Zaid, led many journeys and brought back valuable information about China and the path they took to it. They wrote literature on climate of the coast of China warning navigators of storms. They also prepared a list of potential agricultural imports from China, including exotic herbs hitherto unknown to Muslims.

On land Muslims explored Central Asia and southeastern Europe. They tried to determine, unsuccessfully, the origins of the river Nile. In doing so, however, Arabs explored Sudan, the Sahara, reaching sub-Saharan regions such as Senegal and Nigeria.

In the 14th century, Ibn Baṭṭūṭah, a Moroccan, began his travels. He started as a pilgrim to Mecca, but continued his journeys for the next 30 years. Before returning home, he had visited most of the Muslim world, from southern Africa to eastern Asia. The universal use of Arabic and his status as judge trained in law gave him access to royal courts at most locations he visited.

Instruments

An alidade.

Alidade

The alidade was invented in the Islamic world, while the term "alhidade" is itself derived from Arabic.

Astrolabes were used as navigational instruments by Muslim explorers.

Astrolabe

In the 10th century, al-Sufi first described over 1000 different uses of an astrolabe, in areas as diverse as astronomy, astrology, horoscopes, navigation, surveying, timekeeping, Qibla, Salah, etc. Abu Rayhan Biruni in particular made use of the astrolabe in his measurement of the Earth radius.

Baculus

The baculus, used for nautical astronomy, originates from Islamic Iberia and was later used by Portuguese navigators for long-distance travel.

Cartographic instruments

• Cartographic grids in 10th century Baghdad.
• Cartographic Qibla indicators, which were brass instruments with Mecca-centred world maps and cartographic grids engraved on them in the 17th century.
• Cartographic Qibla indicator with a sundial and compass attached to it, by Muhammad Husayn in the 17th century.

Compass

Muslim physicists and geographers became aware of magnetism after the arrival of an early compass from China around the 12th or 13th century. Navigational sciences became highly developed with use of the magnetic compass. The first astronomical uses of the magnetic compass is found in a treatise on astronomical instruments written by the Yemeni sultan al-Ashraf (d. 1296). This was the first reference to the compass in astronomical literature.

Compass dial

In the 13th century, Ibn al-Shatir invented the compass dial, a timekeeping device incorporating both a universal sundial and a magnetic compass. He invented it for the purpose of finding the times of Salah prayers.

Compass rose

The Arabs invented the 32-point compass rose during the Middle Ages.

Dry compass (Mariner's compass)

In 1282, the Yemeni sultan Al-Ashraf developed an improved compass for use as a "Qibla indicator" instrument in order to find the direction to Mecca. Al-Ashraf's instrument was one of the earliest dry compasses, and appears to have been invented independently of Peter Peregrinus. The dry compass is commonly known as the "Mariner's compass".

Kamal

Arab navigators invented a rudimentary sextant known as a kamal, used for celestial navigation and for measuring the altitudes and latitudes of the stars, in the late 9th century. They employed in the Indian Ocean from the 10th century, They employed it in the Indian Ocean from the 10th century, and it was adopted by Indian navigators soon after, followed by Chinese navigators some time before the 16th century. The invention of the kamal allowed for the earliest known latitude sailing, and was thus the earliest step towards the use of quantitative methods in navigation.

The planisphere, the earliest star chart, was invented by Abū Rayhān al-Bīrūnī.

Navicula de Venetiis

This was a universal horary dial invented in 9th century Baghdad. It was used for accurate timekeeping by the Sun and Stars, and could be observed from any latitude. This was later known in Europe as the "Navicula de Venetiis", which was considered the most sophisticated timekeeping instrument of the Renaissance.

Navigational astrolabe

The first navigational astrolabe was invented in the Islamic world during the Middle Ages, and employed the use of a polar projection system.

Nilometer

The first Nilometer was built in Egypt in 861. Its construction was ordered by the Abbasid Caliph Al-Mutawakkil.

Orthographical astrolabe

Abu Rayhan al-Biruni invented and wrote the earliest treatise on the orthographical astrolabe in the 1000s.

Planisphere and star chart

In the early 11th century, Abū Rayhān al-Bīrūnī invented and wrote the first treatise on the planisphere, which was the earliest star chart and an early analog computer.

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The first terrestrial globe of the Old World was created under al-Ma'mun.

Shadow square

The shadow square was an instrument used to determine the linear height of an object, in conjunction with the alidade, for angular observations. It was invented by Muhammad ibn Mūsā al-Khwārizmī in 9th century Baghdad.

The torquetum was invented by Jabir ibn Aflah (Geber).

Terrestrial globe

The first terrestrial globe of the Old World was constructed in the Muslim world during the Middle Ages, by Muslim geographers and astronomers working under the Abbasid caliph, Al-Ma'mun, in the 9th century.

Torquetum

Jabir ibn Aflah (Geber) (c. 1100-1150) invented the torquetum, an observational instrument and mechanical analog computer device used to transform between spherical coordinate systems. It was designed to take and convert measurements made in three sets of coordinates: horizon, equatorial, and ecliptic.

Universal astrolabe (Saphaea)

The first universal astrolabes were constructed in the Islamic world. Unlike their predecessors, they did not depend on the latitude of the observer and could be used anywhere on the Earth. The basic idea for a latitude-independent astrolabe was conceived in the 9th century by Habash al-Hasib al-Marwazi in Baghdad and the topic was later discussed in the early 11th century by Al-Sijzi in Persia. The first known universal astrolabe to be constructed was by Ali ibn Khalaf al-Shakkaz, an Arabic herbalist or apothecary in 11th century Al-Andalus. Another, more advanced and more famous, universal astrolabe was constructed by Abū Ishāq Ibrāhīm al-Zarqālī (Arzachel) soon after. His instrument became known in Europe as the "Saphaea". It was a universal lamina (plate) which "constituted a universal device representing a stereographic projection for the terrestrial equator and could be used to solve all the problems of spherical astronomy for any latitude."

The Grand Turk, a three-masted vessel.

The caravel was invented in 13th-century Islamic Iberia.

Navigational transport

Caravel

The origins of the caravel ship, used for long distance travel by the Portuguese and Spanish since the 15th century, date back to the qarib used by explorers from Islamic Iberia in the 13th century.

Corn-grinding carriage

In the 16th century, Fathullah Shirazi invented an unusual corn-grinding carriage, which was called comfortable by Abu'l-Fazl ibn Mubarak. It could be used to grind corn, when not transporting passengers.

Naval trawler

The TS Pelican, a Vorlage:Convert naval trawler was converted to use the lateen rigging that had been used by the Barbary pirates for naval warfare from the 16th century.

Permanent sternpost-mounted rudder

The Arab ships used a sternpost-mounted rudder which differed technically from both its European and Chinese counterparts. On their ships "the rudder is controlled by two lines, each attached to a crosspiece mounted on the rudder head perpendicular to the plane of the rudder blade." The earliest evidence comes from the Ahsan al-Taqasim fi Marifat al-Aqalim ('The Best Divisions for the Classification of Regions') written by al-Muqaddasi in 985:

According to Lawrence V. Mott, the "idea of attaching the rudder to the sternpost in a relatively permanent fashion, therefore, must have been an Arab invention independent of the Chinese."

Postal system

An important postal system was created in the Islamic world by the caliph Mu'awiyya; the service was called barid, by the name of the towers built to protect the roads by which couriers travelled. Homing pigeons and carrier pigeons were often used in a pigeon post system early as 1150 in Baghdad.

Three-masted merchant vessel

According to John M. Hobson, Muslim sailors introduced the large three-masted merchant vessels around the Mediterranean Sea, though they may have borrowed the three-mast system from Chinese ships. However, Howard I. Chapelle argues that some ancient Roman ships may have also been three-masted cargo ships, though Kevin Greene writes that three-masted ships were not developed until the 15th century.

A Moorish ambassador of the Barbary States to the court of Queen Elizabeth I of England in 1600.

Windward ship

The first windward ship, which could sail into the wind without slowing down, was the TS Pelican employed by the Barbary pirates from the 16th century. It was able to sail at nearly Vorlage:Convert at 38 degrees off the relative wind. Graham Neilson, who reconstructed the ship, wrote: “The Pelican can sail over 20 degrees nearer the wind than any square rigger at sea. The yards come to within 18 degrees of the centreline. It is a combination of the fore and aft and the square sails, along with the aerodynamics, that is the secret of how to move so close to the wind. I think we can get more out of her. It could really tear up the field in a tall ships race.”

Xebec and Polacca

The Xebec and Polacca, which were sailing ships used around the Mediterranean Sea from the 16th to the 19th centuries, originated from the Barbary pirates, who successfully used them for naval warfare against European ships during that time.

Aviation

Parachute

In 9th century Islamic Spain, Abbas Ibn Firnas (Armen Firnas) invented a primitive version of the parachute. John H. Lienhard described it in The Engines of Our Ingenuity as follows:

Controlled flight

Abbas Ibn Firnas was the first to make an attempt at controlled flight, as opposed to earlier gliding attempts in ancient China which were not controllable. Ibn Firnas manuipulated the flight controls of his hang glider using two sets of artificial wings to adjust his altitude and to change his direction. He successfully returned to where he had lifted off from, but his landing was unsuccessful.

According to Philip Hitti in History of the Arabs:

Hang glider

Abbas Ibn Firnas possibly built the first hang glider, though there were earlier instances of manned kites being used in ancient China. Knowledge of Firman and Firnas' flying machines spread to other parts of Europe from Arabic references.

Notable works

The world map by Muhammad al-Idrisi (1154) shown as a globe upside-down.

Part of the Piri Reis map (1513) showing Europe and the Mediterranean Basin.

Surviving fragment of the first World Map of Piri Reis (1513) showing parts of the Americas and possibly Antarctica.

Book on the appearance of the Earth

Muhammad ibn Mūsā al-Khwārizmī's Vorlage:Transl ("Book on the appearance of the Earth") was completed in 833. It is a revised and completed version of Ptolemy's Geography, consisting of a list of 2402 coordinates of cities and other geographical features following a general introduction.

Al-Khwārizmī, Al-Ma'mun's most famous geographer, corrected Ptolemy's gross overestimate for the length of the Mediterranean Sea (from the Canary Islands to the eastern shores of the Mediterranean); Ptolemy overestimated it at 63 degrees of longitude, while al-Khwarizmi almost correctly estimated it at nearly 50 degrees of longitude. Al-Ma'mun's geographers "also depicted the Atlantic and Indian Oceans as open bodies of water, not land-locked seas as Ptolemy had done." Al-Khwarizmi thus set the Prime Meridian of the Old World at the eastern shore of the Mediterranean, 10-13 degrees to the east of Alexandria (the prime meridian previously set by Ptolemy) and 70 degrees to the west of Baghdad. Most medieval Muslim geographers continued to use al-Khwarizmi's prime meridian.

Book of curiosities

Compiled between 1020 and 1050, this anonymous work contains a series of maps and schematic charts. Dealing with Islamic geography alongside cosmography and map-making, it includes both regional and world maps, many of which are without parallel. Among them are a rectangular schematic map of the Mediterranean area, and the earliest known detailed map (again schematic) of the island Cyprus.

Compendium of the languages of the Turks

Qarakhanid scholar Mahmud al-Kashgari compiled a "Compendium of the languages of the Turks" in the 11th century. The manuscript is illustrated with a "Turkocentric" world map, oriented with east (or rather, perhaps, the direction of midsummer sunrise) on top, centered on the ancient city of Balasagun in what is now Kyrgyzstan, showing the Caspian Sea to the north, and Iraq, Azerbaijan, Yemen and Egypt to the west, China and Japan to the east, Hindustan, Kashmir, Gog and Magog to the south. Conventional symbols are used throughout- blue lines for rivers, red lines for mountain ranges etc. The world is shown as encircled by the ocean. The map is now kept at the Pera Museum in Istanbul.

Tabula Rogeriana

→ Hauptartikel: Tabula Rogeriana

The Arab geographer Muhammad al-Idrisi incorporated the knowledge of Africa, the Indian Ocean and the Far East gathered by Arab merchants and explorers with the information inherited from the classical geographers to create the most accurate map of the world up until his time. It remained the most accurate world map for the next three centuries.

The Tabula Rogeriana was drawn by Al-Idrisi in 1154 for the Norman King Roger II of Sicily, after a stay of eighteen years at his court, where he worked on the commentaries and illustrations of the map. The map, written in Arabic, shows the Eurasian continent in its entirety, but only shows the northern part of the African continent.

On the work of al-Idrisi, S. P. Scott commented:

Kitab-ı Bahriye

The Muslim Ottoman cartographer Piri Reis published navigational maps in his Kitab-ı Bahriye. The work includes an atlas of charts for small segments of the mediterranean, accompanied by sailing instructions covering the sea. In the second version of the work, he included a map of the Americas. The Piri Reis map drawn by the Ottoman cartographer Piri Reis in 1513, is the oldest surviving Islamic map to show the Americas, and perhaps the first to include Antarctica. His map of the world was considered the most accurate in the 16th century.

References

• Alavi, S. M. Ziauddin (1965), Arab geography in the ninth and tenth centuries, Aligarh: Aligarh University Press
• Edson, E; Savage-Smith E, Medieval Views of the Cosmos, Bodleian Library, University of Oxford
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• Mott, Lawrence V. (May 1991), The Development of the Rudder, A.D. 100-1337: A Technological Tale, Thesis, Texas A&M University
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External links

• A review of Muslim Geography
• Islamic Geography in the Middle Ages

See also

• List of Muslim geographers
• Islamic Golden Age
• Islamic science
  • Islamic physics
  • List of Arab scientists and scholars
  • Timeline of Muslim scientists and engineers
• History of geography
  • Chinese geography
• History of cartography