1.
Syria
–
Syrias capital and largest city is Damascus. Religious groups include Sunnis, Christians, Alawites, Druze, Mandeans, Shiites, Salafis, Sunni Arabs make up the largest religious group in Syria. Its capital Damascus and largest city Aleppo are among the oldest continuously inhabited cities in the world, in the Islamic era, Damascus was the seat of the Umayyad Caliphate and a provincial capital of the Mamluk Sultanate in Egypt. The post-independence period was tumultuous, and a number of military coups. In 1958, Syria entered a union with Egypt called the United Arab Republic. Syria was under Emergency Law from 1963 to 2011, effectively suspending most constitutional protections for citizens, Bashar al-Assad has been president since 2000 and was preceded by his father Hafez al-Assad, who was in office from 1970 to 2000. Mainstream modern academic opinion strongly favours the argument that the Greek word is related to the cognate Ἀσσυρία, Assyria, in the past, others believed that it was derived from Siryon, the name that the Sidonians gave to Mount Hermon. However, the discovery of the inscription in 2000 seems to support the theory that the term Syria derives from Assyria. The area designated by the word has changed over time, since approximately 10,000 BC, Syria was one of centers of Neolithic culture where agriculture and cattle breeding appeared for the first time in the world. The following Neolithic period is represented by houses of Mureybet culture. At the time of the pre-pottery Neolithic, people used vessels made of stone, gyps, finds of obsidian tools from Anatolia are evidences of early trade relations. Cities of Hamoukar and Emar played an important role during the late Neolithic, archaeologists have demonstrated that civilization in Syria was one of the most ancient on earth, perhaps preceded by only those of Mesopotamia. The earliest recorded indigenous civilisation in the region was the Kingdom of Ebla near present-day Idlib, gifts from Pharaohs, found during excavations, confirm Eblas contact with Egypt. One of the earliest written texts from Syria is an agreement between Vizier Ibrium of Ebla and an ambiguous kingdom called Abarsal c.2300 BC. The Northwest Semitic language of the Amorites is the earliest attested of the Canaanite languages, Mari reemerged during this period, and saw renewed prosperity until conquered by Hammurabi of Babylon. Ugarit also arose during this time, circa 1800 BC, close to modern Latakia, Ugaritic was a Semitic language loosely related to the Canaanite languages, and developed the Ugaritic alphabet. The Ugarites kingdom survived until its destruction at the hands of the marauding Indo-European Sea Peoples in the 12th century BC, Yamhad was described in the tablets of Mari as the mightiest state in the near east and as having more vassals than Hammurabi of Babylon. Yamhad imposed its authority over Alalakh, Qatna, the Hurrians states, the army of Yamhad campaigned as far away as Dēr on the border of Elam
2.
Citadel of Damascus
–
The Citadel of Damascus is a large medieval fortified palace and citadel in Damascus, Syria. It is part of the Ancient City of Damascus, which was listed as a UNESCO World Heritage Site in 1979, after the assassination of Atsiz bin Uvak, the project was finished by the Seljuq ruler Tutush I. The emirs of the subsequent Burid and Zengid dynasties carried out modifications, during this period, the citadel and the city were besieged several times by Crusader and Muslim armies. In 1174, the citadel was captured by Saladin, the Ayyubid sultan of Egypt, Saladins brother Al-Adil rebuilt the citadel completely between 1203 and 1216 in response to the development of the counterweight trebuchet. After his death, power struggles broke out between the other Ayyubid princes and although Damascus switched hands several times, the citadel was taken by force only once, in 1239. The citadel remained in Ayyubid hands until the Mongols under their general Kitbuqa captured Damascus in 1260, after an unsuccessful revolt broke out in the citadel, the Mongols had most of it dismantled. After the defeat of the Mongols in 1260 by the Mamluks, except for brief periods in 1300 and 1401, when the Mongols conquered Damascus, the Mamluks controlled the citadel until 1516. In that year, Syria fell into the hands of the Ottoman Empire, Damascus surrendered without a fight and from the 17th century onward the citadel functioned as barracks for the Jannisaries—Ottoman infantry units. The citadel continued to serve as a barracks and prison until 1986, as of 2011, excavation and restoration efforts are still ongoing. The citadel is located in the northwest corner of the city walls, the citadel consists of a more or less rectangular curtain wall enclosing an area of 230 by 150 metres. The walls were protected by 14 massive towers, but today only 12 remain. The citadel has gates on its northern, western and eastern flanks, the current citadel dates primarily to the Ayyubid period while incorporating parts of the older Seljuq fortress. Extensive repairs in response to sieges and earthquakes were carried out in the Mamluk and it is uncertain whether a building stood on the site of the citadel before the 11th century AD. The area occupied by the citadel was most likely outside this first settlement. The presence of a citadel during the Hellenistic period is uncertain, Damascus certainly had a citadel during the Roman period, but whether it was located on the site of the present citadel is uncertain and subject to scholarly debate. In 1076, Damascus was conquered by the Turkman warlord Atsiz bin Uvak and he then tried to invade the Fatimid Caliphate in Egypt but was defeated in 1077. The Fatimids subsequently built on their victory over Atsiz and besieged Damascus in 1077 and again in 1078, the siege of 1078 was eventually lifted by Tutush I, brother of the Seljuq sultan Malik Shah I, to whom Atsiz had appealed for help. After the Fatimid besiegers had left, Tutush I took over the city and, the construction of the citadel was finished under Tutush I
3.
Karst spring
–
A karst spring is a spring that is part of a karst system. That includes the drainage of a much larger area, which means that karst springs often have a very large discharge. Because of their conical or bowl shape, such water sources are also known in German-speaking lands as a Topf which is reflected in names such as Aachtopf or Blautopf. Karst springs are usually the end of a system at the place where a river cave reaches the Earths surface. Thus, it is possible to enter the caves at a karst spring. An estavelle or inversac is a ground orifice which, depending on conditions and season. It is a type of sinkhole, a Vauclusian spring is a spring that originates from a shaft or a cave system, with the water surging upwards under relatively high pressure. It is named after the Fontaine de Vaucluse in southern France, submarine karst springs, also known as vruljas, occur worldwide, and are most numerous in shallow waters of the Mediterranean Sea. The main feature of karst springs results from the fact that water is transported by underground caverns. This means that there is minimal filtering of the water and little separation of different sediments, groundwater emerges at the spring within a few days. Storms, snowmelt, and general changes in rainfall have a very noticeable. Many karst springs dry up during the driest part of the year and are known as intermittent springs. Still others are dry most of the round and only flow after heavy rain. Sources that only flow during wet years are known in German as Hungerbrunnen. It is however more of a culturally related superstition, scientific studies on various Hungerbrunnen have not confirmed such a relationship. An example is the Hungerbrunnen in the parish of Heuchlingen near Gerstetten, the properties of karst springs make them unsuitable for the supply of drinking water. Their uneven flow rate does not support steady rates of consumption, especially in summer there is lower discharge. In addition, poor filtering and high hardness mean that the quality is poor
4.
Canyon
–
A canyon or gorge is a deep cleft between escarpments or cliffs resulting from the erosive activity of a river over geologic timescales. A canyon may also refer to a rift between two peaks, such as those in ranges including the Rocky Mountains, the Alps. Usually a river or stream and erosion carve out such splits between mountains, examples of mountain-type canyons are Provo Canyon in Utah or Yosemite National Park in Californias Sierra Nevada. Canyons within mountains, or gorges that have an opening on one side are called box canyons. Slot canyons are very narrow canyons, often with smooth walls, steep-sided valleys in the seabed of the continental slope underwater are referred to as submarine canyons. Unlike canyons on land, submarine canyons are thought to be formed by turbidity currents, the word canyon is Spanish in origin, with the same meaning. The word canyon is used in North America while the words gorge and ravine are used in Europe and Oceania, though gorge. In the United States, place names generally use canyon in the southwest and gorge in the northeast, in Canada, a gorge is usually narrow while a ravine is more open and often wooded. The military-derived word defile is occasionally used in the United Kingdom, most canyons were formed by a process of long-time erosion from a plateau or table-land level. The cliffs form because harder rock strata that are resistant to erosion, Canyons are much more common in arid than in wet areas because physical weathering has a more localized effect in arid zones. The wind and water from the combine to erode and cut away less resistant materials such as shales. The freezing and expansion of water also serves to help form canyons, water seeps into cracks between the rocks and freezes, pushing the rocks apart and eventually causing large chunks to break off the canyon walls, in a process known as frost wedging. Canyon walls are formed of resistant sandstones or granite. Sometimes large rivers run through canyons as the result of geological uplift. These are called entrenched rivers, because they are unable to alter their course. In the United States, the Colorado River in the Southwest, Canyons often form in areas of limestone rock. As limestone is soluble to an extent, cave systems form in the rock. When these collapse, a canyon is left, as in the Mendip Hills in Somerset and Yorkshire Dales in Yorkshire, England
5.
Banias
–
Banias is the Arabic and modern Hebrew name of an ancient site that developed around a spring once associated with the Greek god Pan. It is located at the foot of Mount Hermon, north of the Golan Heights, the spring is the source of the Banias River, one of the main tributaries of the Jordan River. The first mention of the ancient city during the Hellenistic period was in the context of the Battle of Panium, fought around 200-198 BCE, later the region was called Paneas. Both names were derived from that of Pan, the god of the wild, the spring at Banias initially originated in a large cave carved out of a sheer cliff face which was gradually lined with a series of shrines. The temenos included in its final phase a temple placed at the mouth of the cave, courtyards for rituals and it was constructed on an elevated, 80m long natural terrace along the cliff which towered over the north of the city. A four-line inscription at the base of one of the niches relates to Pan and Echo, the mountain nymph, and was dated to 87 BCE. The once very large spring gushed from the cave, but an earthquake moved it to the foot of the natural terrace where it now seeps quietly from the bedrock. From here the stream, called Nahal Hermon in Hebrew, flows towards what once were the malaria-infested Hula marshes, the pre-Hellenistic deity associated with the spring of Banias was variously called Baal-gad or Baal-hermon. Paneas was first settled in the Hellenistic period following Alexander the Greats conquest of the east, the Ptolemaic kings built a cult centre there in the 3rd century BC. In the Hellenistic Period the spring was named Panias, for the Arcadian goat-footed god Pan, the Latin equivalent for Paneas is Fanium. The spring lies close to the way of the sea mentioned by Isaiah, in extant sections of the Greek historian Polybiuss history of The Rise of the Roman Empire, a Battle of Panium is mentioned. This battle was fought in ca, 200-198 BC between the armies of Ptolemaic Egypt and the Seleucids of Coele-Syria, led by Antiochus III. Antiochuss victory cemented Seleucid control over Phoenicia, Galilee, Samaria and it was these Seleucids who built a pagan temple dedicated to Pan at Paneas. Upon Zenodoruss death in 20 BC, the Panion, including Paneas, was annexed to the Kingdom of Herod the Great, Herod erected a temple of white marble there n honour of his patron. In 61 CE, king Agrippa II renamed the administrative capital Neronias in honour of the Roman emperor Nero, Agrippa also carried out urban improvements. In 67CE, during the First Jewish–Roman War, Vespasian briefly visited Caesarea Philippi before advancing on Tiberias in Galilee, with the death of Agrippa II around the year 92 came the end of Herodian rule, and the city returned to the province of Syria. In the late Roman and Byzantine periods the written sources name the city again as Paneas, in 361, Emperor Julian the Apostate instigated a religious reformation of the Roman state, in which he supported the restoration of Hellenic paganism as the state religion. In Paneas this was achieved by replacing Christian symbols, though the change was short lived, in the 5th century, following the division of the Empire, the city was part of the Eastern Empire, but was lost to the Arab expansion of the 7th century
6.
Hydraulic engineering
–
Hydraulic engineering as a sub-discipline of civil engineering is concerned with the flow and conveyance of fluids, principally water and sewage. One feature of these systems is the use of gravity as the motive force to cause the movement of the fluids. This area of engineering is intimately related to the design of bridges, dams, channels, canals, and levees. Hydraulic engineering is the application of the principles of mechanics to problems dealing with the collection, storage, control, transport, regulation, measurement. Before beginning a hydraulic engineering project, one must figure out how water is involved. The hydraulic engineer is concerned with the transport of sediment by the river, the interaction of the water with its boundary. Fundamentals of Hydraulic Engineering defines hydrostatics as the study of fluids at rest, in a fluid at rest, there exists a force, known as pressure, that acts upon the fluids surroundings. This pressure, measured in N/m2, is not constant throughout the body of fluid, pressure, p, in a given body of fluid, increases with an increase in depth. Four basic devices for measurement are a piezometer, manometer, differential manometer, Bourdon gauge. As Prasuhn states, On undisturbed submerged bodies, pressure acts along all surfaces of a body in a liquid and this reaction is known as equilibrium. More advanced applications of pressure are that on plane surfaces, curved surfaces, dams, the main difference between an ideal fluid and a real fluid is that for ideal flow p1 = p2 and for real flow p1 > p2. Ideal fluid is incompressible and has no viscosity, ideal fluid is only an imaginary fluid as all fluids that exist have some viscosity. A viscous fluid will deform continuously under a force, whereas an ideal fluid doesnt deform. The various effects of disturbance on a flow are stable, transition. For an ideal fluid, Bernoullis equation holds along streamlines, as the flow comes into contact with the plate, the layer of fluid actually adheres to a solid surface. There is then a considerable shearing action between the layer of fluid on the surface and the second layer of fluid. The second layer is forced to decelerate, creating a shearing action with the third layer of fluid. As the fluid passes further along the plate, the zone in which shearing action occurs tends to spread further outwards and this zone is known as the boundary layer
.jpg)
Syria
_p282_PASS_OF_SOOC_BARRADA.jpg)
This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Abana". Encyclopædia Britannica. 1 (11th ed.). Cambridge University Press. p. 6.
This article incorporates text from a publication now in the 
Singer, Isidore; et al., eds. (1901–1906). "Abana". Abana. Jewish Encyclopedia. New York: Funk & Wagnalls Company.