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abdul kalam

2010-05-21T13:16:00.000-07:00

abdul kalam
Nacimiento 15 de octubre de 1931

Dhanushkodi, en Rameswaram, Tamil Nadu, India

Partido No está afiliado a ningún partido político

Cónyuge Soltero

Religión Islam

Avul Pakir Jainulabdeen Abdul Kalam (Tamil: அவுல் பகிர் ஜைனுலாப்தீன் அப்துல் கலாம் (avul pakir jaiṉulāpkīṉ aptul kalam), Hindi: अवुल पकिर जैनुलअाबदीन अब्दुल कलाम), nació el 15 de octubre, de 1931, en Tamil Nadu, India, usualmente llamado Dr. A.P.J. Abdul Kalam ^) es un ex-Presidente de la India. Un científico e ingeniero destacado, es llamado el Hombre misil de la India por su trabajo y es considerado un líder progresista, mentor, innovador y visionario.

Carrera [editar]Estudió ingeniería aeronáutica en el Instituto de Tecnología de Madrás graduándose en 1958. Luego de su graduación se incorpora a la Organización India de Investigación y Desarrollo para la Defensa (Defence Research and Development Organisation- DRDO) para trabajar en un proyecto de hovercraft. En 1962, Kalam se desplaza a la Agencia India para la Investigación del Espacio (Indian Space Research Organisation - ISRO), donde su equipo lleva a cabo en forma exitosa el lanzamiento de varios satélites. Tuvo un rol destacado como Director de Proyecto en el desarrollo del primer vehículo indio de lanzamiento de satélites (SLV-III) el cual puso con éxito el satélite Rohini en una órbita cercana en julio de 1980.

En 1982, Kalam regresa al DRDO como Director, y se concentra en el desarrollo de misiles guiados. Fue responsable por el dearrollo y puesta en operaciones de los misiles AGNI y PRITHVI. Esto le valió el mote de "El hombre de los misiles de la India". También colaboró en el desarrollo de productos del área de salud utilizando la tecnología desarrollada para los misiles.

En julio de 1992, Kalam se convierte en asesor científico del Ministro de Defensa de India. Como el principal asesor científico al gobierno indio, tiene rango de Ministro de Gabinete. Su trabajo condujo al ensayo nuclear exitoso llamado Pokhran-II en 1998, que confirmó nuevamente la posición de India dentro de la lista de países con armamento nuclear. Kalam fue también el jefe del comite asesor científico al Gabiente (SAC-C) y llevó adelante la iniciativa India Millennium Mission 2020.

Kalam luego se volcó al ámbito académico, ejerciendo como profesor de la cátedra de Tecnología y Transformación de la Sociedad en la Universidad Anna, Chennai desde noviembre de 2001 participando en actividades de docencia e investigación. Pero por sobre todo, comenzó una cruzada para encender las mentes de los jóvenes con el ideal del desarrollo nacional, para ello realizó múltiples encuentros con jóvenes escolares en diversas partes de la India.

Kalam fue electo como Presidente número 11 de la India y tomo posesión del cargo el 25 de julio de 2002.

Distinciones [editar]Kalam tiene la particular distinción de haber recibido doctorados honoríficos de por lo menos treinta universidades, como también las tres condecoraciones de mayor prestigio de la India para civiles: la Padma Bhushan en 1981; la Padma Vibhushan en 1990; y la Bharat Ratna en 1997. Recientemente rechazó un doctorado honorario de una universidad, alegando que ya se siente satisfecho con los que ya ha recibido con su trabajo arduo y determinación. Además es reconocido por haber recibido la medalla del rey Carlos II de la Royal Society, por su permanente colaboración a la difusión de la ciencia en la población India.[1]

Lineamientos políticos [editar]Es posible asomarse a las visiones y propuestas de Kalam sobre ciertos temas a través de posiciones que ha expuesto en el pasado. El libro de su autoría "India 2020" promueve con fuerza un plan de acción para convertir a India en una superpotencia del conocimiento y alcanzar el nivel de una nación desarrollada para el año 2020. Kalam impulsa la idea que India debe tomar un rol más destacado en las relaciones internacionales; el considera que su trabajo en el progama indio de armas nucleares es una forma de afirmar el rol de India como una futura superpotencia.

Kalam sigue teniendo un interés activo en desarrollos en los campos de las ciencias y las tecnologías. Ha propuesto un programa de investigación para desarrollar implantes biológicos. El apoya el software de código libre por sobre soluciones propietarias y cree que el uso de software abierto o libre en gran escala hará que más gente pueda gozar de los beneficios de la tecnología de la información.

Identidad [editar]Kalam proviene de la comunidad Marakkar en el sur de la India, esta comunidad habla el idioma tamil.

Kalam posee una visión modernista, cree en el poder de la tecnología para resolver los problemas de la sociedad y su visión es que estos problemas son la consecuencia de una distribución ineficiente de la riqueza. Ve a la ciencia y a la tecnología como áreas libres de ideologías y enfatiza el desarrollo de carácter o temperamento científico y el espíritu emprendedor. En este sentido, encuentra mucho apoyo entre los nuevos líderes de negocios de la India como los fundadores de Infosys y Wipro quienes comenzaron sus carreras como profesionales de la tecnología en forma similar a Kalam.

11º Presidente de la India

25 de julio de 2002 – 25 de julio de 2007

Vicepresidente Bhairon Singh Shekhawat

Precedido por K. R. Narayanan

Sucedido por Pratibha Patil

Nelson Mandela

2010-05-21T12:46:00.000-07:00

President of South Africa
In office 10 May 1994 – 14 June 1999
Deputy	Thabo Mbeki Frederik Willem de Klerk
Preceded by	Frederik Willem de Klerk As State President of South Africa
Succeeded by	Thabo Mbeki


Secretary General of Non-Aligned Movement
In office 3 September 1998 – 14 June 1999
Preceded by	Andrés Pastrana Arango
Succeeded by	Thabo Mbeki

Born	18 July 1918 (1918-07-18) (age 91) Mvezo, Union of South Africa
Birth name	Rolihlahla Mandela
Political party	African National Congress
Spouse(s)	Evelyn Ntoko Mase (1944–1957) Winnie Madikizela (1957–1996) Graça Machel (1998–present)
Residence	Houghton Estate, South Africa
Alma mater	University of Fort Hare University of London External System University of South Africa University of the Witwatersrand
Religion	Methodism^{[citation needed]}

Signature

Nelson Rolihlahla Mandela (Xhosa pronunciation: [xoˈliɬaɬa manˈdeːla];), born 18 July 1918,^[1] served as President of South Africa from 1994 to 1999, and was the first South African president to be elected in a fully representative democratic election. Before his presidency, Mandela was an anti-apartheid activist, and the leader of Umkhonto we Sizwe, the armed wing of the African National Congress (ANC). The South African courts convicted him on charges of sabotage, as well as other alleged crimes committed while he led the movement against apartheid. In accordance with his sentence, Mandela served 27 years in prison, spending many of these years on Robben Island. Following his release from prison on 11 February 1990, Mandela supported reconciliation and negotiation, and helped lead the transition towards multi-racial democracy in South Africa.
Since the end of apartheid, many have frequently praised Mandela, including former opponents. In South Africa he is often known as Madiba, an honorary title adopted by elders of Mandela's clan. The title has come to be synonymous with Nelson Mandela.
Mandela has received more than 250 awards over four decades, most notably the 1993 Nobel Peace Prize. In November 2009, the United Nations General Assembly announced that Mandela's birthday, 18 July, is to be known as 'Mandela Day' to mark his contribution to world freedom.^[2]

Early life

Nelson Mandela belongs to a cadet branch of the Thembu dynasty, which reigns in the Transkeian Territories of South Africa's Cape Province.^[3] He was born in Mvezo, a small village located in the district of Umtata, the Transkei capital.^[3] His patrilineal great-grandfather Ngubengcuka (who died in 1832), ruled as the Inkosi Enkhulu, or king, of the Thembu people.^[4] One of the king's sons, named Mandela, became Nelson's grandfather and the source of his surname. However, because he was only the Inkosi's child by a wife of the Ixhiba clan (the so-called "Left-Hand House"^[5]), the descendants of his branch of the royal family were not eligible to succeed to the Thembu throne.
Mandela's father, Gadla Henry Mphakanyiswa, served as chief of the town of Mvezo.^[6] However, upon alienating the colonial authorities, they deprived Mphakanyiswa of his position, and moved his family to Qunu. Despite this, Mphakanyiswa remained a member of the Inkosi's Privy Council, and served an instrumental role in Jongintaba Dalindyebo's ascension to the Thembu throne. Dalindyebo would later return the favour by informally adopting Mandela upon Mphakanyiswa's death.^[7] Mandela's father had four wives,^[7] with whom he fathered a total of thirteen children (four boys and nine girls).^[7] Mandela was born to his third wife ('third' by a complex royal ranking system), Nosekeni Fanny. Fanny was a daughter of Nkedama of the Mpemvu Xhosa clan, the dynastic Right Hand House, in whose umzi or homestead Mandela spent much of his childhood.^[8] His given name Rolihlahla means "to pull a branch of a tree", or more colloquially, "troublemaker".^[9]^[10]
Rolihlahla Mandela became the first member of his family to attend a school, where his teacher Miss Mdingane gave him the English name "Nelson".^[11]

Nelson Mandela circa 1937^[12]

When Mandela was nine, his father died of tuberculosis,^[7] and the regent, Jongintaba, became his guardian.^[7] Mandela attended a Wesleyan mission school located next to the palace of the regent. Following Thembu custom, he was initiated at age sixteen, and attended Clarkebury Boarding Institute.^[13] Mandela completed his Junior Certificate in two years, instead of the usual three.^[13] Designated to inherit his father's position as a privy councillor, in 1937 Mandela moved to Healdtown, the Wesleyan college in Fort Beaufort which most Thembu royalty attended.^[14] At nineteen, he took an interest in boxing and running at the school.^[8]
After enrolling, Mandela began to study for a Bachelor of Arts at the Fort Hare University, where he met Oliver Tambo. Tambo and Mandela became lifelong friends and colleagues. Mandela also became close friends with his kinsman, Kaiser ("K.D.") Matanzima who, as royal scion of the Thembu Right Hand House, was in line for the throne of Transkei^[5], a role that would later lead him to embrace Bantustan policies. His support of these policies would place him and Mandela on opposing political sides.^[8] At the end of Nelson's first year, he became involved in a Students' Representative Council boycott against university policies, and was told to leave Fort Hare and not return unless he accepted election to the SRC.^[15] Later in his life, while in prison, Mandela studied for a Bachelor of Laws from the University of London External Programme.
Shortly after leaving Fort Hare, Jongintaba announced to Mandela and Justice (the regent's son and heir to the throne) that he had arranged marriages for both of them. The young men, displeased by the arrangement, elected to relocate to Johannesburg.^[16] Upon his arrival, Mandela initially found employment as a guard at a mine.^[17] However, the employer quickly terminated Mandela after learning that he was the Regent's runaway ward. Mandela later started work as an articled clerk at a Johannesburg law firm, Witkin, Sidelsky and Edelman, through connections with his friend and mentor, realtor Walter Sisulu.^[17] While working at Witkin, Sidelsky and Edelman, Mandela completed his B.A. degree at the University of South Africa via correspondence, after which he began law studies at the University of Witwatersrand, where he first befriended fellow students and future anti-apartheid political activists Joe Slovo, Harry Schwarz and Ruth First. Slovo would eventually become Mandela's Minister of Housing, while Schwarz would become his Ambassador to Washington. During this time, Mandela lived in Alexandra township, north of Johannesburg.^[18]

Thileepan

2010-05-21T12:40:00.000-07:00

Rasaiah Parthipan
Born	November 27, 1960(1960-11-27) Jaffna, Sri Lanka
Died	September 26, 1987 (aged 26) Jaffna, Sri Lanka
Nationality	Sri Lankan
Other names	Thileepan
Occupation	Tamil Militant

Personnel life His real name was Rasaiah Parthipan and was born in Jaffna, Sri Lanka. His father Rasaiah was a school teacher. His mother died during his childhood and he was brought up by his single father. He was a popular student in Jaffna Hindu College, a prominent high school in Jaffna, before joining the LTTE. prior to the 1983 Black July pogrom. [edit] LTTE Rasaiah Parthipan joined the Liberation Tigers of Tamil Eelam in 1983 prior to Black July pogrom. He was given the name Thileepan. He became the LTTE political wing leader of the Jaffna peninsula. He was a determined person making him fast till death. [edit] Reasons for fast "I am confident that our people will, one day, achieve their freedom. It gives me great satisfaction and contentment that I am fulfilling a national responsibility to the nation." On the 15th of September 1987 at 9.30 a.m at the Nallur Murugan Temple, Thileepan began his fast. His main objective was to bring awareness and action to a list of public demands made by himself and the Tamil Tigers, at a time when the relationship between the LTTE and the IPKF administration was deteriorating.^[3] The publicly stated goals of his fast were ^[4] All Tamils detained under the Prevention of Terrorism Act should be released. The colonisation of Sinhalese in Tamil areas under the guise of rehabilitation should be stopped. All such rehabilitation should be stopped until an interim government is formed. The Sri Lankan government should stop opening new Police stations and camps in the Northeastern province. The Sri Lankan Army and Police should withdraw from schools in Tamil villages and the weapons given by the Sri Lankan government to 'homeguards' should be withdrawn under the supervision of the Indian army. [edit] Death Although several groups requested Thileepan as well as the local IPKF administration to intervene and stop the fast, Thileepan died on the 26th of September 1987. There was widespread grief in Tamil areas. Thousands of people from the North and East flooded Jaffna as news of his death spread^{[citation needed]}. His death created an anti-Indian mood in Jaffna that was pro-India till then.^[5] [edit] Resumption of hostilities Several days later the LTTE began hostilities against the Indian Peace Keeping Force. The death of Thileepan was hence seen as a pivotal moment in Sri Lankan History and Sri Lankan - Indian relations for years to come^{[citation needed]}.

shark

2010-05-21T12:33:00.000-07:00

Shark

Fossil range: Silurian–Recent

PreЄЄOSDCPTJKPgN

Grey reef shark (Carcharhinus amblyrhynchos)

Scientific classification

Kingdom: Animalia

Phylum: Chordata

Class: Chondrichthyes

Subclass: Elasmobranchii

Superorder: Selachimorpha

Orders

Carcharhiniformes

Heterodontiformes

Hexanchiformes

Lamniformes

Orectolobiformes

Pristiophoriformes

Squaliformes

Squatiniformes

† Symmoriida

† Cladoselachiformes

† Xenacanthida (Xenacantiformes)

† Eugeneodontida

† Hybodontiformes

Sharks (superorder Selachimorpha) are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago, before the time of the dinosaurs.[1]

Since that time, sharks have diversified into 440 species, ranging in size from the small dwarf lanternshark, Etmopterus perryi, a deep sea species of only 17 centimetres (6.7 in) in length, to the whale shark, Rhincodon typus, the largest fish, which reaches approximately 12 metres (39 ft 4 in) and which feeds only on plankton, squid, and small fish through filter feeding. Sharks are found in all seas and are common down to depths of 2,000 metres (6,562 ft). They generally do not live in freshwater, with a few exceptions such as the bull shark and the river shark which can live both in seawater and freshwater.[2] They respire with the use of five to seven gill slits. Sharks have a covering of dermal denticles that protect their skin from damage and parasites and improve fluid dynamics so the shark can move faster. They have several sets of replaceable teeth.[3]

Well-known species such as the great white shark, Tiger shark, and the hammerhead are apex predators, at the top of the underwater food chain. Their extraordinary skills as predators fascinate and frighten humans, even as their survival is under serious threat from fishing and other human activities.

Until the 16th century,[4] sharks were known to mariners as "sea dogs".[5] According to the OED the name "shark" first came into use after Sir John Hawkins' sailors exhibited one in London in 1569 and used the word to refer to the large sharks of the Caribbean Sea, and later as a general term for all sharks. It has also been suggested to be derived from the Yucatec Maya word for shark, xok, pronounced 'shok'.[6]

Dolphin

2010-05-21T12:28:00.000-07:00

Dolphin

Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacean order, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are among the most intelligent animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture.

Origin of the name

The name is originally from Ancient Greek δελφίς (delphís; "dolphin"), which was related to the Greek δελφύς (delphys; "womb"). The animal's name can therefore be interpreted as meaning "a 'fish' with a womb".[1] The name was transmitted via the Latin delphinus, Middle Latin dolfinus and the Old French daulphin, which reintroduced the ph into the word.

The word is used in a few different ways. It can mean:

Any member of the family Delphinidae (oceanic dolphins),

Any member of the families Delphinidae and Platanistoidea (oceanic and river dolphins),

Any member of the suborder Odontoceti (toothed whales; these include the above families and some others),

Used casually as a synonym for Bottlenose Dolphin, the most common and familiar species of dolphin.

This article uses the second definition and does not describe Porpoises (suborder Odontoceti, family Phocoenidae). Orcas and some closely related species belong to the Delphinidae family and therefore qualify as dolphins, even though they are called whales in common language. A group of dolphins is called a "school" or a "pod". Male dolphins are called "bulls", females "cows" and young dolphins are called "calves

Hybrid dolphins

In 1933, three strange dolphins beached off the Irish coast; they appeared to be hybrids between Risso's and Bottlenose Dolphins.[3] This mating was later repeated in captivity producing a hybrid calf. In captivity, a Bottlenose Dolphin and a Rough-toothed Dolphin produced hybrid offspring.[4] A Common-Bottlenose hybrid lives at SeaWorld California.[5] Other dolphin hybrids live in captivity around the world or have been reported in the wild, such as a Bottlenose-Atlantic Spotted hybrid.[6] The best known hybrid is the Wolphin, a False Killer Whale-Bottlenose Dolphin hybrid. The Wolphin is a fertile hybrid. Two Wolphins currently live at the Sea Life Park in Hawaii; the first was born in 1985 from a male False Killer Whale and a female Bottlenose. Wolphins have also been observed in the wild

Anaconda

2010-05-21T12:03:00.000-07:00

anaconda
Anacondas are large, nonvenomous boas of the genus Eunectes. They are found in tropical South America.

The most familiar species is the green anaconda, "Eunectes murinus", notable for being one of the world's largest snakes. Green anacondas can grow to be 521 cm (17 ft) in length and weighing 97.5 kg (215 lb).[1] They are found east of the Andes in Colombia, Venezuela, the Guianas, Ecuador, Peru, Bolivia, Brazil, and on the island of Trinidad.

Other anacondas are the yellow anaconda, Eunectes notaeus, a smaller species found in eastern Bolivia, southern Brazil, Paraguay and northeastern Argentina; and the dark-spotted anaconda, "Eunectes deschauenseei", a rare species found in northeastern Brazil, coastal French Guiana and Guyana.

All three species are aquatic snakes that prey on other aquatic animals, including fish, river fowl, caiman, and capybaras. Some accounts exist of anacondas preying on domestic animals such as goats and ponies that venture too close to the water.

While encounters between people and anacondas may be dangerous, they do not regularly hunt humans. Nevertheless, threat from anacondas is a familiar trope in comics, movies and adventure stories set in the Amazon jungle. Anacondas have also figured prominently in South American folklore, where they are sometimes depicted as shapeshifting mythical creatures called encantados. Local communities and some European explorers have given accounts of giant anacondas, legendary snakes of much greater proportion than any confirmed specimen.

Applied loosely, the term "anaconda" may also refer to any large snake that "crushes" its prey by constricting.[2]

[edit] Etymology

The Merriam-Webster online dictionary states[3] the word is probably a modification of the Sinhalese word henakandayā,[4][5][6] which is used to refer to a small slender green whip snake found in Sri Lanka. However, certain other literature[7][8] state henakandayā refers to a now extinct constrictor once found there. Richard Boyle (the Sri Lankan English consultant to the Oxford English Dictionary) writes in his book 'Sinbad In Serendib':[9]

The first reference to the anaconda in English is by R. Edwin (probably a pseudonym) in a letter to the Scots magazine concerning an encounter with a tiger-devouring serpent in then Dutch-held Ceylon. This was published in the 1768 issue under the discursive heading, "Description of the ANACONDA, a monstrous species of serpent. In a letter from an English gentleman, many years resident in the island of Ceylon, in the East Indies."[10] However, this account of an incident on the outskirts of Colombo is a figment of the imagination, full of the popular misconceptions regarding constrictors in an age of limited scientific knowledge of snakes.

—Richard Boyle

The Oxford English Dictionary gives a first source as John Ray's "List of Indian Serpents" from the Leyden Museum, as "anacandaia of the Ceylonese, i.e. he that crushes the limbs of buffaloes and yoke beasts," but that "anacandaia" is "not now a native name in Sri Lanka, and not satisfactorily explained either in Cingalese [Sinhalese] or Tamil"—though Henry Yule lists "āṇaik'k'onḍa" to means "having killed an elephant" in Tamil.

dinosaur

2010-05-21T11:50:00.000-07:00

Dinosaur

Dinosaurs are a diverse group of reptiles. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period (about 230 million years ago) until the end of the Cretaceous period (about 65 million years ago), when the Cretaceous–Tertiary extinction event caused the extinction of most dinosaur species, except for some birds. The fossil record indicates that birds evolved from theropod dinosaurs during the Jurassic period, and most paleontologists regard them as the only group of dinosaurs to have survived until the present day.[1]

Dinosaurs are a diverse and varied group of animals; birds, at over 9,000 species, are the most diverse group of vertebrate besides perciform fish.[2] Paleontologists have identified over 500 distinct genera[3] and more than 1,000 different species of non-avian dinosaurs.[4] Dinosaurs are represented on every continent by both extant species and fossil remains.[5] Some dinosaurs are or were herbivorous, others carnivorous. Some have been bipedal, others quadrupedal, and others have been able to shift between these body postures. Many non-avian species developed elaborate skeletal modifications such as bony armor, horns or crests. Avian dinosaurs have been the planet's dominant flying vertebrate since the extinction of the pterosaurs. Although generally known for the large size of some species, most dinosaurs were human-sized or even smaller. Most groups of dinosaurs are known to have built nests and laid eggs.

The term "dinosaur" was coined in 1842 by the English paleontologist Richard Owen, and derives from Greek δεινός (deinos) "terrible, powerful, wondrous" + σαῦρος (sauros) "lizard". Through the first half of the twentieth century, most of the scientific community mistakenly believed dinosaurs to have been sluggish, unintelligent cold-blooded animals. Most research conducted since the 1970s, however, has indicated that dinosaurs were active animals with elevated metabolisms and numerous adaptations for social interaction.

Since the first dinosaur fossils were recognized in the early nineteenth century, mounted dinosaur skeletons have been major attractions at museums around the world, and dinosaurs have become a part of world culture. They have been featured in best-selling books and films such as Jurassic Park, and new discoveries are regularly covered by the media. The outdated image of dinosaurs as maladapted extinct monsters has led to the word "dinosaur" entering the vernacular to describe anything that is impractically large, slow-moving, obsolete, or bound for extinction.[6]

Etymology

The taxon Dinosauria was formally named in 1842 by Sir Richard Owen, who used it to refer to the "distinct tribe or sub-order of Saurian Reptiles" that were then being recognized in England and around the world.[7] The term is derived from the Greek words δεινός (deinos meaning "terrible", "powerful", or "wondrous") and σαῦρος (sauros meaning "lizard" or "reptile").[8] Though the taxonomic name has often been interpreted as a reference to dinosaurs' teeth, claws, and other fearsome characteristics, Owen intended it merely to evoke their size and majesty.[9] In colloquial English "dinosaur" is sometimes used to describe an obsolete or unsuccessful thing or person,[10] despite the dinosaurs' 160 million year reign and the global abundance and diversity of their avian descendants: modern-day birds.

Modern definition

Triceratops skeleton at the American Museum of Natural History in New York CityUnder phylogenetic taxonomy, dinosaurs are usually defined as the group consisting of "Triceratops, Neornithes [modern birds], their most recent common ancestor, and all descendants."[11] It has also been suggested that Dinosauria be defined with respect to the most recent common ancestor of Megalosaurus and Iguanodon, because these were two of the three genera cited by Richard Owen when he recognized the Dinosauria.[12] Both definitions result in the same set of animals being defined as dinosaurs, including theropods (mostly bipedal carnivores), sauropodomorphs (mostly large herbivorous quadrupeds with long necks and tails), ankylosaurians (armored herbivorous quadrupeds), stegosaurians (plated herbivorous quadrupeds), ceratopsians (herbivorous quadrupeds with horns and frills), and ornithopods (bipedal or quadrupedal herbivores including "duck-bills"). These definitions are written to correspond with scientific conceptions of dinosaurs that predate the modern use of phylogenetics. The continuity of meaning is intended to prevent confusion about what the term "dinosaur" means.

There is a wide consensus among paleontologists that birds are the descendants of theropod dinosaurs. Using the strict cladistical definition that all descendants of a single common ancestor must be included in a group for that group to be natural, birds would thus be dinosaurs and dinosaurs are, therefore, not extinct. Birds are classified by most paleontologists as belonging to the subgroup Maniraptora, which are coelurosaurs, which are theropods, which are saurischians, which are dinosaurs.[13]

From the point of view of cladistics, birds are dinosaurs, but in ordinary speech the word "dinosaur" does not include birds. Additionally, referring to dinosaurs that are not birds as "non-avian dinosaurs" is cumbersome. For clarity, this article will use "dinosaur" as a synonym for "non-avian dinosaur". The term "non-avian dinosaur" will be used for emphasis as needed.

General description

Stegosaurus skeleton, Field Museum, ChicagoUsing one of the above definitions, dinosaurs (aside from birds) can be generally described as terrestrial archosaurian reptiles with limbs held erect beneath the body, that existed from the Late Triassic (first appearing in the Carnian faunal stage) to the Late Cretaceous (going extinct at the end of the Maastrichtian).[14] Many prehistoric animals are popularly conceived of as dinosaurs, such as ichthyosaurs, mosasaurs, plesiosaurs, pterosaurs, and Dimetrodon, but are not classified scientifically as dinosaurs. Marine reptiles like ichthyosaurs, mosasaurs, and plesiosaurs were neither terrestrial nor archosaurs; pterosaurs were archosaurs but not terrestrial; and Dimetrodon was a Permian animal more closely related to mammals.[15] Dinosaurs were the dominant terrestrial vertebrates of the Mesozoic, especially the Jurassic and Cretaceous. Other groups of animals were restricted in size and niches; mammals, for example, rarely exceeded the size of a cat, and were generally rodent-sized carnivores of small prey.[16] One notable exception is Repenomamus giganticus, a triconodont weighing between 12 kilograms (26 lb) and 14 kilograms (31 lb) that is known to have eaten small dinosaurs like young Psittacosaurus.[17]

Dinosaurs were an extremely varied group of animals; according to a 2006 study, over 500 dinosaur genera have been identified with certainty so far, and the total number of genera preserved in the fossil record has been estimated at around 1850, nearly 75% of which remain to be discovered.[3] An earlier study predicted that about 3400 dinosaur genera existed, including many which would not have been preserved in the fossil record.[18] As of September 17, 2008, 1047 different species of dinosaurs have been named.[4] Some were herbivorous, others carnivorous. Some dinosaurs were bipeds, some were quadrupeds, and others, such as Ammosaurus and Iguanodon, could walk just as easily on two or four legs. Many had bony armor, or cranial modifications like horns and crests. Although known for large size, many dinosaurs were human-sized or smaller. Dinosaur remains have been found on every continent on Earth, including Antarctica.[5] No dinosaurs are known to have lived in marine or aerial habitats, although it is possible some feathered theropods were flyers. There is also evidence that some spinosaurids had semi-aquatic habits.[19]

Gorilla

2010-05-21T11:41:00.000-07:00

Gorillas[1]

Gorillas are the largest of the living primates. They are ground-dwelling and predominantly herbivorous. They inhabit the forests of central Africa. Gorillas are divided into two species and (still under debate as of 2008) either four or five subspecies. The DNA of gorillas is 98%–99% identical to that of a human,[2] and they are the next closest living relatives to humans after the two chimpanzee species.

Gorillas live in tropical or subtropical forests. Although their range covers a small percentage of Africa, gorillas cover a wide range of elevations. The Mountain Gorilla inhabits the Albertine Rift montane cloud forests of the Virunga Volcanoes, ranging in altitude from 2,200–4,300 metres (7,200–14,100 ft). Lowland Gorillas live in dense forests and lowland swamps and marshes as low as sea level.

Etymology

The American physician and missionary Thomas Staughton Savage and naturalist Jeffries Wyman first described the Western Gorilla (they called it Troglodytes gorilla) in 1847 from specimens obtained in Liberia.[3] The name was derived from the Greek word "Γόριλλαι", (Gorillai), a "tribe of hairy women"[4] described by Hanno the Navigator, a Carthaginian navigator and possible visitor (circa 480 BC) to the area that later became Sierra Leone.[5]

Evolution and classification

Female gorilla.The closest relatives of gorillas are chimpanzees and humans, from which gorillas diverged about 7 million years ago.[6] Human genes differ only 1.6% on average from their corresponding gorilla genes in their sequence, but there is further difference in how many copies each gene has.[7]

Until recently there was considered to be a single gorilla species, with three subspecies: the Western Lowland Gorilla, the Eastern Lowland Gorilla and the Mountain Gorilla.[8][9] There is now agreement that there are two species with two subspecies each. More recently it has been claimed that a third subspecies exists in one of the species.

Primatologists continue to explore the relationships between various gorilla populations.[8] The species and subspecies listed here are the ones upon which most scientists agree.[citation needed]

Genus Gorilla [1]

Western Gorilla (Gorilla gorilla)

Western Lowland Gorilla (Gorilla gorilla gorilla)

Cross River Gorilla (Gorilla gorilla diehli)

Eastern Gorilla (Gorilla beringei)

Mountain Gorilla (Gorilla beringei beringei)

Eastern Lowland Gorilla (Gorilla beringei graueri)

The proposed third subspecies of Gorilla beringei, which has not yet received a trinomen, is the Bwindi population of the Mountain Gorilla, sometimes called the Bwindi Gorilla.

Physical characteristics

Two Western Lowland Gorillas move around at Ueno Zoo.Gorillas move around by knuckle-walking. Adult males range in height from 1.65–1.75 metres (5 ft 5 in–5 ft 9 in), and in weight from 140–200 kg (310–440 lb). Adult females are often half the size of a silverback, averaging about 1.4 metres (4 ft 7 in) tall and 100 kg (220 lb). Occasionally, a silverback of over 1.8 metres (5 ft 11 in) and 230 kg (510 lb) has been recorded in the wild. However, obese gorillas in captivity have reached a weight of 270 kg (600 lb).[10] Gorillas have a facial structure which is described as mandibular prognathism, that is, their mandible protrudes farther out than the maxilla.

The Eastern Gorilla is more darkly colored than the Western Gorilla, with the Mountain Gorilla being the darkest of all. The Mountain Gorilla also has the thickest hair. The Western Lowland Gorilla can be brown or grayish with a reddish forehead. In addition, gorillas that live in lowland forests are more slender and agile than the more bulky Mountain Gorilla.[11]

Almost all gorillas share the same blood type (B)[12] and, like humans, have individual finger prints.[13]

Behavior

Group life

"Blackback" redirects here. For other uses, see Blackback (disambiguation).

"Silverback" redirects here. For other uses, see Silverback (disambiguation).

A silverback is an adult male gorilla, typically more than 12 years of age and named for the distinctive patch of silver hair on his back. A silverback gorilla has large canine teeth that come with maturity. Blackbacks are sexually mature males of up to 11 years of age.

A silverback gorilla portrait.Silverbacks are the strong, dominant troop leaders. Each typically leads a troop (group size ranges from 5 to 30) and is in the center of the troop's attention, making all the decisions, mediating conflicts, determining the movements of the group, leading the others to feeding sites and taking responsibility for the safety and well-being of the troop. Blackbacks may serve as backup protection.

Males will slowly begin to leave their original troop when they are about 11 years old, traveling alone or with a group of other males for 2–5 years before being able to attract females to form a new group and start breeding. While infant gorillas normally stay with their mother for 3–4 years, silverbacks will care for weaned young orphans, though never to the extent of carrying the little gorillas. If challenged by a younger or even by an outsider male, a silverback will scream, beat his chest, break branches, bare his teeth, then charge forward. Sometimes a younger male in the group can take over leadership from an old male. If the leader is killed by disease, accident, fighting or poachers, the group will split up, as the animals disperse to look for a new protective male. Occasionally, a group may be taken over in its entirety by another male. There is a strong risk that the new male will kill the infants of the dead silverback.

Joan of Arc

2010-05-20T13:13:00.000-07:00

name Joan of Arc
Born ca. 1412

Domrémy, France

Died 30 May 1431 (aged 19)

Rouen, France (Then England)

Venerated in Roman Catholic Church

Anglican Communion

Beatified 18 April 1909, Notre Dame de Paris by Pope Pius X

Canonized 16 May 1920, St. Peter's Basilica, Rome by Pope Benedict XV

Feast 30 May

Patronage France ; martyrs; captives; militants; people ridiculed for their piety; prisoners; soldiers; Women Appointed for Voluntary Emergency Service (U.S. WAVES); U.S. Women's Army Corps -

Saint Joan of Arc or The Maid of Orléans (French: Jeanne d'Arc,[1] IPA: [ʒan daʁk]; ca. 1412[2] – 30 May 1431) is a national heroine of France and a Catholic saint. A peasant girl born in eastern France, she led the French army to several important victories during the Hundred Years' War, claiming divine guidance, and was indirectly responsible for the coronation of Charles VII. She was captured by the Burgundians, sold to the English, tried by an ecclesiastical court, and burned at the stake when she was nineteen years old.[3] Twenty-four years later, on the initiative of Charles VII, Pope Callixtus III reviewed the decision of the ecclesiastical court, found her innocent, and declared her a martyr.[3] She was beatified in 1909 and canonized in 1920.[2] She is, along with St. Denis, St. Martin of Tours, St. Louis IX, and St. Theresa of Lisieux, one of the patron saints of France.

Joan asserted that she had visions from God that told her to recover her homeland from English domination late in the Hundred Years' War. The uncrowned King Charles VII sent her to the siege at Orléans as part of a relief mission. She gained prominence when she overcame the dismissive attitude of veteran commanders and lifted the siege in only nine days. Several more swift victories led to Charles VII's coronation at Reims and settled the disputed succession to the throne.

Joan of Arc has remained an important figure in Western culture. From Napoleon to the present, French politicians of all leanings have invoked her memory. Major writers and composers who have created works about her include Shakespeare (Henry VI, Part 1), Voltaire (La Pucelle d'Orléans), Schiller (Die Jungfrau von Orléans ), Verdi (Giovanna d'Arco), Tchaikovsky (Орлеанская дева), Mark Twain (Personal Recollections of Joan of Arc), Jean Anouilh (L'Alouette), Bertolt Brecht (Die heilige Johanna der Schlachthöfe), George Bernard Shaw (Saint Joan), and Maxwell Anderson (Joan of Lorraine). Depictions of her continue in film, television, video games, song, and dance.

Background

France at the outset of Joan of Arc's career. The dot that represents Paris is near the centre of the Anglo-Burgundian-controlled region. Reims lies to the northeast of this area.The historian Kelly DeVries describes the period preceding her appearance with, "If anything could have discouraged her, the state of France in 1429 should have." The Hundred Years' War had begun in 1337 as a succession dispute to the French throne with intermittent periods of relative peace. Nearly all the fighting had taken place in France, and the English use of chevauchée (similar to scorched earth) tactics had devastated the economy. The French population had not recovered from the Black Death of the previous century and its merchants were cut off from foreign markets. At the outset of her career, the English had almost achieved their goal of a dual monarchy under English control and the French army had won no major victory for a generation. In DeVries's words, "the kingdom of France was not even a shadow of its thirteenth-century prototype."[4]

The French king at the time of Joan's birth, Charles VI, suffered bouts of insanity[5] and was often unable to rule. The king's brother Duke Louis of Orléans and the king's cousin John the Fearless, Duke of Burgundy, quarreled over the regency of France and the guardianship of the royal children. This dispute escalated to accusations of an extramarital affair with Queen Isabeau of Bavaria and the kidnappings of the royal children. The matter climaxed with the assassination of the Duke of Orléans in 1407, on the Duke of Burgundy's orders.[6]

The factions loyal to these two men became known as the Armagnacs and the Burgundians. The English king, Henry V, took advantage of this turmoil to invade France, winning a dramatic victory at Agincourt in 1415, and capturing northern French towns.[7] The future French king, Charles VII, assumed the title of Dauphin as heir to the throne at the age of fourteen, after all four of his older brothers died.[8] His first significant official act was to conclude a peace treaty with Burgundy in 1419. This ended in disaster when Armagnac partisans murdered John the Fearless during a meeting under Charles's guarantee of protection. The new duke of Burgundy, Philip the Good, blamed Charles and entered into an alliance with the English. Large sections of France were conquered.[9]

In 1420, Queen Isabeau of Bavaria concluded the Treaty of Troyes, which granted the French royal succession to Henry V and his heirs in preference to her son Charles. This agreement revived rumours about her supposed affair with the late duke of Orléans and raised fresh suspicions that the Dauphin was a royal bastard rather than the son of the king.[10] Henry V and Charles VI died within two months of each other in 1422, leaving an infant, Henry VI of England, the nominal monarch of both kingdoms. Henry V's brother, John of Lancaster, 1st Duke of Bedford, acted as regent.[11]

By the beginning of 1429, nearly all of northern France and some parts of the southwest were under foreign control. The English ruled Paris, while the Burgundians controlled Reims. The latter city was important as the traditional site of French coronations and consecrations, especially since neither claimant to the throne of France had yet been crowned. The English had laid siege to Orléans, which was the only remaining loyal French city north of the Loire. Its strategic location along the river made it the last obstacle to an assault on the remainder of the French heartland. In the words of one modern historian, "On the fate of Orléans hung that of the entire kingdom."[12] No one was optimistic that the city could long withstand the siege.[13]

Life

Further information: Name of Joan of Arc

Her birthplace is now a museum. The village church where she attended Mass is on the right behind the trees.Joan was the daughter of Jacques d'Arc and Isabelle Romée[14] in Domrémy, a village which was then in the duchy of Bar (later annexed to the province of Lorraine and renamed Domrémy-la-Pucelle).[15] Her parents owned about 50 acres (0.2 square kilometres) of land and her father supplemented his farming work with a minor position as a village official, collecting taxes and heading the local watch.[16] They lived in an isolated patch of north-eastern territory that remained loyal to the French crown despite being surrounded by Burgundian lands. Several local raids occurred during her childhood and on one occasion her village was burned.

Joan said she was about nineteen at her trial, so she was born about 1412; she later testified that she experienced her first vision around 1424 at the age of twelve years, when she was out alone in a field and heard voices. She said she cried when they left, as they were so beautiful. She said Saint Michael, Saint Catherine, and Saint Margaret told her to drive out the English and bring the Dauphin to Reims for his coronation.[17]

At the age of sixteen, she asked a kinsman, Durand Lassois, to bring her to nearby Vaucouleurs where she petitioned the garrison commander, Count Robert de Baudricourt, for permission to visit the royal French court at Chinon. Baudricourt's sarcastic response did not deter her.[18] She returned the following January and gained support from two men of standing: Jean de Metz and Bertrand de Poulengy.[19] Under their auspices, she gained a second interview where she made a remarkable prediction about a military reversal near Orléans.[20]

Rise

Ruin of the great hall at Chinon where she met King Charles VII. The castle's only remaining intact tower has also become a museum dedicated to her.Robert de Baudricourt granted her an escort to visit Chinon after news from the front confirmed her prediction. She made the journey through hostile Burgundian territory in male disguise.[21] Upon arriving at the royal court she impressed Charles VII during a private conference. During this time Charles's mother-in-law Yolande of Aragon was financing a relief expedition to Orléans. Joan petitioned for permission to travel with the army and wear the equipment of a knight. She depended on donated items for her armor, horse, sword, banner, and entourage. Her armor was said to be white. Historian Stephen W. Richey explains her attraction as the only source of hope for a regime that was near collapse:

“ After years of one humiliating defeat after another, both the military and civil leadership of France were demoralized and discredited. When the Dauphin Charles granted Joan’s urgent request to be equipped for war and placed at the head of his army, his decision must have been based in large part on the knowledge that every orthodox, every rational, option had been tried and had failed. Only a regime in the final straits of desperation would pay any heed to an illiterate farm girl who claimed that the voice of God was instructing her to take charge of her country’s army and lead it to victory.[22] ”

"King of England, and you, Duke of Bedford, who call yourself regent of the kingdom of France...settle your debt to the king of Heaven; return to the Maiden, who is envoy of the king of Heaven, the keys to all the good towns you took and violated in France."

Her Letter to the English, March–April 1429; Quicherat I, p. 240, trans. Wikipedia.

With Joan's arrival, she effectively turned the long standing Anglo-French conflict into a religious war.[23] But this was not without its risks. Charles' advisers were worried that unless Joan's orthodoxy could be established beyond doubt, that she was not a heretic or a sorceress, Charles' enemies could easily make the claim that his kingdom was a gift from the Devil. To circumvent this possibility, the Dauphin ordered background inquiries and a theological examination at Poitiers to verify her morality. In April 1429, the commission of inquiry "declared her to be of irreproachable life, a good Christian, possessed of the virtues of humility, honesty and simplicity."[23] The theologians at Poitiers did not pass judgement on her divine inspiration; rather, they informed the Dauphin that there was a 'favourable presumption' to be made on the divine nature of her mission. This was enough for Charles, but they put the ball back in his court by stating that he had an obligation to put Joan to the test. 'To doubt or abandon her without suspicion of evil would be to repudiate the Holy Spirit and to become unworthy of God's aid', they declared.[24] The test for the truth of her claims would be the raising of the siege of Orléans.

She arrived at the siege of Orléans on 29 April 1429, but Jean d'Orléans, the acting head of the Orléans ducal family, initially excluded her from war councils and failed to inform her when the army engaged the enemy.[25] This did not prevent her from being present at most councils and battles. The extent of her actual military leadership is a subject of historical debate. Traditional historians such as Édouard Perroy conclude that she was a standard bearer whose primary effect was on morale.[26] This type of analysis usually relies on the condemnation trial testimony, where she stated that she preferred her standard to her sword. Recent scholarship that focuses on the nullification trial testimony asserts that her fellow officers esteemed her as a skilled tactician and a successful strategist. Stephen W. Richey's opinion is one example: "She proceeded to lead the army in an astounding series of victories that reversed the tide of the war enjoyed remarkable success during her brief career-

kangaroo

2010-05-20T13:02:00.000-07:00

kangaroo

A kangaroo is a marsupial from the family Macropodidae (macropods, meaning 'large foot'). In common use the term is used to describe the largest species from this family, especially those of the genus Macropus, Red Kangaroo, Antilopine Kangaroo, Eastern Grey Kangaroo and Western Grey Kangaroo.[1] Kangaroos are endemic to the continent of Australia. The smaller macropods are found in Australia and New Guinea.

Larger kangaroos have adapted much better to changes brought to the Australian landscape by humans and though many of their smaller cousins are endangered, they are plentiful. They are not farmed to any extent, but wild kangaroos are shot for meat, sport, and to protect grazing land for sheep and cattle.[2] Although there is some controversy, harvesting kangaroo meat has many environmental and health benefits over sheep or cows grazed for meat.[3]

The kangaroo is a national symbol of Australia: its emblem is used on the Australian coat of arms,[4] on some of its currency,[5] as well as by some of Australia's best known organisations, including Qantas.[6] The kangaroo is important to both Australian culture and the national image and consequently there are numerous popular culture references.

Terminology

The word kangaroo derives from the Guugu Yimidhirr word gangurru, referring to a grey kangaroo.[7] The name was first recorded as "Kangooroo or Kanguru" on 4 August 1770, by Lieutenant (later Captain) James Cook on the banks of the Endeavour River at the site of modern Cooktown, when HM Bark Endeavour was beached for almost seven weeks to repair damage sustained on the Great Barrier Reef.[8] Guugu Yimidhirr is the language of the people of the area.

A common myth about the kangaroo's English name is that 'kangaroo' was a Guugu Yimidhirr phrase for "I don't understand you."[9] According to this legend, Lieutenant Cook and naturalist Sir Joseph Banks were exploring the area when they happened upon the animal. They asked a nearby local what the creatures were called. The local responded "Kangaroo", meaning "I don't understand you", which Cook took to be the name of the creature. The Kangaroo myth was debunked in the 1970s by linguist John B. Haviland in his research with the Guugu Yimidhirr people.[10]

Male kangaroos are called bucks, boomers, jacks, or old men; females are does, flyers, or jills, and the young ones are joeys.[11] The collective noun for kangaroos is a mob, troop, or court. Kangaroos are often colloquially referred to as roos.[12]

Description

A Tasmanian Forester (Eastern Grey) Kangaroo in motion.There are four species that are commonly referred to as kangaroos:

The Red Kangaroo (Macropus rufus) is the largest surviving marsupial anywhere in the world. Fewer in numbers, the Red Kangaroo occupies the arid and semi-arid centre of the continent. A large male can be 2 metres (6 ft 7 in) tall and weigh 90 kg (200 lb).[13]

The Eastern Grey Kangaroo (Macropus giganteus) is less well-known than the red (outside of Australia), but the most often seen, as its range covers the fertile eastern part of the continent.

The Western Grey Kangaroo (Macropus fuliginosus) is slightly smaller again at about 54 kg (119 lb) for a large male. It is found in the southern part of Western Australia, South Australia near the coast, and the Darling River basin.

The Antilopine Kangaroo (Macropus antilopinus) is, essentially, the far-northern equivalent of the Eastern and Western Grey Kangaroos. Like them, it is a creature of the grassy plains and woodlands, and gregarious.

In addition, there are about 50 smaller macropods closely related to the kangaroo in the family Macropodidae.

Red Kangaroo (Macropus rufus)Europeans have long regarded kangaroos as strange animals. Early explorers described them as creatures that had heads like deer (without antlers), stood upright like men, and hopped like frogs. Combined with the two-headed appearance of a mother kangaroo, this led many back home to dismiss them as travellers' tales for quite some time.[citation needed] The first kangaroo to be exhibited in the western world was an example shot by John Gore, an officer on Captain Cook's Endeavour in 1770.[14][15] The animal was shot and its skin and skull transported back to England whereupon it was stuffed (by taxidermists who had never seen the animal before) and displayed to the general public as a curiosity.

Kangaroos have large, powerful hind legs, large feet adapted for leaping, a long muscular tail for balance, and a small head. Like all marsupials, female kangaroos have a pouch called a marsupium in which joeys complete postnatal development.

Behaviour

Kangaroos are the only large animals to use hopping as a means of locomotion. The comfortable hopping speed for Red Kangaroo is about 20-25km/h (13–16 mph), but speeds of up to 70 km/h (44 mph) can be attained, over short distances, while it can sustain a speed of 40 km/h (25 mph) for nearly two kilometres.[16] This fast and energy-efficient method of travel has evolved because of the need to regularly cover large distances in search of food and water, rather than the need to escape predators.[citation needed]

Because of its long feet, it cannot walk correctly. To move at slow speeds, it uses its tail to form a tripod with its two forelimbs. It then raises its hind feet forward, in a form of locomotion called "crawl-walking."[16]

The average life expectancy of a kangaroo is about 4–6 years.[17]

Diet

An Eastern Grey feeding in native grasslandDifferent species of kangaroos have different diets, although all are strict herbivores. The Eastern Grey Kangaroo is predominantly a grazer eating a wide variety of grasses whereas some other species (e.g. the Red Kangaroo) include significant amounts of shrubs in the diet. The smaller species of kangaroos also consume hypogeal fungi. Many species are nocturnal[18] and crepuscular,[19] usually spending the days resting in shade and the cool evenings, nights and mornings moving about and feeding.

Because of its grazing, kangaroos have developed specialized teeth. Its incisors are able to crop grass close to the ground, and its molars chop and grind the grass. Since the two sides of the lower jaw are not joined together, the lower incisors are farther apart, giving the kangaroo a wider bite. The silica in grass is abrasive, so kangaroo molars move forward as they are ground down, and eventually fall out, replaced by new teeth that grow in the back.[16]

Absence of digestive methane release

Despite having a herbivorous diet similar to ruminants such as cattle which release large quantities of methane through exhaling and eructation, kangaroos release virtually none. The hydrogen byproduct of fermentation is instead converted into acetate, which is then used to provide further energy. Scientists are interested in the possibility of transferring the bacteria responsible from kangaroos to cattle, since the greenhouse gas effect of methane is 23 times greater than that of carbon dioxide, per molecule[20].

Predators

Kangaroos have few natural predators. The Thylacine, considered by palaeontologists to have once been a major natural predator of the kangaroo, is now extinct. Other extinct predators included the Marsupial Lion, Megalania and the Wonambi. However, with the arrival of humans in Australia at least 50,000 years ago and the introduction of the dingo about 5,000 years ago, kangaroos have had to adapt. The mere barking of a dog can set a full-grown male boomer into a wild frenzy.[citation needed] Wedge-tailed Eagles and other raptors usually eat kangaroo carrion. Goannas and other carnivorous reptiles also pose a danger to smaller kangaroo species when other food sources are lacking.

Along with dingos and other canids, introduced species like foxes and feral cats also pose a threat to kangaroo populations. Kangaroos and wallabies are adept swimmers, and often flee into waterways if presented with the option. If pursued into the water, a large kangaroo may use its forepaws to hold the predator underwater so as to drown it.[21] Another defensive tactic described by witnesses is catching the attacking dog with the forepaws and disembowelling it with the hind legs.

Penguin

2010-05-20T12:49:00.000-07:00

Penguin
Kingdom: Animalia

Phylum: Chordata
Class: Aves
Infraclass: Neognathae
Order: Sphenisciformes
Sharpe, 1891
Family: Spheniscidae
Bonaparte, 1831

Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica. Highly adapted for life in the water, penguins have countershaded dark and white plumage, and their wings have become flippers. Most penguins feed on krill, fish, squid, and other forms of sealife caught while swimming underwater. They spend about half of their life on land and half in the oceans.

Although all penguin species are native to the southern hemisphere, they are not found only in cold climates, such as Antarctica. In fact, only a few species of penguin live so far south. Several species are found in the temperate zone, and one species, the Galápagos Penguin, lives near the equator.

The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (Eudyptula minor), also known as the Fairy Penguin, which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins, larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2,000 km south of the equator 35 mya, in a climate decidedly warmer than today.

Etymology

The etymology of the word "penguin" is highly disputed. The English word is not apparently of French[1], nor of Breton[2] or Spanish[3] origin (both attributed to the French word pingouin "auk"), but first appears in English or Dutch.[1]

Some dictionaries suggest a derivation from Welsh pen "head" and gwyn "white", including the Oxford English Dictionary[4], the American Heritage Dictionary[5], the Century Dictionary[6] and Merriam-Webster[7], on the basis that the name was originally applied to the great auk, which had white spots in front of its eyes (although its head was black).

An alternative etymology, found in a few English dictionaries, links the word to Latin pinguis "fat", from its perceived appearance. This etymology would be improbable if "penguin" were found to have been originally applied to the great auk, as some sources suggest.[4][6][2]

A third theory states that the word is an alteration of “pen-wing”, with reference to the rudimentary wings of both great auks and penguins. This has been criticised for the unexplained nature of the alteration of the word.[6]

Systematics and evolution

Living species and recent extinctions

Emperor Penguins (Aptenodytes forsteri), the largest living species.

Adelie Penguin (Pygoscelis adeliae) feeding young. Like its relatives, a neatly bi-coloured species with a head marking.

Magellanic Penguins (Spheniscus magellanicus) guarding nest burrow. The closed neck collar denotes this species.

Closeup of Southern Rockhopper Penguin (Eudyptes chrysocome).The number of extant penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Some sources consider the White-flippered Penguin a separate Eudyptula species, while others treat it as a subspecies of the Little Penguin;[8][9] the actual situation seems to be more complicated.[10] Similarly, it is still unclear whether the Royal Penguin is merely a color morph of the Macaroni penguin. The status of the Rockhopper penguins is also unclear.

Updated after Marples (1962), Acosta Hospitaleche (2004), and Ksepka et al. (2006).

Subfamily Spheniscinae – Modern penguins

Aptenodytes – Great penguins

King Penguin, Aptenodytes patagonicus

Emperor Penguin, Aptenodytes forsteri

Pygoscelis – Brush-tailed penguins

Adélie Penguin, Pygoscelis adeliae

Chinstrap Penguin, Pygoscelis antarctica

Gentoo Penguin, Pygoscelis papua

Eudyptula – Little penguins

Little Blue Penguin, Eudyptula minor

Northern Little Penguin, Eudyptula albosignata (provisional)

Spheniscus – Banded penguins

Magellanic Penguin, Spheniscus magellanicus

Humboldt Penguin, Spheniscus humboldti

Galapagos Penguin, Spheniscus mendiculus

African Penguin, Spheniscus demersus

Megadyptes

Yellow-eyed Penguin, Megadyptes antipodes

Waitaha Penguin, Megadyptes waitaha (extinct)

Eudyptes – Crested penguins

Fiordland Penguin, Eudyptes pachyrynchus

Snares Penguin, Eudyptes robustus

Erect-crested Penguin, Eudyptes sclateri

Western Rockhopper Penguin, Eudyptes chrysocome

Eastern Rockhopper Penguin, Eudyptes filholi

Northern Rockhopper Penguin, Eudyptes moseleyi

Royal Penguin, Eudyptes schlegeli (disputed)

Macaroni Penguin, Eudyptes chrysolophus

Chatham Islands Penguin, Eudyptes sp. (extinct)

Fossil genera

Order Sphenisciformes

Basal and unresolved taxa (all fossil)

Waimanu – basal (Middle-Late Paleocene)

Perudyptes (Middle Eocene of Atacama Desert, Peru) – basal?

Spheniscidae gen. et sp. indet. CADIC P 21 (Leticia Middle Eocene of Punta Torcida, Argentina)[11]

Delphinornis (Middle/Late Eocene? – Early Oligocene of Seymour Island, Antarctica) – Palaeeudyptinae, basal, new subfamily 1?

Archaeospheniscus (Middle/Late Eocene – Late Oligocene) – Palaeeudyptinae? New subfamily 2?

Marambiornis (Late Eocene –? Early Oligocene of Seymour Island, Antarctica) – Palaeeudyptinae, basal, new subfamily 1?

Mesetaornis (Late Eocene –? Early Oligocene of Seymour Island, Antarctica) – Palaeeudyptinae, basal, new subfamily 1?

Tonniornis (Late Eocene –? Early Oligocene of Seymour Island, Antarctica)

Wimanornis (Late Eocene –? Early Oligocene of Seymour Island, Antarctica)

Duntroonornis (Late Oligocene of Otago, New Zealand) – possibly Spheniscinae

Korora (Late Oligocene of S Canterbury, New Zealand)

Platydyptes (Late Oligocene of New Zealand) – possibly not monophyletic; Palaeeudyptinae, Paraptenodytinae or new subfamily?

Spheniscidae gen. et sp. indet. (Late Oligocene/Early Miocene of Hakataramea, New Zealand)[verification needed]

Madrynornis (Puerto Madryn Late Miocene of Argentina) – possibly Spheniscinae

Pseudaptenodytes (Late Miocene/Early Pliocene)

Dege (Early Pliocene of South Africa) – possibly Spheniscinae

Marplesornis (Early Pliocene) – possibly Spheniscinae

Nucleornis (Early Pliocene of Duinfontain, South Africa) – possibly Spheniscinae

Inguza (Late Pliocene) – probably Spheniscinae; formerly Spheniscus predemersus

A damaged tarsometatarsus of the prehistoric Narrow-flippered Penguin (Palaeeudyptes antarcticus).Family Spheniscidae

Subfamily Palaeeudyptinae – Giant penguins (fossil)

Crossvallia (Cross Valley Late Paleocene of Seymour Island, Antarctica) – tentatively assigned to this subfamily

Anthropornis (Middle Eocene? – Early Oligocene of Seymour Island, Antarctica) – tentatively assigned to this subfamily

Nordenskjoeld's Giant Penguin, Anthropornis nordenskjoeldi

Icadyptes (Late Eocene of Atacama Desert, Peru)

Palaeeudyptes (Middle/Late Eocene – Late Oligocene) – polyphyletic; some belong in other subfamilies

Pachydyptes (Late Eocene)

Anthropodyptes (Middle Miocene) – tentatively assigned to this subfamily

Subfamily Paraptenodytinae – Stout-footed penguins (fossil)

Arthrodytes (San Julian Late Eocene/Early Oligocene – Patagonia Early Miocene of Patagonia, Argentina)

Paraptenodytes (Early – Late Miocene/Early Pliocene)

Subfamily Palaeospheniscinae – Slender-footed penguins (fossil)

Eretiscus (Patagonia Early Miocene of Patagonia, Argentina)

Palaeospheniscus (Early? – Late Miocene/Early Pliocene) – includes Chubutodyptes

Taxonomy

Some recent sources[12] apply the phylogenetic taxon Spheniscidae to what here is referred to as Spheniscinae. Furthermore, they restrict the phylogenetic taxon Sphenisciformes to flightless taxa, and establish the phylogenetic taxon Pansphenisciformes as equivalent to the Linnean taxon Sphenisciformes,[13] i.e., including any flying basal "proto-penguins" to be discovered eventually. Given that neither the relationships of the penguin subfamilies to each other nor the placement of the penguins in the avian phylogeny is presently resolved, this seems spurious[neutrality is disputed] and in any case is confusing; the established Linnean system is thus followed here.

Evolution

The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography; though as penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. Some seminal articles about penguin prehistory have been published since 2005,[14][15][16][17] the evolution of the living genera can be considered resolved by now.

The basal penguins lived around the time of the Cretaceous–Tertiary extinction event somewhere in the general area of (southern) New Zealand and Byrd Land, Antarctica.[16] Due to plate tectonics, these areas were at that time less than 1,500 kilometers (932 mi) apart rather than the 4,000 kilometers (2,485 mi) of today. The most recent common ancestor of penguins and their sister clade can be roughly dated to the Campanian–Maastrichtian boundary, around 70–68 mya.[15][17][18] What can be said as certainly as possible in the absence of direct (i.e., fossil) evidence is that by the end of the Cretaceous, the penguin lineage must have been evolutionarily well distinct, though much less so morphologically; it is fairly likely that they were not yet entirely flightless at that time, as flightless birds have generally low resilience to the breakdown of trophic webs that follows the initial phase of mass extinctions because of their below-average dispersal capabilities (see also Flightless Cormorant).[citation needed]

The basal fossils

The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya.[17] While they were not as well-adapted to aquatic life as modern penguins, Waimanu were generally loon-like birds but already flightless, with short wings adapted for deep diving.[citation needed] They swam on the surface using mainly their feet, but the wings were – as opposed to most other diving birds, living and extinct – already adapting to underwater locomotion.[citation needed]

Perudyptes from northern Peru was dated to 42 mya. An unnamed fossil from Argentina proves that by the Bartonian (Middle Eocene), some 39–38 mya,[19] primitive penguins had spread to South America and were in the process of expanding into Atlantic waters.[13]

Palaeeudyptines

During the Late Eocene and the Early Oligocene (40–30 mya), some lineages of gigantic penguins existed. Nordenskjoeld's Giant Penguin was the tallest, growing nearly 1.80 meters (6 ft) tall. The New Zealand Giant Penguin was probably the heaviest, weighing 80 kg or more. Both were found on New Zealand, the former also in the Antarctic farther eastwards.

Traditionally, most extinct species of penguins, giant or small, had been placed in the paraphyletic subfamily called Palaeeudyptinae. More recently, with new taxa being discovered and placed in the phylogeny if possible, it is becoming accepted that there were at least two major extinct lineages. One or two closely related ones occurred in Patagonia, and at least one other—which is or includes the paleeudyptines as recognized today – occurred on most Antarctic and subantarctic coasts.

But size plasticity seems to have been great at this initial stage of penguin radiation: on Seymour Island, Antarctica, for example, around 10 known species of penguins ranging in size from medium to huge apparently coexisted some 35 mya during the Priabonian (Late Eocene).[20] It is not even known whether the gigantic palaeeudyptines constitute a monophyletic lineage, or whether gigantism was evolved independently in a much restricted Palaeeudyptinae and the Anthropornithinae – whether they were considered valid, or whether there was a wide size range present in the Palaeeudyptinae as delimited as usually done these days (i.e., including Anthropornis nordenskjoeldi).[16] The oldest well-described giant penguin, the 5-foot-tall Icadyptes salasi, actually occurred as far north as northern Peru about 36 mya.

In any case, the gigantic penguins had disappeared by the end of the Paleogene, around 25 mya. Their decline and disappearance coincided with the spread of the Squalodontoidea and other primitive, fish-eating toothed whales, which certainly competed with them for food, and were ultimately more successful.[15] A new lineage, the Paraptenodytes, which includes smaller but decidedly stout-legged forms, had already arisen in southernmost South America by that time. The early Neogene saw the emergence of yet another morphotype in the same area, the similarly-sized but more gracile Palaeospheniscinae, as well as the radiation that gave rise to the penguin biodiversity of our time.

Origin and systematics of modern penguins

Modern penguins consititute two undisputed clades and another two more basal genera with more ambiguous relationships.[14] The origin of the Spheniscinae lies probably in the latest Paleogene, and geographically it must have been much the same as the general area in which the order evolved: the oceans between the Australia-New Zealand region and the Antarctic.[15] Presumedly diverging from other penguins around 40 mya,[15] it seems that the Spheniscinae were for quite some time limited to their ancestral area, as the well-researched deposits of the Antarctic Peninsula and Patagonia have not yielded Paleogene fossils of the subfamily. Also, the earliest spheniscine lineages are those with the most southern distribution.

The genus Aptenodytes appears to be the basalmost divergence among living penguins [21] [22] they have bright yellow-orange neck, breast, and bill patches; incubate by placing their eggs on their feet, and when they hatch the chicks are almost naked. This genus has a distribution centered on the Antarctic coasts and barely extends to some subantarctic islands today.

Pygoscelis contains species with a fairly simple black-and-white head pattern; their distribution is intermediate, centered on Antarctic coasts but extending somewhat northwards from there. In external morphology, these apparently still resemble the common ancestor of the Spheniscinae, as Aptenodytes' autapomorphies are in most cases fairly pronounced adaptations related to that genus' extreme habitat conditions. As the former genus, Pygoscelis seems to have diverged during the Bartonian,[23] but the range expansion and radiation that led to the present-day diversity probably did not occur until much later; around the Burdigalian stage of the Early Miocene, roughly 20–15 mya.[15]

The genera Spheniscus and Eudyptula contain species with a mostly subantarctic distribution centered on South America; some, however, range quite far northwards. They all lack carotenoid coloration, and the former genus has a conspicuous banded head pattern; they are unique among living penguins by nesting in burrows. This group probably radiated eastwards with the Antarctic Circumpolar Current out of the ancestral range of modern penguins throughout the Chattian (Late Oligocene), starting approximately 28 mya.[15] While the two genera separated during this time, the present-day diversity is the result of a Pliocene radiation, taking place some 4–2 mya.[15]

The Megadyptes–Eudyptes clade occurs at similar latitudes (though not as far north as the Galapagos Penguin), has its highest diversity in the New Zealand region, and represent a westward dispersal. They are characterized by hairy yellow ornamental head feathers; their bills are at least partly red. These two genera diverged apparently in the Middle Miocene (Langhian, roughly 15–14 mya), but again, the living species of Eudyptes are the product of a later radiation, stretching from about the late Tortonian (Late Miocene, 8 mya) to the end of the Pliocene.[15]

The geographical and temporal pattern or spheniscine evolution corresponds closely to two episodes of global cooling documented in the paleoclimatic record.[15] The emergence of the subantarctic lineage at the end of the Bartonian corresponds with the onset of the slow period of cooling that eventually led to the ice ages some 35 million years later. With habitat on the Antarctic coasts declining, by the Priabonian more hospitable conditions for most penguins existed in the subantarctic regions rather than in Antarctica itself[24]. Notably, the cold Antarctic Circumpolar Current also started as a continuous circumpolar flow only around 30 mya, on the one hand forcing the Antarctic cooling, and on the other facilitating the eastward expansion of Spheniscus to South America and eventually beyond.[15] Despite this, there is no fossil evidence to support the idea a crown radiation from the antarctic continent in the Paleogene [25].

Later, an interspersed period of slight warming was ended by the Middle Miocene Climate Transition, a sharp drop in global average temperature from 14–12 mya, and similar abrupt cooling events followed at 8 mya and 4 mya; by the end of the Tortonian, the Antarctic ice sheet was already much like today in volume and extent. The emergence of most of today's subantarctic penguin species almost certainly was caused by this sequence of Neogene climate shifts

Tiger

2010-05-20T12:36:00.000-07:00

tiger

The tiger (Panthera tigris) is a member of the Felidae family and the largest and possibly most dangerous of the four "big cats" in the genus Panthera.[4] Native to much of eastern and southern Asia, the tiger is an apex predator and an obligate carnivore. Reaching up to 3.3 metres (11 ft) in total length, weighing up to 300 kilograms (660 pounds), and having canines up to 4 inches long[5], the larger tiger subspecies are comparable in size to the biggest extinct felids.[6][7] Aside from their great bulk and power, their most recognisable feature is a pattern of dark vertical stripes that overlays near-white to reddish-orange fur, with lighter underparts. The most numerous tiger subspecies is the Bengal tiger while the largest subspecies is the Siberian tiger.

Tigers have a lifespan of 10-15 years in the wild, but can live longer than 20 years in captivity.[8] They are highly adaptable and range from the Siberian taiga, to open grasslands, to tropical mangrove swamps. They are territorial and generally solitary animals, often requiring large contiguous areas of habitat that support their prey demands. This, coupled with the fact that they are indigenous to some of the more densely populated places on earth, has caused significant conflicts with humans. Of the nine subspecies of modern tiger, three are extinct and the remaining six are classified as endangered, some critically so. The primary direct causes are habitat destruction and fragmentation, and hunting. Their historical range once stretched from Mesopotamia and the Caucasus through most of South and East Asia. Today it has been radically reduced. While all surviving species are under formal protection, poaching, habitat destruction and inbreeding depression continue to threaten the species.

Tigers are among the most recognisable and popular of the world's charismatic megafauna. They have featured prominently in ancient mythology and folklore, and continue to be depicted in modern films and literature. Tigers appear on many flags and coats of arms, as mascots for sporting teams, and as the national animal of several Asian nations, including India

Naming and etymology

The word "tiger" is taken from the Greek word "tigris", which is possibly derived from a Persian source meaning "arrow", a reference to the animal's speed and also the origin for the name of the Tigris river.[10][11] In American English, "Tigress" was first recorded in 1611. It was one of the many species originally described, as Felis tigris, by Linnaeus in his 18th century work, Systema Naturae.[3][12] The generic component of its scientific designation, Panthera tigris, is often presumed to derive from Greek pan- ("all") and theron ("beast"), but this may be a folk etymology. Although it came into English through the classical languages, panthera is probably of East Asian origin, meaning "the yellowish animal", or "whitish-yellow".[13]

A group of tigers[14] is rare (see below), but when seen together is termed a "streak" or an "ambush".

2009)

In the past, the tiger's range was widespread in Asia, from the Caucasus and the Caspian Sea to Siberia and Indonesia. During the 19th century, these cats completely vanished from western Asia, and became restricted to isolated pockets in the remaining parts of their range. Today, their range is fragmented, and extends from India in the west to China and Southeast Asia in the east. The northern limit is close to the Amur River in south eastern Siberia. The only large island inhabited by tigers today is Sumatra. Tigers vanished from Java and Bali during the 20th century, and in Borneo are known only from fossil remains.

Tiger habitats will usually include sufficient cover, proximity to water, and an abundance of prey sources. Bengal Tigers live in many types of forests, including wet; evergreen; the semi-evergreen of Assam and eastern Bengal; the mangrove forest of the Ganges Delta; the deciduous forest of Nepal, and the thorn forests of the Western Ghats. Compared to the lion, the tiger prefers denser vegetation, for which its camouflage colouring is ideally suited, and where a single predator is not at a disadvantage compared with the multiple felines in a pride. Among the big cats, only the tiger and jaguar are strong swimmers; tigers are often found bathing in ponds, lakes, and rivers. Unlike other cats, which tend to avoid water, tigers actively seek it out. During the extreme heat of the day, they often cool off in pools. Tigers are excellent swimmers and can swim up to 4 miles. This cat will also carry their dead prey across lakes.

Physical characteristics, taxonomy and evolution

The oldest remains of a tiger-like cat, called Panthera palaeosinensis, have been found in China and Java. This species lived about 2 million years ago, at the beginning of the Pleistocene, and was smaller than a modern tiger. The earliest fossils of true tigers are known from Java, and are between 1.6 and 1.8 million years old. Distinct fossils from the early and middle Pleistocene were also discovered in deposits from China, and Sumatra. A subspecies called the Trinil tiger (Panthera tigris trinilensis) lived about 1.2 million years ago and is known from fossils found at Trinil in Java.[15]

Tigers first reached India and northern Asia in the late Pleistocene, reaching eastern Beringia (but not the American Continent), Japan, and Sakhalin. Fossils found in Japan indicate that the local tigers were, like the surviving island subspecies, smaller than the mainland forms. This may be due to the phenomenon in which body size is related to environmental space (see insular dwarfism), or perhaps the availability of prey. Until the Holocene, tigers also lived in Borneo, as well as on the island of Palawan in the Philippines

Grand Canyon

2010-05-19T12:35:00.000-07:00

grand canyon

Grand Canyon
Grand Canyon

Apollo Throne in sunset light from the South Rim of the Grand Canyon at Moran Point.

Grand CanyonArizona, United States

Floor elevation approx. 2,600 feet (800 m)

Long-axis length 277 miles (446 km)

Width 4 to 18 miles (6.4 to 29 km)

Coordinates 36°06′N 112°06′W / 36.1°N 112.1°W / 36.1; -112.1Coordinates: 36°06′N 112°06′W / 36.1°N 112.1°W / 36.1; -112.1

The Grand Canyon is a steep-sided gorge carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, one of the first national parks in the United States. President Theodore Roosevelt was a major proponent of preservation of the Grand Canyon area, and visited it on numerous occasions to hunt and enjoy the scenery.

The Grand Canyon is 277 miles (446 km) long, ranges in width from 4 to 18 miles (6.4 to 29 km) and attains a depth of over a mile (1.83 km) (6000 feet).[1] Nearly two billion years of the Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted.[2] While the specific geologic processes and timing that formed the Grand Canyon are the subject of debate by geologists,[3] recent evidence suggests the Colorado River established its course through the canyon at least 17 million years ago.[4] Since that time, the Colorado River continued to erode and form the canyon to the point we see it as today.[5]

Before European immigration, the area was inhabited by Native Americans who built settlements within the canyon and its many caves. The Pueblo people considered the Grand Canyon ("Ongtupqa" in Hopi language) a holy site and made pilgrimages to it.[6] The first European known to have viewed the Grand Canyon was García López de Cárdenas from Spain, who arrived in 1540

Geography

A map of the Grand Canyon and surrounding areas, circa 1908.The Grand Canyon is a massive rift in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and is also one of the six distinct physiographic sections of the Colorado Plateau province. It is not the deepest canyon in the world (Kali Gandaki Gorge in Nepal is far deeper), nor the widest (Capertee Valley in Australia is about 1 km wider and longer than Grand Canyon); however, the Grand Canyon is known for its visually overwhelming size and its intricate and colorful landscape. Geologically it is significant because of the thick sequence of ancient rocks that are beautifully preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent.

Temples, Castles, and Shrines.Uplift associated with mountain building events later moved these sediments thousands of feet upward and created the Colorado Plateau. The higher elevation has also resulted in greater precipitation in the Colorado River drainage area, but not enough to change the Grand Canyon area from being semi-arid. The uplift of the Colorado Plateau is uneven, and the north-south trending Kaibab Plateau that Grand Canyon bisects is over a thousand feet higher at the North Rim (about 1,000 ft/300 m) than at the South Rim. Almost all runoff from the North Rim (which also gets more rain and snow) flows toward the Grand Canyon, while much of the runoff on the plateau behind the South Rim flows away from the canyon (following the general tilt). The result is deeper and longer tributary washes and canyons on the north side and shorter and steeper side canyons on the south side.

Temperatures on the North Rim are generally lower than the South Rim because of the greater elevation (averaging 8,000 ft/2,438 m above sea level).[8] Heavy rains are common on both rims during the summer months. Access to the North Rim via the primary route leading to the canyon (State Route 67) is limited during the winter season due to road closures. Views from the North Rim tend to give a better impression of the expanse of the canyon than those from the South Rim.

Geology

Main article: Geology of the Grand Canyon area

Diagram showing the placement, age and thickness of the rock units exposed in the Grand Canyon.The Colorado River basin (of which the Grand Canyon is a part) has developed in the past 40 million years. A recent study places the origins of the canyon beginning some 17 million years ago. Previous estimates had placed the age of the canyon at 5 to 6 million years. The study, which was published in the journal Science in 2008, utilized uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon.[9] There is a substantial amount of controversy because this research suggests such a substantial departure from prior widely supported scientific consensus.[10]

The result of all this erosion is one of the most complete geologic columns on the planet.

The major geologic exposures in the Grand Canyon range in age from the 2 billion year old Vishnu Schist at the bottom of the Inner Gorge to the 230 million year old Kaibab Limestone on the Rim. Interestingly, there is a gap of about one billion years between the stratum that is about 500 million years old and the lower level, which is about 1.5 billion years old. That indicates a period of erosion between two periods of deposition.

Many of the formations were deposited in warm shallow seas, near-shore environments (such as beaches), and swamps as the seashore repeatedly advanced and retreated over the edge of a proto-North America. Major exceptions include the Permian Coconino Sandstone, which most geologists interpret as an aeolian sand dune deposit and several parts of the Supai Group.

The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000 to 10,000 feet (1500 to 3000 m) of uplift of the Colorado Plateau, starting about 65 million years ago (during the Laramide Orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions).

Weather conditions during the ice ages also increased the amount of water in the Colorado River drainage system. The ancestral Colorado River responded by cutting its channel faster and deeper.

The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion.[11]

About one million years ago, volcanic activity (mostly near the western canyon area) deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.

Old City (Jerusalem)

2010-05-19T12:33:00.000-07:00

State Party	No nation named by UNESCO, controlled by Israel since 1967.^[2] Site proposed by Jordan
Type	Cultural
Criteria	ii, iii, vi
Reference	148
Region**	Middle East

History

According to the Bible, before King David's conquest of Jerusalem in the 11th century BCE the city was home to the Jebusites. The Bible describes the city as heavily fortified with a strong city wall. The city ruled by King David, known as Ir David, or the City of David, is now believed to be southwest of the Old City walls, outside the Dung Gate. His son King Solomon extended the city walls and then, in about 440 BCE, in the Persian period, Nehemiah returned from Babylon and rebuilt them. In 41-44 CE, Agrippa, king of Judea, built a new city wall known as the "Third Wall."
Muslims occupied Jerusalem in the 7th Century (637 CE) under the second caliph, Umar Ibn al-Khattab who annexed it to the Islamic Arab Empire. He granted its inhabitants an assurance treaty. After the siege of Jerusalem, Sophronius welcomed `Umar because, according to biblical prophecies allegedly known to the church in Jerusalem, "a poor, but just and powerful man" will rise to be a protector and an ally to the Christians of Jerusalem. Sophronius believed that `Umar, a great warrior who led an austere life, was a fulfillment of this prophecy. In the account by the Patriarch of Alexandria, Eutychius, it is said that `Umar paid a visit to the Church of the Holy Sepulchre and sat in its courtyard. When the time for prayer arrived, however, he left the church and prayed outside the compound, in order to avoid having future generations of Muslims use his prayer there as a pretext for converting the church into a mosque. Eutychius adds that `Umar also wrote a decree which he handed to the Patriarch, in which he prohibited that Muslims gather in prayer at the site.^[8] In 1099 Jerusalem was captured by the Western Christian army of the First Crusade and remained in their hands until recaptured by the Arab Muslims led by Saladin, on October 2, 1187. He summoned the Jews and permitted them to resettle in the city. In 1219 the walls of the city were razed by Mu'azzim Sultan of Damascus; in 1229, by treaty with Egypt, Jerusalem came into the hands of Frederick II of Germany. In 1239 he began to rebuild the walls; but they were again demolished by Da'ud, the emir of Kerak. In 1243 Jerusalem came again under the control of the Christians, and the walls were repaired. The Kharezmian Tatars took the city in 1244 and Sultan Malik al-Muattam razed the city walls, rendering it again defenseless and dealing a heavy blow to the city's status.

Suleiman I 1530

The current walls of the Old City were built in 1538 by the Muslim Ottoman Empire Sultan Suleiman the Magnificent. The walls stretch for approximately 4.5 kilometres, (2.8 miles), and rise to a height of 5–15 metres, (16–49 feet), with a thickness of 3 metres, (10 ft).^[9] Altogether, the Old City walls contain 43 surveillance towers and 11 gates, seven of which are presently open.

[edit] Jerusalem Quarters

Jaffa Gate

The Arab market in the Old City of Jerusalem

[edit] Muslim Quarter

Main article: Muslim Quarter

The Muslim Quarter is the largest and most populous of the four quarters and is situated in the northeastern corner of the Old City, extending from the Lions' Gate in the east, along the northern wall of the Temple Mount in the south, to the Damascus Gate route in the west. Its population was 22,000 in 2005. Like the other three quarters of the Old City, the Muslim quarter had a mixed population of Jews as well as Muslims and Christians until the riots of 1929.^[10] Today 60 Jewish families live in the Muslim Quarter,^{[citation needed]} and a few yeshivot are located there. The main one is Yeshivat Ateret Cohanim.

[edit] Christian Quarter

Main article: Christian Quarter

The Christian Quarter is situated in the northwestern corner of the Old City, extending from the New Gate (see below) in the north, along the western wall of the Old City as far as the Jaffa Gate, along the Jaffa Gate - Western Wall route in the south, bordering on the Jewish and Armenian Quarters, as far as the Damascus Gate in the east, where it borders on the Muslim Quarter. The quarter contains the Church of the Holy Sepulchre, one of Christianity's holiest places.

[edit] Armenian Quarter

Main article: Armenian Quarter

The Armenian Quarter is the smallest of the four quarters of the Old City. Although the Armenian people are Christians, the Armenian Quarter is distinct from the Christian Quarter. Despite the small size and population of this quarter, the Armenians and their Patriarchate remain staunchly independent and form a vigorous presence in the Old City. After the 1948 Arab-Israeli War, the four quarters of the city came under Jordanian control. Jordanian law required Armenians and other Christians to “give equal time to the Bible and Qur'an” in private Christian schools, and restricted the expansion of church assets. The 1967 war is remembered by residents of the quarter as a miracle, after two unexploded bombs were found inside the Armenian monastery. Today more than 3,000 Armenians live in Jerusalem, 500 of them in the Armenian Quarter. Some are temporary residents studying at the seminary or working as church functionaries. The Patriarchate owns the land in this quarter as well as valuable property in West Jerusalem and elsewhere. In 1975, a theological seminary was established in the Armenian Quarter. After the 1967 war, the Israeli government gave compensation for repairing any churches or holy sites damaged in the fighting, regardless of who caused the damage.

Jerusalem
Names History Timeline Sieges Sites Old City Buildings Demographics Mayors Religions Christianity Islam Judaism Transportation Education
v • d • e

[edit] Jewish Quarter

Western Wall and Dome of the Rock

Main article: Jewish Quarter (Jerusalem)

The Jewish Quarter (Hebrew: הרובע היהודי‎, HaRova HaYehudi, known colloquially to residents as HaRova) lies in the southeastern sector of the walled city, and stretches from the Zion Gate in the south, along the Armenian Quarter on the west, up to the Cardo in the north and extends to the Western Wall and the Temple Mount in the east. The quarter has had a rich history, with a nearly continual Jewish presence since the eighth century BCE.^{[citation needed]} In 1948 its population of about 2,000 Jews was besieged, and forced to leave en masse.^[11] The quarter was completely sacked by the Arabs, with ancient synagogues destroyed.
The quarter remained under Jordanian control until its capture by Israeli paratroops in the Six-Day War of 1967. A few days later, Israeli authorities ordered the demolition of the adjacent Moroccan Quarter, expelling all of its inhabitants, in order to facilitate public access to the Western Wall.
The section of the Jewish quarter destroyed prior to 1967 has since been rebuilt and settled, and has a population of 2,348 (as of 2004),^[12] and many large educational institutions have taken up residence. Before being rebuilt, the quarter was carefully excavated under the supervision of Hebrew University archaeologist Nahman Avigad. The archaeological remains, on display in a series of museums and outdoor parks, to visit which tourists descend two or three stories beneath the level of the current city, collectively form one of the world's most accessible archaeological sites. The former Chief Rabbi is Rabbi Avigdor Nebenzahl, and current is his son Rabbi Chizkiyahu Nebenzahl who is on the faculty of Yeshivat Netiv Aryeh situated directly across from the Kotel.

Aurora (astronomy)

2010-05-19T12:29:00.000-07:00

Aurora (astronomy)
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"Aurora Borealis" redirects here. For other uses, see Aurora Borealis (disambiguation).

"Aurora Australis" redirects here. For the ship, see Aurora Australis (icebreaker). For the book, see Aurora Australis (book).

For other uses, see Aurora (disambiguation).

The Aurora Borealis shines above Bear Lake

Red and green Aurora in Fairbanks, Alaska

Aurora australis in Antarctica

Aurora timelapse videoAuroras, also known as northern and southern (polar) lights or aurorae (singular: aurora), are natural light displays in the sky, usually observed at night, particularly in the polar regions. They typically occur in the ionosphere. They are also referred to as polar auroras. This is a misnomer however, because they are commonly visible between 65 to 72 degrees north and south latitudes, which would place it in a ring just within the Arctic and Antarctic circles. Aurorae occur deeper inside the polar regions, but these are infrequent occurrences, and these are often invisible to the naked eye.

In northern latitudes, the effect is known as the aurora borealis, named after the Roman goddess of dawn, Aurora, and the Greek name for north wind, Boreas, by Pierre Gassendi in 1621.[1] The aurora borealis is also called the northern polar lights, as it is only visible in the sky from the Northern Hemisphere, with the chance of visibility increasing with proximity to the North Magnetic Pole. (Earth's is currently in the arctic islands of northern Canada.) Auroras seen near the magnetic pole may be high overhead, but from further away, they illuminate the northern horizon as a greenish glow or sometimes a faint red, as if the sun were rising from an unusual direction. The Aurora Borealis most often occurs near the equinoxes. The northern lights have had a number of names throughout history. The Cree call this phenomenon the "Dance of the Spirits." In the Middle Ages the auroras have been called a sign from God (see Wilfried Schröder, Das Phänomen des Polarlichts, Darmstadt 1984).

Its southern counterpart, the aurora australis or the southern polar lights, has similar properties, but is only visible from high southern latitudes in Antarctica, South America, or Australasia. Australis is the Latin word for "of the South."

Auroras can be spotted throughout the world and on other planets. It is most visible closer to the poles due to the longer periods of darkness and the magnetic field.

Auroral mechanism

Auroras are the result of the emissions of photons in the Earth's upper atmosphere, above 80 km (50 miles), from ionized nitrogen atoms regaining an electron, and oxygen and nitrogen atoms returning from an excited state to ground state. They are ionized or excited by the collision of solar wind particles being funneled down and accelerated along the Earth's magnetic field lines; excitation energy is lost by the emission of a photon of light, or by collision with another atom or molecule:

oxygen emissions

Green or brownish-red, depending on the amount of energy absorbed.

nitrogen emissions

Blue or red. Blue if the atom regains an electron after it has been ionized. Red if returning to ground state from an excited state.

Oxygen is unusual in terms of its return to ground state: it can take three quarters of a second to emit green light and up to two minutes to emit red. Collisions with other atoms or molecules will absorb the excitation energy and prevent emission. The very top of the atmosphere is both a higher percentage of oxygen, and so thin that such collisions are rare enough to allow time for oxygen to emit red. Collisions become more frequent progressing down into the atmosphere, so that red emissions do not have time to happen, and eventually even green light emissions are prevented.

This is why there is a colour differential with altitude; at high altitude oxygen red dominates, then oxygen green and nitrogen blue/red, then finally nitrogen blue/red when collisions prevent oxygen from emitting anything. Green is the most common of all auroras. Behind it is pink, a mixture of light green and red, followed by pure red, yellow (a mixture of red and blue), and lastly pure blue.

A predominantly red aurora australisAuroras are associated with the solar wind, a flow of ions continuously flowing outward from the sun. The Earth's magnetic field traps these particles, many of which travel toward the poles where they are accelerated toward earth. Collisions between these ions and atmospheric atoms and molecules causes energy releases in the form of auroras appearing in large circles around the poles. Auroras are more frequent and brighter during the intense phase of the solar cycle when coronal mass ejections increase the intensity of the solar wind.[2] Seen from space, these fiery curtains form a thin ring in the shape of a monk's tonsure.

chichen itza

2010-05-19T12:21:00.000-07:00

State Party Mexico

Type Cultural

Criteria i, ii, iii

Reference 483

Region** Latin America and the Caribbean

Inscription history

Inscription 1988 (12th Session

Chichen Itza (pronounced /tʃiːˈtʃɛn iːˈtsɑː/;[1] from Yucatec Maya: Chi'ch'èen Ìitsha',[2] "At the mouth of the well of the Itza") is a large pre-Columbian archaeological site built by the Maya civilization located in the northern center of the Yucatán Peninsula, in the Yucatán state, present-day Mexico.

Chichen Itza was a major focal point in the northern Maya lowlands from the Late Classic through the Terminal Classic and into the early portion of the Early Postclassic period. The site exhibits a multitude of architectural styles, from what is called “Mexicanized” and reminiscent of styles seen in central Mexico to the Puuc style found among the Puuc Maya of the northern lowlands. The presence of central Mexican styles was once thought to have been representative of direct migration or even conquest from central Mexico, but most contemporary interpretations view the presence of these non-Maya styles more as the result of cultural diffusion.
The ruins of Chichen Itza are federal property, and the site’s stewardship is maintained by Mexico’s Instituto Nacional de Antropología e Historia (National Institute of Anthropology and History, INAH). The land under the monuments had been privately-owned until March 29, 2010, when it was purchased by the state of Yucatan.

Name and orthography

Feathered Serpent, bottom of "El Castillo" staircaseThe Maya name "Chich'en Itza" means "At the mouth of the well of the Itza." This derives from chi', meaning "mouth" or "edge", and ch'e'en, meaning "well." Itzá is the name of an ethnic-lineage group that gained political and economic dominance of the northern peninsula. The name is believed to derive from the Maya itz, meaning "magic," and (h)á, meaning "water." Itzá in Spanish is often translated as "Brujas del Agua (Witches of Water)" but a more precise translation would be Magicians of Water.[citation needed]

The name is often represented as Chichén Itzá in Spanish and when translated into other languages from Spanish to show that both parts of the name are stressed on their final syllables. Other references prefer to employ a more rigorous orthography in which the word is written according to Maya language, using Chich'en Itzá (pronounced [tʃitʃʼen itsáʔ]. This form preserves the phonemic distinction between ch' and ch, since the base word ch'e'en (which, however, does have a neutral tone vowel "e" in Maya and is not accented or stressed in Maya) begins with a glottalized affricate. The word "Itzá'" has a high rise final "a" that is followed by a glottal stop (indicated by the apostrophe).

There is evidence in the Chilam Balam books that there was another, earlier name for this city prior to the arrival of the Itza hegemony in northern Yucatán. This name is difficult to define because of the absence of a single standard of orthography, but it is represented variously as Uuc Yabnal,[4] Uuc Hab Nal,[5] or Uc Abnal.[6] While most sources agree the first word means seven, there is considerable debate as to the correct translation of the rest. Among the translations suggested are “Seven Bushes,” “Seven Great Houses,” or “Seven Lines of Abnal.”

History

Cenote SagradoNorthern Yucatán is arid, and the rivers in the interior all run underground. There are two large, natural sink holes, called cenotes, that could have provided plentiful water year round at Chichen, making it attractive for settlement. Of the two cenotes, the "Cenote Sagrado" or Sacred Cenote (also variously known as the Sacred Well or Well of Sacrifice), is the most famous. According to post-Conquest sources (Maya and Spanish), pre-Columbian Maya sacrificed objects and human beings into the cenote as a form of worship to the Maya rain god Chaac. Edward Herbert Thompson dredged the Cenote Sagrado from 1904 to 1910, and recovered artifacts of gold, jade, pottery, and incense, as well as human remains.[7] A recent study of human remains taken from the Cenote Sagrado found that they had wounds consistent with human sacrifice.[8]

Kukulcan's Jaguar Throne, interior temple of "El Castillo"Ascendancy

Chichen Itza rose to regional prominence towards the end of the Early Classic period (roughly 600 AD). It was, however, towards the end of the Late Classic and into the early part of the Terminal Classic that the site became a major regional capital, centralizing and dominating political, sociocultural, economic, and ideological life in the northern Maya lowlands. The ascension of Chichen Itza roughly correlates with the decline and fragmentation of the major centers of the southern Maya lowlands, such as Tikal.

Some ethnohistoric sources claim that in about 987 a Toltec king named Topiltzin Ce Acatl Quetzalcoatl arrived here with an army from central Mexico, and (with local Maya allies) made Chichen Itza his capital, and a second Tula. The art and architecture from this period shows an interesting mix of Maya and Toltec styles. However, the recent re-dating of Chichen Itza's decline (see below) indicates that Chichen Itza is largely a Late/Terminal Classic site, while Tula remains an Early Postclassic site (thus reversing the direction of possible influence).

Golden Gate Bridge

2010-05-19T12:17:00.000-07:00

Carries	6 lanes of US 101 / SR 1 , pedestrians and bicycles
Crosses	Golden Gate
Locale	San Francisco, California and Marin County, California

History

[edit] Ferry service

Golden Gate, circa 1891

Before the bridge was built, the only practical short route between San Francisco and what is now Marin County was by boat across a section of San Francisco Bay. Ferry service began as early as 1820, with regularly scheduled service beginning in the 1840s for purposes of transporting water to San Francisco.^[5] The Sausalito Land and Ferry Company service, launched in 1867, eventually became the Golden Gate Ferry Company, a Southern Pacific Railroad subsidiary, the largest ferry operation in the world by the late 1920s.^[5]^[6] Once for railroad passengers and customers only, Southern Pacific's automobile ferries became very profitable and important to the regional economy.^[7] The ferry crossing between the Hyde Street Pier in San Francisco and Sausalito in Marin County took approximately 20 minutes and cost US$1.00 per vehicle, a price later reduced to compete with the new bridge.^[8] The trip from the San Francisco Ferry Building took 27 minutes.
Many wanted to build a bridge to connect San Francisco to Marin County. San Francisco was the largest American city still served primarily by ferry boats. Because it did not have a permanent link with communities around the bay, the city’s growth rate was below the national average.^[9] Many experts said that a bridge couldn’t be built across the 6,700 ft (2,042 m) strait. It had strong, swirling tides and currents, with water 500 ft (150 m) in depth at the center of the channel, and frequent strong winds. Experts said that ferocious winds and blinding fogs would prevent construction and operation.^[9]

Seen from edge of Baker Beach

[edit] Conception

Although the idea of a bridge spanning the Golden Gate was not new, the proposal that eventually took place was made in a 1916 San Francisco Bulletin article by former engineering student James Wilkins.^[10] San Francisco's City Engineer estimated the cost at $100 million, impractical for the time, and fielded the question to bridge engineers of whether it could be built for less.^[5] One who responded, Joseph Strauss, was an ambitious but dreamy engineer and poet who had, for his graduate thesis, designed a 55-mile (89 km) long railroad bridge across the Bering Strait.^[11] At the time, Strauss had completed some 400 drawbridges—most of which were inland—and nothing on the scale of the new project.^[3] Strauss's initial drawings^[10] were for a massive cantilever on each side of the strait, connected by a central suspension segment, which Strauss promised could be built for $17 million.^[5]
Local authorities agreed to proceed only on the assurance that Strauss alter the design and accept input from several consulting project experts.^{[citation needed]} A suspension-bridge design was considered the most practical, because of recent advances in metallurgy.^[5]
Strauss spent more than a decade drumming up support in Northern California.^[12] The bridge faced opposition, including litigation, from many sources. The Department of War was concerned that the bridge would interfere with ship traffic; the navy feared that a ship collision or sabotage to the bridge could block the entrance to one of its main harbors. Unions demanded guarantees that local workers would be favored for construction jobs. Southern Pacific Railroad, one of the most powerful business interests in California, opposed the bridge as competition to its ferry fleet and filed a lawsuit against the project, leading to a mass boycott of the ferry service.^[5] In May 1924, Colonel Herbert Deakyne held the second hearing on the Bridge on behalf of the Secretary of War in a request to use Federal land for construction. Deakyne, on behalf of the Secretary of War, approved the transfer of land needed for the bridge structure and leading roads to the "Bridging the Golden Gate Association" and both San Francisco County and Marin County, pending further bridge plans by Strauss.^[13] Another ally was the fledgling automobile industry, which supported the development of roads and bridges to increase demand for automobiles.^[8]
The bridge's name was first used when the project was initially discussed in 1917 by M.M. O'Shaughnessy, city engineer of San Francisco, and Strauss. The name became official with the passage of the Golden Gate Bridge and Highway District Act by the state legislature in 1923.^[14]

[edit] Design

South tower seen from walkway

Viewpoint of North end, showing lanes and traffic.

Strauss was chief engineer in charge of overall design and construction of the bridge project.^[9] However, because he had little understanding or experience with cable-suspension designs,^[15] responsibility for much of the engineering and architecture fell on other experts.
Irving Morrow, a relatively unknown residential architect, designed the overall shape of the bridge towers, the lighting scheme, and Art Deco elements such as the streetlights, railing, and walkways. The famous International Orange color was originally used as a sealant for the bridge. Many locals persuaded Morrow to paint the bridge in the vibrant orange color instead of the standard silver or gray, and the color has been kept ever since.^[16]
Senior engineer Charles Alton Ellis, collaborating remotely with famed bridge designer Leon Moisseiff, was the principal engineer of the project.^[17] Moisseiff produced the basic structural design, introducing his "deflection theory" by which a thin, flexible roadway would flex in the wind, greatly reducing stress by transmitting forces via suspension cables to the bridge towers.^[17] Although the Golden Gate Bridge design has proved sound, a later Moisseiff design, the original Tacoma Narrows Bridge, collapsed in a strong windstorm soon after it was completed, because of an unexpected aeroelastic flutter.^[18]
Ellis was a Greek scholar and mathematician who at one time was a University of Illinois professor of engineering despite having no engineering degree (he eventually earned a degree in civil engineering from University of Illinois prior to designing the Golden Gate Bridge and spent the last twelve years of his career as a professor at Purdue University). He became an expert in structural design, writing the standard textbook of the time.^[19] Ellis did much of the technical and theoretical work that built the bridge, but he received none of the credit in his lifetime. In November 1931, Strauss fired Ellis and replaced him with a former subordinate, Clifford Paine, ostensibly for wasting too much money sending telegrams back and forth to Moisseiff.^[19] Ellis, obsessed with the project and unable to find work elsewhere during the Depression, continued working 70 hours per week on an unpaid basis, eventually turning in ten volumes of hand calculations.^[19]
With an eye toward self-promotion and posterity, Strauss downplayed the contributions of his collaborators who, despite receiving little recognition or compensation,^[15] are largely responsible for the final form of the bridge. He succeeded in having himself credited as the person most responsible for the design and vision of the bridge.^[19] Only much later were the contributions of the others on the design team properly appreciated.^[19] In May 2007, the Golden Gate Bridge District issued a formal report on 70 years of stewardship of the famous bridge and decided to give Ellis major credit for the design of the bridge.

[edit] Finance

The Golden Gate Bridge and Highway District, authorized by an act of the California Legislature, was incorporated in 1928 as the official entity to design, construct, and finance the Golden Gate Bridge.^[9] However, after the Wall Street Crash of 1929, the District was unable to raise the construction funds, so it lobbied for a $38 million bond measure. The bonds were approved in November 1930,^[11] by votes in the counties affected by the bridge.^[20] The construction budget at the time of approval was $30.1 million. However, the District was unable to sell the bonds until 1932, when Amadeo Giannini, the founder of San Francisco–based Bank of America, agreed on behalf of his bank to buy the entire issue in order to help the local economy.^[5]

On the south side of the bridge, a 36.5 inches (93 cm) wide cross-section of the cable, containing 27,572 separate wires, is on display.

[edit] Construction

Construction began on January 5, 1933.^[5] The project cost more than $35 million.^[21]
Strauss remained head of the project, overseeing day-to-day construction and making some groundbreaking contributions. A graduate of the University of Cincinnati, he had placed a brick from his alma mater's demolished McMicken Hall in the south anchorage before the concrete was poured. He innovated the use of movable safety netting beneath the construction site, which saved the lives of many otherwise-unprotected steelworkers. Of eleven men killed from falls during construction, ten were killed (when the bridge was near completion) when the net failed under the stress of a scaffold that had fallen. Nineteen others who were saved by the net over the course of construction became proud members of the (informal) Halfway to Hell Club.^[22]
The project was finished by April 1937, $1.3 million under budget.^[5]

[edit] Opening festivities

Opening of the Golden Gate Bridge

The bridge-opening celebration began on May 27, 1937 and lasted for one week. The day before vehicle traffic was allowed, 200,000 people crossed by foot and roller skate.^[5] On opening day, Mayor Angelo Rossi and other officials rode the ferry to Marin, then crossed the bridge in a motorcade past three ceremonial "barriers," the last a blockade of beauty queens who required Joseph Strauss to present the bridge to the Highway District before allowing him to pass. An official song, "There's a Silver Moon on the Golden Gate," was chosen to commemorate the event. Strauss wrote a poem that is now on the Golden Gate Bridge entitled "The Mighty Task is Done." The next day, President Roosevelt pushed a button in Washington, DC signaling the official start of vehicle traffic over the Bridge at noon. When the celebration got out of hand, the SFPD had a small riot in the uptown Polk Gulch area. Weeks of civil and cultural activities called "the Fiesta" followed. A statue of Strauss was moved in 1955 to a site near the bridge.^[10]

[edit] Description

[edit] Specifications

A photograph of the bridge from a boat underneath

Fog at the Golden Gate Bridge, San Francisco

The center span was the longest among suspension bridges until 1964 when the Verrazano-Narrows Bridge was erected between the boroughs of Staten Island and Brooklyn in New York City, surpassing the Golden Gate Bridge by 60 feet (18 m).The Golden Gate Bridge also had the world's tallest suspension towers at the time of construction and retained that record until more recently. In 1957, Michigan's Mackinac Bridge surpassed the Golden Gate Bridge's total length to become the world's longest two-tower suspension bridge in total length between anchorages, but the Mackinac Bridge has a shorter suspended span (between towers) compared to the Golden Gate Bridge.

[edit] Structure

The weight of the roadway is hung from two cables that pass through the two main towers and are fixed in concrete at each end. Each cable is made of 27,572 strands of wire. There are 80,000 miles (129,000 km) of wire in the main cables.^[23] The bridge has approximately 1,200,000 total rivets.

[edit] Traffic

Traffic crossing the Bridge during a foggy morning

As the only road to exit San Francisco to the north, the bridge is part of both U.S. Route 101 and California Route 1. The median markers between the lanes are moved to conform to traffic patterns. On weekday mornings, traffic flows mostly southbound into the city, so four of the six lanes run southbound. Conversely, on weekday afternoons, four lanes run northbound. Although there has been discussion concerning the installation of a movable barrier since the 1980s, the Bridge Board of Directors, in March 2005, committed to finding funding to complete the $2 million study required prior to the installation of a movable median barrier. The eastern walkway is for pedestrians and bicycles during the weekdays and during daylight hours only, and the western walkway is open to bicyclists on weekday afternoons, weekends, and holidays. The speed limit on the Golden Gate Bridge was reduced from 55 mph (89 km/h) to 45 mph (72 km/h) on 1 October 1996.

[edit] Aesthetics

The Golden Gate Bridge by night, with part of downtown San Francisco visible in the background at far left

Despite its red appearance, the color of the bridge is officially an orange vermillion called international orange.^[24] The color was selected by consulting architect Irving Morrow because it compliments the natural surroundings and enhances the bridge's visibility in fog.
The bridge is said to be one of the most beautiful examples of bridge engineering, both as a structural design challenge and for its aesthetic appeal. It was declared one of the modern Wonders of the World by the American Society of Civil Engineers. According to Frommer's travel guide, the Golden Gate Bridge is "possibly the most beautiful, certainly the most photographed, bridge in the world"^[25] (although Frommers also bestows the most photographed honor on Tower Bridge in London, England).^[26]
Aesthetics was the foremost reason why the first design of Joseph Strauss was rejected. Upon re-submission of his bridge construction plan, he added details, such as lighting, to outline the bridge's cables and towers.^[27]

[edit] Paintwork

The bridge was originally painted with red lead primer and a lead-based topcoat, which was touched up as required. In the mid-1960s, a program was started to improve corrosion protection by stripping the original paint and repainting the bridge with zinc silicate primer and vinyl topcoats.^[28]^[29] Since 1990 Acrylic topcoats have been used instead for air-quality reasons. The program was completed in 1995 and it is now maintained by 38 painters who touch up the paintwork where it becomes seriously eroded.^[30]

Golden Gate Bridge, with its approach arch over Fort Point at the San Francisco terminus (right). Behind the arch is Angel Island, and to the left of that, Tiburon, California, mostly obscuring the East Bay hills.

[edit] Current issues

[edit] Economics

The last of the construction bonds were retired in 1971, with $35 million in principal and nearly $39 million in interest raised entirely from bridge tolls.^[31]
In November 2006, the Golden Gate Bridge, Highway and Transportation District recommended a corporate sponsorship program for the bridge to address its operating deficit, projected at $80 million over five years. The District promised that the proposal, which it called a "partnership program," would not include changing the name of the bridge or placing advertising on the bridge itself. In October 2007, the Board unanimously voted to discontinue the proposal and seek additional revenue through other means, most likely a toll increase.^[32]^[33]
On 2 September 2008, the auto cash toll for all southbound motor vehicles was raised from $5 to $6, and the FasTrak toll was increased from $4 to $5. Bicycle, pedestrian, and northbound motor vehicle traffic remain toll free.^[34] For vehicles with more than two axles, the toll rate is $2.50 per axle.^[35]^[36]

[edit] Congestion pricing

Further information: San Francisco congestion pricing

In March 2008, the Golden Gate Bridge District board approved a resolution to implement congestion pricing at the Golden Gate Bridge, charging higher tolls during peak hours, but rising and falling depending on traffic levels. This decision allowed the Bay Area to meet the federal requirement to receive $158 million in federal transportation funds from USDOT Urban Partnership grant.^[37] As a condition of the grant, the congestion toll must be in place by September 2009.^[38]^[39]
The first results of the study, called the Mobility, Access and Pricing Study (MAPS), showed that a congestion pricing program is feasible.^[40] The different pricing scenarios considered were presented in public meetings in December 2008 and the final study results are expected for late 2009.^[41]

San Francisco with two bridges, Coit Tower and Fort Mason from the Marin Headlands

[edit] Suicides

As a suicide prevention initiative, this sign promotes a special telephone available on the bridge that connects to a crisis hotline.

The Golden Gate Bridge is not only the most popular place to commit suicide in the United States^[42] but the most popular in the entire world.^[43] The deck is approximately 245 feet (75 m) above the water.^[44] After a fall of approximately four seconds, jumpers hit the water at some 76 miles per hour (122 km/h). At such a speed, water has proven to take on properties similar to concrete. Because of this, most jumpers die on their immediate contact with the water. The few who survive the initial impact generally drown or die of hypothermia in the cold water.
An official suicide count was kept, sorted according to which of the bridge's 128 lamp posts the jumper was nearest when he or she jumped. By 2005, this count exceeded 1,200 and new suicides were averaging one every two weeks.^[45] For comparison, the reported second-most-popular place to commit suicide in the world, Aokigahara Forest in Japan, has a record of 78 bodies, found within the forest in 2002, with an average of 30 a year.^[46] There were 34 bridge-jump suicides in 2006 whose bodies were recovered, in addition to four jumps that were witnessed but whose bodies were never recovered, and several bodies recovered suspected to be from bridge jumps. The California Highway Patrol removed 70 apparently suicidal people from the bridge that year.^[47]
There is no accurate figure on the number of suicides or successful jumps since 1937, because many were not witnessed. People have been known to travel to San Francisco specifically to jump off the bridge, and may take a bus or cab to the site; police sometimes find abandoned rental cars in the parking lot. Currents beneath the bridge are very strong, and some jumpers have undoubtedly been washed out to sea without ever being seen. The water may be as cold as 47 °F (8 °C).
The fatality rate of jumping is roughly 98%. As of 2006, only 26 people are known to have survived the jump.^[45] Those who do survive strike the water feet-first and at a slight angle, although individuals may still sustain broken bones or internal injuries. One young man survived a jump in 1979, swam to shore, and drove himself to a hospital. The impact cracked several of his vertebrae.^[48]
Engineering professor Natalie Jeremijenko, as part of her Bureau of Inverse Technology art collective, created a "Despondency Index" by correlating the Dow Jones Industrial Average with the number of jumpers detected by "Suicide Boxes" containing motion-detecting cameras, which she claimed to have set up under the bridge.^[49] The boxes purportedly recorded 17 jumps in three months, far greater than the official count. The Whitney Museum, although questioning whether Jeremijenko's suicide-detection technology actually existed, nevertheless included her project in its prestigious Whitney Biennial.^[50]
Various methods have been proposed and implemented to reduce the number of suicides. The bridge is fitted with suicide hotline telephones, and staff patrol the bridge in carts, looking for people who appear to be planning to jump. Iron workers on the bridge also volunteer their time to prevent suicides by talking or wrestling down suicidal people.^[51] The bridge is now closed to pedestrians at night. Cyclists are still permitted across at night, but must be buzzed in and out through the remotely controlled security gates.^[52] Attempts to introduce a suicide barrier had been thwarted by engineering difficulties, high costs, and public opposition.^[53] One recurring proposal had been to build a barrier to replace or augment the low railing, a component of the bridge's original architectural design. New barriers have eliminated suicides at other landmarks around the world, but were opposed for the Golden Gate Bridge for reasons of cost, aesthetics, and safety (the load from a poorly designed barrier could significantly affect the bridge's structural integrity during a strong windstorm).
Strong appeals for a suicide barrier, fence, or other preventive measures were raised once again by a well-organized vocal minority of psychiatry professionals, suicide barrier consultants, and families of jumpers after the release of the controversial 2006 documentary film The Bridge, in which filmmaker Eric Steel and his production crew spent one year (2004) filming the bridge from several vantage points, in order to film actual suicide jumps. The film caught 23 jumps, most notably that of Gene Sprague as well as a handful of thwarted attempts. The film also contained interviews with surviving family members of those who jumped; interviews with witnesses; and, in one segment, an interview with Kevin Hines who, as a 19-year-old in 2000, survived a suicide plunge from the span and is now a vocal advocate for some type of bridge barrier or net to prevent such incidents from occurring.
On October 10, 2008, the Golden Gate Bridge Board of Directors voted 14 to 1 to install a plastic-covered stainless-steel net below the bridge as a suicide deterrent. The net will extend 20 feet (6 m) on either side of the bridge and is expected to cost $40–50 million to complete.^[54]^[55] However, lack of funding could delay the net's construction.^[56] See also Suicide bridge.

[edit] Wind

Air show over Golden Gate Bridge

Since its completion, the Golden Gate Bridge has been closed due to weather conditions only three times: on 1 December 1951, because of gusts of 69 mph (111 km/h); on 23 December 1982, because of winds of 70 mph (113 km/h); and on 3 December 1983, because of wind gusts of 75 mph (121 km/h).^[57]

[edit] Seismic retrofit

Vertical section of Golden Gate Bridge span

Modern knowledge of the effect of earthquakes on structures led to a program to retrofit the Golden Gate to better resist seismic events. The proximity of the bridge to the San Andreas Fault places it at risk for a significant earthquake. Once thought to have been able to withstand any magnitude of foreseeable earthquake, the bridge was actually vulnerable to complete structural failure (i.e., collapse) triggered by the failure of supports on the 320-foot (98 m) arch over Fort Point.^[58] A $392 million program was initiated to improve the structure's ability to withstand such an event with only minimal (repairable) damage. The retrofit's planned completion date is 2012.^[59]^[60]

[edit] Doyle Drive replacement project

The elevated approach to the Golden Gate Bridge through the San Francisco Presidio is popularly known as Doyle Drive. Doyle Drive, dating back to 1933 was named after Frank P. Doyle, director of the California State Automobile Association.^[61] The highway carries approximately 91,000 vehicles each weekday between downtown San Francisco and suburban Marin County.^[62] However, the road has been deemed "vulnerable to earthquake damage", has a problematic 4-lane design, and lacks shoulders. For these reasons, a San Francisco County Transportation Authority study recommended that the current outdated structure be replaced with a more modern, efficient, and multimodal transportation structure. Construction on the $1 billion^[63] replacement, known as the Presidio Parkway, began in December 2009^[64] and is expected to be completed in 2013.

Colosseum

2010-05-18T13:38:00.000-07:00

The Colosseum or Roman Coliseum, originally the Flavian Amphitheatre

Name

The Colosseum's original Latin name was Amphitheatrum Flavium, often anglicized as Flavian Amphitheater. The building was constructed by emperors of the Flavian dynasty, hence its original name, after the reign of Emperor Nero.^[7] This name is still used in modern English, but generally the structure is better known as the Colosseum. In antiquity, Romans may have referred to the Colosseum by the unofficial name Amphitheatrum Caesareum; this name could have been strictly poetic.^[8]^[9] This name was not exclusive to the Colosseum; Vespasian and Titus, builders of the Colosseum, also constructed an amphitheater of the same name in Puteoli (modern Pozzuoli).^[10]
The name Colosseum has long been believed to be derived from a colossal statue of Nero nearby.^[3] This statue was later remodeled by Nero's successors into the likeness of Helios (Sol) or Apollo, the sun god, by adding the appropriate solar crown. Nero's head was also replaced several times with the heads of succeeding emperors. Despite its pagan links, the statue remained standing well into the medieval era and was credited with magical powers. It came to be seen as an iconic symbol of the permanence of Rome.
In the 8th century, the Venerable Bede (c. 672–735) wrote a famous epigram celebrating the symbolic significance of the statue, Quandiu stabit coliseus, stabit et Roma; quando cadit coliseus, cadet et Roma; quando cadet Roma, cadet et mundus ("as long as the Colossus stands, so shall Rome; when the Colossus falls, Rome shall fall; when Rome falls, so falls the world").^[11] This is often mistranslated to refer to the Colosseum rather than the Colossus (as in, for instance, Byron's poem Childe Harold's Pilgrimage). However, at the time that Bede wrote, the masculine noun coliseus was applied to the statue rather than to what was still known as the Flavian amphitheatre.
The Colossus did eventually fall, possibly being pulled down to reuse its bronze. By the year 1000 the name "Colosseum" had been coined to refer to the amphitheatre. The statue itself was largely forgotten and only its base survives, situated between the Colosseum and the nearby Temple of Venus and Roma.^[12]
The name was further corrupted to Coliseum during the Middle Ages. In Italy, the amphitheatre is still known as il Colosseo, and other Romance languages have come to use similar forms such as le Colisée (French), el Coliseo (Spanish) and o Coliseu (Portuguese).

History

Ancient

A map of central Rome during the Roman Empire, with the Colosseum at the upper right corner

Construction of the Colosseum began under the rule of the Emperor Vespasian^[3] in around 70–72AD. The site chosen was a flat area on the floor of a low valley between the Caelian, Esquiline and Palatine Hills, through which a canalised stream ran. By the 2nd century BC the area was densely inhabited. It was devastated by the Great Fire of Rome in AD 64, following which Nero seized much of the area to add to his personal domain. He built the grandiose Domus Aurea on the site, in front of which he created an artificial lake surrounded by pavilions, gardens and porticoes. The existing Aqua Claudia aqueduct was extended to supply water to the area and the gigantic bronze Colossus of Nero was set up nearby at the entrance to the Domus Aurea.^[12]
Although the Colossus was preserved, much of the Domus Aurea was torn down. The lake was filled in and the land reused as the location for the new Flavian Amphitheatre. Gladiatorial schools and other support buildings were constructed nearby within the former grounds of the Domus Aurea. According to a reconstructed inscription found on the site, "the emperor Vespasian ordered this new amphitheatre to be erected from his general's share of the booty." This is thought to refer to the vast quantity of treasure seized by the Romans following their victory in the Great Jewish Revolt in 70AD. The Colosseum can be thus interpreted as a great triumphal monument built in the Roman tradition of celebrating great victories.^[12] Vespasian's decision to build the Colosseum on the site of Nero's lake can also be seen as a populist gesture of returning to the people an area of the city which Nero had appropriated for his own use. In contrast to many other amphitheatres, which were located on the outskirts of a city, the Colosseum was constructed in the city centre; in effect, placing it both literally and symbolically at the heart of Rome.
The Colosseum had been completed up to the third story by the time of Vespasian's death in 79. The top level was finished and the building inaugurated by his son, Titus, in 80.^[3] Dio Cassius recounts that over 9,000 wild animals were killed during the inaugural games of the amphitheatre. The building was remodelled further under Vespasian's younger son, the newly designated Emperor Domitian, who constructed the hypogeum, a series of underground tunnels used to house animals and slaves. He also added a gallery to the top of the Colosseum to increase its seating capacity.
In 217, the Colosseum was badly damaged by a major fire (caused by lightning, according to Dio Cassius^[13]) which destroyed the wooden upper levels of the amphitheatre's interior. It was not fully repaired until about 240 and underwent further repairs in 250 or 252 and again in 320. An inscription records the restoration of various parts of the Colosseum under Theodosius II and Valentinian III (reigned 425–455), possibly to repair damage caused by a major earthquake in 443; more work followed in 484^[14] and 508. The arena continued to be used for contests well into the 6th century, with gladiatorial fights last mentioned around 435. Animal hunts continued until at least 523, when Anicius Maximus celebrated his consulship with some venationes, criticised by King Theodoric the Great for their high cost.^[12]

Medieval

Map of medieval Rome depicting the Colosseum

The Colosseum underwent several radical changes of use during the medieval period. By the late 6th century a small church had been built into the structure of the amphitheatre, though this apparently did not confer any particular religious significance on the building as a whole. The arena was converted into a cemetery. The numerous vaulted spaces in the arcades under the seating were converted into housing and workshops, and are recorded as still being rented out as late as the 12th century. Around 1200 the Frangipani family took over the Colosseum and fortified it, apparently using it as a castle.
Severe damage was inflicted on the Colosseum by the great earthquake in 1349, causing the outer south side, lying on a less stable alluvional terrain, to collapse. Much of the tumbled stone was reused to build palaces, churches, hospitals and other buildings elsewhere in Rome. A religious order moved into the northern third of the Colosseum in the mid-14th century and continued to inhabit it until as late as the early 19th century. The interior of the amphitheatre was extensively stripped of stone, which was reused elsewhere, or (in the case of the marble façade) was burned to make quicklime.^[12] The bronze clamps which held the stonework together were pried or hacked out of the walls, leaving numerous pockmarks which still scar the building today.

Modern

Interior of the Colosseum, Rome. Thomas Cole, 1832. Note the Stations of the Cross around the arena and the extensive vegetation, both removed later in the 19th century.

During the 16th and 17th century, Church officials sought a productive role for the vast derelict hulk of the Colosseum. Pope Sixtus V (1585–1590) planned to turn the building into a wool factory to provide employment for Rome's prostitutes, though this proposal fell through with his premature death.^[15] In 1671 Cardinal Altieri authorized its use for bullfights; a public outcry caused the idea to be hastily abandoned.

The Colosseum in a 1757 engraving by Giovanni Battista Piranesi

In 1749, Pope Benedict XIV endorsed as official Church policy the view that the Colosseum was a sacred site where early Christians had been martyred. He forbade the use of the Colosseum as a quarry and consecrated the building to the Passion of Christ and installed Stations of the Cross, declaring it sanctified by the blood of the Christian martyrs who perished there (see Christians and the Colosseum). However there is no historical evidence to support Benedict's claim, nor is there even any evidence that anyone prior to the 16th century suggested this might be the case; the Catholic Encyclopedia concludes that there are no historical grounds for the supposition. Later popes initiated various stabilization and restoration projects, removing the extensive vegetation which had overgrown the structure and threatened to damage it further. The façade was reinforced with triangular brick wedges in 1807 and 1827, and the interior was repaired in 1831, 1846 and in the 1930s. The arena substructure was partly excavated in 1810–1814 and 1874 and was fully exposed under Benito Mussolini in the 1930s.^[12]

Between 1993 and 2000, parts of the outer wall were cleaned (left) to repair the Colosseum from automobile exhaust damage (right)

The Colosseum is today one of Rome's most popular tourist attractions, receiving millions of visitors annually. The effects of pollution and general deterioration over time prompted a major restoration programme carried out between 1993 and 2000, at a cost of 40 billion Italian lire ($19.3m / €20.6m at 2000 prices). In recent years it has become a symbol of the international campaign against capital punishment, which was abolished in Italy in 1948. Several anti–death penalty demonstrations took place in front of the Colosseum in 2000. Since that time, as a gesture against the death penalty, the local authorities of Rome change the color of the Colosseum's night time illumination from white to gold whenever a person condemned to the death penalty anywhere in the world gets their sentence commuted or is released,^[16] or if a jurisdiction abolishes the death penalty. Most recently, the Colosseum was illuminated in gold when capital punishment was abolished in the American state of New Mexico in April 2009.^[17]

Today, the Colosseum is a background to the busy metropolis that is modern Rome.

Because of the ruined state of the interior, it is impractical to use the Colosseum to host large events; only a few hundred spectators can be accommodated in temporary seating. However, much larger concerts have been held just outside, using the Colosseum as a backdrop. Performers who have played at the Colosseum in recent years have included Ray Charles (May 2002),^[18] Paul McCartney (May 2003),^[19] and Elton John (September 2005).^[20]

Physical description

Exterior

The exterior of the Colosseum, showing the partially intact outer wall (left) and the mostly intact inner wall (right)

Original façade of the Colosseum

Entrance LII of the Colosseum, with Roman numerals still visible

Cross-section from the Lexikon der gesamten Technik (1904)

Unlike earlier Greek theatres that were built into hillsides, the Colosseum is an entirely free-standing structure. It derives its basic exterior and interior architecture from that of two Roman theatres back to back. It is elliptical in plan and is 189 meters (615 ft / 640 Roman feet) long, and 156 meters (510 ft / 528 Roman feet) wide, with a base area of 6 acres (24,000 m²). The height of the outer wall is 48 meters (157 ft / 165 Roman feet). The perimeter originally measured 545 meters (1,788 ft / 1,835 Roman feet). The central arena is an oval 87 m (287 ft) long and 55 m (180 ft) wide, surrounded by a wall 5 m (15 ft) high, above which rose tiers of seating.
The outer wall is estimated to have required over 100,000 cubic meters (131,000 cu yd) of travertine stone which were set without mortar held together by 300 tons of iron clamps.^[12] However, it has suffered extensive damage over the centuries, with large segments having collapsed following earthquakes. The north side of the perimeter wall is still standing; the distinctive triangular brick wedges at each end are modern additions, having been constructed in the early 19th century to shore up the wall. The remainder of the present-day exterior of the Colosseum is in fact the original interior wall.
The surviving part of the outer wall's monumental façade comprises three stories of superimposed arcades surmounted by a podium on which stands a tall attic, both of which are pierced by windows interspersed at regular intervals. The arcades are framed by half-columns of the Doric, Ionic, and Corinthian orders, while the attic is decorated with Corinthian pilasters.^[21] Each of the arches in the second- and third-floor arcades framed statues, probably honoring divinities and other figures from Classical mythology.
Two hundred and forty mast corbels were positioned around the top of the attic. They originally supported a retractable awning, known as the velarium, that kept the sun and rain off spectators. This consisted of a canvas-covered, net-like structure made of ropes, with a hole in the center.^[3] It covered two-thirds of the arena, and sloped down towards the center to catch the wind and provide a breeze for the audience. Sailors, specially enlisted from the Roman naval headquarters at Misenum and housed in the nearby Castra Misenatium, were used to work the velarium.^[22]
The Colosseum's huge crowd capacity made it essential that the venue could be filled or evacuated quickly. Its architects adopted solutions very similar to those used in modern stadiums to deal with the same problem. The amphitheatre was ringed by eighty entrances at ground level, 76 of which were used by ordinary spectators.^[3] Each entrance and exit was numbered, as was each staircase. The northern main entrance was reserved for the Roman Emperor and his aides, whilst the other three axial entrances were most likely used by the elite. All four axial entrances were richly decorated with painted stucco reliefs, of which fragments survive. Many of the original outer entrances have disappeared with the collapse of the perimeter wall, but entrances XXIII (23) to LIV (54) still survive.^[12]
Spectators were given tickets in the form of numbered pottery shards, which directed them to the appropriate section and row. They accessed their seats via vomitoria (singular vomitorium), passageways that opened into a tier of seats from below or behind. These quickly dispersed people into their seats and, upon conclusion of the event or in an emergency evacuation, could permit their exit within only a few minutes. The name vomitoria derived from the Latin word for a rapid discharge, from which English derives the word vomit.

Interior seating

Side view of Colosseum seating

According to the Codex-Calendar of 354, the Colosseum could accommodate 87,000 people, although modern estimates put the figure at around 50,000. They were seated in a tiered arrangement that reflected the rigidly stratified nature of Roman society. Special boxes were provided at the north and south ends respectively for the Emperor and the Vestal Virgins, providing the best views of the arena. Flanking them at the same level was a broad platform or podium for the senatorial class, who were allowed to bring their own chairs. The names of some 5th century senators can still be seen carved into the stonework, presumably reserving areas for their use.
The tier above the senators, known as the maenianum primum, was occupied by the non-senatorial noble class or knights (equites). The next level up, the maenianum secundum, was originally reserved for ordinary Roman citizens (plebians) and was divided into two sections. The lower part (the immum) was for wealthy citizens, while the upper part (the summum) was for poor citizens. Specific sectors were provided for other social groups: for instance, boys with their tutors, soldiers on leave, foreign dignitaries, scribes, heralds, priests and so on. Stone (and later marble) seating was provided for the citizens and nobles, who presumably would have brought their own cushions with them. Inscriptions identified the areas reserved for specific groups.
Another level, the maenianum secundum in legneis, was added at the very top of the building during the reign of Domitian. This comprised a gallery for the common poor, slaves and women. It would have been either standing room only, or would have had very steep wooden benches. Some groups were banned altogether from the Colosseum, notably gravediggers, actors and former gladiators.^[12]
Each tier was divided into sections (maeniana) by curved passages and low walls (praecinctiones or baltei), and were subdivided into cunei, or wedges, by the steps and aisles from the vomitoria. Each row (gradus) of seats was numbered, permitting each individual seat to be exactly designated by its gradus, cuneus, and number.^[23]

Arena and hypogeum

The Colosseum arena, showing the hypogeum. The wooden walkway is a modern structure.

Detail of the hypogeum

The arena itself was 83 meters by 48 meters (272 ft by 157 ft / 280 by 163 Roman feet).^[12] It comprised a wooden floor covered by sand (the Latin word for sand is harena or arena), covering an elaborate underground structure called the hypogeum (literally meaning "underground"). Little now remains of the original arena floor, but the hypogeum is still clearly visible. It consisted of a two-level subterranean network of tunnels and cages beneath the arena where gladiators and animals were held before contests began. Eighty vertical shafts provided instant access to the arena for caged animals and scenery pieces concealed underneath; larger hinged platforms, called hegmata, provided access for elephants and the like. It was restructured on numerous occasions; at least twelve different phases of construction can be seen.^[12]
The hypogeum was connected by underground tunnels to a number of points outside the Colosseum. Animals and performers were brought through the tunnel from nearby stables, with the gladiators' barracks at the Ludus Magnus to the east also being connected by tunnels. Separate tunnels were provided for the Emperor and the Vestal Virgins to permit them to enter and exit the Colosseum without needing to pass through the crowds.^[12]
Substantial quantities of machinery also existed in the hypogeum. Elevators and pulleys raised and lowered scenery and props, as well as lifting caged animals to the surface for release. There is evidence for the existence of major hydraulic mechanisms^[12] and according to ancient accounts, it was possible to flood the arena rapidly, presumably via a connection to a nearby aqueduct.

Supporting buildings

The Colosseum - a view from the Oppian Hill

The Colosseum and its activities supported a substantial industry in the area. In addition to the amphitheatre itself, many other buildings nearby were linked to the games. Immediately to the east is the remains of the Ludus Magnus, a training school for gladiators. This was connected to the Colosseum by an underground passage, to allow easy access for the gladiators. The Ludus Magnus had its own miniature training arena, which was itself a popular attraction for Roman spectators. Other training schools were in the same area, including the Ludus Matutinus (Morning School), where fighters of animals were trained, plus the Dacian and Gallic Schools.
Also nearby were the Armamentarium, comprising an armory to store weapons; the Summum Choragium, where machinery was stored; the Sanitarium, which had facilities to treat wounded gladiators; and the Spoliarium, where bodies of dead gladiators were stripped of their armor and disposed of.
Around the perimeter of the Colosseum, at a distance of 18 m (59 ft) from the perimeter, was a series of tall stone posts, with five remaining on the eastern side. Various explanations have been advanced for their presence; they may have been a religious boundary, or an outer boundary for ticket checks, or an anchor for the velarium or awning.^[12]
Right next to the Colosseum is also the Arch of Constantine.

Use

Pollice Verso ("Thumbs Down") by Jean-Léon Gérôme, 1872

The Colosseum was used to host gladiatorial shows as well as a variety of other events. The shows, called munera, were always given by private individuals rather than the state. They had a strong religious element but were also demonstrations of power and family prestige, and were immensely popular with the population. Another popular type of show was the animal hunt, or venatio. This utilized a great variety of wild beasts, mainly imported from Africa and the Middle East, and included creatures such as rhinoceros, hippopotamuses, elephants, giraffes, aurochs, wisents, barbary lions, panthers, leopards, bears, caspian tigers, crocodiles and ostriches. Battles and hunts were often staged amid elaborate sets with movable trees and buildings. Such events were occasionally on a huge scale; Trajan is said to have celebrated his victories in Dacia in 107 with contests involving 11,000 animals and 10,000 gladiators over the course of 123 days.
During the early days of the Colosseum, ancient writers recorded that the building was used for naumachiae (more properly known as navalia proelia) or simulated sea battles. Accounts of the inaugural games held by Titus in AD 80 describe it being filled with water for a display of specially trained swimming horses and bulls. There is also an account of a re-enactment of a famous sea battle between the Corcyrean (Corfiot) Greeks and the Corinthians. This has been the subject of some debate among historians; although providing the water would not have been a problem, it is unclear how the arena could have been waterproofed, nor would there have been enough space in the arena for the warships to move around. It has been suggested that the reports either have the location wrong, or that the Colosseum originally featured a wide floodable channel down its central axis (which would later have been replaced by the hypogeum).^[12]
Sylvae or recreations of natural scenes were also held in the arena. Painters, technicians and architects would construct a simulation of a forest with real trees and bushes planted in the arena's floor. Animals would be introduced to populate the scene for the delight of the crowd. Such scenes might be used simply to display a natural environment for the urban population, or could otherwise be used as the backdrop for hunts or dramas depicting episodes from mythology. They were also occasionally used for executions in which the hero of the story — played by a condemned person — was killed in one of various gruesome but mythologically authentic ways, such as being mauled by beasts or burned to death.

Today

The Colosseum today is now a major tourist attraction in Rome with thousands of tourists each year paying to view the interior arena, though entrance for EU citizens is partially subsidised, and under-18 and over-65 EU citizens' entrances are free.^[24] There is now a museum dedicated to Eros located in the upper floor of the outer wall of the building. Part of the arena floor has been re-floored.
The Colosseum is also the site of Roman Catholic ceremonies in the 20th and 21st centuries. For instance, Pope Benedict XVI leads the Stations of the Cross called the Scriptural Way of the Cross (which calls for more meditation) at the Colosseum^[25]^[26] on Good Fridays.^[6]

A panorama of the interior of the Colosseum as it stands now.

Christians and the Colosseum

The Christian Martyrs' Last Prayer, by Jean-Léon Gérôme (1883).

In the Middle Ages, the Colosseum was clearly not regarded as a sacred site. Its use as a fortress and then a quarry demonstrates how little spiritual importance was attached to it, at a time when sites associated with martyrs were highly venerated. It was not included in the itineraries compiled for the use of pilgrims nor in works such as the 12th century Mirabilia Urbis Romae ("Marvels of the City of Rome"), which claims the Circus Flaminius — but not the Colosseum — as the site of martyrdoms. Part of the structure was inhabited by a Christian order, but apparently not for any particular religious reason.
It appears to have been only in the 16th and 17th centuries that the Colosseum came to be regarded as a Christian site. Pope Pius V (1566–1572) is said to have recommended that pilgrims gather sand from the arena of the Colosseum to serve as a relic, on the grounds that it was impregnated with the blood of martyrs. This seems to have been a minority view until it was popularised nearly a century later by Fioravante Martinelli, who listed the Colosseum at the head of a list of places sacred to the martyrs in his 1653 book Roma ex ethnica sacra.
Martinelli's book evidently had an effect on public opinion; in response to Cardinal Altieri's proposal some years later to turn the Colosseum into a bullring, Carlo Tomassi published a pamphlet in protest against what he regarded as an act of desecration. The ensuing controversy persuaded Pope Clement X to close the Colosseum's external arcades and declare it a sanctuary, though quarrying continued for some time.
At the instance of St. Leonard of Port Maurice, Pope Benedict XIV (1740–1758) forbade the quarrying of the Colosseum and erected Stations of the Cross around the arena, which remained until February 1874. St. Benedict Joseph Labre spent the later years of his life within the walls of the Colosseum, living on alms, prior to his death in 1783. Several 19th century popes funded repair and restoration work on the Colosseum, and it still retains a Christian connection today. Crosses stand in several points around the arena and every Good Friday the Pope leads a Via Crucis procession to the amphitheatre.

Flora

Plants on the inner walls of the Colosseum

The Colosseum has a wide and well-documented history of flora ever since Domenico Panaroli made the first catalogue of its plants in 1643. Since then, 684 species have been identified there. The peak was in 1855 (420 species). Attempts were made in 1871 to eradicate the vegetation, because of concerns over the damage that was being caused to the masonry, but much of it has returned.^[12] 242 species have been counted today and of the species first identified by Panaroli, 200 remain.
The variation of plants can be explained by the change of climate in Rome through the centuries. Additionally, bird migration, flower blooming, and the growth of Rome that caused the Colosseum to become embedded within the modern city centre rather than on the outskirts of the ancient city, as well as deliberate transport of species, are also contributing causes. One other romantic reason often given is their seeds being unwittingly transported on the animals brought there from all corners of the empire.

Appearances in media

The iconic status of the Colosseum has led it to be featured in numerous films and other items of popular culture:

Cole Porter's song "You're the Top" from the musical Anything Goes (1934) includes the line "You're the Top, You're the Colosseum".
In the 1953 film Roman Holiday, the Colosseum famously serves as the backdrop for several scenes.
In the 1954 film Demetrius and the Gladiators, the Emperor Caligula anachronistically sentences the Christian Demetrius to fight in the Colosseum.
The conclusion of the 1957 film 20 Million Miles to Earth takes place at the Colosseum.
In the 1972 film Way of the Dragon, Bruce Lee fought Chuck Norris in the Colosseum.
In 1998 the Colosseum becomes a featured Santa Cam location for the annual NORAD Tracks Santa tracking effort.^[27]
In Ridley Scott's 2000 film Gladiator, the Colosseum was re-created via computer-generated imagery (CGI) to "restore" it to the glory of its heyday in the 2nd century. The depiction of the building itself is generally accurate and it gives a good impression of what the underground hypogeum would have been like.^{[citation needed]}
In the 2003 science fiction film The Core, the Colosseum along with the rest of Rome is destroyed by a huge lightning superstorm.
In 2003, the Colosseum appeared in the video game Mario Kart: Double Dash!!, with the race track Wario Colosseum located in the building.
In 2004, the remaining girls of America's Next Top Model, Cycle 2 did a photoshoot in the Colosseum for Solstice Sunglasses.
In the 2008 film Jumper, the Colosseum was used as the location for one of the battles between the jumpers and the paladins.

The Colosseum's fame as an entertainment venue has also led the name to be re-used for modern entertainment facilities, particularly in the United States, where theatres, music halls and large buildings used for sport or exhibitions have commonly been called Colosseums or Coliseums.^[28]

The optical disc authoring software program Nero Burning ROM uses an image of the Colosseum on fire as one of its main icons, even though Emperor Nero's Great Fire of Rome (which the program's name and icon refer to) occurred in 64 AD, before the Colosseum was built.
In 2009 Nickelback used the Colosseum to film their latest Music Video, entitled "Gotta be somebody".
In 2010, an episode of Life After People: The Series titled "Wrath of God" features the structure's long demise after the disappearance of humans.

Hagia Sophia

2010-05-18T13:23:00.000-07:00

name Hagia Sophia Location Istanbul (historically Constantinople) Turkey

Designer Isidore of Miletus

Anthemius of Tralles

Type Museum (Current Use) / Imperial Mosque (Former) / Eastern Orthodox Church (Originally)

Material Ashlar, brick

Length 82 m (269 ft)

Width 73 m (240 ft)

Height 55 m (180 ft)

Beginning date 532 CE

Completion date 537 CE

Hagia Sophia (from the Greek: Ἁγία Σοφία, "Holy Wisdom"; Latin: Sancta Sophia or Sancta Sapientia) is a former Orthodox patriarchal basilica, later a mosque and now a museum in Istanbul, Turkey. From the date of its dedication in 360 until 1453, it served as the cathedral of Constantinople, except between 1204 and 1261, when it was the cathedral of the Latin empire. The building was a mosque from 29 May 1453 until 1934, when it was secularized. It was opened as a museum on 1 February 1935.[1]

Famous in particular for its massive dome, it is considered the epitome of Byzantine architecture and is said to have "changed the history of architecture."[2] It was the largest cathedral in the world for nearly a thousand years, until Seville Cathedral was completed in 1520. The current building was originally constructed as a church between 532 and 537 on the orders of the Byzantine Emperor Justinian and was the third Church of the Holy Wisdom to occupy the site, the previous two having both been destroyed by rioters. It was designed by Isidore of Miletus, a physicist, and Anthemius of Tralles, a mathematician.[3]

The church contained a large collection of holy relics and featured, among other things, a 49 feet (15 m) silver iconostasis. It was the seat of the Patriarch of Constantinople and the religious focal point of the Eastern Orthodox Church for nearly one thousand years. It was the church in which Cardinal Humbert in 1054 marched up to the altar and excommunicated Michael I Cerularius, which is commonly considered the start of the Great Schism.

In 1453, Constantinople was conquered by the Ottoman Turks and Sultan Mehmed II ordered the building to be converted into a mosque.[4] The bells, altar, iconostasis, and sacrificial vessels were removed and many of the mosaics were eventually plastered over. The Islamic features — such as the mihrab, the minbar, and the four minarets outside — were added over the course of its history under the Ottomans. It remained as a mosque until 1935, when it was converted into a museum by the Republic of Turkey.

For almost 500 years the principal mosque of Istanbul, Hagia Sophia served as a model for many other Ottoman mosques, such as the Sultan Ahmed Mosque (Blue Mosque of Istanbul), the Şehzade Mosque, the Süleymaniye Mosque, the Rüstem Pasha Mosque and the Kılıç Ali Paşa Mosque.

Although it is sometimes referred to as Sancta Sophia, as though it were named after a saint named Sophia (sophia being the phonetic spelling in Latin of the Greek word for wisdom), the full name in Greek is Ναός τῆς Ἁγίας τοῦ Θεοῦ Σοφίας, Church of the Holy Wisdom of God, the church being dedicated to Jesus Christ, in Eastern Orthodox theology, the Holy Wisdom of God

[edit] First church

The first church was known as the Μεγάλη Ἐκκλησία (Megálē Ekklēsíā, "Great Church"), or in Latin "Magna Ecclesia".[7] Inaugurated by Constantius II on 15 February 360, it was built next to the area where the imperial palace was being developed. The nearby Hagia Eirene ("Holy Peace") church was completed earlier and served as cathedral until the Hagia Sophia was completed. Both churches acted together as the principal churches of the Byzantine Empire.

The first church was chronicled by Socrates of Constantinople (380–440), who claimed that it was built by Constantine the Great. It was built as a traditional Latin colonnaded basilica with galleries and a wooden roof. It was preceded by an atrium. It was claimed to be one of the world's most outstanding monuments at the time.

The Patriarch of Constantinople John Chrysostom came into a conflict with Empress Aelia Eudoxia, wife of the emperor Arcadius, and was sent into exile on 20 June 404. During the subsequent riots, this first church was largely burned down. Nothing remains of the first church today.

[edit] Second church

Stone remains of the basilica ordered by Theodosius II, showing the Lamb of God

Marble blocks from the second churchA second church was ordered by Theodosius II, who inaugurated it on 10 October 415. The basilica with a wooden roof was built by architect Rufinus. A fire started during the tumult of the Nika Revolt burned the second Hagia Sophia to the ground on 13–14 January 532.

Several marble blocks from the second church survive to the present day. The blocks feature reliefs depicting 12 lambs — 12 apostles — among other remains. They were originally part of a monumental front entrance, and are now displayed in the garden of the current church. They were discovered in 1935 during an excavation of the western courtyard by A. M. Schneider. No further excavation works were undertaken for fear of harming the present Hagia Sophia building.

[edit] Third church (current structure)

Construction of church depicted in codex Manasses ChronicleOn 23 February 532, only a few days after the destruction of the second basilica, Emperor Justinian I took the decision to build a third and entirely different basilica, larger and more majestic than its predecessors.

Justinian chose the physicist Isidore of Miletus and the mathematician Anthemius of Tralles as architects; Anthemius, however, died within the first year. The construction is described by the Byzantine historian Procopius' On Buildings (Peri ktismatōn, Latin: De aedificiis). The emperor had material brought from all over the empire, such as Hellenistic columns from the Temple of Artemis at Ephesus. Large stones were brought from far-away quarries: porphyry from Egypt, green marble from Thessaly, black stone from the Bosporus region, and yellow stone from Syria. More than ten thousand people were employed during this construction. This new church was immediately recognized as a major work of architecture, demonstrating the creative insights of the architects. They may have used the theories of Heron of Alexandria to be able to construct a huge dome over such a large open space. The emperor, together with the patriarch Eutychius, inaugurated the new basilica on 27 December 537 with much pomp. The mosaics inside the church were, however, only completed under the reign of Emperor Justin II (565–578).

Depiction of the Hagia Sophia's appearance during Byzantine timesEarthquakes in August 553 and on 14 December 557 caused cracks in the main dome and the eastern half-dome to appear. The main dome collapsed completely during an earthquake on 7 May 558, destroying the ambon, the altar, and the ciborium over it. The emperor ordered an immediate restoration. He entrusted it to Isidorus the Younger, nephew of Isidore of Miletus. This time he used lighter materials and elevated the dome by 6.25 metres (20.5 ft), thus giving the building its current interior height of 55.6 metres (182 ft).[8] This reconstruction, giving the church its present sixth-century form, was completed in 562. The Byzantine poet Paul the Silentiary composed a long epic poem, still extant, known as Ekphrasis for the rededication of the basilica, presided over by Patriarch Eutychius, on 23 December 562.

Hagia Sophia was the seat of the Orthodox patriarch of Constantinople and a principal setting for Byzantine imperial ceremonies such as coronations. The basilica also offered asylum to wrongdoers. Foreign visitors were deeply impressed.

In 726 the emperor Leo the Isaurian issued a series of edicts against the veneration of images, ordering the army to destroy all icons, ushering in the period of Byzantine iconoclasm. At that time, all religious pictures and statues were removed from Hagia Sophia. After a brief reprieve under Empress Irene (797–802), the iconoclasts made a comeback. Emperor Theophilus (829–842) was strongly influenced by Islamic art,[citation needed] which forbids graven images. He had a two-winged bronze door with his monograms installed at the southern entrance of the church.

The basilica suffered damage, first in a great fire in 859, and again in an earthquake on 8 January 869 that made a half-dome collapse. Emperor Basil I ordered the church to be repaired.

After the great earthquake of 25 October 989, which ruined the great dome of Hagia Sophia, the Byzantine emperor Basil II asked for the Armenian architect Trdat, creator of the great churches of Ani and Agine, to repair the dome.[9] His main repairs were to the western arch and a portion of the dome. The extent of the church's destruction meant that reconstruction lasted six years. The church was re-opened on 13 May 994.

In his book De caerimoniis aulae Byzantinae ("Book of Ceremonies"), Emperor Constantine VII (913–919) wrote about all the details of the ceremonies held in Hagia Sophia by the emperor and the patriarch.

19th Century marker of the tomb of Enrico Dandolo, the Doge of Venice who commanded the Sack of Constantinople in 1204, inside the Hagia SophiaUpon the capture of Constantinople during the Fourth Crusade, the church was ransacked and desecrated by the Latin Christians. The Byzantine historian Niketas Choniates described the capture of Constantinople. Many reputed relics from the church, such as a stone from the tomb of Jesus, the Virgin Mary's milk, the shroud of Jesus, and bones of several saints, were sent to churches in the West and can be seen now in various museums in the West. During the Latin occupation of Constantinople (1204–1261) the church became a Roman Catholic cathedral. Baldwin I of Constantinople was crowned emperor on 16 May 1204 in Hagia Sophia, at a ceremony which closely followed Byzantine practices. Enrico Dandolo, the Doge of Venice who commanded the sack and invasion of the city by the Latin Crusaders in 1204, is buried inside the church. The tomb inscription carrying his name, which has become a part of the floor decoration, was spat upon by many of the angry Byzantines who recaptured Constantinople in 1261. However, restoration carried out during the period 1847–1849 cast doubt upon the authenticity of the doge's grave. It is more likely a symbolic burial site to keep alive his memory.

After the recapture in 1261 by the Byzantines, the church was in a dilapidated state. The four buttresses in the west were probably built during this time. In 1317, emperor Andronicus II ordered four new buttresses to be built in the eastern and northern parts of the church. After new cracks had developed in the dome after the earthquake of October 1344, several parts of the building collapsed on 19 May 1346. After that, the church remained closed until 1354, when repairs were undertaken by the architects Astras and Peralta.
Mosque

Fountain (Şadırvan) for ritual ablutions

The mihrab located in the apse where the altar used to stand, pointing towards MeccaImmediately after the Ottoman Turks conquered Constantinople in 1453, the Hagia Sophia was converted into the Ayasofya Mosque.[4] At that time, the church was very dilapidated. Several of its doors had fallen off. This condition was described by several Western visitors, such as the Córdoban nobleman Pero Tafur[10] and the Florentine Cristoforo Buondelmonti.[11] The sultan Mehmed II ordered the immediate cleanup of the church and its conversion to a mosque. The next sultan Bayezid II built a new minaret, replacing the one built by his father.

In the 16th century the sultan Suleiman the Magnificent (1520–1566) brought back two colossal candles from his conquest of Hungary. They were placed on both sides of the mihrab. During the reign of Selim II (1566–1577), the building started showing signs of fatigue and was extensively strengthened with the addition of structural supports to its exterior by the great Ottoman architect Mimar Sinan, who is also considered one of the world's first earthquake engineers.[12] In addition to strengthening the historic Byzantine structure, Sinan built the two additional large minarets at the western end of the building, the original sultan's loge, and the mausoleum of Selim II to the southeast of the building (then a mosque) in 1577. The mausoleums of Murad III and Mehmed III were built next to it in the 1600s.

Later additions were the sultan's gallery, a minbar decorated with marble, a dais for a sermon and a loggia for a muezzin.

The sultan Murad III (1574–1595) had two large alabaster Hellenistic urns transported from Pergamon and placed on two sides of the nave.

Sultan Mahmud I ordered the restoration of the building in 1739 and added a medrese (a Koranic school, now the library of the museum), a soup kitchen (for distribution to the poor) and a library, and in 1740 a fountain for ritual ablutions (Şadirvan), thus transforming it into a külliye, i.e. a social complex. At the same time a new sultan's gallery and a new mihrab were built inside.

The most famous restoration of the Hagia Sophia was ordered by Sultan Abdülmecid and completed by eight hundred workers between 1847 and 1849, under the supervision of the Swiss-Italian architect brothers Gaspare and Giuseppe Fossati. The brothers consolidated the dome and vaults, straightened the columns, and revised the decoration of the exterior and the interior of the building. The mosaics in the upper gallery were cleaned. The old chandeliers were replaced by new pendant ones. New gigantic circular-framed disks or medallions were hung on columns. They were inscribed with the names of Allah, the Prophet Muhammad, the first four caliphs Abu Bakr, Umar, Uthman and Ali, and the two grandchildren of Mohammed: Hassan and Hussain, by the calligrapher Kazasker İzzed Effendi (1801–1877). In 1850 the architect Fossati built a new sultan's gallery in a Neo-Byzantine style connected to the royal pavilion behind the mosque. Outside the Hagia Sophia, a timekeeper's building and a new madrasah were built. The minarets were altered so that they were of equal height. When the restoration was finished, the mosque was re-opened with ceremonial pomp on 13 July 1849.

Great Wall of China

2010-05-18T12:33:00.000-07:00

State Party China

Type Cultural

Criteria i, ii, iii, iv, vi

Reference 438

Region** Asia-Pacific

The Great Wall of China (simplified Chinese: 长城; traditional Chinese: 長城; pinyin: Chángchéng; literally "long fortress" or simplified Chinese: 万里长城; traditional Chinese: 萬里長城; pinyin: Wànlǐ Chángchéng; literally "The long wall of 10,000 Li (里)"[1]) is a series of stone and earthen fortifications in northern China, built originally to protect the northern borders of the Chinese Empire against intrusions by various nomadic groups such as the Xiongnu from the north and rebuilt and maintained between the 5th century BC and the 16th century. Since the 5th century BC, several walls have been built that were referred to as the Great Wall. One of the most famous is the wall built between 220–206 BC by the first Emperor of China, Qin Shi Huang. Little of that wall remains; the majority of the existing wall was built during the Ming Dynasty.

History

Great Wall of the Qin Dynasty

Great Wall of the Han Dynasty

Great Wall of the Ming Dynasty

Map of the whole wall constructionsThe Chinese were already familiar with the techniques of wall-building by the time of the Spring and Autumn Period, which began around the 8th century BC. During the Warring States Period from the 5th century BC to 221 BC, the states of Qi, Yan and Zhao all constructed extensive fortifications to defend their own borders. Built to withstand the attack of small arms such as swords and spears, these walls were made mostly by stamping earth and gravel between board frames. Qin Shi Huang conquered all opposing states and unified China in 221 BC, establishing the Qin Dynasty. Intending to impose centralized rule and prevent the resurgence of feudal lords, he ordered the destruction of the wall sections that divided his empire along the former state borders. To protect the empire against intrusions by the Xiongnu people from the north, he ordered the building of a new wall to connect the remaining fortifications along the empire's new northern frontier. Transporting the large quantity of materials required for construction was difficult, so builders always tried to use local resources. Stones from the mountains were used over mountain ranges, while rammed earth was used for construction in the plains. There are no surviving historical records indicating the exact length and course of the Qin Dynasty walls. Most of the ancient walls have eroded away over the centuries, and very few sections remain today. Later, the Han, Sui, Northern and Jin dynasties all repaired, rebuilt, or expanded sections of the Great Wall at great cost to defend themselves against northern invaders.

The Great Wall concept was revived again during the Ming Dynasty following the Ming army's defeat by the Oirats in the Battle of Tumu in 1449. The Ming had failed to gain a clear upper-hand over the Manchurian and Mongolian tribes after successive battles, and the long-drawn conflict was taking a toll on the empire. The Ming adopted a new strategy to keep the nomadic tribes out by constructing walls along the northern border of China. Acknowledging the Mongol control established in the Ordos Desert, the wall followed the desert's southern edge instead of incorporating the bend of the Huang He.

Photograph of the Great Wall in 1907Unlike the earlier Qin fortifications, the Ming construction was stronger and more elaborate due to the use of bricks and stone instead of rammed earth. As Mongol raids continued periodically over the years, the Ming devoted considerable resources to repair and reinforce the walls. Sections near the Ming capital of Beijing were especially strong.[citation needed]

During the 1440s–1460s, the Ming also built a so-called "Liaodong Wall". Similar in function to the Great Wall (whose extension, in a sense, it was), but more basic in construction, the Liaodong Wall enclosed the agricultural heartland of the Liaodong province, protecting it against potential incursions by Jurched-Mongol Oriyanghan from the northwest and the Jianzhou Jurchens from the north. While stones and tiles were used in some parts of the Liaodong Wall, most of it was in fact simply an earth dike with moats on both sides.[5]

Towards the end of the Ming Dynasty, the Great Wall helped defend the empire against the Manchu invasions that began around 1600. Under the military command of Yuan Chonghuan, the Ming army held off the Manchus at the heavily fortified Shanhaiguan pass, preventing the Manchus from entering the Chinese heartland. The Manchus were finally able to cross the Great Wall in 1644, when the gates at Shanhaiguan were opened by Wu Sangui, a Ming border general who disliked the activities of rulers of the Shun Dynasty. The Manchus quickly seized Beijing, and defeated the newly founded Shun Dynasty and remaining Ming resistance, to establish the Qing Dynasty.

In 2009, an additional 290 kilometres (180 miles) of previously undetected portions of the wall, built during the Ming Dynasty, were discovered. The newly discovered sections range from the Hushan mountains in the northern Liaoning province to Jiayuguan in western Gansu province. The sections had been submerged over time by sandstorms that moved across the arid region.[6]

Under Qing rule, China's borders extended beyond the walls and Mongolia was annexed into the empire, so construction and repairs on the Great Wall were discontinued.

Notable areas

An area of the sections of the Great Wall at Jinshanling

The Great WallSome of the following sections are in Beijing municipality, which were renovated and which are regularly visited by modern tourists today.

"North Pass" of Juyongguan pass, known as the Badaling. When used by the Chinese to protect their land, this section of the wall has had many guards to defend China’s capital Beijing. Made of stone and bricks from the hills, this portion of the Great Wall is 7.8 meters (25.6 ft) high and 5 meters (16.4 ft) wide.

"West Pass" of Jiayuguan (pass). This fort is near the western edges of the Great Wall.

"Pass" of Shanhaiguan. This fort is near the eastern edges of the Great Wall.

One of the most striking sections of the Ming Great Wall is where it climbs extremely steep slopes. It runs 11 kilometers (7 mi) long, ranges from 5 to 8 meters (16–26 ft) in height, and 6 meters (19.7 ft) across the bottom, narrowing up to 5 meters (16.4 ft) across the top. Wangjinglou is one of Jinshanling's 67 watchtowers, 980 meters (3,215 ft) above sea level.

South East of Jinshanling, is the Mutianyu Great Wall which winds along lofty, cragged mountains from the southeast to the northwest for approximately 2.25 kilometers (about 1.3 miles). It is connected with Juyongguan Pass to the west and Gubeikou to the east.

25 km west of the Liao Tian Ling stands apart of Great Wall which is only 2~3 stories high. According to the records of Lin Tian, the wall was not only extremely short compared to others, but it appears to be silver. Archeologists explain that the wall appears to be silver because the stone they used were from Shan Xi, where many mines are found. The stone contains extremely high metal in it causing it to appear silver. However, due to years of decay of the Great Wall, it is hard to see the silver part of the wall today.

Another notable section lies near the eastern extremity of the wall, where the first pass of the Great Wall was built on the Shanhaiguan (known as the “Number One Pass Under Heaven”), the first mountain the Great Wall climbs. Jia Shan is also here, as is the Jiumenkou, which is the only portion of the wall that was built as a bridge.

Characteristics

The Great Wall on an 1805 mapBefore the use of bricks, the Great Wall was mainly built from rammed earth, stones, and wood.

During the Ming Dynasty, however, bricks were heavily used in many areas of the wall, as were materials such as tiles, lime, and stone. The size and weight of the bricks made them easier to work with than earth and stone, so construction quickened. Additionally, bricks could bear more weight and endure better than rammed earth. Stone can hold under its own weight better than brick, but is more difficult to use. Consequently, stones cut in rectangular shapes were used for the foundation, inner and outer brims, and gateways of the wall. Battlements line the uppermost portion of the vast majority of the wall, with defensive gaps a little over 30 cm (one foot) tall, and about 23 cm (9 inches) wide.

Condition

The Great Wall at Mutianyu, near Beijing

The Great Wall in fogWhile some portions north of Beijing and near tourist centers have been preserved and even extensively renovated, in many locations the Wall is in disrepair. Those parts might serve as a village playground or a source of stones to rebuild houses and roads.[7] Sections of the Wall are also prone to graffiti and vandalism. Parts have been destroyed because the Wall is in the way of construction.[8]

More than 60 kilometres (37 mi) of the wall in Gansu province may disappear in the next 20 years, due to erosion from sandstorms. In places, the height of the wall has been reduced from more than five meters (16.4 ft) to less than two meters. The square lookout towers that characterize the most famous images of the wall have disappeared completely. Many western sections of the wall are constructed from mud, rather than brick and stone, and thus are more susceptible to erosion.[9]

Watchtowers and barracks

WatchtowerCommunication between the army units along the length of the Great Wall, including the ability to call reinforcements and warn garrisons of enemy movements, was of high importance. Signal towers were built upon hill tops or other high points along the wall for their visibility.

Naked-eye viewing from high altitudes

Visibility from the moon

Popular beliefs ranging from Ripley's Believe It or Not!'s cartoons from 1930s, which claimed that the Great Wall is "the mightiest work of man, the only one that would be visible to the human eye from the moon," to Richard Halliburton's 1938 book Second Book of Marvels which makes a similar claim, have persisted, assuming urban legend status, and sometimes even appearing in school textbooks. Arthur Waldron, author of The Great Wall of China: From History to Myth, has speculated that the belief might go back to the fascination with the "canals" once believed to exist on Mars.

One of the earliest known references to this myth appears in a letter written in 1754 by the English antiquary William Stukeley. Stukeley wrote that, "This mighty wall of four score miles in length (Hadrian's Wall) is only exceeded by the Chinese Wall, which makes a considerable figure upon the terrestrial globe, and may be discerned at the moon."[10]

The Great Wall is a maximum 9.1 m (30 ft) wide and is about the same color as the soil surrounding it. Based on the optics of resolving power (distance versus the width of the iris: a few millimetres for the human eye, metres for large telescopes) only an object of reasonable contrast to its surroundings 70 miles or more in diameter (1 arc-minute) would be visible to the unaided eye from the moon, whose average distance from Earth is 384,393 km (238,857 miles). The apparent width of the Great Wall from the moon is the same as that of a human hair viewed from 2 miles away. To see the wall from the moon would require spatial resolution 17,000 times better than normal (20/20) vision.[11] Unsurprisingly, no lunar astronaut has ever claimed seeing the Great Wall from the moon.

Visibility from low earth orbit

A more controversial question is whether the Wall is visible from low earth orbit, i.e., an altitude of as little as 100 miles (160 km). NASA claims that it is barely visible, and only under nearly perfect conditions; it is no more conspicuous than many other man-made objects.[12] Other authors have argued that due to limitations of the optics of the eye and the spacing of photoreceptors on the retina, it is impossible to see the wall with the naked eye, even from low orbit, and would require visual acuity of 20/3 (7.7 times better than normal).[11]

Anecdotal reports

Astronaut William Pogue thought he had seen it from Skylab but discovered he was actually looking at the Grand Canal of China near Beijing. He spotted the Great Wall with binoculars, but said that "it wasn't visible to the unaided eye." U.S. Senator Jake Garn claimed to be able to see the Great Wall with the naked eye from a space shuttle orbit in the early 1980s, but his claim has been disputed by several U.S. astronauts. Veteran U.S. astronaut Gene Cernan has stated: "At Earth orbit of 100 miles (160 km) to 200 miles (320 km) high, the Great Wall of China is, indeed, visible to the naked eye." Ed Lu, Expedition 7 Science Officer aboard the International Space Station, adds that, "it's less visible than a lot of other objects. And you have to know where to look."

Neil Armstrong stated about the view from Apollo 11: "I do not believe that, at least with my eyes, there would be any man-made object that I could see. I have not yet found somebody who has told me they've seen the Wall of China from Earth orbit. ...I've asked various people, particularly Shuttle guys, that have been many orbits around China in the daytime, and the ones I've talked to didn't see it."[13]

Topographic maps put together showing the location of the eastern parts of the wall between the Yellow River and the Bohai Sea.In October 2003, Chinese astronaut Yang Liwei stated that he had not been able to see the Great Wall of China. In response, the European Space Agency (ESA) issued a press release reporting that from an orbit between 160 and 320 km, the Great Wall is visible to the naked eye. In an attempt to further clarify things, the ESA published a picture of a part of the “Great Wall” photographed from Space. However, in a press release a week later (no longer available in the ESA’s website), they acknowledged that the "Great Wall" in the picture was actually a river.[11]

Leroy Chiao, a Chinese-American astronaut, took a photograph from the International Space Station that shows the wall. It was so indistinct that the photographer was not certain he had actually captured it. Based on the photograph, the China Daily later reported that the Great Wall can be seen from space with the naked eye, under favorable viewing conditions, if one knows exactly where to look.[14] However, the resolution of a camera can be much higher than the human visual system, and the optics much better, rendering photographic evidence irrelevant to the issue of whether it is visible to the naked eye

The Great Wall stretches from Shanhaiguan in the east to Lop Nur in the west, along an arc that roughly delineates the southern edge of Inner Mongolia. The most comprehensive archaeological survey, using advanced technologies, has recently concluded that the entire Great Wall, with all of its branches, stretches for 8,851.8 km (5,500.3 mi). This is made up of 6,259.6 km (3,889.5 mi) of sections of actual wall, 359.7 km (223.5 mi) of trenches and 2,232.5 km (1,387.2 mi) of natural defensive barriers such as hills and rivers

Thiruvalluvar

2010-05-18T11:47:00.000-07:00

Name- Thiruvalluvar

wife name- Vasuki

Thiruvalluvar (Tamil: திருவள்ளுவர்) is a celebrated Tamil poet who wrote the Thirukkural, a work on ethics in Tamil literature. He is also known by other names like Theiva Pulavar and Poyyamozhi Pulavar.

The time period of Thiruvalluvar's existence has been based on mostly linguistic evidences rather than archeological evidences since none such has been determined. His period has been estimated to be between 100 BC and 600 AD.[citation needed]

Contents [hide]

Traditional accounts

Most of the Researchers and great Tamil Scholars like George Uglow Pope or G.U. Pope who had spent many years in Tamil Nadu and translated many Tamil texts into English, which includes Thirukkural, have recognised Thiruvalluvar as a Paraiyar. Karl Graul (1814–1864) had already by 1855 characterized the Tirukkural as 'a work of Buddhist hue'. In this connection it was then of particular interest that Thiruvalluvar, the author of the Tirukkural was identified as a Paraiyar in Tamil tradition (as, incidentally, were also other famous ancient Tamil writers, e.g., Auvaiyar ; cf. Pope 1886: i–ii, x–xi). It should be noted that Graul could have been subsuming the Jains also under the name of the Buddhists (Graul 1865: xi note). The name Valluvan was/is a common name representing his caste/occupation rather than his proper name. However, the question of whether the author of Thirukkural (Valluvan) is named after his community or vice versa remains unanswered.

The name Thiruvalluvar (ThiruValluvar) consists of Thiru (a Tamil word meaning honorable, similar to Mr)[1] and Valluvar (a polite name for Valluvan, according to Tamil tradition). There are a few legends about the birth of Thiruvalluvar. The Saiva, Vaishnava, Jaina, Buddhist and even Christian denominations contend that Thiruvalluvar belongs to their school. The work does begin with a chapter Saluting the Almightly. So Thiruvalluvar was a theist. But his God is Almighty, creator of all the worlds, and who delivers those who throw themselves at his feet. The Kural per se does not advocate any specific or sectarian religious faith. One legend associates him to Madurai, the ancient capital of the Pandya rulers who vigorously promoted Tamil literature. According to another he was born and lived in Mylapore, a part of present day Chennai city and traveled to Madurai to submit his work, the Thirukural, for approval of the king (Pandian) and his college of poets. His wife is named Vasuki.[2]

There are, also, more traditional stories citing the Tamil Sangam of Madurai (the assembly/conference of eminent scholars and researchers conducted on a regular basis) as the authority through which Thirukkural was introduced to the world. Thiruvalluvar might have spent most part of his life in Madurai because it was under the Pandia rulers that many Tamil poets flourished. There is also the recent claim by Kanyakumari Historical and Cultural Research Centre (KHCRC) that Valluvar was a king who ruled Valluvanadu in the hilly tracts of Kanyakumari District of Tamil Nadu.[3]

Thirukkural

Tiruvalluvar statue in KanyakumariMain article: ThirukkuralThirukkural is one of most revered ancient works in the Tamil [4] . Kural is considered as 'World common faith'[citation needed], as it shows the way for human morals and betterment in life. The Kural has been translated into most languages, likely next only to the Bible, Qur'an and Gita .[citation needed]. The Latin translation of Thirukkural made by Constanzo Beschi in 1730 helped significantly to make known to European intellectuals the richness and beauty of Tamil literature.

Thirukkural is a combined word formed by joining the two words Thiru and Kural, i.e. Thiru + Kural = Thirukkural.

Thirukkural is divided into three sections. Section one deals with Aram, good ethical behavior with conscience and honor ("right conduct"), Section two discusses Porul, the right manner of conducting worldly affairs, and Section three dwells on Inbam, love between man and woman. The First section has 38 chapters, Second has 70 chapters and the Third 25 chapters. Each Chapters consists of 10 couplets or kurals thus making 1330 couplets in total.

There is a 133 feet tall statue of Saint Thiruvalluvar erected at the southern tip of Indian subcontinent (Kanyakumari) where the Arabian Sea, the Bay of Bengal, and the Indian Ocean converge. The 133 ft denotes Thirukkural's 133 Chapters or athikarams and the show of three fingers denote the three themes Aram, Porul, and Inbam ie the Sections on Morals, Wealth and Love.

sahara desert

2010-05-18T11:31:00.000-07:00

sahara desert

Desertification is a complex process and is a result of activities such. overgrazing, poor irrigation systems and deforestation. It is most common in the Sahel region of Africa, which is a piece of land in the southern end of Sahara desert. Sahara grows p.g.a. Desertification, and the process can only be reversed by being made to change the way you grow agriculture and by replant forests. Sahara desert is now about 5000 km. wide and 2000 km. long, which roughly corresponds to the size of the U.S..

Sahara is an Arabic word meaning "emptiness" or "nothing". But it has not always been so. For ten thousand years ago Sahara was a big, lush savannah. But nomads drove the exploitation of the green plains with their cattle, and the plains were turned into deserts. Sahara is the hottest and driest place on earth, but the nights can be icy cold.

And unlike what one might think, there's life in the Sahara. The desert landscape sponsoring heat conceals a dreamlike world of strange animals in some strange way have learned to adapt and not found anywhere else. From the diminutive ørkenræv with the big ears and its arch-rival sand cat, the world's smallest wild cat. For the most toxic long, strong tiger beetle, the graceful and beautiful dorcasgazelle ørkenlos and his worst competitor; eagle.

Except for the few days a year where the famous Paris-Dakar motorcycle races are held and Shahara therefore is filled with motorcycles and trucks are the preferred mode of transport still to this day camel and there are also still nomads and caravan. They travel thousands of miles through the desert and is vital for desert dwellers. Millet, dates, and especially salt are the most coveted commodities.

Every day the caravan on the road for 18 hours - otherwise, will betray give out. 60 km a day traveling it. Everything takes place in time - even tebrygning and cooking. Once darkness had fallen, navigating officer on the stars, and only 11 o'clock in the evening can start the caravan to camp. Caravan is frequently at the mercy of the driver's mercy. If he becomes ill during the trip, the caravan is lost, because only he can navigate through the uniform desert landscape.

Other deserts

A desert is the designation for rural areas with low rainfall but high temperatures and evaporation. The vegetation is very frugal, or not present. The most famous deserts are the Sahara, Kalahari, Gobi and Death Valley. These are all hot, dry areas, but there are also other types of desert.

It runs a huge coherent desert through the Sahara to the Arabian peninsula to the south of Iran and Pakistan. Other desert areas in the western United States, at the South American Pacific Coast, in Namibia and the western and central parts of Australia. Gobi Desert in Mongolia occupies a special position in relation to the others in that it lies between 35 and 50 º north.

Some deserts because the soil is toxic to plants. In particular, a high content of salt kill vegetation. Salt Deserts can occur if you use seawater for irrigation. There are also deserts in the Arctic. Here it is temperature rather than lack of water, limiting vegetation.

SALT desert

SAND desert

In a desert precipitation is typically much less than potential evaporation. This means that the temperature will rise during the day and fall at night. Water has a high heat capacity and can thus contain much energy, so if there is much water in an area will the temperature difference between night and day can be lower. The limited rainfall in a desert means that there will not be enough water to reduce temperature fluctuations, and there will not be enough water for effective photosynthesis. Therefore there will be limited vegetation and large temperature differences between night and day.

Plants absorb energy from the sun for photosynthesis through some openings, called stomata (stomata). When the temperature of the stomata becomes too high, they closed and photosynthesis stops. To keep the temperature down (and photosynthesis in time) the plant will try to draw water up from the ground by the roots and up to stomata, where it then evaporates, and thereby cools the plant.

With cactus absorbed CO2 through stomata at night, after which they can be kept closed during the day. It reduces fluid requirements dramatically, and allows cacti to grow in desert areas where other plants may give up. Since there was therefore no basis for agriculture in deserts, most cultures nomadic desert societies, however, with a few isolated urban culture based on commerce.

Eiffel Tower

2010-05-18T08:27:00.000-07:00

General information
Eiffel Tower was the world's tallest building from 1889 to 1930.^[I]
Location	Paris, France
Coordinates	48°51′30″N 2°17′40″E / 48.8583°N 2.2945°E / 48.8583; 2.2945Coordinates: 48°51′30″N 2°17′40″E / 48.8583°N 2.2945°E / 48.8583; 2.2945
Status	Complete

Height
Constructed	1887–1889
Opening	March 31, 1889
Use	Observation tower, Radio broadcasting tower
Antenna or spire	324.00 m (1,063 ft)
Roof	300.65 m (986 ft)
Top floor	273.00 m (896 ft)
Technical details
Floor count	3
Elevators	7
Companies involved
Architect(s)	Stephen Sauvestre
Structural engineer	Maurice Koechlin, Emile Nouguier
Contractor	Gustave Eiffel & Cie
Owner	City of Paris, France (100%)
Management	Société d’Exploitation de la Tour Eiffel (SETE)
References: ^[1]^[2]^[3]^[4]^[5]^[6]^[7]^[8]^[9]
^ Fully habitable, self-supported, from main entrance to highest structural or architectural top; see the list of tallest buildings in the world for other listings.

The Eiffel Tower (French: Tour Eiffel, [tuʁ ɛfɛl]) is an 1889 iron lattice tower located on the Champ de Mars in Paris that has become both a global icon of France and one of the most recognizable structures in the world. The Eiffel Tower, which is the tallest building in Paris,^[10] is the single most visited paid monument in the world; millions of people ascend it every year. Named after its designer, engineer Gustave Eiffel, the tower was built as the entrance arch for the 1889 World's Fair.
The tower stands 324 m (1,063 ft) tall, about the same height as an 81-story building. It was the tallest man-made structure in the world from its completion until the Chrysler Building in New York City was built in 1930. Not including broadcast antennas, it is the second-tallest structure in France after the 2004 Millau Viaduct.
The tower has three levels for visitors. Tickets can be purchased to ascend by stairs or lift to the first and second levels. The walk to the first level is over 300 steps, as is the walk from the first to the second level. The third and highest level is accessible only by lift. Both the first and second levels feature restaurants.
The tower has become the most prominent symbol of both Paris and France, often in the establishing shot of films set in the city.

History

Eiffel Tower under construction in July 1888

Stages of construction of the Eiffel Tower

The structure was built between 1887 and 1889 as the entrance arch for the Exposition Universelle, a World's Fair marking the centennial celebration of the French Revolution. Three hundred workers joined together 18,038 pieces of puddled iron (a very pure form of structural iron), using two and a half million rivets, in a structural design by Maurice Koechlin. The co-architects of the Eiffel Tower were Emile Nouguier, Maurice Koechlin and Stephen Sauvestre.^[11] The risk of accident was great as, unlike modern skyscrapers, the tower is an open frame without any intermediate floors except the two platforms. However, because Eiffel took safety precautions, including the use of movable stagings, guard-rails and screens, only one man died. The tower was inaugurated on 31 March 1889, and opened on 6 May.
The tower was much criticised by the public when it was built, with many calling it an eyesore. Newspapers of the day were filled with angry letters from the arts community of Paris. One is quoted extensively in William Watson's US Government Printing Office publication of 1892 Paris Universal Exposition: Civil Engineering, Public Works, and Architecture: “And during twenty years we shall see, stretching over the entire city, still thrilling with the genius of so many centuries, we shall see stretching out like a black blot the odious shadow of the odious column built up of riveted iron plates.”^[12] Signers of this letter included Jean-Louis-Ernest Meissonier, Charles Gounod, Charles Garnier, Jean-Léon Gérôme, William-Adolphe Bouguereau, and Alexandre Dumas.
Novelist Guy de Maupassant—who claimed to hate the tower^[13]—supposedly ate lunch in the Tower's restaurant every day. When asked why, he answered that it was the one place in Paris where one could not see the structure. Today, the Tower is widely considered^{[by whom?]} to be a striking piece of structural art.
One of the great Hollywood movie clichés is that the view from a Parisian window always includes the tower. In reality, since zoning restrictions limit the height of most buildings in Paris to 7 stories, only a very few of the taller buildings have a clear view of the tower.
Eiffel had a permit for the tower to stand for 20 years; it was to be dismantled in 1909, when its ownership would revert to the City of Paris. The City had planned to tear it down (part of the original contest rules for designing a tower was that it could be easily demolished) but as the tower proved valuable for communication purposes, it was allowed to remain after the expiry of the permit. The military used it to dispatch Parisian taxis to the front line during the First Battle of the Marne.

Timeline of events

10 September 1889: Thomas Edison visited the tower. He signed the guestbook with the following message—

To M Eiffel the Engineer the brave builder of so gigantic and original specimen of modern Engineering from one who has the greatest respect and admiration for all Engineers including the Great Engineer the Bon Dieu, Thomas Edison.

1910: Father Theodor Wulf measured radiant energy at the top and bottom of the tower, discovering at the top more than was expected, and thereby detecting what are today known as cosmic rays.^[14]
4 February 1912: Austrian tailor Franz Reichelt died after jumping 60 metres from the first deck of Eiffel tower with his home-made parachute.
1925: The con artist Victor Lustig "sold" the tower for scrap metal on two separate, but related occasions.^[15]
1930: The tower lost the title of the world's tallest structure when the Chrysler Building was completed in New York City.
1925 to 1934: Illuminated signs for Citroën adorned three of the tower's four sides, making it the tallest advertising space in the world at the time.
1940-1944: Upon the German occupation of Paris in 1940, the lift cables were cut by the French so that Adolf Hitler would have to climb the steps to the summit. The parts to repair them were allegedly impossible to obtain because of the war. In 1940 German soldiers had to climb to the top to hoist the swastika, but the flag was so large it blew away just a few hours later, and was replaced by a smaller one. When visiting Paris, Hitler chose to stay on the ground. It was said that Hitler conquered France, but did not conquer the Eiffel Tower. A Frenchman scaled the tower during the German occupation to hang the French flag. In August 1944, when the Allies were nearing Paris, Hitler ordered General Dietrich von Choltitz, the military governor of Paris, to demolish the tower along with the rest of the city. Von Choltitz disobeyed the order. The lifts of the Tower were working normally within hours of the Liberation of Paris.
3 January 1956: A fire damaged the top of the tower.
1957: The present radio antenna was added to the top.
1980s: A restaurant and its supporting iron scaffolding midway up the tower was dismantled; it was purchased and reconstructed on St. Charles Avenue and Joesphine Street in Garden District of New Orleans, Louisiana, by entrepreneurs John Onorio and Daniel Bonnot, originally as the Tour Eiffel Restaurant, later as the Red Room and now as the Cricket Club (owned by the New Orleans Culinary Institute). The restaurant was re-assembled from 11,000 pieces that crossed the Atlantic in a 40-foot (12 m) cargo container.
31 March 1984: Robert Moriarty flew a Beechcraft Bonanza through the arches of the tower.^[16]
1987: A.J. Hackett made one of his first bungee jumps from the top of the Eiffel Tower, using a special cord he had helped develop. Hackett was arrested by the Paris police upon reaching the ground.^[17]
14 July 1995: Bastille Day, French synthesiser musician Jean Michel Jarre performed Concert For Tolerance at the tower in aid of UNESCO. The free concert was attended by an estimated 1.5 million people, filling the Champ de Mars. The concert featured lighting and projection effects on the tower, and a huge fireworks display throughout. Three years later he returned to the same spot for a more dance music-oriented show, Electronic Night.
New Year's Eve 1999: The Eiffel Tower played host to Paris' Millennium Celebration. Fireworks were set off all over the tower. An exhibition above a cafeteria on the first floor commemorates this event.
2000: Flashing lights and four high-power searchlights were installed on the tower. Since then the light show has become a nightly event. The searchlights on top of the tower make it a beacon in Paris' night sky.
2002: The tower received its 200,000,000th guest.^[18]^[19]
22 July 2003: At 19:20, a fire occurred at the top of the tower in the broadcasting equipment room. The entire tower was evacuated; the fire was extinguished after 40 minutes, and there were no reports of injuries.
2004: The Eiffel Tower began hosting an ice skating rink on the first floor each winter.^[20]
2008: At the start of the French presidency of the European Union in the second half of 2008, the twelve golden stars of the European flag were mounted on the base, and whole tower bathed in blue light. In addition, every hour on the hour, 20,000 flash bulbs give the tower a sparkly appearance.^[21]

Engraved names

Main article: The 72 names on the Eiffel Tower

Gustave Eiffel engraved on the tower seventy-two names of French scientists, engineers and other notable people. This engraving was painted over at the beginning of the twentieth century but restored in 1986–1987 by the Société Nouvelle d'exploitation de la Tour Eiffel, a company contracted to operate business related to the Tower.

Design of the tower

Material

The metal structure of the Eiffel Tower weighs 7,300 tonnes while the entire structure, including non-metal components, is approximately 10,000 tonnes. As a demonstration of the economy of design, if the 7,300 tonnes of the metal structure were melted down it would fill the 125 metre square base to a depth of only 6 cm (2.36 in), assuming the density of the metal to be 7.8 tonnes per cubic metre. Depending on the ambient temperature, the top of the tower may shift away from the sun by up to 18 cm (7.1 in) because of thermal expansion of the metal on the side facing the sun.

The third floor of the Eiffel Tower, at night, seen from Trocadéro

The Eiffel Tower from the Left Bank

Wind considerations

At the time the tower was built many people were shocked by its daring shape. Eiffel was criticised for the design and accused of trying to create something artistic, or inartistic according to the viewer, without regard to engineering. Eiffel and his engineers, however, as experienced bridge builders, understood the importance of wind forces and knew that if they were going to build the tallest structure in the world they had to be certain it would withstand the wind. In an interview reported in the newspaper Le Temps, Eiffel said:

Now to what phenomenon did I give primary concern in designing the Tower? It was wind resistance. Well then! I hold that the curvature of the monument's four outer edges, which is as mathematical calculation dictated it should be [...] will give a great impression of strength and beauty, for it will reveal to the eyes of the observer the boldness of the design as a whole.^[22]

The shape of the tower was determined by empirical methods accounting for the effects of wind, and graphical methods, without an overall mathematical framework. Careful examination of the tower shows a basically exponential shape; actually two different exponentials, the lower section overdesigned to ensure resistance to wind forces.
Several explanations have been proposed over the years; the most recent is a nonlinear integral equation based on counterbalancing the wind pressure on any point on the tower with the tension between the construction elements at that point.^[23]^[24] The tower sways 6–7 cm (2–3 in) in the wind.^[25]

Maintenance

Maintenance of the tower includes applying 50 to 60 tonnes of paint every seven years to protect it from rust.

Aesthetic considerations

In order to maintain a uniform appearance to an observer on the ground, three separate colors of paint are used on the tower, with the darkest on the bottom and the lightest at the top. On occasion the colour of the paint is changed; the tower is currently painted a shade of brownish-grey.^[26] On the first floor there are interactive consoles hosting a poll for the colour to use for a future session of painting.
The only non-structural elements are the four decorative grillwork arches, added in Stephen Sauvestre's sketches, which served to reassure visitors that the structure was safe, and to frame views of other nearby architecture.^[27]^[28]^[29]

Tourism

Popularity

More than 200,000,000 people have visited the tower since its construction in 1889,^[30] including 6,719,200 in 2006.^[25] The tower is the most-visited paid monument in the world.^[31]^[32]

Passenger lifts

The Eiffel Tower, October 2007

Ground to the second level

The original lifts to the first and second floors were provided by two companies. Both companies had to overcome many technical obstacles as neither company (or indeed any company) had experience with installing lifts climbing to such heights with large loads. The slanting tracks with changing angles further complicated the problems. The East and West lifts were supplied by the French company Roux Combaluzier Lepape, using hydraulically powered chains and rollers. Contemporary engravings of the lift cars show that the passengers were seated at this time but it is not clear whether this was conceptual. It would be unnecessary to seat passengers for a journey of a couple of minutes. The North and South lifts were provided by the American Otis company using car designs similar to the original installation but using an improved hydraulic and cable scheme. The French lifts had a very poor performance and were replaced with the current installations in 1897 (West Pillar) and 1899 (East Pillar) by Fives-Lille using an improved hydraulic and rope scheme. Both of the original installations operated broadly on the principle of the Fives-Lille lifts.^[33]^[34]
The Fives-Lille lifts from ground level to the first and second levels are operated by cables and pulleys driven by massive water-powered pistons. The hydraulic scheme was somewhat unusual for the time in that it included three large counterweights of 200 tonnes each sitting on top of hydraulic rams which doubled up as accumulators for the water. As the lifts ascend the inclined arc of the pillars, the angle of ascent changes. The two lift cabs are kept more or less level and indeed are level at the landings. The cab floors do take on a slight angle at times between landings.

The Eiffel Tower illuminated in blue to celebrate the French presidency of the EU (July 2008)

The principle behind the lifts is similar to the operation of a block and tackle but in reverse. Two large hydraulic rams (over 1 metre diameter) with a 16 metre travel are mounted horizontally in the base of the pillar which pushes a carriage (the French word for it translates as chariot and this term will be used henceforth to distinguish it from the lift carriage) with 16 large triple sheaves mounted on it. There are 14 similar sheaves mounted statically. Six wire ropes are rove back and forth between the sheaves such that each rope passes between the 2 sets of sheaves 7 times. The ropes then leave the final sheaves on the chariot and passes up through a series of guiding sheaves to above the second floor and then via a pair of triple sheaves back down to the lift carriage again passing guiding sheaves.
This arrangement means that the lift carriage, complete with its cars and passengers, travels 8 times the distance that the rams move the chariot, the 128 metres from the ground to the second floor. The force exerted by the rams also has to be 8 times the total weight of the lift carriage, cars and passengers, plus extra to account for various losses such as friction. The hydraulic fluid was water, normally stored in three accumulators, complete with counterbalance weights. To make the lift ascend, water was pumped using an electrically driven pump from the accumulators to the two rams. Since the counterbalance weights provided much of the pressure required, the pump only had to provide the extra effort. For the descent, it was only necessary to allow the water to flow back to the accumulators using a control valve. The lifts were operated by an operator perched precariously underneath the lift cars. His position (with a dummy operator) can still be seen on the lifts today.
The Fives-Lille lifts were completely upgraded in 1986 to meet modern safety requirements and to make the lifts easier to operate. A new computer controlled system was installed which completely automated the operation. One of the three counterbalances was taken out of use, and the cars were replaced with a more modern and lighter structure. Most importantly, the main driving force was removed from the original water pump such that the water hydraulic system provided only a counterbalancing function. The main driving force was transferred to a 320 kW electrically driven oil hydraulic pump which drives a pair of hydraulic motors on the chariot itself thus providing the motive power. The new lift cars complete with their carriage and a full 92 passenger load weigh 22 tonnes.

A view from above

Due to elasticity in the ropes and the time taken to get the cars level with the landings, each lift in normal service takes an average of 8 minutes and 50 seconds to do the round trip spending an average of 1 minute and 15 seconds at each floor. The average journey time between floors is just 1 minute.
The original Otis lifts in the North and South pillars in their turn proved inferior to the new (in 1899) French lifts and were scrapped from the south pillar in 1900 and from the north pillar in 1913 after failed attempts to re-power them with an electric motor. The north and south pillars were to remain without lifts until 1965 when increasing visitor numbers persuaded the operators to install a relatively standard and modern cable hoisted system in the north pillar using a cable-hauled counterbalance weight, but hoisted by a block and tackle system to reduce its travel to one third of the lift travel. The counterbalance is clearly visible within the structure of the North pillar. This latter lift was upgraded in 1995 with new cars and computer controls.
The South pillar acquired a completely new fairly standard electrically driven lift in 1983 to serve the Jules Verne restaurant. This was also supplied by Otis. A further 4 tonne service lift was added to the south pillar in 1989 by Otis to relieve the main lifts when moving relatively small loads or even just maintenance personnel.
The east and west hydraulic (water) lift works are on display and, at least in theory, are open to the public in a small museum located in base of the East and West tower, which is somewhat hidden from public view. Because the massive mechanism requires frequent lubrication and attention, public access is often restricted. However, when open, the wait times are much less than the other, more popular, attractions. The rope mechanism of the North tower is visible to visitors as they exit from the lift.

Second to the third level

The original spiral stairs to the third floor which were only 80 centimetres wide. Note also the small service lift in the background.

The original lift from the second to the third floor were also of a water powered hydraulic design supplied by Léon Edoux. Instead of using a separate counterbalance, the two lift cars counterbalanced each other. A pair of 81 metre long hydraulic rams were mounted on the second level reaching nearly half way up to the third level. A lift car was mounted on top of the rams. Ropes ran from the top of this car up to a sheave on the third level and back down to a second car. The result of this arrangement was that each car only travelled half the distance between the second and third levels and passengers were required to change lifts halfway walking between the cars along a narrow gangway with a very impressive and relatively unobstructed downward view. The 10 tonne cars held 65 passengers each or up to 4 tonnes.
One interesting feature of the original installation was that the hoisting rope ran through guides to retain it on windy days to prevent it flapping and becoming damaged. The guides were mechanically moved out of the way of the ascending car by the movement of the car itself. In spite of some antifreeze being added to the water that operated this system, it nevertheless had to close to the public from November to March each year.

The original Hydraulic pump for the Edoux lifts

View from the South-East edge on the second level.

The original lifts complete with their hydraulic mechanism were completely scrapped in 1982 after 97 years of service. They were replaced with two pairs of relatively standard rope hoisted cars which were able to operate all the year round. The cars operate in pairs with one providing the counterbalance for the other. Neither car can move unless both sets of doors are closed and both operators have given a start command. The commands from the cars to the hoisting mechanism are by radio obviating the necessity of a control cable. The replacement installation also has the advantage that the ascent can be made without changing cars and has reduced the ascent time from 8 minutes (including change) to 1 minute and 40 seconds. This installation also has guides for the hoisting ropes but they are electrically operated. The guide once it has moved out of the way as the car ascends automatically reverses when the car has passed to prevent the mechanism becoming snagged on the car on the downward journey in the event it has failed to completely clear the car. Unfortunately these lifts do not have the capacity to move as many people as the 3 public lower lifts and long queues to ascend to the third level are common. Most of the intermediate level structure present on the tower today was installed when the lifts were replaced and allows maintenance workers to take the lift half way.
The replacement of these lifts allowed the restructuring of the criss-cross beams in upper part of the tower and further allowed the installation of two emergency staircases. These replaced the dangerous winding stairs that were installed when the tower was constructed.

The entrance to Altitude 95.

Replica at the Paris Las Vegas Hotel, Nevada, United States

Replica at Walt Disney World's EPCOT

Replica at Tianducheng, Hangzhou, China.

Replica at Kings Island near Cincinnati, Ohio, United States

Replica of Eiffel Tower on factory building at Satteldorf near Crailsheim, Germany

Replica in Parizh village, Russia

The Eiffel Tower shape telecommunications tower in Da Lat, Vietnam

Restaurants

The tower has two restaurants: Altitude 95, on the first floor 311 ft (95 m) above sea level; and the Jules Verne, an expensive gastronomical restaurant on the second floor, with a private lift. This restaurant has one star in the Michelin Red Guide. In January 2007, the multi-Michelin star chef Alain Ducasse was brought in to run Jules Verne.^[35]

Great Pyramid of Giza

2010-05-18T08:09:00.000-07:00

The Great Pyramid of Giza (also called the
Pyramid of Khufu and the Pyramid of Cheops)
is the oldest and largest of the

The Great Pyramid of Giza (also called the Pyramid of Khufu and the Pyramid of Cheops) is the oldest and largest of the three pyramids in the Giza Necropolis bordering what is now El Giza, Egypt. It is the oldest of the Seven Wonders of the Ancient World, and the only one to remain largely intact. It is believed the pyramid was built as a tomb for fourth dynasty Egyptian Pharaoh Khufu (Cheops in Greek) and constructed over a 20-year period concluding around 2560 BC. The Great Pyramid was the tallest man-made structure in the world for over 3,800 years. Originally the Great Pyramid was covered by casing stones that formed a smooth outer surface; what is seen today is the underlying core structure. Some of the casing stones that once covered the structure can still be seen around the base. There have been varying scientific and alternative theories about the Great Pyramid's construction techniques. Most accepted construction hypotheses are based on the idea that it was built by moving huge stones from a quarry and dragging and lifting them into place.
There are three known chambers inside the Great Pyramid. The lowest chamber is cut into the bedrock upon which the pyramid was built and was unfinished. The so-called^[1] Queen's Chamber and King's Chamber are higher up within the pyramid structure. The Great Pyramid of Giza is the main part of a complex setting of buildings that included two mortuary temples in honor of Khufu (one close to the pyramid and one near the Nile), three smaller pyramids for Khufu's wives, an even smaller "satellite" pyramid, a raised causeway connecting the two temples, and small mastaba tombs surrounding the pyramid for nobles.

Building of the Great pyramid of Giza

It is believed the pyramid was built as a tomb for Fourth dynasty Egyptian pharaoh Khufu and constructed over a 14^[2] to 20 year period. Khufu's vizier, Hemon, or Hemiunu, is believed by some to be the architect of the Great Pyramid.^[3] It is thought that, at construction, the Great Pyramid was originally 280 Egyptian cubits tall, 146.478 metres (480.57 ft) but with erosion and absence of its pyramidion, its present height is 138.75 metres (455.22 ft). Each base side was 440 royal cubits, 230.37 metres (755.81 ft) in length. A royal cubit measures 0.524 metres.^[4] The mass of the pyramid is estimated at 5.9 million tonnes. The volume, including an internal hillock, is roughly 2,500,000 cubic meters.^[5] Based on these estimates, building this in 20 years would involve installing approximately 800 tonnes of stone every day. The first precision measurements of the pyramid were done by Egyptologist Sir Flinders Petrie in 1880–82 and published as The Pyramids and Temples of Gizeh.^[6] Almost all reports are based on his measurements. Many of the casing stones and inner chamber blocks of the Great Pyramid were fit together with extremely high precision. Based on measurements taken on the north eastern casing stones, the mean opening of the joints are only 0.5 millimeters wide (1/50th of an inch).^[7]

Great Pyramid of Giza from a 19th century stereopticon card photo

The pyramid remained the tallest man-made structure in the world for over 3,800 years,^[8] unsurpassed until the 160-meter-tall spire of Lincoln Cathedral was completed c. 1300. The accuracy of the pyramid's workmanship is such that the four sides of the base have an average error of only 58 millimeters in length ^[9] The base is horizontal and flat to within 21 mm^[10]. The sides of the square base are closely aligned to the four cardinal compass points (within 4 minutes of arc)^[11] based on true north, not magnetic north^[12], and the finished base was squared to a mean corner error of only 12 seconds of arc^[13]. The completed design dimensions, as suggested by Petrie's survey and subsequent studies, are estimated to have originally been 280 cubits in height by 440 cubits in length at each of the four sides of its base. These proportions equate to π/2 to an accuracy of better than 0.05% (corresponding to the approximation of π as 22/7). Some Egyptologists consider this to have been the result of deliberate design proportion^[14]. Verner wrote, "We can conclude that although the ancient Egyptians could not precisely define the value of π, in practice they used it".^[15] Petrie, author of Pyramids and Temples of Gizeh, who was the first accurate surveyor of Giza and the excavator and surveyor of the Pyramid of Meidum, concluded: "but these relations of areas and of circular ratio are so systematic that we should grant that they were in the builders design".^[16] Earlier in the chapter he wrote more specifically, that: “We conclude therefore that the approximation of 7 to 22 as the ratio of diameter to circumference was recognised”.^[17] These proportions equated to the four outer faces sloping by 51.843° or 51° 50′ 34″, which would have been understood and expressed by the Ancient Egyptians as a seked slope of 5½ palms^[18].

Materials

The Great Pyramid consists of an estimated 2.3 million limestone blocks with most believed to have been transported from nearby quarries. The Tura limestone used for the casing was quarried across the river. The largest granite stones in the pyramid, found in the "King's" chamber, weigh 25 to 80 tonnes and were transported more than 500 miles away from Aswan. Traditionally, ancient Egyptians cut stone blocks by hammering wooden wedges into the stone which were then soaked with water. As the water was absorbed, the wedges expanded, causing the rock to crack. Once they were cut, they were carried by boat either up or down the Nile River to the pyramid.^[19]

Casing stones

casing stone

At completion, the Great Pyramid was surfaced by white 'casing stones' – slant-faced, but flat-topped, blocks of highly polished white limestone. These were carefully cut to what is approximately a face slope with a seked of 5 1/2 palms to give the required dimensions. Visibly, all that remains is the underlying stepped core structure seen today. In AD 1300, a massive earthquake loosened many of the outer casing stones, which were then carted away by Bahri Sultan An-Nasir Nasir-ad-Din al-Hasan in 1356 to build mosques and fortresses in nearby Cairo. The stones can still be seen as parts of these structures to this day. Later explorers reported massive piles of rubble at the base of the pyramids left over from the continuing collapse of the casing stones, which were subsequently cleared away during continuing excavations of the site. Nevertheless, a few of the casing stones from the lowest course can be seen to this day in situ around the base of the Great Pyramid, and display the same workmanship and precision as has been reported for centuries. Petrie also found a different orientation in the core and in the casing measuring 193 centimeters ± 25 centimeters. He suggested a redetermination of north was made after the construction of the core, but a mistake was made, and the casing was built with a different orientation.^[20] Petrie related the precision of the casing stones as to being "equal to opticians' work of the present day, but on a scale of acres." and "to place such stones in exact contact would be careful work; but to do so with cement in the joints seems almost impossible."^[21]

Construction theories

Main article: Egyptian pyramid construction techniques

Many alternative, often contradictory, theories have been proposed regarding the Pyramid's construction techniques.^[22] Not all even agree that the blocks were quarried; Davidovits claims that they were cast in situ using a "limestone concrete", a theory which is rejected by other Egyptologists. The rest accept that it was built by moving huge stones from a quarry, being only unable to agree whether they were dragged, lifted or even rolled into place. The Greeks believed that slave labour was used, but modern Egyptologists accept that it was built by many tens of thousands of skilled workers. They camped near the pyramids and worked for a salary or as a form of paying taxes until the construction was completed.^{[citation needed]} Their cemeteries were discovered in 1990 by archaeologists Zahi Hawass and Mark Lehner. Verner posited that the labor was organized into a hierarchy, consisting of two gangs of 100,000 men, divided into five zaa or phyle of 20,000 men each, which may have been further divided according to the skills of the workers.^[23]
One mystery of the pyramid's construction is its planning. John Romer suggests that they used the same method that had been used for earlier and later constructions, laying out parts of the plan on the ground at a 1 to 1 scale. He writes that "such a working diagram would also serve to generate the architecture of the pyramid with precision unmatched by any other means." He devotes a chapter of his book to the physical evidence that there was such a plan.^[24] The 1925 Cole survey discovered as part of some planning an actual Original Builder's Mark, engraved into the pavement perpendicular to the N face.

Interior

Diagram of the interior structures of the Great Pyramid. The inner line indicates the pyramid's present profile, the outer line indicates the original profile.

The original entrance to the Great Pyramid is 17m (55’7”) vertically above ground level and 7.29m (23'11”) east of the center line of the pyramid. From this original entrance there is a Descending Passage 0.96m (3'2") in height and 1.04m (3'5") in width which goes down at an angle of 26° 31'23" through the masonry of the pyramid and then into the bedrock beneath it. After 105.23m (345’3”) the passage becomes level and continues for an additional 8.84m (29’) to the lower Chamber, which appears not to have been finished. There is a continuation of the horizontal passage in the south wall of the lower chamber; there is also a pit dug in the floor of the chamber. Some Egyptologists suggest this Lower Chamber was intended to be the original burial chamber, but that King Khufu later changed his mind and wanted it to be higher up in the pyramid.^[25]
28.2m (98’7”) from the entrance is a square hole in the roof of the Descending Passage. Originally concealed with a slab of stone, this is the beginning of the Ascending Passage. The Ascending Passage is 39.3m (129') long, as wide and high as the Descending Passage and slopes up at almost precisely the same angle. The lower end the Ascending Passage is closed by three huge blocks of granite, each about 1.5m (5') long. At the start of the Grand Gallery on the right-hand side there is a hole cut in the wall (and now blocked by chicken wire). This is the start of a vertical shaft which follows an irregular path through the masonry of the pyramid to join the Descending Passage. Also at the start of the Grand Gallery there is a Horizontal Passage leading to the "Queen's Chamber". The passage is 1.1m (3'8") high for most of its length, but near the chamber there is a step in the floor, after which the passage is 1.73m (5'8") high.
The Queen's Chamber is exactly half-way between the north and south faces of the pyramid and measures 5.75m (18'10") north to south, 5.23m (17'2") east to west and has a pointed roof with an apex 6.23m (20'5") above the floor. At the eastern end of the chamber there is a niche 4.67m (15'4") high. The original depth of the niche was 1.04m (3'5"), but has since been deepened by treasure hunters^{[citation needed]}.
In the north and south walls of the Queen's Chamber there are shafts, which unlike those in the King's Chamber that immediately slope upwards, are horizontal for around 2m (6') before sloping upwards. The horizontal distance was cut in 1872 by a British engineer, Waynman Dixon, who believed on the analogy of the King's Chamber that such shafts must exist. He was proved right, but because the shafts are not connected to the outer faces of the pyramid or the Queen's Chamber, their purpose is unknown. At the end of one of his shafts, Dixon discovered a ball of black diorite and a bronze implement of unknown purpose. Both objects are currently in the British Museum.^{[citation needed]}
The shafts in the Queen's Chamber were explored in 1992 by the German engineer Rudolf Gantenbrink using a crawler robot of his own design which he called "Upuaut 2". He discovered that one of the shafts was blocked by limestone "doors" with two eroded copper "handles". Some years later the National Geographic Society created a similar robot which drilled a small hole in the southern door, only to find another larger door behind it.^[26] The northern passage, which was difficult to navigate because of twists and turns, was also found to be blocked by a door.^[27]
The Grand Gallery continues the slope of the Ascending Passage, but is 8.6m (28') high and 46.68m (153') long. At the base it is 2.06m (6'9") wide, but after 2.29m (7'6") the blocks of stone in the walls are corbelled inwards by 7.6 cm (3") on each side. There are seven of these steps, so at the top the Grand Gallery is only 1.04m (3'5") wide. It is roofed by slabs of stone laid at a slightly steeper angle than the floor of the gallery, so that each stone fits into a slot cut in the top of the gallery like the teeth of a ratchet. The purpose was to have each block supported by the wall of the Gallery rather than resting on the block beneath it, which would have resulted in an unacceptable cumulative pressure at the lower end of the Gallery.^{[citation needed]}
At the upper end of the Gallery on the right-hand side there is a hole near the roof which opens into a short tunnel by which access can be gained to the lowest of the Relieving Chambers. The other Reliving Chambers were discovered in 1837/8 by Colonel Howard Vyse and J. S. Perring, who dug tunnels upwards using blasting powder.
The floor of the Grand Gallery consists of a shelf or step on either side, 51 cm (1'8") wide, leaving a lower ramp 1.04m (3'5") wide between them. In the shelves there are 54 slots, 27 on each side matched by vertical and horizontal slots in the walls of the Gallery. These form a cross shape that rises out of the slot in the shelf. The purpose of these slots is not known, but the central gutter in the floor of the Gallery, which is the same width as the Ascending Passage, has led to speculation that the blocking stones were stored in the Grand Gallery and the slots held wooden beams to restrain them from sliding down the passage^{[citation needed]}. This, in turn, has led to the proposal that originally many more than 3 blocking stones were intended, to completely fill the Ascending Passage^{[citation needed]}.
At the top of the Grand Gallery there is a step giving onto a horizontal passage approximately 1.02m (3'4") long, in which can be detected four slots, three of which were probably intended to hold granite portcullises. Fragments of granite found by Petrie in the Descending Passage may have come from these now vanished doors.
The King's Chamber is 10.47m (34'4") from east to west and 5.234m (17'2") north to south. It has a flat roof 5.974m (19'1") above the floor. 0.91m (3') above the floor there are two narrow shafts in the north and south walls (one is now filled by an extractor fan to try to circulate air in the pyramid). The purpose of these shafts is not clear: they appear to be aligned on stars or areas of the northern and southern skies, but on the other hand one of them follows a dog-leg course through the masonry so there was not intention to directly sight stars through them. They did not appear to contribute to air circulation, so the most likely explanation is a ritual one associated with the ascension of the king’s spirit^{[citation needed]}. The King's Chamber is entirely faced with granite, the blocks of stone being fitted with such precision that it is impossible to insert a piece of paper between them. Above the roof, which is formed of nine slabs of stone weighing in total about 400 tons, are five compartments known as Relieving Chambers. The first four, like the King's Chamber, have flat roofs formed by the floor of the chamber above, but the final chamber has a pointed roof. Vyse suspected the presence of upper chambers when he found that he could push a long reed through a crack in the ceiling of the first chamber. From lower to upper, the chambers are known as "Davidson Chamber", "Wellington Chamber", "Lady Arbuthnot's Chamber" and "Campbell's Chamber". It is believed that the compartments were intended to safeguard the King's Chamber from the possibility of a roof collapsing under the weight of stone above the Chamber. As the chambers were not intended to be seen, they were not finished in any way and a few of the stones still retain mason's marks painted on them. One of the stones in Campbell's Chamber bears a mark, apparently the name of a work gang, which incorporates the only reference in the pyramid to Pharaoh Khufu.
The only object in the King's Chamber is a rectangular granite "sarcophagus", one corner of which is broken. The sarcophagus is slightly larger than the Ascending Passage, which indicates that it must have been placed in the Chamber before the roof was put in place. Unlike the fine masonry of the walls of the Chamber, the sarcophagus is roughly finished, with saw marks visible in several places. This is in contrast with the finely finished and decorated sarcophagi found in other pyramids of the same period. Petrie suggested that such a sarcophagus was intended but was lost in the river on the way north from Aswan and a hurriedly made replacement was used instead. This ingenious theory does not explain why the sarcophagus could not have been finished in situ.^[28]

Entrance

Today tourists enter the Great Pyramid via the Robbers' Tunnel dug by workmen employed by Caliph al-Ma'mun around AD 820. The tunnel is cut straight through the masonry of the pyramid for approximately 27m (90'), then turns sharply left to encounter the blocking stones in the Ascending Passage. Unable to remove these stones, the workmen tunnelled up beside them through the softer limestone of the Pyramid until they reached the Ascending Passage. It is possible to enter the Descending Passage from this point, but access is usually forbidden.
In recent years entrance to the pyramid has been restricted to groups of 100 morning and afternoon. As tickets are highly prized, those wishing to enter must queue outside the right ticket office for an hour or more before it opens. Under Zahi Hawass, photography inside the pyramid is now strictly forbidden.

King's Chamber and the Golden Mean

At the end of the lengthy series of entrance ways leading into the interior is the structure's main chamber, the King's Chamber. This granite room was originally 10 × 20 × 11.4 cubits, or about 5.235 m × 10.47 m × 5.974 m,^[29]^[30] comprising a double 10 × 10 cubit square floor, and a height equal to half the double square's diagonal. Some believed that the height was consistent with the geometric methods for determining the Golden Ratio φ (phi) as the height is approximately phi times the width minus ½, while phi can be derived from other dimensions of the pyramid,^[31] but evidence from Petrie’s surveys and later conclusions drawn by others shows that the circular proportions were deliberately incorporated into the internal and external designs of the Great Pyramid by its architects and builders for symbolic reasons.^[32] The so called golden ratio phi simply exists in the proportions of the architecture as an inadvertent by-product of the inclusion of the circular proportions. The reason for the inadvertent inclusion is that phi, the golden ratio, has a naturally occurring mathematical relation to the circular ratio pi that is unrelated to the architecture or geometry, and which was unknown to the pyramid's builders. Petrie confirmed that the King’s Chamber was a triumph of Egyptian geometry, the ratio of its length to the circuit of the side wall being the same as the ratio of 1 to pi, and that the exterior of the pyramid had been built to the same proportions.^[32]^[33]^[34]

Pyramid complex

Map of Giza pyramid complex

Main article: Giza pyramid complex

The Great Pyramid is surrounded by the usual complex of buildings. The Pyramid Temple, which stood on the east side of the pyramid and measured 52.2m (171') north to south and 40m (132') east to west, has almost entirely disappeared apart from the black basalt paving. There are only a few remnants of the causeway which linked the pyramid with the valley and the presumed Valley Temple which, if it exists, is buried beneath the village of Kafr es-Samman.
On the south side are the subsidiary pyramids, popularly known as Queens' Pyramids. Three remain standing to nearly full height but the fourth was so ruined that its existence was not suspected until the recent discovery of the first course of stones and the remains of the capstone. Herodotus claims that Khufu was a tyrant who prostituted his daughter to raise money to build the Great Pyramid. She, however, requested a stone from each customer and used them to build her smaller pyramid. There is no evidence to support this tale (though it may reflect an arranged marriage advantageous for Khufu) and the Queens' Pyramids may not have housed members of the court. Some have suggested that they corresponded to the later canopic jars for burial of the royal viscera - heart, lungs, liver and entrails.
Hidden beneath the paving around the pyramid was the tomb of Queen Hetepheres, sister-wife of Sneferu and mother of Khufu. Discovered by accident by the Reisner expedition, the burial was intact, though the carefully sealed coffin proved to be empty. Reisner suggests that Hetepheres was originally buried near her husband's pyramid but the tomb was robbed and the mummy destroyed. Khufu transferred the burial to his own pyramid complex, but the priests responsible for the burial did not dare tell him that his mother's body was missing.
There are three boat-shaped pits around the pyramid, of a size and shape to have held complete boats, though so shallow that any superstructure must have been removed or disassembled. It is not clear how these pits were sealed, as the span is too large for stone slabs, which may be why they were found empty apart from ropes and a few fragments of gilded wood found in one pit by Reisner. However in May, 1954, the Egyptian archaeologist Kamal el-Mallakh discovered a fourth pit, a long, narrow rectangle, still covered with slabs of stone weighing up to 15 tons. Inside were 1224 pieces of wood, the longest 23m (75') in length, the shortest 10 cm (4"). These were entrusted to a native boat builder, Haj Ahmed Yusuf, who slowly and methodically worked out how the pieces fit together. The entire process, including conservation and straightening of the warped wood, took fourteen years.
The result is a spectacular cedar-wood boat 43.6m (143') long, its timbers held together by ropes. It is not clear how the boat was made water-tight. Early theories that soaking in water caused the wood to swell and thus become water-tight did not prove effective with the modern reconstruction "Horizon of Min" based on boats found in the Wadi Gawasis excavation and the reconstructers had recourse to traditional fibre caulking reinforced by beeswax. There is no sign of such measures on the Khufu boat, which may simply mean that the boat was never floated. The name "Djedefre", Khufu's son and successor, is found on some of the slabs of stone that sealed the pit, indicating that the boat was put there by Khufu's son.
The reconstructed boat is housed in a special boat-shaped, air-conditioned museum beside the pyramid. During construction of this museum, which stands above the boat pit, a second sealed boat pit was discovered. It was deliberately left unopened in the hope that future excavation techniques will allow more information to be recovered, however a hole was drilled in the sealing stones and air extracted from the pit in the hope of obtaining information about the ancient atmosphere. However as the air was found to be identical to modern air it was concluded that the pit is not hermetically sealed.
The Gizeh pyramid complex, which includes the pyramids of Khufu, Khafre and Menkaure, is surrounded by a cyclopaean stone wall, outside which Mark Lehner has discovered the town where the workers on the pyramids were housed. Among the discoveries are communal sleeping quarters, bakeries, breweries and kitchens (with evidence showing that bread and fish were staples of the diet), a hospital and a cemetery (where some of the skeletons were found with signs of trauma associated with accidents on a building site).^[28]

Thieves, tourists and excavators

Although succeeding pyramids were smaller, pyramid building continued until the end of the Middle Kingdom. However, as authors Briar and Hobbs claim, "all the pyramids were robbed" by the New Kingdom, when the construction of royal tombs in a desert valley, now known as the Valley of the Kings, began.^[35]^[36] Joyce Tyldesley states that the Great Pyramid itself "is known to have been opened and emptied by the Middle Kingdom", before the Arab caliph Abdullah al-Mamun entered the pyramid around AD 820.^[37]

Pandara vanniyan

2010-05-18T07:36:00.000-07:00

Name- Pandara Vanniyan

Pandara Vanniyan or Pandara Vannian was a rebel Tamil chief from the Vanni region who was known as one of last native chiefs to challenge British rule in the Island nation of Sri Lanka. His grandson is Pannirukaran Mylvaganam.

Biography

Kulasegaram Vairamuthu Pandaravanniyan was the last king of Vanni. Some of the history books say that he had a sister and two brothers but the truth is he only had 2 younger brothers called "Kaylaa vanniyan" and "Periya Meynaar". Kumarasinghe Mahavanniya’s family of Nuwarawewa was related by marriage to Pandara Vanniyan.

Conflict with the Colonial rule

With the capture of the Jaffna kingdom by the Portuguese in 1621, the Vanni was under their nominal control and 'Parangichetticulam' of the Vanni may have been the fort of the Portuguese.[1]

With the arrival of the Dutch colonials on the scene they were only able to exact yearly tribute of 42 elephants. About the year 1782 the continued conflicts came to an end when the Dutch once and for all defeated the Vanniyars. Every foreign power found the Vanniyars a formidable foe and this could be explained in the words of Lewi, It is characteristic of the spirit of this people that the Dutch met nowhere a more determined resistance than from one of the native princesses, the Vannichi Maria Sembatte, whom they were obliged to carry away as prisoner, and to detain in captivity in the fort of Colombo'.(MVD,p 17 & 18 ).[2]

The Vanniyars, thence commenced to live a wild and marauding life and carried on a predatory warfare against the Dutch in Mannar and Trincomalee and even penetrated to the Jaffna peninsula. The Dutch had to build forts along the river to keep them at bay. With the advent of the British Pandara Vanniyan started a revolt to expel them from his district with the assistance of the Kandyans kingdom. He attacked the government house in Mullaiteevu and drove out the garrison which was under the command of one Captain Drieberg and seized the fort.[3]

The end

The victory of the Vanniyars was short lived. Three detachments from Jaffna , Mannar and Trincomalee were dispatched and the Vanniyars were defeated in the Mannar district. Although Pandara Vanniyan was active again his grandiose scheme to rule the Vanni faded away after 1811. The tomstone of Pandaara vanniyar defeat is still in Vanni.[4]

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