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Arcadia (California, United States)
city, Los Angeles county, California, U.S. It lies at the base of the San Gabriel Mountains. The region had been inhabited by Tongva (or Gabrielino) Indians before it became part of the original Mission San Gabriel Arcángel holding. The city was laid out in 1888...
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Arcadia, Academy of (Italian literary academy)
Italian literary academy founded in Rome in 1690 to combat Marinism, the dominant Italian poetic style of the 17th century. The Arcadians sought a more natural, simple poetic style based on the classics and particularly on Greek and Roman pastoral poetry....
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Arcadia, Accademia dell’ (Italian literary academy)
Italian literary academy founded in Rome in 1690 to combat Marinism, the dominant Italian poetic style of the 17th century. The Arcadians sought a more natural, simple poetic style based on the classics and particularly on Greek and Roman pastoral poetry....
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Arcadia Conference (European-United States history)
After Pearl Harbor, Churchill requested an immediate conference with Roosevelt. The two met for three weeks at the Arcadia Conference in Washington after Dec. 22, 1941. They reaffirmed the “Europe first” strategy and conceived “Gymnast,” a plan for Anglo-American landings in North Africa. They also created a Combined Chiefs of Staff Committee and issued, on Jan. 1, 1942...
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Arcádia Lusitana (Portuguese literary society)
In 1756 António Dinis da Cruz e Silva and others established the Arcádia Lusitana, its first aim being the uprooting of Gongorism, a style studded with Baroque conceits and Spanish influence in general. Cruz e Silva’s mock-heroic poem O Hissope (1768), inspired by the French poet Nicolas Boileau’s mock epic ...
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Arcadian League (Greek history)
Confederation of ancient Greek city-states of Arcadia. Arcadian towns had been forced to ally with Sparta by 550 bc, and most Arcadians remained faithful to Sparta during the Peloponnesian War (431–404 bc). In an effort to contain Sparta, Epaminondas of Thebes founded the city-state of Megalopolis...
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Arcadius (Roman emperor)
Eastern Roman emperor conjointly with his father, Theodosius I, from 383 to 395, then solely until 402, when he associated his son Theodosius II with his own rule. Frail and ineffectual, he was dominated by his ministers, Rufinus, Eutropius, and Anthemius, and by his wife Eudoxia. His empire was a prey to the Goths, and Eudoxia abetted the persecution of the p...
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Arcado-Cypriot (ancient Greek language)
Arcado-Cypriot Group...
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Arcand, Denys (Canadian filmmaker)
French Canadian filmmaker whose movies, most notably Les Invasions barbares (2003; The Barbarian Invasions), embodied his intellectual curiosity and passion for politics, art, and life....
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arcanist (history of pottery)
(from Latin arcanum, “secret”), in the 18th century, a European who knew or claimed to know the secret of making certain kinds of pottery (especially true porcelain), which until 1707 was known only by the Chinese. The secret was discovered in Saxony by Ehrenfried Walter von Tschirnhaus...
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Arcaro, Eddie (American jockey)
American jockey who was the first to ride five Kentucky Derby winners and two U.S. Triple Crown champions (winners of the Kentucky Derby, the Preakness Stakes, and the Belmont Stakes). In 31 years of riding Thoroughbreds (1931–61), he won 549 stakes events, a total of 4,779 races, and more than $30,000,000 in purses. On Feb. 20, 1958,...
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Arcaro, George Edward (American jockey)
American jockey who was the first to ride five Kentucky Derby winners and two U.S. Triple Crown champions (winners of the Kentucky Derby, the Preakness Stakes, and the Belmont Stakes). In 31 years of riding Thoroughbreds (1931–61), he won 549 stakes events, a total of 4,779 races, and more than $30,000,000 in purses. On Feb. 20, 1958,...
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Arcas (rocket)
American jockey who was the first to ride five Kentucky Derby winners and two U.S. Triple Crown champions (winners of the Kentucky Derby, the Preakness Stakes, and the Belmont Stakes). In 31 years of riding Thoroughbreds (1931–61), he won 549 stakes events, a total of 4,779 races, and more than $30,000,000 in purses. On Feb. 20, 1958,...
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Arce, Aniceto (president of Bolivia)
...direct involvement in national political life. Whereas Bolivian presidents under Conservative rule in the 19th century had been either silver magnates themselves (Gregorio Pacheco, 1884–88; Aniceto Arce, 1888–92) or closely associated with such magnates as partners or representatives (Mariano Baptista, 1892–96; Severo Fernández Alonso, 1896–99), the Liberals a...
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Arce, Louis-Armand de Lom d’ (French soldier)
French soldier and writer who explored parts of what are now Canada and the United States and who prepared valuable accounts of his travels in the New World....
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Arce, Manuel José (Central American statesman)
...autonomy; suffrage was restricted to the upper classes, slavery was abolished, and the privileges of the Roman Catholic church were maintained. Manuel José Arce was elected first president in 1825....
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Arcella (protozoan)
...soil. The test has an underlying membrane of chitinous material that is similar to an insect’s exoskeleton. The outer layer may be a brownish chitinoid shell secreted by the inner layer (as in Arcella), sand or solid particles glued together (as in Difflugia), or siliceous plates that are secreted by cytoplasm, pushed out, and cemented in place (as in Euglypha). The ...
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Arcellinida (protozoan)
any member of the protozoan order Arcellinida (formerly Testacida) of the class Rhizopodea. Testaceans are usually encased in one-chambered tests, or shells, and usually found in fresh water, although sometimes they occur in salt water and in mossy soil. The test has an...
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Arcesilaus (Greek philosopher)
philosopher who succeeded Crates as head of the Greek Academy; he introduced a skepticism derived either from Socrates or from Pyrrhon and Timon. Refusing to accept or deny the possibility of certainty in knowing, Arcesilaus advocated a skeptical “suspension of judgment” (epochē). The stoics (who held a theory of “irresistible impressions...
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Arceuthobium (plant)
any plant that is a member of the genus Arceuthobium (family Viscaceae), which contains about 8 to 15 species of small-flowered plants that are parasitic on coniferous trees. The species are distributed primarily throughout the Northern Hemisphere, though a few tropical species are present in the Caribbean, Mediterranean, and Southeast Asian areas....
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Arceuthobium minutissimum (plant)
The common dwarf mistletoe, A. minutissimum, is one of the smallest plants having specialized water-conducting tissues. Its flowering stems extend less than 3 mm (about 18 inch) from its host plant. The fruits of most Arceuthobium species are about 4 mm long, and each contains a bullet-shaped seed covered with a sticky substance. Pressure that......
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arch (architecture)
in architecture and civil engineering, a curved member that is used to span an opening and to support loads from above. The arch formed the basis for the evolution of the vault....
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ARCH (economics)
...caused large fluctuations in prices in stock markets, these were often followed by relative calm and slight fluctuations. Inherent in Engle’s autoregressive conditional heteroskedasticity (known as ARCH) model approach was the concept that, while most volatility is embedded in the random......
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arch bridge
The Romans began organized bridge building to help their military campaigns. Engineers and skilled workmen formed guilds that were dispatched throughout the empire, and these guilds spread and exchanged building ideas and principles. The Romans also discovered a natural cement, called pozzolana, which they used for piers in rivers....
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arch dam (engineering)
The advantages of building a curved dam—thus using the water pressure to keep the joints in the masonry closed—were appreciated as early as Roman times. An arch dam is a structure curving upstream, where the water thrust is transferred either directly to the valley sides or indirectly through concrete abutments. Theoretically, the ideal constant angle arch in a V-shaped valley has a....
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Arch, Joseph (British labour leader)
organizer who became the leader of England’s agricultural labourers....
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arch of aorta (anatomy)
From the paired forward extensions from the heart, the ventral aortas, loops develop between the pharyngeal clefts. These are the aortic arches, which served originally to supply blood to the gills in aquatic vertebrates. The arches are laid down in all vertebrates, six or more being found in cyclostomes and fishes; six are present in the......
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Arch Street Theatre (theatre, Philadelphia, Pennsylvania, United States)
...but he was an indifferent manager and often absented himself for extensive tours. In 1861 the theatre’s owner prevailed upon Louisa Drew to assume the management, and it was reopened as Mrs. John Drew’s Arch Street Theatre. For 31 years she remained as manager. She quickly built up one of the most brilliant repertory companies in the history of the American stage. It lasted until....
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Archadelt, Jacob (French composer)
composer who helped establish the musical form of the madrigal....
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Archadente, Jacob (French composer)
composer who helped establish the musical form of the madrigal....
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Archadet, Jacob (French composer)
composer who helped establish the musical form of the madrigal....
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Archaea (bacteria)
any of a group of single-celled prokaryotic organisms (that is, organisms whose cells lack a defined nucleus) that have distinct molecular characteristics separating them from bacteria (the other, more prominent group of prokaryotes) as well as from eukaryotes (organisms, including plants...
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archaea (bacteria)
any of a group of single-celled prokaryotic organisms (that is, organisms whose cells lack a defined nucleus) that have distinct molecular characteristics separating them from bacteria (the other, more prominent group of prokaryotes) as well as from eukaryotes (organisms, including plants...
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Archaean Eon (geochronology)
the earlier of the two divisions of Precambrian time (about 4 billion to 542 million years ago). The Archean Eon began about 4 billion years ago with the formation of the Earth’s crust and extended to the start of the Proterozoic Eon 2.5 billion years ago; the latter is the second division of Precambrian time. Recor...
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archaebacteria (bacteria)
any of a group of single-celled prokaryotic organisms (that is, organisms whose cells lack a defined nucleus) that have distinct molecular characteristics separating them from bacteria (the other, more prominent group of prokaryotes) as well as from eukaryotes (organisms, including plants...
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archaebacterium (bacteria)
any of a group of single-celled prokaryotic organisms (that is, organisms whose cells lack a defined nucleus) that have distinct molecular characteristics separating them from bacteria (the other, more prominent group of prokaryotes) as well as from eukaryotes (organisms, including plants...
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archaeobacteria (bacteria)
any of a group of single-celled prokaryotic organisms (that is, organisms whose cells lack a defined nucleus) that have distinct molecular characteristics separating them from bacteria (the other, more prominent group of prokaryotes) as well as from eukaryotes (organisms, including plants...
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archaeobacterium (bacteria)
any of a group of single-celled prokaryotic organisms (that is, organisms whose cells lack a defined nucleus) that have distinct molecular characteristics separating them from bacteria (the other, more prominent group of prokaryotes) as well as from eukaryotes (organisms, including plants...
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Archaeoceti (mammal suborder)
Cetaceans are distant descendants of a group of poorly defined mammals known as condylarths. There is debate as to whether the first cetaceans (archaeocetes) descended from an extinct group of large carnivores called mesonychids or from a group of hoofed herbivores (artiodactyls). The earliest archaeocetes were huge dolphinlike creatures 6 to 10 metres long. Basilosaurus......
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Archaeocyatha (fossil marine organism)
any member of an extinct group of marine organisms of uncertain relationships found as fossils in marine limestones of Late Precambrian and Early Cambrian age (Precambrian time ended about 542 million years ago and was followed by the Cambrian). The archaeocyathid fossils represent the calcareous supporting structure built b...
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archaeocyathid (fossil marine organism)
any member of an extinct group of marine organisms of uncertain relationships found as fossils in marine limestones of Late Precambrian and Early Cambrian age (Precambrian time ended about 542 million years ago and was followed by the Cambrian). The archaeocyathid fossils represent the calcareous supporting structure built b...
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archaeocyte (biology)
...called chloragocytes, that store and metabolize oil and glycogen and produce ammonia and urea. The chloragocytes eventually disintegrate in the coelomic fluid, and their granules are taken up by amoebocytes, which increase in size, becoming large brown bodies that are never eliminated from the body....
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Archaeogastropoda (gastropod order)
...limnic, and terrestrial species.Subclass ProsobranchiaMostly marine limpets or operculate snails; 3 ganglia at visceral loop; orders include Archaeogastropoda (long cerebropleural connectives) and Apogastropoda (bifurcate tentacle nerves, 2 pedal commissures); at least 20,000 species.Subclass......
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Archaeognatha (bristletail)
The oldest known insect fossil for which there is significant remaining structure (head and thorax fragments) is a bristletail (Archaeognatha), estimated to be 390 to 392 million years old. It was discovered on the north shore of Gaspé Bay, Quebec, Can., at a site that was only 10° above the equator during the Devonian time of this insect....
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Archaeolemuridae (primate family)
...(sloth lemurs)4 genera and 5 species from Madagascar, all extinct within the past 2,000 years. Holocene.Family Archaeolemuridae (baboon lemurs) 2 recently extinct genera and 3 species from Madagascar, all extinct within the past 2,000 ye...
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archaeological chronology
chronology that describes a period of human or protohuman prehistory. Some archaeological timescales are based on relative dating techniques, such as stratigraphy, which illuminate a sequence of change. Others are based on chronometric (absolute) methods such as carbon-14 dating and dendrochronolo...
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archaeological museum
...interest in antiquities led to the excavation of local archaeological sites and had an impact on museum development. In the years 1806–26, in Russian lands to the north of the Black Sea, four archaeological museums were opened, at Feodosiya, Kerch, Nikolayev, and Odessa (all now located in Ukraine). The Museum of Northern Antiquities was opened in Copenhagen in 1819 (it was there that it...
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Archaeological Museum at Olympia (museum, Olympia, Greece)
...of the Statue of Zeus. In the late 20th century, research was conducted primarily by the German Archaeological Institute in Athens and the Ephorate (Magistrate) of Antiquities in Olympia. The Archaeological Museum at Olympia opened in its present location in 1982....
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Archaeological Museum of Barcelona and Institute of Prehistory and Archaeology (museum, Barcelona, Spain)
institution in Barcelona, Spain, notable for its collection of prehistoric objects and for its collection of ancient Greek and Roman art and examples illustrating Iberian archaeology. Exhibits include a scale model of a part of the excavation at Ampurias (Emporiae) and displays of Greek vases, glass, and sculpture. There is a fine statue of Asclepius of the 4th century ...
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Archaeological Museum of Istanbul (museum, Istanbul, Turkey)
Hamdi Bey founded the Archaeological Museum of Istanbul and became its director in 1881. His enlightened taste and energy did much to establish the reputation of the museum and its impressive collection of Greco-Roman antiquities. Included among the treasures that he secured for the museum are the famous Greek sarcophagi found in the royal necropolis at Sidon (now in Lebanon) in 1887. These are......
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Archaeological Museum of Piraeus (museum, Piraeus, Greece)
...of the royal and satrapal courts. At Athens itself, the great magnet for immigrants was naturally Piraeus, the city’s densely populated, multilingual, multiracial port. Bilingual inscriptions in the Archaeological Museum of Piraeus, in Greek and Aramaic, testify to the presence of Phoenician traders, who also left more strictly epigraphic traces. (Conversely, Greco-Aramaic stelae in the....
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archaeological reconnaissance
In order to systematically document and interpret the material remains of past societies, archaeologists have developed a common set of methods and procedures. These include archaeological survey (reconnaissance), excavation, and detailed analysis of recovered artifacts. Survey, or the discovery and recording of archaeological sites or other human-created features, such as roads and irrigation......
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archaeological survey
In order to systematically document and interpret the material remains of past societies, archaeologists have developed a common set of methods and procedures. These include archaeological survey (reconnaissance), excavation, and detailed analysis of recovered artifacts. Survey, or the discovery and recording of archaeological sites or other human-created features, such as roads and irrigation......
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archaeological timescale
chronology that describes a period of human or protohuman prehistory. Some archaeological timescales are based on relative dating techniques, such as stratigraphy, which illuminate a sequence of change. Others are based on chronometric (absolute) methods such as carbon-14 dating and dendrochronolo...
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archaeology
the scientific study of the material remains of past human life and activities. These include human artifacts from the very earliest stone tools to the man-made objects that are buried or thrown away in the present day: everything made by human beings—from simple tools to complex machines, from the earliest houses and...
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Archaeomeryx (prehistoric mammal)
A possible ruminant ancestor was Archaeomeryx from the upper Eocene of China, a small animal that already had a fused naviculo-cuboid bone in the ankle. Tragulids occurred in Africa and Eurasia back to the Miocene, and the more advanced gelocids are known from the upper Eocene and lower Oligocene. At the end of the Oligocene, the first ruminants began to appear with teeth more advanced......
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Archaeopteris (fossil plant genus)
genus of plants that was probably the first true tree to form forests during the Late Devonian Epoch (about 385 to 359 million years ago). Fossils of Archaeopteris confirm the presence of a woody trunk and branching patterns similar to those of modern conifers, but with ...
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Archaeopteryx (fossil bird)
the oldest-known fossil animal that is generally accepted as a bird. The eight known fossil specimens date to the Late Jurassic Period (161 million to 146 million years ago), and all were found in the Solnhofen Limestone Formation in Bavaria, Germany. Here a very fine-grained Jurassic limestone formed in a shallow tropical...
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Archaeopteryx lithographica (fossil bird)
the oldest-known fossil animal that is generally accepted as a bird. The eight known fossil specimens date to the Late Jurassic Period (161 million to 146 million years ago), and all were found in the Solnhofen Limestone Formation in Bavaria, Germany. Here a very fine-grained Jurassic limestone formed in a shallow tropical...
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Archaeornithes (bird subclass)
...feathers; scales on feet; 4-chambered heart; no teeth; horny beak; lungs with extended air sacs; 12 pairs of cranial nerves; internal fertilization; oviparous.Subclass Archaeornithes†Extinct; teeth in both jaws; long, feathered tail; less specialized for flight; body elongated and reptilelike; forelimb had 3 clawed digits; smal...
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Archaeosigillaria (fossil plant)
...in the Sahara. Traces also have been discovered in parts of Guinea, Ghana, and Arabia, as well as in Gabon; they also occur in the Bokkeveld Series of South Africa. Fossilized plants that include Archaeosigillaria (ancient club mosses) may be traced in formations of the earlier Devonian Period in the Sahara and in South Africa......
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Archaeosporales (order of fungi)
...of chitin.Class GlomeromycetesArbuscular mycorrhizal; single or clustered spores; contains four orders.Order ArchaeosporalesArbuscular mycorrhizal; spores form singly or in loose clusters; example genera include Archaeospora and......
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Archaeostraca (crustacean)
...bearing a pair of appendages; about 22,000 species.Subclass PhyllocaridaEarly Cambrian to present.†Order ArchaeostracaDevonian to Triassic.†Order......
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Archaic Chinese language
Some scholars divide the history of the Chinese languages into Proto-Sinitic (Proto-Chinese; until 500 bc), Archaic (Old) Chinese (8th to 3rd century bc), Ancient (Middle) Chinese (through ad 907), and Modern Chinese (from c. the 10th century to modern times). The Proto-Sinitic period is the period of the most ancient inscriptions and poetry; most l...
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Archaic culture
any of the ancient cultures of North or South America that developed from Paleo-Indian traditions and led to the adoption of agriculture. Archaic cultures are defined by a group of common characteristics rather than a particular time period or location; in Mesoamerica, Archaic cultures existed from approximately 8,000...
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Archaic Greek lyric (poetry)
...of the future before the final encounter between Octavian and Mark Antony, and the weariness of the people of Italy in the face of continuing violence. In doing so, he drew near to the ideals of the Archaic Greek lyric, in which the poet was also the bard of the community, and the poet’s verse could be expected to have a political effect. In his erotic Epodes, Horace began.....
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Archaic period (art history)
in history and archaeology, the earliest phases of a culture; the term is most frequently used by art historians to denote the period of artistic development in Greece from about 650 to 480 bc, the date of the Persian sack of Athens....
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Archaic smile (Greek sculpture)
the smile that characteristically appears on the faces of Greek statues of the Archaic period (c. 650–480 bc), especially those from the second quarter of the 6th century bc....
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archaism (linguistics)
...innovation) appears among only one section of the speakers of a language, this automatically creates a dialectal difference. Sometimes an innovation in dialect A contrasts with the unchanged usage (archaism) in dialect B. Sometimes a separate innovation occurs in each of the two dialects. Of course, different innovations will appear in different dialects, so that, in comparison with its......
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Archangel (Russia)
city and administrative centre of Arkhangelsk oblast (province), Russia, on the Northern Dvina River, 30 miles (50 km) from the White Sea. With its suburbs, Solombala and Ekonomiya, the city extends for 10 miles along the river. Founded in 1584 as the fortified monastery of the archangel Michael, it was the first po...
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archangel (religion)
any of several chiefs, rulers, or princes of angels in the hierarchy of angels of the major Western religions, especially Judaism, Christianity, and Islām, and of certain syncretic religions, such as Gnosticism. See angel....
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Archangel Cathedral (cathedral, Moscow, Russia)
...15th-century icons attributed to Theophanes the Greek and to Andrey Rublyov, considered by many to be the greatest of all Russian icon painters. The third cathedral, dedicated to St. Michael the Archangel, was rebuilt in 1505–08; in it are buried the princes of Moscow and the tsars of Russia (except Boris Godunov) up to the founding of St. Petersburg....
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Archangel Michael, Legion of the (Romanian organization)
Romanian fascist organization that constituted a major social and political force between 1930 and 1941. In 1927 Corneliu Zelea Codreanu founded the Legion of the Archangel Michael, which later became known as the Legion or Legionary Movement; it was committed to the “Christian and racial” re...
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Archangel tar
...of wood distillation. Resinous wood tars differ from hardwood tar in containing the pleasant-smelling mixture of terpenes known as turpentine. Pine-wood tar, commonly called Stockholm, or Archangel, tar, is made extensively in the forests of Russia, Sweden, and Finland. It is the residue after the turpentine has been distilled, usually with...
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archbishop (ecclesiastical title)
in the Christian church, a bishop who, in addition to his ordinary episcopal authority in his own diocese, usually has jurisdiction (but no superiority of order) over the other bishops of a province. The functions of an archbishop developed out of those of the metropolitan, a bishop presiding over a number of dioceses in a province, though the title of archbishop, when it first...
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Archbishop Laud, 1573–1645 (work by Trevor-Roper)
Trevor-Roper graduated from Christ Church College, Oxford, in 1936, and in 1939, as a research fellow at Merton College, he qualified for the M.A. degree. His first book was Archbishop Laud, 1573–1645 (1940), a biography of the archbishop of Canterbury and adviser to King Charles I. During World War II,......
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Archboldia papuensis (bird)
...or “platform,” type consists of a thick pad of plant material, ringed or hung about with objects, made by Archbold’s bowerbird (Archboldia papuensis). The stagemaker, or tooth-billed catbird (Scenopoeetes dentirostris), of forests of northeastern Australia, arranges leaves silvery-side up (withered o...
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Archbold’s bowerbird (bird)
...or “platform,” type consists of a thick pad of plant material, ringed or hung about with objects, made by Archbold’s bowerbird (Archboldia papuensis). The stagemaker, or tooth-billed catbird (Scenopoeetes dentirostris), of forests of northeastern Australia, arranges leaves silvery-side up (withered o...
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archchancellor (diplomatics)
...empire early in the 10th century, the German royal chancery developed the organization that was to characterize it throughout the remainder of the Middle Ages. The heads of the chancery were the archchancellors, but the office was entirely honorary and soon came to be automatically held, as far as Germany was concerned, by whoever was archbishop of Mainz. When the German kings or emperors......
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archdeacon (ecclesiastical title)
in the Christian church, originally the chief deacon at the bishop’s church; during the European Middle Ages, a chief official of the diocese; an honorary title in the modern Roman Catholic church. The name was first used in the 4th century, although a similar office existed in the very early church. Appointed by the...
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archdiocese
The archdiocese was divided into dioceses, each ruled by a bishop, who supervised his own administration and episcopal court. In ecclesiastical tradition, bishops were considered the successors of the Apostles, and a strong sense of episcopal collegiality between pope and bishops survived well into the age of increased papal authority. Episcopal courts included a chancery for the use of the......
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archduchess (Habsburg title)
a title, proper in modern times for members of the house of Habsburg. The title of archduke Palatine (Pfalz-Erzherzog) was first assumed by Rudolf IV, Duke of Austria, on the strength of a forged privilege, in the hope of gaining for the dukes of Austria an equal status with the electors of the Holy R...
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archduke (Habsburg title)
a title, proper in modern times for members of the house of Habsburg. The title of archduke Palatine (Pfalz-Erzherzog) was first assumed by Rudolf IV, Duke of Austria, on the strength of a forged privilege, in the hope of gaining for the dukes of Austria an equal status with the electors of the Holy R...
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arche (philosophy)
Another phrase used by Bradley in his preliminary discussion of metaphysics is “the study of first principles,” or ultimate, irrefutable truths....
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Archean Eon (geochronology)
the earlier of the two divisions of Precambrian time (about 4 billion to 542 million years ago). The Archean Eon began about 4 billion years ago with the formation of the Earth’s crust and extended to the start of the Proterozoic Eon 2.5 billion years ago; the latter is the second division of Precambrian time. Recor...
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arched belly (musical instrument)
The arched belly or soundboard of the violin and its relatives is supported in a curiously unorthodox and individual way, quite different from the regular barring of instruments with flat soundboards. The sound post has already been mentioned. It is a loose stick of pine, carefully cut to size, that is wedged between the plates of the finished instrument under, but a little behind, the......
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arched harp (musical instrument)
musical instrument in which the neck extends from and forms a bow-shaped curve with the body. One of the principal forms of harp, it is apparently also the most ancient: depictions of arched harps survive from Sumer and Egypt from ab...
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archegonia (plant anatomy)
the female reproductive organ in ferns and mosses. An archegonium also occurs in some gymnosperms, e.g., cycads and conifers. A flask-shaped structure, it consists of a neck, with one or more layers of cells, and a swollen base—the venter—which contains the egg. Neck-canal cells, located above the egg, disappear as the ...
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archegonium (plant anatomy)
the female reproductive organ in ferns and mosses. An archegonium also occurs in some gymnosperms, e.g., cycads and conifers. A flask-shaped structure, it consists of a neck, with one or more layers of cells, and a swollen base—the venter—which contains the egg. Neck-canal cells, located above the egg, disappear as the ...
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Archelaus (king of Cappadocia)
last king of Cappadocia (reigned 36 bc–c. ad 17), a Roman client during the late republic and the early empire....
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Archelaus (king of Judaea)
son and principal heir of Herod I the Great as king of Judaea, deposed by Rome because of his unpopularity with the Jews....
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Archelaus (king of Macedonia)
king of Macedonia from 413 to 399....
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Archelaus Sisines (king of Cappadocia)
last king of Cappadocia (reigned 36 bc–c. ad 17), a Roman client during the late republic and the early empire....
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Archelon (fossil sea turtle)
extinct giant sea turtle known from fossilized remains found in North American rocks of the Late Cretaceous epoch (100 million to 66 million years ago). Archelon, protected by a shell similar to that found in modern sea turtles, reached a length of about 3.5 m (12 feet). The front feet evolved into powerful structures that could efficiently propel the great bulk of Archelon through t...
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archenteron (anatomy)
...embryo converts the initially single-layered embryo into a two-layered one, a process called gastrulation. The new inner layer of cells, called endoderm (sometimes entoderm), surrounds a cavity, the archenteron, which has an opening to the exterior at the point at which invagination occurred; this opening is called the blastopore. The archenteron eventually becomes the cavity of the ......
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archeology
the scientific study of the material remains of past human life and activities. These include human artifacts from the very earliest stone tools to the man-made objects that are buried or thrown away in the present day: everything made by human beings—from simple tools to complex machines, from the earliest houses and...
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Archeozoic Eon (geochronology)
the earlier of the two divisions of Precambrian time (about 4 billion to 542 million years ago). The Archean Eon began about 4 billion years ago with the formation of the Earth’s crust and extended to the start of the Proterozoic Eon 2.5 billion years ago; the latter is the second division of Precambrian time. Recor...
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Archer (missile)
...a medium-range missile similar to the Amos, apparently had passive radar guidance designed to home onto carrier-wave emissions from U.S. aircraft firing the semiactive radar-homing Sparrow. The AA-11 Archer was a short-range missile used in combination with the Amos and Alamo....
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Archer (constellation)
(Latin: “Archer”), in astronomy, zodiacal constellation lying between Capricornus and Scorpius, at about 19 hours right ascension (the coordinate on the celestial sphere analogous to longitude on the Earth) and 25° south declinatio...
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Archer Daniels Midland Co. (American company)
American businesswoman who was named president and CEO of the agricultural processing corporation Archer Daniels Midland Co. (ADM) in 2006....
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