Orinoco X.or-e-'no-koX River Major river, South America. It rises on the western slopes of the Parima Mountains along the border between Venezu¬ ela and Brazil. It flows in a giant arc through Venezuela for about 1,700 mi (2,740 km) and enters the Atlantic Ocean near the island of Trinidad. It forms part of the border between Colombia and Venezuela. With its tribu¬ taries, it is the northernmost of South America’s four major river systems. The aquatic fauna include the piranhas and the Orinoco crocodile. The river basin is largely inhabited by indigenous Indian groups.
oriole Any songbird of 24 species in the Old World genus Oriolus (fam¬ ily Oriolidae) or 30 species in the New World genus Icterus (family Ict- eridae). Males typically are black and yellow or black and orange, with some white. Females are less colourful. Orioles are not easily seen but may be detected by their loud whistling and jarring notes. All are insect eaters (several species also eat fruit) in woodlands and gardens, chiefly in warm regions. The only European species is the 9.5-in. (24-cm) golden oriole ( O . oriolus). Other Oriolus species are found in Africa, Asia, and Australia. The Baltimore oriole (/. galbula) breeds in North America east of the Rocky Mountains. See photograph above.
Orion Xo-'ri-onX In Greek mythology, a powerful hunter. He was some¬ times said to be the son of Poseidon. He drove the wild beasts out of the island of Chios and fell in love with Merope, daughter of the island’s king. Disapproving of Orion, the king had him blinded, but his vision was restored by the rays of the rising sun. He later went to Crete to live and hunt with Artemis. Some legends hold that he was killed by Artemis or Apollo out of jealousy; another tells that he was fatally bitten by a scor¬ pion. After his death the gods placed him in the sky as a constellation.
Orion Xo-'rl-onX Nebula Bright nebula, faintly visible to the unaided eye in the sword of the hunter’s figure in the constellation Orion. About 1,500 light-years from Earth, it contains hundreds of very hot young stars clustered about a group of four massive stars known as the Trapezium. Radiation primarily from these four stars excites the nebula to glow. Dis¬ covered in the early 17th century, it was the first nebula to be photo¬ graphed (1880).
Orissa State (pop., 2001 prelim: 36,706,920), eastern India. It lies on the Bay of Bengal and is bordered by Andhra Pradesh, Chhattisgarh, Jhark¬ hand, and West Bengal states. It occupies an area of 60,119 sq mi (155,707 sq km), and its capital is Bhubaneshwar; Cuttack is the largest city. Part of the ancient kingdom of Kalinga, it was a stronghold of Hinduism before its conquest by the Afghan rulers of Bengal in 1568, when it became part of the Mughal Empire. It was ruled by Britain from 1803 until India’s independence in 1947 and became a state in 1950. Situated in a tropical savanna that is subject to cyclones, it has a largely rural population, which is engaged mainly in agriculture. Crops include rice, oilseed, jute, and sugarcane. It has a rich artistic heritage and contains some of the best examples of Indian art and architecture.
Orizaba See Citlaltepetl Orkhon River See Orhon River
Orkney Islands Island group (pop., 2001: 19,245), Scotland. Lying north of the Scottish mainland, it comprises more than 70 islands and islets and constitutes the Orkney council area. The Orkney Islands, only 20 of which are inhabited, were the Orcades of ancient Classical literature. There is much evidence of prehistoric inhabitants. Norse raiders arrived in the late 8th century ad and colonized the islands in the 9th century. Thereafter they were ruled by Norway and Denmark until Scotland annexed them in 1472. It is a prosperous agricultural area. Kirkwall is the administrative seat.
Orlando City (pop., 2000: 185,951), central Florida, U.S. Settlement began c. 1844 around an army post. It was renamed in 1857 to honour Orlando Reeves, an army sentry killed during the Seminole Wars. After 1950 the development of the aerospace complex at Cape Canaveral and, after 1971, of nearby Disney World boosted the city’s population and economy. It is also the centre of a citrus farming region.
Orlando, Vittorio Emanuele (b. May 19, 1860, Palermo, Italy—d. Dec. 1, 1952, Rome) Italian politician and prime minister (1917-19). He was elected to Italy’s Chamber of Deputies in 1897 and served in cabi¬ net positions from 1903. As prime minister, he led Italy’s delegation to the Paris Peace Conference, but he was unable to obtain concessions from the Allies for Italian-claimed territory and resigned. As president of the Chamber of Deputies (1919-25), he resigned in protest against the elec¬ toral fraud of Benito Mussolini’s Fascist Party. He was president of the postwar Constituent Assembly (1946^-7).
Orleans \or-la-'a n \ ancient Aurelianum City (pop., 1999: 113,126), capital of the Centre region , north-central France. It was conquered by Julius Caesar in 52 bc and became an intellectual centre under Charle¬ magne. It was a major cultural centre in the Middle Ages and became a royal duchy under Philip VI in 1344. During the Hundred Years' War, the English siege in 1429 was relieved by Joan of Arc, known as the Maid of Orleans, and her troops. Located on the Loire River in a fertile valley, it is important for market gardening, horticulture, and textile production.
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1418 I Orleans ► Oromo
Orleans, house of Name of the cadet or junior branch of the Valois and Bourbon houses of France. Of the four dynasties of princes, Philippe I (1336-75) died without an hem Descendants of the second dynasty, headed by Louis I (1372-1407), held the title until 1545. The third dynasty was headed by Gaston (1608-60), whose title from 1626 passed to the fourth dynasty under Philippe I (1640-1701), younger brother of Louis XIV. Philippe’s descendants included Louis-Philippe-Joseph, duke d' Orleans, and Louis-Philippe, king of France from 1830 to 1848.
Orleans, Louis-Philippe-Joseph, duke d' known as Philippe Egalite (b. April 13, 1747, Saint-Cloud, France—d. Nov. 6, 1793, Paris) French Bourbon prince who supported popular democracy in the French Revolution. A cousin of Louis XVI, he disapproved of Marie-Antoinette and lived away from the royal court at Versailles. In 1787 he was exiled to his estates for challenging the king’s authority. In 1789 he was elected to the Estates General and soon joined the Third Estate. After joining the Jacobin Club (1791), he renounced his title of nobility (1792) and accepted the name Philippe Egalite from the Paris Commune. In the National Con¬ vention, he supported the radicals, but, after his son Louis-Philippe defected to the Austrians, he was accused of conspiracy, arrested, and guillotined.
Orlov Vsr-'loA, Aleksey (Grigoryevich), Count (b. Oct. 5, 1737, Lyutkino, Tver province, Russia—d. Jan. 5, 1808, Moscow) Russian mili¬ tary officer. He became an officer in the Russian guards and adviser to his brother Count Grigory G. Orlov, with whom he planned the overthrow of Peter III (1762) and the installation of Catherine II as empress. Promoted to major general, he was given command of the Russian fleet in the Russo-Turkish War.
Orlov, Grigory (Grigoryevich), Count (b. Oct. 17, 1734, Lyut¬ kino, Tver Province, Russia—d. April 24, 1783, Neskuchnoye, near Mos¬ cow) Russian military officer and lover of Catherine II. An artillery officer, he fought in the Seven Years' War. While stationed in St. Petersburg, he met the grand duke Peter (later Peter III) and his wife, Catherine, whose lover Orlov became c. 1760. After Peter ascended the throne (1762), Orlov and his brother, Count Aleksey Orlov, planned the coup d'etat that over¬ threw Peter and made Catherine empress of Russia. As Catherine’s close adviser, he proposed agrarian reforms to help the serfs, but little was accomplished. He lost favour at court c. 1772.
Ormandy, Eugene orig. Jeno Ormandy Blau (b. Nov. 18, 1899, Budapest, Austria-Hungary—d. March 12, 1985, Philadelphia, Pa., U.S.) Hungarian-born U.S. conductor. A violin prodigy, he became professor of violin at the Budapest Royal Academy at age 17. In 1921 he went to New York City, where he played in and conducted a theatre orchestra; he gained national prominence as conductor of the Minneapolis Symphony Orches¬ tra (1931-36). He shared conductorship of the Philadelphia Orchestra with Leopold Stokowski for two years before becoming sole conductor in 1938, and he led the orchestra until he was made laureate in 1980. Ormandy shaped the orchestra’s sound by developing the lush, velvety string colour that became its trademark, and the orchestra made scores of recordings under him.