applique See quilting
Appomattox \,a-p3-'ma-t3ks\ Court House Former town, southern central Virginia, U.S., site of the surrender of Robert E. Lee to Ulysses S. Grant on April 9, 1865, effectively ending the American Civil War. It was virtually deserted after the removal of the county seat to the new town of Appomattox in 1892. It became a national historical monument in 1940 and a national historical park in 1954.
apprenticeship Training in an art, trade, or craft under a legal agree¬ ment defining the relationship between master and learner and the dura¬ tion and conditions of their relationship. Known from antiquity, apprenticeship became prominent in medieval Europe with the emergence of the craft guilds. The standard apprenticeship lasted seven years. Dur¬ ing the Industrial Revolution a new kind of apprenticeship developed in which the employer was the factory owner and the apprentice, after a period of training, became a factory worker. The increasing need for semiskilled workers led to the development of vocational and technical schools in Europe and the U.S., especially after World War II. Some industries in the U.S., such as construction, continue to employ workers in an apprenticeship arrangement.
approximation, linear See linear approximation
APRA Va-pra\ in full Alianza Popular Revolucionaria Ameri¬ cana Party founded by Victor Raul Haya de ia Torre (1924), which domi¬ nated Peruvian politics for decades. Largely synonymous with the so-called Aprista movement, it was dedicated to Latin American unity, the nationalization of foreign-owned enterprises, and an end to the exploi¬ tation of Indians. Supported by workers and middle-class liberals, the party wielded significant power, but conservative forces took extraordi¬ nary measures to prevent Haya de la Torre from ever gaining the presi¬ dency. An APRA candidate, Alan Garcia, finally became president in 1985. See also indigenismo.
apraxia \a-'prak-se-o\ Disturbance in carrying out skilled acts, caused by a lesion in the cerebral cortex; motor power and mental capacity remain intact. Motor apraxia is the inability to perform fine motor acts. Ideational apraxia is loss of the ability to plan even a simple action. In ideokinetic apraxia, there is no coordination between formation of ideas and motor activity; affected persons can do certain things automatically but not delib¬ erately. Constructional apraxia is the inability to put together elements to form a meaningful whole.
apricot Fruit of the tree Prunus armeniaca, in the rose family, culti¬ vated generally throughout the temperate regions of the world and used fresh, cooked in pastries, or preserved by canning or drying. Apricot trees are large and spreading, with heart-shaped, dark green leaves. Flowers are white. The fruit is nearly smooth and generally similar to the peach in shape but with little to no hairiness when ripe. Apricots are a good source of vitamin A and are high in natural sugars. Dried apricots are an excel¬ lent source of iron.
April Fools' Day or All Fools' Day First day of April, named for the custom of playing practical jokes on that date. Though it has been observed for centuries in several countries, including France and Britain, its origin is unknown. It resembles the Hilaria festival of ancient Rome (March 25) and the Hou festival of India (ending March 31). The custom of playing April Fools’ jokes was brought to America by the British.
April Theses Program developed by Vladimir Ilich Lenin during the Rus¬ sian Revolution of 1917, calling for Soviet control of state power. In the theses, published in April 1917, Lenin advocated seizing power from the Provisional Government, withdrawing from World War I, and distribut¬ ing land among the peasantry. The theses contributed to the July Days uprising and the Bolshevik coup d’etat in October.
apse Semicircular or polygonal termination to the choir, chancel (see cathedral), or aisle of a public build¬ ing, first used in pre-Christian Roman architecture. Originally a large niche to hold the statue of a deity in a temple, the apse also appeared in ancient baths and basili¬ cas. The domed apse became a stan¬ dard part of the Christian church plan.
Apuleius \,a-p3-la-3s\, Lucius (b.
c. ad 124, Madauros, Numidia—d. after 170?) Roman Platonic philoso¬ pher, rhetorician, and author. His The Golden Ass, a prose narrative of the ribald adventures of a young man who is changed into an ass, was long influential. This novel, considered a revelation of ancient manners, is valuable for its description of the ancient religious mysteries.
Apuleius’s philosophical treatises include three books on Piato, two of which survive.
Apulia See Puglia
Apure \a-'pii-ra\ River River, western Venezuela. The major navi¬ gable tributary of the Orinoco River, the Apure rises in the Cordillera de Merida and flows about 510 mi (820 km) northeast and east through the heart of Venezuela’s Llanos (plains), the country’s principal cattle-raising area.
Apurimac \,a-pur- , e-,mak\ River River, southern Peru. Arising in the Andes Mountains in Peru, it is the most distant source of the Amazon River. It flows northwest to join the Urubamba River and form the Ucayali River. For most of its 430-mi (700-km) length, it flows through narrow canyons, and its course is interrupted by falls and rapids. Short stretches of its lower course are also called the Ene River and the Tambo River.
Aqa Khan See Aga Khan
Aqaba Va-ko-boV Gulf of Northeastern arm of the Red Sea, between Saudi Arabia and the Sinai Peninsula. It varies in width from 12 to 17 miles (19 to 27 km) and is 100 miles (160 km) long. Its head touches Egypt, Israel, Jordan, and Saudi Arabia. Its only sheltered harbour is Dhahab (Dahab), Egypt; Jordan and Israel created the ports of Al-'Aqabah and Elat, respectively, as outlets to the Red Sea and the Indian Ocean.
Aqhat Epic Va-kat\ Ancient West Semitic legend explaining the earth’s barrenness during the dry summer months, known only in fragmentary form from three tablets excavated in northern Syria and dating to about the 14th century bc. It records the birth of a prince, Aqhat, in response to prayers. As a youth, Aqhat comes into possession of a bow intended for the goddess Anath and is killed by her when he refuses to part with it. His death brings famine, and his father and sister set out to avenge him, but there the text ends.
Aqmola See Astana
aquaculture or fish farming or mariculture Vmar-s-.kol-choA Rearing of fish, shellfish, and some aquatic plants to supplement the natu¬ ral supply. Fish are reared in controlled conditions worldwide. Though most aquaculture supplies the commercial food market, many govern¬ mental agencies engage in it to stock lakes and rivers for sport fishing. It also supplies goldfish and other decorative fish for home aquariums and bait fish for sport and commercial fishing. Carp, trout, catfish, tilapia, scal¬ lops, mussels, lobsters, and oysters are well-known species raised through aquaculture.
Apse, basilica of S. Vitale, Ravenna,
526-547
AUNARI—ART RESOURCE
© 2006 Encyclopaedia Britannica, Inc.
92 I aquamarine ► Arab-lsraeli wars
aquamarine Pale greenish blue or bluish green variety of beryl that is valued as a gemstone. The most common variety of gem beryl, it occurs in pegmatites, in which it forms much larger and clearer crystals than emer¬ ald, the dark green variety of beryl. Aquamarine occurs in Brazil, which is the chief source, and in such other sites as the Ural Mountains, Mada¬ gascar, Sri Lanka, India, and Maine, New Hampshire, Connecticut, North Carolina, and Colorado in the U.S. Heat treatment is commonly used to improve the colour of gem beryls.
aquarium Receptacle for maintaining aquatic organisms, either fresh¬ water or marine, or a facility in which a collection of aquatic organisms is displayed or studied. The first display aquarium opened in Regent’s Park, England, in 1853. Many of the world’s principal cities now have public aquariums as well as commercial ones; other aquarium facilities serve chiefly as research institutions. Regardless of size—whether a small one-gallon jar or a huge million-gallon tank—aquariums must be con¬ structed with care; many substances, especially plastics and adhesives, that are nontoxic to humans are toxic to water-breathing animals. The pri¬ mary requirement for maintaining aquatic organisms is water quality.