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Ardashir II ... Argead Dynasty
Ardashir II
king of the Sasanian empire in ancient Persia (reigned AD 379-383). During the reign of his brother Shapur II, he had been king of Adiabene (now a region of northeast Iraq), where he took part in the persecution of Christians. After Shapur's death, he was set on the throne by ...
Ardea
ancient town of the Rutuli people and now a modern village in the Lazio regione, west-central Italy. It lies 23 miles (37 km) south of Rome. In ancient times it was an important centre of the cult of Juno. Ardea developed into one of the most important Latin cities and ...
Arden, Elizabeth
Canadian-born American businesswoman who developed a successful line of cosmetics and a chain of beauty salons and spas.
Arden, Enoch
fictional character, protagonist of Alfred, Lord Tennyson's narrative poem Enoch Arden (1864).
Arden, Eve
American actress best known for her role as the title character of Our Miss Brooks on radio (1948-56) and television (1952-56).
Arden, John
one of the most important of the British playwrights to emerge in the mid-20th century. His plays mix poetry and songs with colloquial speech in a boldly theatrical manner and involve strong conflicts purposely left unresolved.
Ardennes
wooded plateau covering part of the ancient Forest of Ardennes, occupying most of the Belgian provinces of Luxembourg, Namur, and Liege; part of the Grand Duchy of Luxembourg; and the French departement of Ardennes. It is an old plateau comprising the western extension of the Middle Rhine Highlands, stretching in ...
Ardhanarishvara
composite male-female figure of the Hindu god Shiva, together with his consort Parvati. As seen in many Indian and Southeast Asian sculptures, the right (male) half of the figure is adorned with the traditional ornaments of Shiva. Half of the hair is piled in a hairdress of matted locks; half ...
Ardi
nickname for a partially complete, female hominin skeleton found by Ethiopian paleontologist Yohannes Haile-Selassie at Aramis, in the Afar depression of Ethiopia's middle Awash River valley, in 1994. Ardi has been dated to 4.4 million years old, and she is one of more than 100 specimens belonging to Ardipithecus ramidus, ...
Ardipithecus: A Hominin Ancestor for Lucy?: Year in Review 2010
The long-awaited results of a monumental effort to reconstruct the skeletal biology, paleoecology, and evolutionary position of Ardipithecus ramidus were published at last in the Oct. 2, 2009, issue of the journal Science. The issue featured 11 research articles written by an international team of 47 authors and a number ...
Ardmore
city, seat (1907) of Carter county, southern Oklahoma, U.S., north of the Red River, near Lake Texoma and the Texas state line. Founded in 1887 in Chickasaw Indian Territory after the arrival of the Atchison, Topeka and Santa Fe Railroad, the town was named for the Philadelphia suburb that was ...
Ardon, Mordecai
eminent Israeli painter who combined jewel-like, brilliantly coloured forms with virtuoso brushwork. He created modern, semiabstract paintings that are deeply moving.
Ards
district, eastern Northern Ireland. Formerly within County Down, Ards was established as a district in 1973. It extends northward from just south of the village of Killinchy along the western shoreline of Strangford Lough (inlet of the sea) to the town of Newtownards and encompasses the peninsula of land east ...
Arduino, Giovanni
the father of Italian geology, who established bases for stratigraphic chronology by classifying the four main layers of the Earth's crust as Primary, Secondary, Tertiary, and Quaternary.
are
basic unit of area in the metric system, equal to 100 square metres and the equivalent of 0.0247 acre. Its multiple, the hectare (equal to 100 ares), is the principal unit of land measurement for most of the world.
Areas and Volumes of the Great Lakes
The combined area of the Great Lakes (some 94,250 square miles [244,106 square km]) represents the largest surface of fresh water in the world. The lakes-Superior, Michigan, Huron, Erie, and Ontario-are located in east-central North America and provide a natural border between Canada and the United States.
Arecales
order of flowering plants that contains only one family, Arecaceae (also known as Palmae), which comprises the palms. Nearly 2,400 species in 189 genera are known. The order includes some of the most important plants in terms of economic value.
Arecibo
town, northern Puerto Rico. It lies on a small inlet near the mouth of the Arecibo River. One of the oldest municipalities in the commonwealth, it was authorized in 1537 by the Spanish crown and settled in 1556. In 1616 it was chartered as a town and in 1778 received ...
Arecibo Observatory
astronomical observatory located 16 km (10 miles) south of the town of Arecibo in Puerto Rico; it is the site of the world's largest single-unit radio telescope. This instrument, built in the early 1960s, employs a 305-metre (1,000-foot) spherical reflector consisting of perforated aluminum panels that focus incoming radio waves ...
Arecibo River
river in west-central Puerto Rico. The Arecibo River rises in the Cordillera Central just east of Mount Guilarte. It flows north-northeast about 40 miles (65 km) through a coffee-growing region and descends across the northern coastal plain to empty into the Atlantic Ocean just east of the port of Arecibo. ...
arena
central area of an amphitheatre (q.v.).
Arena Chapel
(consecrated March 25, 1305) small chapel built in the first years of the 14th century in Padua, Italy, by Enrico Scrovegni and containing frescoes by the Florentine painter Giotto (see ). A "Last Judgment" covers the entire west wall. The rest of the chapel is covered with frescoes in three ...
Arenas, Reinaldo
Cuban-born writer of extraordinary and unconventional novels who fled persecution and immigrated to the United States.
arenavirus
any virus belonging to the family Arenaviridae. The name of the family is derived from the Latin arenosus, meaning "sandy," which describes the grainy appearance of arenavirus ribosomes (protein-synthesizing particles). Arenaviruses have spherical, enveloped virions (virus particles) that are 110-130 nm (1 nm = 109 metre) in diameter. The nucleocapsid, ...
Arend-Roland, Comet
long-period comet remarkable for its anomalous second tail, which projected toward rather than away from the Sun. It was one of the brightest naked-eye comets of the 20th century. It was discovered photographically on the night of November 8-9, 1956, by Sylvain Arend and Georges Roland at the Royal Observatory, ...
Arendal
town and port, southern Norway. Its excellent harbour is on Tromoy Sound, a protected sound sheltered by the offshore island of Tromoy. A port since the 14th century, Arendal had the largest fleet in Norway before the steamship era. From the 16th century it prospered from timber exports. Some timber ...
Arendt, Hannah
German-born American political scientist and philosopher known for her critical writing on Jewish affairs and her study of totalitarianism.
arenite
any sedimentary rock that consists of sand-sized particles (0.06-2 millimetres [0.0024-0.08 inch] in diameter), irrespective of composition. More formal nomenclature of such rocks is based on composition, particle size, and mode of origin-e.g., sandstone, quartzite, lithic arenite, and feldspathic arenite.
Arenosol
one of the 30 soil groups in the classification system of the Food and Agriculture Organization (FAO). Arenosols are sandy-textured soils that lack any significant soil profile development. They exhibit only a partially formed surface horizon (uppermost layer) that is low in humus, and they are bereft of subsurface clay ...
Arensky, Anton
Russian composer known especially for his chamber music and songs.
Areopagitica
pamphlet by John Milton, published in 1644 to protest an order issued by Parliament the previous year requiring government approval and licensing of all published books. Four earlier pamphlets by the author concerning divorce had met with official disfavour and suppressive measures.
Areopagus
earliest aristocratic council of ancient Athens. The name was taken from the Areopagus ("Ares' Hill"), a low hill northwest of the Acropolis, which was its meeting place.
Arequipa
city, southern Peru, in the Chili River valley of the Andes Mountains. Arequipa lies at more than 7,550 feet (2,300 metres) above sea level, at the foot of the dormant cone of Misti Volcano, which reaches an elevation of 19,098 feet (5,821 metres). Flanking Misti are Mounts Chachani and Pichupichu. ...
Ares
in Greek religion, god of war or, more properly, the spirit of battle. Unlike his Roman counterpart, Mars (q.v.), he was never very popular, and his worship was not extensive in Greece. He represented the distasteful aspects of brutal warfare and slaughter. From at least the time of Homer, who ...
Ares
family of two launch vehicles, Ares I and Ares V, for the proposed Constellation program, the manned U.S. spaceflight program that was scheduled to succeed the space shuttle program and focus on missions to the Moon and Mars. In June 2006 the National Aeronautics and Space Administration (NASA) named the ...
Aretaeus Of Cappadocia
Greek physician from Cappadocia who practiced in Rome and Alexandria, led a revival of Hippocrates' teachings, and is thought to have ranked second only to the father of medicine himself in the application of keen observation and ethics to the art. In principle he adhered to the pneumatic school of ...
arete
(French: "ridge"), in geology, a sharp-crested serrate ridge separating the heads of opposing valleys (cirques) that formerly were occupied by Alpine glaciers. It has steep sides formed by the collapse of unsupported rock, undercut by continual freezing and thawing (glacial sapping; see cirque). Two opposing glaciers meeting at an arete ...
Arethusa
in Greek mythology, a nymph who gave her name to a spring in Elis and to another on the island of Ortygia, near Syracuse.
Aretino, Pietro
Italian poet, prose writer, and dramatist celebrated throughout Europe in his time for his bold and insolent literary attacks on the powerful. His fiery letters and dialogues are of great biographical and topical interest.
Arevaci
a Celtiberian tribe, thought by Classical writers to have formed from the mingling of pre-Roman Iberians and Celts, who inhabited an area near Numantia and Uxama in what is now Spain. The Celtiberians excelled at horsemanship, fighting, and metalworking. They wore sewn garments made of woven and dyed cloth.
Arevalo (Bermejo), Juan Jose
president of Guatemala (1945-51), who pursued a nationalistic foreign policy while internally encouraging the labour movement and instituting far-reaching social reforms.
Arevalo Martinez, Rafael
novelist, short-story writer, poet, diplomat, and director of Guatemala's national library for more than 20 years. Though Arevalo Martinez's fame has waned, he is still considered important because of his short stories, one in particular.
Arezzo
city, Toscana (Tuscany) regione, north-central Italy, in a fertile plain near the confluence of the Chiana and Arno rivers southeast of Florence. An important Etruscan city, it was known to the Romans as Arretium and was noted for its red-clay Arretine pottery. A flourishing commune in the Middle Ages, it ...
Arfersiorfik Fjord
fjord in western Greenland, extending east from Davis Strait to the inland icecap. It is 95 miles (152 km) long with a maximum width of 15 miles (24 km). Its arms receive several glaciers, including the Nordenskiolds. Niaqornaarsuk, a settlement on the northern shore near the fjord's mouth, was the ...
Arfons, Art
American automotive racer, three-time holder of the world's land-speed record for wheeled vehicles.
arfvedsonite
amphibole mineral, an iron-rich sodium silicate. Lithium and magnesium replace iron in the structure to form eckermannite. Both minerals characteristically occur as dark-green crystals in alkali igneous rocks and their associated pegmatites. For chemical formula and detailed physical properties, see amphibole (table).
argali
the largest living wild sheep, native to the highlands of Central Asia. Argali is a Mongolian word for "ram." There are eight subspecies of argali. Mature rams of large-bodied subspecies stand 125 cm (49 inches) high at the shoulder and weigh more than 140 kg (300 pounds). Rams in small-bodied ...
Argall, Sir Samuel
English sailor and adventurer who defended British colonists in North America against the French.
Argand burner
first scientifically constructed oil lamp, patented in 1784 in England by a Swiss, Aime Argand. The first basic change in lamps in thousands of years, it applied a principle that was later adapted to gas burners. The Argand burner consisted of a cylindrical wick housed between two concentric metal tubes. ...
Argand diagram
graphic portrayal of complex numbers, those of the form x+yI, in which x and y are real numbers and I is the square root of 1. It was devised by the Swiss mathematician Jean Robert Argand about 1806. A similar representation had been proposed by the Danish surveyor Caspar Wessel ...
Argead Dynasty
ruling house of ancient Macedonia from about 700 to about 311 BC; under their leadership the Macedonian kingdom was created and gradually gained predominance throughout Greece. From about 700 the founder of the dynasty, Perdiccas I, led the people who called themselves Macedonians eastward from their home on the Haliacmon ...