The United Kingdom the United Kingdom of Great Britain and Northern Ireland, sometimes referred to as Britain, is a sovereign country located off the north-western coast of the European mainland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, many smaller islands. Northern Ireland is the only part of the United Kingdom that shares a land border with another sovereign state, the Republic of Ireland. Apart from this land border, the United Kingdom is surrounded by the Atlantic Ocean, with the North Sea to the east, the English Channel to the south and the Celtic Sea to the south-west, giving it the 12th-longest coastline in the world; the Irish Sea lies between Great Ireland. With an area of 242,500 square kilometres, the United Kingdom is the 78th-largest sovereign state in the world, it is the 22nd-most populous country, with an estimated 66.0 million inhabitants in 2017. The UK is constitutional monarchy; the current monarch is Queen Elizabeth II, who has reigned since 1952, making her the longest-serving current head of state.
The United Kingdom's capital and largest city is London, a global city and financial centre with an urban area population of 10.3 million. Other major urban areas in the UK include Greater Manchester, the West Midlands and West Yorkshire conurbations, Greater Glasgow and the Liverpool Built-up Area; the United Kingdom consists of four constituent countries: England, Scotland and Northern Ireland. Their capitals are London, Edinburgh and Belfast, respectively. Apart from England, the countries have their own devolved governments, each with varying powers, but such power is delegated by the Parliament of the United Kingdom, which may enact laws unilaterally altering or abolishing devolution; the nearby Isle of Man, Bailiwick of Guernsey and Bailiwick of Jersey are not part of the UK, being Crown dependencies with the British Government responsible for defence and international representation. The medieval conquest and subsequent annexation of Wales by the Kingdom of England, followed by the union between England and Scotland in 1707 to form the Kingdom of Great Britain, the union in 1801 of Great Britain with the Kingdom of Ireland created the United Kingdom of Great Britain and Ireland.
Five-sixths of Ireland seceded from the UK in 1922, leaving the present formulation of the United Kingdom of Great Britain and Northern Ireland. There are fourteen British Overseas Territories, the remnants of the British Empire which, at its height in the 1920s, encompassed a quarter of the world's land mass and was the largest empire in history. British influence can be observed in the language and political systems of many of its former colonies; the United Kingdom is a developed country and has the world's fifth-largest economy by nominal GDP and ninth-largest economy by purchasing power parity. It has a high-income economy and has a high Human Development Index rating, ranking 14th in the world, it was the world's first industrialised country and the world's foremost power during the 19th and early 20th centuries. The UK remains a great power, with considerable economic, military and political influence internationally, it is sixth in military expenditure in the world. It has been a permanent member of the United Nations Security Council since its first session in 1946.
It has been a leading member state of the European Union and its predecessor, the European Economic Community, since 1973. The United Kingdom is a member of the Commonwealth of Nations, the Council of Europe, the G7, the G20, NATO, the Organisation for Economic Co-operation and Development and the World Trade Organization; the 1707 Acts of Union declared that the kingdoms of England and Scotland were "United into One Kingdom by the Name of Great Britain". The term "United Kingdom" has been used as a description for the former kingdom of Great Britain, although its official name from 1707 to 1800 was "Great Britain"; the Acts of Union 1800 united the kingdom of Great Britain and the kingdom of Ireland in 1801, forming the United Kingdom of Great Britain and Ireland. Following the partition of Ireland and the independence of the Irish Free State in 1922, which left Northern Ireland as the only part of the island of Ireland within the United Kingdom, the name was changed to the "United Kingdom of Great Britain and Northern Ireland".
Although the United Kingdom is a sovereign country, Scotland and Northern Ireland are widely referred to as countries. The UK Prime Minister's website has used the phrase "countries within a country" to describe the United Kingdom; some statistical summaries, such as those for the twelve NUTS 1 regions of the United Kingdom refer to Scotland and Northern Ireland as "regions". Northern Ireland is referred to as a "province". With regard to Northern Ireland, the descriptive name used "can be controversial, with the choice revealing one's political preferences"; the term "Great Britain" conventionally refers to the island of Great Britain, or politically to England and Wales in combination. However, it is sometimes used as a loose synonym for the United Kingdom as a whole; the term "Britain" is used both as a synonym for Great Britain, as a synonym for the United Kingdom. Usage is mixed, with the BBC preferring to use Britain as shorthand only for Great Britain and the UK Government, while accepting that both terms refer to the United K
A low-water crossing provides a bridge when water flow is low. Under high-flow conditions, water runs over the precludes vehicular traffic; this approach is cheaper than building a bridge to raise the level of the road above the highest flood stage of a river in developing countries or in semi-arid areas with rare high-volume rain. Low-water crossings can be dangerous; the low-water crossing was developed from the traditional ford. A ford permits vehicular traffic to cross a waterway with wet wheels; the term “low-water crossing” implies that the crossing is dry, while “ford” implies that the crossing is wet. A simple low-water crossing can be constructed with culverts. Culverts are used to carry the water in a stream keeping the crossing surface dry for most of the year. High flows, e.g. spring runoff or flash floods, flow over the top of the crossing, as the culverts are not large enough to carry these flood-type runoff events. A more elaborate low-water bridge will be an engineered concrete structure.
There are thousands of such structures in the western United States. A low-water bridge that accommodates a high daily volume of vehicular traffic will be underwater only a few days per decade. A low-water bridge renders the waterway non-navigable. In all cases this is not a practical concern, since the waterway would be non-navigable except during flood conditions anyway. A low-water bridge is sometimes called a submersible bridge. A true submersible bridge is used on navigable waterways and is lowered into the water; the concept behind low-water crossings is that they are convenient and safe to use in normal conditions. Once the water level rises to the point where it crosses the bridge surface the bridge is unsafe to use, in developed countries this will be indicated by warning signs. An additional hazard is that the bridge surface may become obscured by the water, making it easy to fall off the bridge surface into the deeper and more hazardous water on either side; as a consequence, the line of the submerged bridge is marked with poles or other structures to indicate its course to unwary travelers and emergency users when submerged.
The force of the moving water may be strong enough to physically push the vehicle off the bridge: the higher the percentage of the vehicle in the water, the more the water's force will take the vehicle off the bridge and send it downriver with substantial damage. An additional risk for trying to cross a bridge under water when more than a couple of feet deep, is the possibility of the vehicle's engine stalling; as people will try to get out of the vehicle, they may step into water currents that cause them to fall or be pulled down into the water. As the current during floods is quite strong, it may sweep them downriver and carry them into debris causing injury or death. Despite the obvious dangers and warnings given there are still a significant number of emergencies and deaths attributable to the unwary use of low-water bridges during flood conditions. One attempted solution/deterrent is the Stupid Motorist Law in the American state of Arizona. Drivers who become stranded on flooded low-water bridges are charged with the cost incurred by emergency services to come to their rescue.
Since 1980, the ecological impact of road crossings on natural streams and rivers has been recognised. Baffles may be installed along the culvert to provide some fish-friendly alternative, but baffles can reduce drastically the culvert discharge capacity for a given afflux, thus increasing the total cost of the culvert structure to achieve the same design discharge and afflux, or increasing the risk of road flooding in an existing structure. Floodway Design of Irish bridges and causeways in developing countries Low Flow, Mid-Level Stream and Ditch Crossings With Culverts Guidelines for Roading and Watercourse Crossings List of Fords and Irish Bridges in the UK Upstream fish passage in box culverts: how do fish and turbulence interplay? by Dr Hang Wang and Professor Hubert Chanson, School of Civil Engineering, University of Queensland
Falsework consists of temporary structures used in construction to support a permanent structure until its construction is sufficiently advanced to support itself. For arches, this is called centering. Falsework includes temporary support structures for formwork used to mold concrete in the construction of buildings and elevated roadways; the British Standards of practice for falsework, BS 5975:2008, defines falsework as "Any temporary structure used to support a permanent structure while it is not self-supporting." Falsework was employed in viaduct construction since ancient times. The Romans were renown for its use, as at the Limyra Bridge in Turkey; until the turn of the 20th century all falsework was constructed from timber. To compensate for timber shortages in different regions and to rationalize labor and material usage, new systems were developed; the major developments include the design of connection devices, transitions to other spanning beams such as steel pipes or profiles or reusable timber beams, adjustable steel props.
In 1935 W. A. de Vigier designed an adjustable steel prop which revolutionized many aspects of the construction industry including to support slab formwork, wall formwork, trench sheeting and falsework. Materials from which falsework systems are manufactured have diversified from traditional steel and timber to aluminium components. In the UK, BS 5975 gives recommendations for the use of falsework on construction sites, it was first introduced by the British Standards Institute in March 1982 and the third version was published in 2008 with Amendment 1 in 2011. The new revisions bring the code up to date with methodology developed in the new CDM 2007 regulations and the requirements of the new European codes EN 12811-1:2003 Temporary works equipment - Part 1: Scaffolds, EN 12812:2004, Falsework - Performance requirements and general design. Fabrication: Metalworkers fabricate a falsework section from pipe and beams. Erection: A section is lifted to a vertical position with the assistance of two forklift operators.
Placement: The section is guided into position by a ground crew. Completed Falsework: Decking and some formwork has been added. Here we see the use of modern pipe-column falsework, used to support the formwork for a post-tensioned reinforced concrete flyover connector for the eastern span replacement of the San Francisco-Oakland Bay Bridge; when the supports are complete, wood beams and plywood or reusable metal forms will be placed and tenon conduits added, concrete poured. After curing and any tenon tensioning, wedges will be removed and forms and falsework disassembled. A certain type of bridge, the self-anchored suspension bridge, must be supported during construction, either by the use of cantilever or suspension methods or by support from below. Support from below was used in the construction of the main span of the eastern span replacement of the San Francisco–Oakland Bay Bridge, using parallel prefabricated truss spans. Cast in place concrete bridges must be supported during construction.
The Sixth Street Viaduct in Los Angeles, California will be cast on falsework and hung on its network tied arch cables. The release of the falsework will coincide with the tensioning of the arch cables. Soffit: Plywood sheeting for walking platform and surface to pour bridge against on top of 4x4 lumber at specified spacing of 12". Camber: Plywood strips that compensate for beam deflection Stringer: Steel beam that ties caps together Top Cap: Steel Beam Post: Steel Pipe or 12x12 lumber. Bottom Cap: Steel Beam Wedge Pack: 4x4 lumber cut into wedges for falsework adjustment, various lumber sizes include 2x6s and plywood Corbel: Distribute load to pads. Typical material is 12x12 lumber and steel beams Pad: Distribute load to ground. Most 6x16 lumber. Arch bridge for the use of falsework in bridge construction
Algae is an informal term for a large, diverse group of photosynthetic eukaryotic organisms that are not closely related, is thus polyphyletic. Including organisms ranging from unicellular microalgae genera, such as Chlorella and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to 50 m in length. Most are aquatic and autotrophic and lack many of the distinct cell and tissue types, such as stomata and phloem, which are found in land plants; the largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the Charophyta, a division of green algae which includes, for example and the stoneworts. No definition of algae is accepted. One definition is that algae "have chlorophyll as their primary photosynthetic pigment and lack a sterile covering of cells around their reproductive cells". Although cyanobacteria are referred to as "blue-green algae", most authorities exclude all prokaryotes from the definition of algae.
Algae constitute a polyphyletic group since they do not include a common ancestor, although their plastids seem to have a single origin, from cyanobacteria, they were acquired in different ways. Green algae are examples of algae that have primary chloroplasts derived from endosymbiotic cyanobacteria. Diatoms and brown algae are examples of algae with secondary chloroplasts derived from an endosymbiotic red alga. Algae exhibit a wide range of reproductive strategies, from simple asexual cell division to complex forms of sexual reproduction. Algae lack the various structures that characterize land plants, such as the phyllids of bryophytes, rhizoids in nonvascular plants, the roots and other organs found in tracheophytes. Most are phototrophic, although some are mixotrophic, deriving energy both from photosynthesis and uptake of organic carbon either by osmotrophy, myzotrophy, or phagotrophy; some unicellular species of green algae, many golden algae, euglenids and other algae have become heterotrophs, sometimes parasitic, relying on external energy sources and have limited or no photosynthetic apparatus.
Some other heterotrophic organisms, such as the apicomplexans, are derived from cells whose ancestors possessed plastids, but are not traditionally considered as algae. Algae have photosynthetic machinery derived from cyanobacteria that produce oxygen as a by-product of photosynthesis, unlike other photosynthetic bacteria such as purple and green sulfur bacteria. Fossilized filamentous algae from the Vindhya basin have been dated back to 1.6 to 1.7 billion years ago. The singular alga retains that meaning in English; the etymology is obscure. Although some speculate that it is related to Latin algēre, "be cold", no reason is known to associate seaweed with temperature. A more source is alliga, "binding, entwining"; the Ancient Greek word for seaweed was φῦκος, which could mean either the seaweed or a red dye derived from it. The Latinization, fūcus, meant the cosmetic rouge; the etymology is uncertain, but a strong candidate has long been some word related to the Biblical פוך, "paint", a cosmetic eye-shadow used by the ancient Egyptians and other inhabitants of the eastern Mediterranean.
It could be any color: black, green, or blue. Accordingly, the modern study of marine and freshwater algae is called either phycology or algology, depending on whether the Greek or Latin root is used; the name Fucus appears in a number of taxa. The algae contain chloroplasts. Chloroplasts contain circular DNA like that in cyanobacteria and are interpreted as representing reduced endosymbiotic cyanobacteria. However, the exact origin of the chloroplasts is different among separate lineages of algae, reflecting their acquisition during different endosymbiotic events; the table below describes the composition of the three major groups of algae. Their lineage relationships are shown in the figure in the upper right. Many of these groups contain some members; some retain plastids, but not chloroplasts. Phylogeny based on plastid not nucleocytoplasmic genealogy: Linnaeus, in Species Plantarum, the starting point for modern botanical nomenclature, recognized 14 genera of algae, of which only four are considered among algae.
In Systema Naturae, Linnaeus described the genera Volvox and Corallina, a species of Acetabularia, among the animals. In 1768, Samuel Gottlieb Gmelin published the Historia Fucorum, the first work dedicated to marine algae and the first book on marine biology to use the new binomial nomenclature of Linnaeus, it included elaborate illustrations of seaweed and marine algae on folded leaves. W. H. Harvey and Lamouroux were the first to divide macroscopic algae into four divisions based on their pigmentation; this is the first use of a biochemical criterion in plant systematics. Harvey's four divisions are: red algae, brown algae, green algae, Diatomaceae. At this time, microscopic algae were discovered and reported by a different group of workers studying the Infusoria. Unlike macroalgae, which were viewed as plants, microalgae were considered animals because they are motile; the nonmotile microalgae were sometimes seen as stages of the lifecycle of plants, macroalgae, or animals. Although used as a taxonomic category in some pre-D
Concrete Portland cement concrete, is a composite material composed of fine and coarse aggregate bonded together with a fluid cement that hardens over time—most a lime-based cement binder, such as Portland cement, but sometimes with other hydraulic cements, such as a calcium aluminate cement. It is distinguished from other, non-cementitious types of concrete all binding some form of aggregate together, including asphalt concrete with a bitumen binder, used for road surfaces, polymer concretes that use polymers as a binder; when aggregate is mixed together with dry Portland cement and water, the mixture forms a fluid slurry, poured and molded into shape. The cement reacts chemically with the water and other ingredients to form a hard matrix that binds the materials together into a durable stone-like material that has many uses. Additives are included in the mixture to improve the physical properties of the wet mix or the finished material. Most concrete is poured with reinforcing materials embedded to provide tensile strength, yielding reinforced concrete.
Famous concrete structures include the Panama Canal and the Roman Pantheon. The earliest large-scale users of concrete technology were the ancient Romans, concrete was used in the Roman Empire; the Colosseum in Rome was built of concrete, the concrete dome of the Pantheon is the world's largest unreinforced concrete dome. Today, large concrete structures are made with reinforced concrete. After the Roman Empire collapsed, use of concrete became rare until the technology was redeveloped in the mid-18th century. Worldwide, concrete has overtaken steel in tonnage of material used; the word concrete comes from the Latin word "concretus", the perfect passive participle of "concrescere", from "con-" and "crescere". Small-scale production of concrete-like materials was pioneered by the Nabatean traders who occupied and controlled a series of oases and developed a small empire in the regions of southern Syria and northern Jordan from the 4th century BC, they discovered the advantages of hydraulic lime, with some self-cementing properties, by 700 BC.
They built kilns to supply mortar for the construction of rubble-wall houses, concrete floors, underground waterproof cisterns. They kept the cisterns secret; some of these structures survive to this day. In the Ancient Egyptian and Roman eras, builders discovered that adding volcanic ash to the mix allowed it to set underwater. German archaeologist Heinrich Schliemann found concrete floors, which were made of lime and pebbles, in the royal palace of Tiryns, which dates to 1400–1200 BC. Lime mortars were used in Greece and Cyprus in 800 BC; the Assyrian Jerwan Aqueduct made use of waterproof concrete. Concrete was used for construction in many ancient structures; the Romans used concrete extensively from 300 BC to a span of more than seven hundred years. During the Roman Empire, Roman concrete was made from quicklime, pozzolana and an aggregate of pumice, its widespread use in many Roman structures, a key event in the history of architecture termed the Roman Architectural Revolution, freed Roman construction from the restrictions of stone and brick materials.
It enabled revolutionary new designs in terms of both structural dimension. Concrete, as the Romans knew it, was a revolutionary material. Laid in the shape of arches and domes, it hardened into a rigid mass, free from many of the internal thrusts and strains that troubled the builders of similar structures in stone or brick. Modern tests show that opus caementicium had as much compressive strength as modern Portland-cement concrete. However, due to the absence of reinforcement, its tensile strength was far lower than modern reinforced concrete, its mode of application was different: Modern structural concrete differs from Roman concrete in two important details. First, its mix consistency is fluid and homogeneous, allowing it to be poured into forms rather than requiring hand-layering together with the placement of aggregate, which, in Roman practice consisted of rubble. Second, integral reinforcing steel gives modern concrete assemblies great strength in tension, whereas Roman concrete could depend only upon the strength of the concrete bonding to resist tension.
The long-term durability of Roman concrete structures has been found to be due to its use of pyroclastic rock and ash, whereby crystallization of strätlingite and the coalescence of calcium–aluminum-silicate–hydrate cementing binder helped give the concrete a greater degree of fracture resistance in seismically active environments. Roman concrete is more resistant to erosion by seawater than modern concrete; the widespread use of concrete in many Roman structures ensured that many survive to the present day. The Baths of Caracalla in Rome are just one example. Many Roman aqueducts and bridges, such as the magnificent Pont du Gard in southern France, have masonry cladding on a concrete core, as does the dome of the Pantheon. After the Roman Empire, the use of burned lime and pozzolana was reduced until the technique was all but forgotten between 500 and the 14th century. From the 14th century to the mid-18th century, the use of cement returned; the Canal du Midi was built using concrete in 1670.
The greatest step forward in the modern use
Finland the Republic of Finland, is a country in Northern Europe bordering the Baltic Sea, Gulf of Bothnia, Gulf of Finland, between Norway to the north, Sweden to the northwest, Russia to the east. Finland is situated in the geographical region of Fennoscandia; the capital and largest city is Helsinki. Other major cities are Espoo, Tampere and Turku. Finland's population is 5.52 million, the majority of the population is concentrated in the southern region. 88.7% of the population is Finnish and speaks Finnish, a Uralic language unrelated to the Scandinavian languages. Finland is the eighth-largest country in Europe and the most sparsely populated country in the European Union; the sovereign state is a parliamentary republic with a central government based in the capital city of Helsinki, local governments in 311 municipalities, one autonomous region, the Åland Islands. Over 1.4 million people live in the Greater Helsinki metropolitan area, which produces one third of the country's GDP. Finland was inhabited when the last ice age ended 9000 BCE.
The first settlers left behind artefacts that present characteristics shared with those found in Estonia and Norway. The earliest people were hunter-gatherers; the first pottery appeared in 5200 BCE. The arrival of the Corded Ware culture in southern coastal Finland between 3000 and 2500 BCE may have coincided with the start of agriculture; the Bronze Age and Iron Age were characterised by extensive contacts with other cultures in the Fennoscandian and Baltic regions and the sedentary farming inhabitation increased towards the end of Iron Age. At the time Finland had three main cultural areas – Southwest Finland and Karelia – as reflected in contemporary jewellery. From the late 13th century, Finland became an integral part of Sweden through the Northern Crusades and the Swedish part-colonisation of coastal Finland, a legacy reflected in the prevalence of the Swedish language and its official status. In 1809, Finland was incorporated into the Russian Empire as the autonomous Grand Duchy of Finland.
In 1906, Finland became the first European state to grant all adult citizens the right to vote, the first in the world to give all adult citizens the right to run for public office. Following the 1917 Russian Revolution, Finland declared itself independent. In 1918, the fledgling state was divided by civil war, with the Bolshevik-leaning Red Guard supported by the new Soviet Russia, fighting the White Guard, supported by the German Empire. After a brief attempt to establish a kingdom, the country became a republic. During World War II, the Soviet Union sought to occupy Finland, with Finland losing parts of Karelia, Kuusamo and some islands, but retaining their independence. Finland established an official policy of neutrality; the Finno-Soviet Treaty of 1948 gave the Soviet Union some leverage in Finnish domestic politics during the Cold War era. Finland joined the OECD in 1969, the NATO Partnership for Peace in 1994, the European Union in 1995, the Euro-Atlantic Partnership Council in 1997, the Eurozone at its inception, in 1999.
Finland was a relative latecomer to industrialisation, remaining a agrarian country until the 1950s. After World War II, the Soviet Union demanded war reparations from Finland not only in money but in material, such as ships and machinery; this forced Finland to industrialise. It developed an advanced economy while building an extensive welfare state based on the Nordic model, resulting in widespread prosperity and one of the highest per capita incomes in the world. Finland is a top performer in numerous metrics of national performance, including education, economic competitiveness, civil liberties, quality of life, human development. In 2015, Finland was ranked first in the World Human Capital and the Press Freedom Index and as the most stable country in the world during 2011–2016 in the Fragile States Index, second in the Global Gender Gap Report, it ranked first on the World Happiness Report report for 2018 and 2019. A large majority of Finns are members of the Evangelical Lutheran Church, freedom of religion is guaranteed under the Finnish Constitution.
The earliest written appearance of the name Finland is thought to be on three runestones. Two have the inscription finlonti; the third was found in Gotland. It dates back to the 13th century; the name can be assumed to be related to the tribe name Finns, mentioned at first known time AD 98. The name Suomi has uncertain origins, but a candidate for a source is the Proto-Baltic word *źemē, meaning "land". In addition to the close relatives of Finnish, this name is used in the Baltic languages Latvian and Lithuanian. Alternatively, the Indo-European word * gʰm-on "man" has been suggested; the word referred only to the province of Finland Proper, to the northern coast of Gulf of Finland, with northern regions such as Ostrobothnia still sometimes being excluded until later. Earlier theories suggested derivation from suomaa or suoniemi, but these are now considered outdated; some have suggested common etymology with saame and Häme, but that theory is uncertain
Tennessee is a state located in the southeastern region of the United States. Tennessee is the 16th most populous of the 50 United States. Tennessee is bordered by Kentucky to the north, Virginia to the northeast, North Carolina to the east, Georgia and Mississippi to the south, Arkansas to the west, Missouri to the northwest; the Appalachian Mountains dominate the eastern part of the state, the Mississippi River forms the state's western border. Nashville is the state's capital and largest city, with a 2017 population of 667,560. Tennessee's second largest city is Memphis, which had a population of 652,236 in 2017; the state of Tennessee is rooted in the Watauga Association, a 1772 frontier pact regarded as the first constitutional government west of the Appalachians. What is now Tennessee was part of North Carolina, part of the Southwest Territory. Tennessee was admitted to the Union as the 16th state on June 1, 1796. Tennessee was the last state to leave the Union and join the Confederacy at the outbreak of the American Civil War in 1861.
Occupied by Union forces from 1862, it was the first state to be readmitted to the Union at the end of the war. Tennessee furnished more soldiers for the Confederate Army than any other state besides Virginia, more soldiers for the Union Army than the rest of the Confederacy combined. Beginning during Reconstruction, it had competitive party politics, but a Democratic takeover in the late 1880s resulted in passage of disenfranchisement laws that excluded most blacks and many poor whites from voting; this reduced competition in politics in the state until after passage of civil rights legislation in the mid-20th century. In the 20th century, Tennessee transitioned from an agrarian economy to a more diversified economy, aided by massive federal investment in the Tennessee Valley Authority and, in the early 1940s, the city of Oak Ridge; this city was established to house the Manhattan Project's uranium enrichment facilities, helping to build the world's first atomic bombs, two of which were dropped on Imperial Japan near the end of World War II.
Tennessee's major industries include agriculture and tourism. Poultry and cattle are the state's primary agricultural products, major manufacturing exports include chemicals, transportation equipment, electrical equipment; the Great Smoky Mountains National Park, the nation's most visited national park, is headquartered in the eastern part of the state, a section of the Appalachian Trail follows the Tennessee-North Carolina border. Other major tourist attractions include the Tennessee Aquarium in Chattanooga; the earliest variant of the name that became Tennessee was recorded by Captain Juan Pardo, the Spanish explorer, when he and his men passed through an American Indian village named "Tanasqui" in 1567 while traveling inland from South Carolina. In the early 18th century, British traders encountered a Cherokee town named Tanasi in present-day Monroe County, Tennessee; the town was located on a river of the same name, appears on maps as early as 1725. It is not known whether this was the same town as the one encountered by Juan Pardo, although recent research suggests that Pardo's "Tanasqui" was located at the confluence of the Pigeon River and the French Broad River, near modern Newport.
The meaning and origin of the word are uncertain. Some accounts suggest, it has been said to mean "meeting place", "winding river", or "river of the great bend". According to ethnographer James Mooney, the name "can not be analyzed" and its meaning is lost; the modern spelling, Tennessee, is attributed to James Glen, the governor of South Carolina, who used this spelling in his official correspondence during the 1750s. The spelling was popularized by the publication of Henry Timberlake's "Draught of the Cherokee Country" in 1765. In 1788, North Carolina created "Tennessee County", the third county to be established in what is now Middle Tennessee; when a constitutional convention met in 1796 to organize a new state out of the Southwest Territory, it adopted "Tennessee" as the name of the state. Tennessee is known as The Volunteer State, a nickname some claimed was earned during the War of 1812 because of the prominent role played by volunteer soldiers from Tennessee during the Battle of New Orleans.
Other sources differ on the origin of the state nickname. This explanation is more because President Polk's call for 2,600 nationwide volunteers at the beginning of the Mexican–American War resulted in 30,000 volunteers from Tennessee alone in response to the death of Davy Crockett and appeals by former Tennessee Governor and Texas politician, Sam Houston. Tennessee borders eight other states: Virginia to the north. Tennessee is tied with Missouri as the state bordering the most other states; the state is trisected by the Tennessee River. The highest point in the state is Clingmans Dome at 6,643 feet (