(Translated by https://www.hiragana.jp/)
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  • Apuleius, Lucius (Roman philosopher and scholar)
    Platonic philosopher, rhetorician, and author remembered for The Golden Ass, a prose narrative that proved influential long after his death. The work, called Metamorphoses by its author, narrates the adventures of a young man changed by magic into an ass....
  • Apuleius of Madauros (Roman philosopher and scholar)
    Platonic philosopher, rhetorician, and author remembered for The Golden Ass, a prose narrative that proved influential long after his death. The work, called Metamorphoses by its author, narrates the adventures of a young man changed by magic into an ass....
  • Apulia (region, Italy)
    regione, southeastern Italy. It extends from the Fortore River in the northwest to Cape Santa Maria di Leuca at the tip of the Salentine Peninsula (the “heel” of Italy) and comprises the provincie of Foggia, Bari, Taranto, Brindisi, and Lecce. The northern third of the region is centred on the Puglia Tableland, which is flanked on the north by the lim...
  • Apulian (people)
    The inhabitants of the southeastern extremity of the Italian peninsula formed a definitely characterized group of populations that the ancients often called Iapyges (whence the geographic term Iapygia, in which “Apulia” may be recognized). The territory included the Salentini and the Messapii peoples in the Salentine Peninsula (ancient Calabia) and the Peucetii and the Dauni farther....
  • Apulian Plain (plain, Italy)
    Plains cover less than one-fourth of the area of Italy. Some of these, such as the Po valley and the Apulian Plain, are ancient sea gulfs filled by alluvium. Others, such as the Lecce Plain in Puglia, flank the sea on rocky plateaus about 65 to 100 ft (20 to 30 m) high, formed of ancient land leveled by the sea and subsequently uplifted. Plains in the interior, such as the long Chiana Valley,......
  • Apulum (ancient city, Romania)
    ...It lies along the Mureş River, 170 miles (270 km) northwest of Bucharest. One of the oldest settlements in Romania, the site was selected by the Romans for a military camp. The remains of Apulum, an important city in Roman Dacia mentioned by Ptolemy in the 2nd century bc, are 6 miles (10 km) from Alba Iulia, and the Regional Museum has a rich collection of Roman antiquities...
  • Apur Sansar (film by Ray)
    ...at the 1956 Cannes International Film Festival. This assured Ray the financial backing he needed to make the other two films of the trilogy: Aparajito (1956; The Unvanquished) and Apur Sansar (1959; The World of Apu). Pather Panchali and its sequels tell the story of Apu, the poor son of a Brahman priest, as he grows from childhood to manhood in a setting......
  • Apure (state, Venezuela)
    estado (state) in the Llanos (plains) of southwestern Venezuela. It is bounded on the north by Táchira, Barinas, and Guárico states and the Apure River, on the east by Bolívar state and the Orinoco River, and on the south and west by Colombia....
  • Apure, Río (river, Venezuela)
    river in western Venezuela. The major navigable tributary of the Orinoco River, it arises in the Cordillera de Mérida and flows for 510 miles (820 km) northeast and east through the heart of the Llanos (plains), Venezuela’s most important cattle-raising area. The river’s principal tributaries, including the Portuguesa and the Guárico, flow mainly from...
  • Apure River (river, Venezuela)
    river in western Venezuela. The major navigable tributary of the Orinoco River, it arises in the Cordillera de Mérida and flows for 510 miles (820 km) northeast and east through the heart of the Llanos (plains), Venezuela’s most important cattle-raising area. The river’s principal tributaries, including the Portuguesa and the Guárico, flow mainly from...
  • Apurímac, Río (river, Peru)
    river in southern Peru. Owing to its lengthy Andean tributaries, it is the farthermost source of the Amazon River. Arising at roughly 17,000 feet (5,200 m) from the snowmelts of Mount Mismi in Arequipa departamento, Peru, it flows northwest through the Andes, descending to less than 860 feet (260 m) to join the Urubamba and form the Ucayali River. For most of its 430-mile (700-kilometre) le...
  • Apurímac River (river, Peru)
    river in southern Peru. Owing to its lengthy Andean tributaries, it is the farthermost source of the Amazon River. Arising at roughly 17,000 feet (5,200 m) from the snowmelts of Mount Mismi in Arequipa departamento, Peru, it flows northwest through the Andes, descending to less than 860 feet (260 m) to join the Urubamba and form the Ucayali River. For most of its 430-mile (700-kilometre) le...
  • apurva (philosophy)
    ...a person to act. Prābhākara defended the ethical theory of duty for its own sake, the sense of duty alone being the proper incentive. The Bhāṭṭas recognize apūrva (supersensible efficacy of actions to produce remote effects) as a supersensible link connecting the moral action performed in this life and the supersensible effect (such as going......
  • Apus affinis (bird)
    India’s population of the house swift has two breeding seasons per year. It is one of the few birds in the world in which this phenomenon has been demonstrated. Adult males are in full breeding condition in late January and again in May and June; eggs are laid in January and February and again in June to September. The molt cycle, however, appears to be independent of the breeding cycle, an...
  • Apus apus (bird)
    ...gray bird that breeds in eastern North America and winters in South America, nesting in such recesses as chimneys and hollow trees; about 17 other Chaetura species are known worldwide. The common swift (Apus apus), called simply “swift” in Great Britain, is a soft-tailed, black bird that breeds across Eurasia and winters in southern Africa, nesting in buildings and.....
  • Apus caffer (bird)
    ...zonaris), soft-tailed and brownish black with a narrow white collar, is found from Mexico to Argentina and on larger Caribbean islands, nesting in caves and behind waterfalls. The white-rumped swift (Apus caffer), soft-tailed and black with white markings, is resident throughout Africa south of the Sahara. The white-throated swift (Aeronautes saxatalis),......
  • Apuseni Mountains (mountains, Romania)
    large mountain chain, a subgroup of the Carpathians, lying north of the Mureş River, northwestern Romania. The Apuseni (Western) Mountains are not high—reaching a maximum elevation of only 6,066 feet (1,849 m)—but as a uniform, imposing group they dominate the low surrounding area. Central to the group, and the highest, is the Bihor Massif, from which radiat...
  • Apuseni, Munţii (mountains, Romania)
    large mountain chain, a subgroup of the Carpathians, lying north of the Mureş River, northwestern Romania. The Apuseni (Western) Mountains are not high—reaching a maximum elevation of only 6,066 feet (1,849 m)—but as a uniform, imposing group they dominate the low surrounding area. Central to the group, and the highest, is the Bihor Massif, from which radiat...
  • aputiak (dwelling)
    temporary winter home or hunting-ground dwelling of Canadian and Greenland Inuit (Eskimos). The term igloo, or iglu, from Eskimo igdlu (“house”), is related to Iglulik, a town, and Iglulirmiut, an Inuit people, both on an island of the same name. The igloo, usually made from blocks of snow and dome-shaped, is used only in the area between the Mackenzie River...
  • Āq Kupruk (Afghanistan)
    ...a transitional Neanderthal skull fragment in association with Mousterian-type tools was discovered; the remains are of the Middle Paleolithic Period, dating to about 30,000 years ago. Caves near Āq Kupruk yielded evidence of an early Neolithic culture (c. 9000–6000 bc) based on domesticated animals. Archaeological research since World War II has revealed Bronze Age s...
  • Aq Qoyunlu (Turkmen tribal federation)
    Turkmen tribal federation that ruled northern Iraq, Azerbaijan, and eastern Anatolia from ad 1378 to 1508....
  • Āqā Khān (Muslim title)
    ...and Bohra merchant communities of India and easternAfrica. The Khojas, who are descended from the Nizārī branch of the Ismāʿīlīs, continue to follow the aga khans, a lineage of Muslim spiritual leaders who claim direct descent from ʿAlī. Another Ismāʿīlī dynasty, the Qarmatians, was active...
  • Āqā Mīrak (Persian painter)
    Persian painter, an admired portraitist and an excellent colourist, who painted in a sumptuous style....
  • Āqā Rezā Rezā-e ʿAbbāsī (Persian painter)
    the major Persian painter of the Eṣfahān school and the favourite painter of Shāh ʿAbbās I the Great....
  • Aqaba (Jordan)
    port town, extreme southwestern Jordan. It lies on the Gulf of Aqaba, an inlet of the Red Sea, just east of the Jordan-Israel frontier on the gulf. It is Jordan’s only seaport. Because of freshwater springs in the vicinity, it has been settled for millennia; King Solomon’s port and foundry of Ezion-geber lay nearby....
  • Aqaba, Gulf of (gulf, Red Sea)
    northeastern arm of the Red Sea, penetrating between Saudi Arabia and the Sinai Peninsula. It varies in width from 12 to 17 miles (19 to 27 km) and is 110 miles (177 km) long....
  • ʿAqabah, Al- (Jordan)
    port town, extreme southwestern Jordan. It lies on the Gulf of Aqaba, an inlet of the Red Sea, just east of the Jordan-Israel frontier on the gulf. It is Jordan’s only seaport. Because of freshwater springs in the vicinity, it has been settled for millennia; King Solomon’s port and foundry of Ezion-geber lay nearby....
  • ʿAqarqūf (ancient city, Iraq)
    fortified city and royal residence of the later Kassite kings, located near Babylon in southern Mesopotamia (now in Iraq). This city was founded either by Kurigalzu I (c. 1400–c. 1375 bc) or by Kurigalzu II (c. 1332–08). Between ad 1943 and 1945, Iraqi excavations unearthed a monumental ziggurat, three temples, and a...
  • AQHA (American organization)
    For years little attempt was made to develop a distinct breed. In 1940, however, the American Quarter Horse Association (AQHA) was organized, and in 1950 it was reorganized to include other Quarter Horse organizations. The AQHA controls the American Quarter Horse Stud Book and Registry. With more than 2.5 million horses registered in its stud book by the late 20th century, the AQHA was......
  • Aqhat Epic (ancient Semitic legend)
    ancient West Semitic legend probably concerned with the cause of the annual summer drought in the eastern Mediterranean. The epic records that Danel, a sage and king of the Haranamites, had no son until the god El, in response to Danel’s many prayers and offerings, finally granted him a child, whom Danel named Aqhat. Some time later Danel offered hospitality to the divine...
  • ʿāqil (Islamic law)
    (Arabic: “knowledgeable”), in Islāmic law, one who is in full possession of his mental faculties. Such a person is legally responsible for his actions and punishable for any deviation from religious commandments. ʿĀqil is often used with the adjective bāligh (“grown-up,” or “of age”) in contrast to qā...
  • aqın (bard)
    By the 17th century, if not before, there had emerged two types of professional bards: the zhıraw and the aqın. These were primarily—though not exclusively—male professions. The zhıraw performed both the epic zhır and the didactic tolgaw and.....
  • ʿaql (Druze theology)
    Each principle had a human counterpart from among al-Ḥākim’s contemporaries. Ḥamzah himself became the first principle, or ḥadd, Universal Intelligence (al-ʿAql); al-ʿAql generated the Universal Soul (an-Nafs), embodied in Ismāʿīl ibn Muḥammad at-Tamīmī. The Word (al-Kalimah) emanates from an-Nafs and...
  • Aqmar Mosque, Al- (mosque, Cairo, Egypt)
    ...is rather the patronage of lower officials and of the bourgeoisie, if not even of the humbler classes, that was responsible for the most interesting Fāṭimid buildings. The mosques of al-Aqmar (1125) and of al-Ṣāliḥ (c. 1160) are among the first examples of monumental small mosques constructed to serve local needs. Even though their internal......
  • Aqmola (Kazakhstan)
    city, capital of Kazakhstan. Astana (meaning “Capital” in Kazak) lies in north-central Kazakhstan along the Ishim River at the junction of the Trans-Kazakhstan and South Siberian railways....
  • ʿAqqād, ʿAbbās Maḥmūd al- (Egyptian author)
    Egyptian journalist, poet, and literary critic who was an innovator of 20th-century Arabic poetry and criticism....
  • ʿAqrabāʾ, Battle of (633)
    ...converted. The major campaign was directed against Abū Bakr’s strongest opponent, the prophet Musaylimah and his followers in Al-Yamāmah. It culminated in a notoriously bloody battle at ʿAqrabāʾ in eastern Najd (May 633), afterward known as the Garden of Death. The encounter cost the Muslims the lives of many ansar (disciples of the Prophet) who were in...
  • Aqṣā Intifāḍah (Palestinian-Israeli history)
    The failure of the Camp David summit and the outbreak of what came to be known as the Aqṣā intifāḍah convinced a majority of Israelis that they lacked a partner in ʿArafāt to end the conflict. Barak paid the political price, losing the premiership to Sharon by nearly 25 percent of the vote in elections held in Februar...
  • Aqṣā Mosque, Al- (mosque, Jerusalem)
    ...structure consisting of a wooden dome set on a high drum and resting on four tiers and 12 columns. The Umayyad ruler al-Walīd (died 715) built the great mosque at Damascus and al-Aqṣā Mosque at Jerusalem with two tiers of arcades in order to heighten the ceiling. The early Syro-Egyptian mosque is a heavily columned structure with a prayer niche......
  • Aqsū River (river, Kazakstan)
    ...80–90 percent of the total influx into the lake until a hydroelectric project reduced the volume of the river’s inflow late in the 20th century. Only such small rivers as the Qaratal, Aqsū, Ayaguz, and Lepsi feed the eastern part of the lake. With almost equal areas in both parts of the lake, this situation creates a continuous flow of water from the western to the eastern....
  • Aqtöbe (Kazakstan)
    city, northwestern Kazakhstan, on the Ilek River. It was founded in 1869 as Aktyube (“White Hill”), a small Russian fort; the first Russian peasant settlers arrived in 1878. In 1891 it became the capital of an uyezd (canton) and in 1932 of an oblast (province). During World War II a ferroalloys plant was built to smelt the nickel and chromium ores of the Mughalzhar (Mug...
  • Aqtöbe (oblast, Kazakstan)
    ...such as Qaraghandy province, because Soviet authorities never seriously made environmental protection a high priority. In the vicinity of the Aral Sea, and especially in Qyzylorda (Kzyl-Orda) and Aqtöbe provinces, Kazakhs suffer from the pollution and salinization of the sea. Its waters are contaminated with pesticides, especially DDT, and with chemical fertilizer fed into it by various....
  • Aqua (building, Chicago, Illinois, United States)
    ...such as Qaraghandy province, because Soviet authorities never seriously made environmental protection a high priority. In the vicinity of the Aral Sea, and especially in Qyzylorda (Kzyl-Orda) and Aqtöbe provinces, Kazakhs suffer from the pollution and salinization of the sea. Its waters are contaminated with pesticides, especially DDT, and with chemical fertilizer fed into it by various....
  • aqua ammonia (chemical compound)
    solution of ammonia gas in water, a common commercial form of ammonia. It is a colourless liquid with a strong characteristic odour. In concentrated form, ammonium hydroxide can cause burns on contact with the skin; ordinary household ammonia, used as a cleanser, is dilute ammonium hydroxide....
  • aqua complex
    Few ligands equal water with respect to the number and variety of metal ions with which they form complexes. Nearly all metallic elements form aqua complexes, frequently in more than one oxidation state. Such aqua complexes include hydrated ions in aqueous solution as well as hydrated salts such as hexaaquachromium(3+) chloride, [Cr(H2O)6]Cl3. For metal ions......
  • aqua fortis (chemical compound)
    (HNO3), colourless, fuming, and highly corrosive liquid (freezing point -42° C [-44° F], boiling point 83° C [181° F]) that is a common laboratory reagent and an important industrial chemical for the manufacture of fertilizers and explosives. It is toxic and can cause severe burns....
  • aqua regia (chemistry)
    mixture of concentrated nitric and hydrochloric acids, usually one part of the former to three parts of the latter by volume. This mixture was given its name (literally, “royal water”) by the alchemists because of its ability to dissolve gold and other so-called noble metals....
  • aqua vitae (alcoholic beverage)
    alcoholic beverage (such as brandy, whisky, rum, or arrack) that is obtained by distillation from wine or other fermented fruit or plant juice or from a starchy material (such as various grains) that has first been brewed. The alcoholic content of distilled liquor is higher than that of beer or wine....
  • Aqua-Lung (diving gear)
    ...the founder of the Underseas Research Group at Toulon and of the French Office of Underseas Research at Marseille, Fr. (renamed the Centre of Advanced Marine Studies in 1968). The inventor of the Aqua-Lung diving apparatus and a process for using television underwater, he became head in 1957 of the Conshelf Saturation Dive Program, conducting experiments in which men live and work for......
  • aquaculture (horticulture)
    the cultivation of plants in nutrient-enriched water, with or without the mechanical support of an inert medium such as sand or gravel....
  • aquaculture (fishery)
    an approximate equivalent in fishing to agriculture—that is, the rearing of fish, shellfish, and some aquatic plants to supplement the natural supply. Fish are reared under controlled conditions all over the world....
  • Aquae Cumanae (historic site, Italy)
    ancient city of Campania, Italy, located on the west coast of the Gulf of Puteoli (Pozzuoli) and lying 10 miles (16 km) west of Naples and 212 miles (4 km) from Cumae, of which it was a dependency. According to tradition, Baiae was named after Baios, the helmsman of Ulysses. In 178 bc the city is mentioned as Aq...
  • Aquae Gratianae (France)
    city and Alpine spa, Savoie département, Rhône-Alpes région, southeastern France, southwest of Geneva. A summer and winter resort with a beach on Bourget Lake (France’s largest lake) and an aerial cableway up fir-covered Mount Revard (5,125 feet [1,562 metres]), it is a fashionable Alpine spa maintai...
  • Aquae Helveticae (Switzerland)
    town, Aargau canton, northern Switzerland, on the Limmat River, northwest of Zürich. The hot sulfur springs, mentioned as early as the 1st century ad by the Roman historian Tacitus, still attract large numbers of people. The town, founded by the Habsburgs in 1291, was conquered in 1415 (with Aargau) by the Swiss Confederation. The Diet of the Swiss Confeder...
  • Aquae Mattiacae (Germany)
    city, capital of Hesse Land (state), southern Germany. It is situated on the right (east) bank of the Rhine River at the southern foot of the Taunus Mountains, west of Frankfurt am Main and north of Mainz. The settlement was known as a spa (Aquae ...
  • Aquae Sulis (England, United Kingdom)
    city, unitary authority of Bath and North East Somerset, historic county of Somerset, England. Bath lies along the River Avon in a natural amphitheatre of steep hills. Built of local limestone, it is one of the most elegant and architecturally distinguished of British cities. Its 16th-century abbey church of St. Peter and St. Paul is late Perpendicular Gothic ...
  • Aquae Tarbellicae (France)
    town, Landes département, Aquitaine région, southwestern France. It lies on the left bank of the Adour River, 88 miles (142 km) southwest of Bordeaux and 50 miles (80 km) north of the Pyrenees frontier with Spain. The town is a spa resort whose thermal springs and mud baths have been noted for the cure of rheumatism since Roman times, when it was know...
  • aqualung (diving gear)
    ...the founder of the Underseas Research Group at Toulon and of the French Office of Underseas Research at Marseille, Fr. (renamed the Centre of Advanced Marine Studies in 1968). The inventor of the Aqua-Lung diving apparatus and a process for using television underwater, he became head in 1957 of the Conshelf Saturation Dive Program, conducting experiments in which men live and work for......
  • Aquaman (fictional character)
    American comic-strip superhero, defender of the underwater kingdom of Atlantis, and sometime member of the superhero consortium Justice League of America. Aquaman made his debut in 1941 in the anthology series More Fun Comics and since that time has appeared in numerous DC Comics magazines....
  • aquamanile (pitcher)
    Some of the finest bronze articles of the High Middle Ages were modelled on Oriental pieces brought back from the Holy Land by the crusaders. They are known as aquamaniles, a type of ewer used for pouring water for washing one’s hands. Made by bronze casters in France, Germany, England, and Scandinavia, they are usually in the shape of lions—symbols of valour, pride, physical strengt...
  • aquamarine (gemstone)
    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 pegmatite, in which it forms much larger and clearer crystals than emerald (one completely transparent crystal from Brazil weighed 110 kg [243 pounds]). It can also be found in mica schists. Aquamarine occurs in Brazil, which is the chief source; ...
  • aquaplane (sport)
    Water skis derive from the aquaplane, a wide riding board towed by a motorboat. Aquaplanes were most popular in the United States, France, and Switzerland, the areas in which waterskiing first became popular. Ralph Samuelson, considered the “father” of the sport, was first to water-ski in 1922 at Lake Pepin, Minn. Fred Waller of Long Island, N.Y., received the......
  • aquaporin (protein)
    ...responded when placed in a water solution. He discovered that cells with the protein swelled up as water flowed in, while those lacking the protein remained the same size. Agre named the protein aquaporin. Researchers subsequently discovered a whole family of the proteins in animals, plants, and even bacteria. Two different aquaporins were later found to play a major role in the mechanism by......
  • aquarelle (art)
    technique of painting in transparent, rather than opaque, watercolours. Although aquarelle was known to the ancient Egyptians, it did not achieve popularity in Europe until the 18th and 19th centuries. It was used especially in France and England by landscape painters....
  • aquarium
    receptacle for maintaining aquatic organisms, either freshwater or marine, or a facility in which a collection of aquatic organisms is displayed or studied....
  • Aquarium de Montréal (aquarium, Montreal, Quebec, Canada)
    municipally owned aquarium located on St.-Helen’s Island, Montreal, Can. It was built in 1966 for Expo 67, an international exhibition that was held in the city. The aquarium complex consists of two large buildings, one of which contains exhibits of marine and freshwater fishes and invertebrates. The other building is exclusively for marine mammals. The aquarium’s fish collection is ...
  • Aquarium, L’  (work by Godbout)
    ...structures, derived in part from the French nouveau roman of the previous decade. The Quebec “new novel” began with Jacques Godbout’s L’Aquarium (1962) and reached its high point in the brilliantly convoluted novels of Hubert Aquin that followed his Prochain épisode (1965; “Next Episode...
  • Aquarius (astronomy)
    (Latin: Water Bearer), in astronomy, zodiacal constellation lying between Capricornus and Pisces, at about 23 hours right ascension (the coordinate on the celestial sphere analogous to longitude on the Earth) and 10° south declination (angular distance south of the celestial equator). It lacks striking features, the brightest stars being only of the third magnitude....
  • Aquarius, Age of (United States history)
    ...in liberation theologies drawn from both Western psychology and East Asian religion, psychedelic drugs, rock music, and a “back-to-nature” communal movement. Christened “the Age of Aquarius,” this postmillennial movement peaked in 1968–69 with a series of (largely student) uprisings around the world, from Los Angeles to Paris, that culminated in the Woodstock....
  • aquatic animal
    The prolific zooplankton of Antarctic waters feed on the copious phytoplankton and, in turn, form the basic diet of whales, seals, fish, squid, and seabirds. The Antarctic waters, because of their upwelled nutrients, are more than seven times as productive as subantarctic waters. The most important organism in the higher food chain is the small, shrimplike krill, Euphausia superba, only......
  • aquatic ecosystem
    ...pelagic species (biota living in the open sea) existed, and no organisms inhabited the ocean depths. Life in the shallow regions of the seafloor, however, was already well diversified. This early aquatic ecosystem included the relatively large carnivore Anomalocaris, the deposit-feeding trilobites (early arthropods) and mollusks, the suspension-feeding sponges,......
  • Aquatic industry (ancient African industry)
    The original expansion of the Nilo-Saharan family may have been associated with the Aquatic industry. This industry, which dates to the 8th millennium bc, is a conglomeration of cultures that exploited the food resources of lakes, rivers, and surrounding areas from Lake Rudolf in East Africa to the bend of the Niger River in West Africa during a long era of wetter climate and higher ...
  • aquatic leech (annelid)
    ...young, it may eat oligochaetes. Feeding is facilitated by the secretion of hirudin. The leech detaches after becoming engorged with blood, and it may not attempt to feed again for up to 18 months. Marine leeches attach to, and feed directly from, the gills of fish. Other leeches are carnivorous and feed on oligochaetes and snails....
  • aquatic locomotion
    in animals, movement through water either by swimming or by progression in contact with the substrate (i.e., the bottom or other surfaces)....
  • aquatic plant (botany)
    Hydrophytic trees have various modifications that facilitate their survival and growth in the aqueous environment. Some species produce a high frequency of lenticels on the bark that facilitate gas exchange. Others exhibit greater permeation of oxygen through the bark and into the cambium at lower oxygen concentrations. Hydrophytic trees often have more intercellular spaces in their tissues to......
  • aquatint (printmaking)
    a variety of etching widely used by printmakers to achieve a broad range of tonal values. The process is called aquatint because finished prints often resemble watercolour drawings or wash drawings. The technique consists of exposing a copperplate to acid through a layer of melted granulated resin. The acid bites away the plate only in the interstices between the resin grains, leaving an evenly pi...
  • aquavit (liquor)
    flavoured, distilled liquor, clear to pale yellow in colour, dry in flavour, and ranging in alcohol content from about 42 to 45 percent by volume. It is distilled from a fermented potato or grain mash, redistilled in the presence of flavouring agents, filtered with charcoal, and usually bottled without aging. Various aromatic flavourings are employed, usually including caraway o...
  • aquavite (liquor)
    flavoured, distilled liquor, clear to pale yellow in colour, dry in flavour, and ranging in alcohol content from about 42 to 45 percent by volume. It is distilled from a fermented potato or grain mash, redistilled in the presence of flavouring agents, filtered with charcoal, and usually bottled without aging. Various aromatic flavourings are employed, usually including caraway o...
  • Aquaviva, Claudio (Jesuit leader)
    fifth and youngest general of the Society of Jesus, considered by many to have been the order’s greatest leader. The youngest son of the Duke of Atri, he joined the order in 1567. Shortly after completing his studies he was appointed provincial superior of Naples and then of Rome....
  • aqueduct (engineering)
    man-made conduit for carrying water (Latin aqua, “water,” and ducere, “to lead”). In a more restricted sense, aqueducts are structures used to conduct a water stream across a hollow or valley. In modern engineering “aqueduct” refers to a system of pipes, ditches, canals, tunnels, and supporting structures used to convey wat...
  • Aqueduct Bridge (bridge, New York, United States)
    ...supply. In 1836 he took charge of construction of the Croton Aqueduct, New York City’s first water-supply system, and he directed the construction of the Croton Dam and Reservoir as well as the Aqueduct Bridge, which was built on 15 stone arches and crossed the Harlem River. In 1846 Jervis served as the consulting engineer for the Boston water-supply system....
  • Aquem-os-Montes (historical province, Portugal)
    historical provincia, northwesternmost Portugal. It was originally called Entre Douro e Minho, the region between the Minho and Douro rivers. The area was occupied by both the Celts and the Romans, the former having left numerous ruins called castra, or hill forts. There is a narrow coastal plain stretching for about 30 miles (50 km) from north to south and extendi...
  • Aquen, Jerome van (Flemish painter)
    brilliant and original northern European painter of the late Middle Ages whose work reveals an unusual iconography of a complex and individual style. Although at first recognized as a highly imaginative “creator of devils” and a powerful inventor of seeming nonsense full of satirical meaning, Bosch demonstrated insight into the depths of the mind and an ability to depict symbols of l...
  • aqueous humor (physiology)
    optically clear, slightly alkaline liquid that occupies the anterior and posterior chambers of the eye (the space in front of the iris and lens and the ringlike space encircling the lens). The aqueous humour resembles blood plasma in composition but contains less protein and glucose an...
  • aqueous humour (physiology)
    optically clear, slightly alkaline liquid that occupies the anterior and posterior chambers of the eye (the space in front of the iris and lens and the ringlike space encircling the lens). The aqueous humour resembles blood plasma in composition but contains less protein and glucose an...
  • aquiculture (fishery)
    an approximate equivalent in fishing to agriculture—that is, the rearing of fish, shellfish, and some aquatic plants to supplement the natural supply. Fish are reared under controlled conditions all over the world....
  • Aquidneck Island (island, Rhode Island, United States)
    island, largest in Narragansett Bay, eastern Rhode Island, U.S., occupying an area of 44 square miles (114 square km). Aquidneck is the Indian name for what was later called Rhode Island. The source of the modern name is unclear: it either was given by colonist Roger Williams, thinking it was the island (Block Island) the Italian navigator ...
  • aquifer (hydrology)
    in hydrology, rock layer that contains water and releases it in appreciable amounts. The rock contains water-filled pore spaces, and, when the spaces are connected, the water is able to flow through the matrix of the rock. An aquifer also may be called a water-bearing stratum, lens, or zone....
  • Aquifoliaceae (plant family)
    the holly family, in the order Aquifoliales, found worldwide, comprising two genera and about 400 species of shrubs and trees, best known for the genus Ilex (see holly). Four species of Byronia are in the Polynesian and Australian area, and only one species of mountain holly (Nemopanthus mucronatus) is native to northeastern North America....
  • Aquifoliales (plant order)
    holly order of flowering plants, containing more than 500 species in 5 families, mainly Aquifoliaceae. Aquifoliales belongs to the core asterid clade (organisms with a single common ancestor), or sympetalous lineage of flowering plants, in the Asterid II group of the Angiosperm Phylogeny Group II (APG II) botanical classification system (see an...
  • Aquila (ancient biblical scholar)
    scholar who in about ad 140 completed a literal translation into Greek of the Old Testament; it replaced the Septuagint among Jews and was used by the Church Fathers Origen in the 3rd century and St. Jerome in the 4th and 5th centuries. St. Epiphanius (c. 315—403) preserved in his writings the popular Christian tradition that Aquila was a relative of ...
  • Aquila (constellation)
    scholar who in about ad 140 completed a literal translation into Greek of the Old Testament; it replaced the Septuagint among Jews and was used by the Church Fathers Origen in the 3rd century and St. Jerome in the 4th and 5th centuries. St. Epiphanius (c. 315—403) preserved in his writings the popular Christian tradition that Aquila was a relative of ...
  • Aquila chrysaetos (bird)
    (Aquila chrysaetos), dark brown eagle of the family Accipitridae, characterized by golden lanceolate nape feathers (hackles), dark eyes, yellow cere, gray beak, fully feathered legs, large yellow feet, and great talons. Its wingspread reaches 2.3 m (almost 8 feet). It is the national bird of Mexico....
  • Aquila, Juan del (Spanish commander)
    ...join Tyrone at Kinsale was remarkable; in 24 hours he and his men covered no less than 40 miles, including the almost impassable Slieve Phelim Mountains. Red Hugh’s support of the Spanish commander, Juan del Aquila, who counselled an immediate attack against the advice of the more cautious O’Neill, may well have brought about the crushing defeat that may be regarded as the death b...
  • Aquila, L’ (Italy)
    city, capital of Abruzzi region, central Italy. It is situated on a hill above the Aterno River, northeast of Rome. The area was settled by the Sabini, an ancient Italic tribe, after their town Amiternum was destroyed by the Romans and later by the barbarians. The city was founded about 1240 by the Holy Roman emperor Frederick II and became an episcopal see in 1257. An important centre in the Midd...
  • Aquila, Lex (Roman law)
    The provisions of the Twelve Tables concerning damnum injuria datum (property loss) are not known, but in any case they were superseded by the Lex Aquila in the early 3rd century bc. This law covered slaves and animals as well as buildings. If a slave or a grazing animal was unlawfully killed, the damages were equal to the highest value of the slave or animal in the preceding ...
  • Aquila verreauxi (bird)
    Verreaux’s eagle (Aquila verreauxi) is an uncommon bird of eastern and southern Africa. It is black with white rump and wing patches. It reaches about 80 cm (31 inches) in length, and it subsists mainly on hyraxes. See bateleur; golden eagle....
  • Aquilegia (plant)
    any of approximately 80 species of perennial herbaceous plants constituting the genus Aquilegia of the buttercup family (Ranunculaceae) native to Europe and North America. Several species of columbine and a number of hybrids are cultivated for their attractive flowers....
  • Aquilegia caerulea (plant)
    ...tall along roadsides and woodland edges. The species and its several hybrids, which are known for their nodding flowers with short incurved spurs, are cultivated widely in North America. From A. caerulea and A. chysantha, both native to the Rocky Mountains, have been developed many garden hybrids with showy long-spurred flowers in a variety of colours ranging from white to......
  • Aquilegia canadensis (plant)
    ...chysantha, both native to the Rocky Mountains, have been developed many garden hybrids with showy long-spurred flowers in a variety of colours ranging from white to yellow, red, and blue. The wild columbine of North America (A. canadensis) grows in woods and on rocky ledges from southern Canada southward. It is 30 to 90 cm tall. The flowers are red with touches of yellow and are.....

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