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  • Altay (mountain range, Asia)

    Altai Mountains, complex mountain system of Central Asia extending approximately 1,200 miles (2,000 km) in a southeast-northwest direction from the Gobi (Desert) to the West Siberian Plain, through China, Mongolia, Russia, and Kazakhstan. The jagged mountain ridges derive their name from the

  • Altay Nature Reserve (research area, Russia)

    Altaisky Nature Reserve, natural area set aside for research in the natural sciences, in the northeastern Altai Mountains near Lake Teletsky, in south-central Russia. The reserve, established in 1932, has an area of 34,025 square miles (88,124 square km). Its physiographic features include high

  • Altayn Nuruu (mountain range, Asia)

    Altai Mountains, complex mountain system of Central Asia extending approximately 1,200 miles (2,000 km) in a southeast-northwest direction from the Gobi (Desert) to the West Siberian Plain, through China, Mongolia, Russia, and Kazakhstan. The jagged mountain ridges derive their name from the

  • altazimuth system (astronomy)

    astronomical map: The horizon system: The simple altazimuth system, which depends on a particular place, specifies positions by altitude (the angular elevation from the horizon plane) and azimuth (the angle clockwise around the horizon, usually starting from the north). Lines of equal altitude around the sky are called…

  • Altdorf (Switzerland)

    Altdorf, capital of Uri canton, central Switzerland. It lies near the confluence of the Reuss River and the Sch?chen torrent, southeast of Lucerne. In the centre of the town a bronze statue of William Tell (1895) marks the place at which, according to tradition, he shot, with his crossbow, an apple

  • Altdorfer, Albrecht (German artist)

    Albrecht Altdorfer, German painter, printmaker, and draftsman who was one of the founders of landscape painting. Altdorfer spent most of his life in Regensburg, becoming a citizen in 1505 and in later years serving as official architect of the city and a member of its inner council. He was the

  • alte Andreas, Der (work by Kretzer)

    Max Kretzer: …as a sign writer and Der alte Andreas (1911; “Old Andrew”) records his work in a lamp factory. In other novels he treats pressing social problems of the day: prostitution in Die Betrogenen (1882; “The Deceived”); the fate of the urban workers in Die Verkommenen (1883; “The Depraved”); and the…

  • Alte Nationalgalerie (museum, Berlin, Germany)

    Old National Gallery, art museum in Berlin, Ger., noted for its collection of 19th-century European painting and sculpture. The Old National Gallery is one of the museums that make up the world famous National Museums of Berlin, and together with the Old (Altes), Bode, New (Neues), and Pergamon

  • Alte Pinakothek (museum, Munich, Germany)

    Alte Pinakothek, fine art museum in Munich, Ger., noted for its collection of paintings by 14th- to 18th-century European masters. It is one of several institutions that constitute the Bavarian State Picture Galleries. The collection of the Alte Pinakothek (Old Pinakothek) originated in the 1500s

  • alte Turmhahn, Der (work by M?rike)

    Eduard Friedrich M?rike: …remote Württemberg village immortalized in Der alte Turmhahn, where inhabitants and pastor are seen through the whimsical but percipient eyes of an old weathercock. All his life M?rike suffered from psychosomatic illnesses, which were possibly intensified by an unconscious conflict between his humanist aspirations and his church dogmas. When only…

  • alte und der neue Glaube, Der (work by Strauss)

    David Friedrich Strauss: …und der neue Glaube (1872; The Old Faith and the New), in which he ventured to replace Christianity with scientific materialism, a personalized form of Darwinism. Criticized for an inadequate understanding of the biblical and theological texts he criticized, Strauss nevertheless not only influenced 20th-century liberal and eschatological schools of…

  • Altena (Delaware, United States)

    Wilmington, largest city in Delaware, U.S., and seat of New Castle county at the influx of the Christina River and Brandywine Creek into the Delaware River. It is the state’s industrial, financial, and commercial centre and main port. The oldest permanent European settlement in the Delaware River

  • Altenberger, Alida Maria Laura von (Italian actress)

    Alida Valli, (Alida Maria Laura von Altenberger), Italian actress (born May 31, 1921, Pula, Italy [now in Croatia]—died April 22, 2006, Rome, Italy), had roles in more than 100 films, but she was best known outside Italy for her chilling portrayal of Anna Schmidt in the British film-noir classic T

  • Altenburg (Germany)

    Altenburg, city, Thuringia Land (state), central Germany. It lies along the Pleisse River, at the southern edge of the central German brown-coal deposits, south of Leipzig. First mentioned in 976 as the site of a watchtower near an old Slav fortress, it was a trading centre and royal residence in

  • Altencelle (Germany)

    Celle, city, Lower Saxony Land (state), north-central Germany, on the Aller River, at the southern edge of the Lüneburger Heide (Heath), northeast of Hannover. The old town, Altencelle, was founded about 1248, and Celle (founded 1292) was the residence (1371–1705) of the dukes of

  • Altenkirch, E. (German physicist)

    thermoelectric power generator: By 1910 Edmund Altenkirch, a German scientist, satisfactorily calculated the potential efficiency of thermoelectric generators and delineated the parameters of the materials needed to build practical devices. Unfortunately, metallic conductors were the only materials available at the time, rendering it unfeasible to build thermoelectric generators with an…

  • altepetl (Latin American history)

    history of Latin America: Postconquest indigenous society: The local state, the altepetl, with its rotating constituent parts, remained viable as a functioning autonomous unit and as bearer of all major Spanish structural innovations, not only the encomienda but also the parish and the indigenous municipality. The Nahuas accepted Christianity and built large churches for themselves, but…

  • alter ego (mythology)

    myth: The alter ego, or life index: Other religious and folkloric traditions view the life of the human individual as bound up with that of a plant or animal: if one is destroyed the other dies as well. In some traditions, this is confined to the familiar…

  • Alter, Hobart Laidlaw (American surfing and sailing innovator)

    Hobie Alter, (Hobart Laidlaw Alter), American surfing and sailing innovator (born Oct. 31, 1933, Ontario, Calif.—died March 29, 2014, Palm Desert, Calif.), revolutionized the sports of surfing (with his mass-produced lightweight surfboards made of polyurethane foam) and sailing (with his Hobie Cat,

  • Alter, Hobie (American surfing and sailing innovator)

    Hobie Alter, (Hobart Laidlaw Alter), American surfing and sailing innovator (born Oct. 31, 1933, Ontario, Calif.—died March 29, 2014, Palm Desert, Calif.), revolutionized the sports of surfing (with his mass-produced lightweight surfboards made of polyurethane foam) and sailing (with his Hobie Cat,

  • alteration pseudomorph (mineral)

    pseudomorph: formed by substitution, deposition, or alteration. In the formation of a pseudomorph by substitution, the original substance has been gradually removed and simultaneously replaced by another. A common example of this is petrified wood, in which all the cellulose fibres have been replaced by silica, even those in the bark.…

  • Altered States (film by Russell [1980])

    Drew Barrymore: …making her film debut in Altered States (1980). In 1982 she became famous for her performance as the adorable Gertie in Steven Spielberg’s blockbuster E.T.: The Extra-Terrestrial. Later that year Barrymore, at age seven, became the youngest-ever host of the television show Saturday Night Live. In 1984 she appeared in…

  • altering (sterilization)

    cat: Reproduction: …and simple operations known as spaying, neutering, or altering—has become common in affluent societies. Neutering is also viewed as an adaptive measure for indoor life.

  • Alternanthera (plant genus)

    Amaranthaceae: >Alternanthera and Iresine each have several species that are cultivated as bedding plants for their attractive and colourful leaves.

  • Alternanthera philoxeroides (plant)
  • alternate binaural loudness balance test (hearing test)

    human ear: Audiometry: …can be measured by the alternate binaural loudness balance test. The subject is asked to set the controls so that the loudness of the tone heard in the defective ear matches that of the tone heard in the normal ear. By repeating the comparison at several intensity levels, the presence…

  • alternate history (fiction)

    science fiction: Alternate histories and parallel universes: …category to parallel worlds and alternate histories. Those concepts no longer seem abstract and improbable, but they have become part of the heritage of science fiction.

  • alternate leaf arrangement (plant anatomy)

    angiosperm: Leaves: In alternate-leaved plants, the leaves are single at each node and borne along the stem alternately in an ascending spiral. In opposite-leaved plants, the leaves are paired at a node and borne opposite to each other. A plant has whorled leaves when there are three or…

  • Alternate Possibilities and Moral Responsibility (paper by Frankfurt)

    problem of moral responsibility: Contemporary compatibilism: In an influential paper, “Alternate Possibilities and Moral Responsibility” (1969), the American philosopher Harry Frankfurt questioned whether the ability to do otherwise is truly necessary for freedom. Suppose that John is on his way to a voting booth and is undecided about whether to vote for candidate A or…

  • alternating current (electronics)

    Alternating current, flow of electric charge that periodically reverses. It starts, say, from zero, grows to a maximum, decreases to zero, reverses, reaches a maximum in the opposite direction, returns again to the original value, and repeats this cycle indefinitely. The interval of time between

  • alternating electric field (physics)

    particle accelerator: Accelerating particles: …accelerate particles by using the alternating electric fields present in electromagnetic waves, typically at frequencies from 100 to 3,000 MHz—that is, ranging from radiowaves to microwaves.

  • alternating personality (psychology)

    Dissociative identity disorder, mental disorder in which two or more independent and distinct personality systems develop in the same individual. Each of these personalities may alternately inhabit the person’s conscious awareness to the exclusion of the others. In some cases all of the

  • alternating-current circuit (electronics)

    electricity: Alternating-current circuits: Certain circuits include sources of alternating electromotive forces of the sinusoidal form V = V0 cos(ωt) or V = V0 sin(ωt). The sine and cosine functions have values that vary between +1 and ?1; either of the equations for the voltage represents a…

  • alternating-current commutator motor (electrical engineering)

    electric motor: Alternating-current commutator motors: A specially designed series-commutator motor may be operated from a single-phase alternating voltage supply. When the supply current reverses, both the magnetic field and the armature current are reversed. Thus, the torque remains in the same direction. These motors are often called…

  • alternating-current generator (electrical engineering)

    Alternator, Source of direct electric current in modern vehicles for ignition, lights, fans, and other uses. The electric power is generated by an alternator mechanically coupled to the engine, with a rotor field coil supplied with current through slip rings, and a stator with a three-phase

  • alternating-current motor (electrical engineering)

    locomotive: Types of traction systems: The potential advantages of using alternating instead of direct current prompted early experiments and applications of this system. With alternating current, especially with relatively high overhead-wire voltages (10,000 volts or above), fewer substations are required, and the lighter overhead current supply wire that can be used correspondingly reduces the weight…

  • alternating-current transformer (electronics)

    Transformer, device that transfers electric energy from one alternating-current circuit to one or more other circuits, either increasing (stepping up) or reducing (stepping down) the voltage. Transformers are employed for widely varying purposes; e.g., to reduce the voltage of conventional power

  • alternating-current transmission (mechanics)

    ship: Electric drive and integrated machinery plants: Alternating-current transmission with synchronous propulsion motors also is used, usually in high-powered propulsion plants because it avoids the commutation problems that handicap high-power direct-current machinery. Exact electrical synchronization of motor speed with generator speed is required, but the mechanical speeds need not be the same.…

  • alternating-gradient focusing

    particle accelerator: Electron synchrotrons: Strong focusing was first applied to the electron synchrotron in the 1.2-GeV device built in 1954 at Cornell University in Ithaca, N.Y. All large electron synchrotrons now are equipped with linear accelerators as injectors. The practical limit on the energy of an electron synchrotron is…

  • alternation (logic)

    history of logic: The Megarians and the Stoics: They also knew “inclusive” disjunction (defined as true when at least one disjunct is true), but this was not widely used. More important, the Stoics seem to have been the first to show how some of these truth-functional words may be defined in terms of others.

  • alternation of generations (biology)

    Alternation of generations, in biology, the alternation of a sexual phase and an asexual phase in the life cycle of an organism. The two phases, or generations, are often morphologically, and sometimes chromosomally, distinct. In algae, fungi, and plants, alternation of generations is common. It is

  • Alternativa Bolivariana para las Américas (international organization)

    Bolivarian Alliance for the Peoples of Our America (ALBA), regional bloc, organized in 2004, that aims for social, political, and economic integration in Latin America and the Caribbean. ALBA, which means “dawn” in Spanish, was conceived by Venezuelan Pres. Hugo Chávez and was created by Venezuela

  • alternative (music)

    Alternative rock, pop music style, built on distorted guitars and rooted in generational discontent, that dominated and changed rock between 1991 and 1996. It burst into the mainstream when “Smells Like Teen Spirit”—the first major-label single from Nirvana, a trio based in Seattle, Washington,

  • alternative country (music genre)

    the Byrds: …progressive country aspirations inspired the alternative country movement led by Wilco and Son Volt.

  • alternative education

    Alternative education, Education that diverges in some way from that offered by conventional schools. Examples may be found in publicly funded schools, private schools, and homeschooling curricula. The focus might be on alternative structures (e.g., open classrooms), alternative subject matter

  • alternative energy

    Renewable energy, usable energy derived from replenishable sources such as the Sun (solar energy), wind (wind power), rivers (hydroelectric power), hot springs (geothermal energy), tides (tidal power), and biomass (biofuels). At the beginning of the 21st century, about 80 percent of the world’s

  • Alternative for Germany (political party, Germany)

    fascism: Later developments: …in 2017, the far-right party Alternative for Germany (Alternative für Deutschland; AfD), which had adopted an overtly anti-Islamic platform, won nearly 13 percent of the presidential vote in national elections, and by the following year it was the second most popular political party in Germany, after the Christian Democrats.

  • Alternative für Deutschland (political party, Germany)

    fascism: Later developments: …in 2017, the far-right party Alternative for Germany (Alternative für Deutschland; AfD), which had adopted an overtly anti-Islamic platform, won nearly 13 percent of the presidential vote in national elections, and by the following year it was the second most popular political party in Germany, after the Christian Democrats.

  • alternative history (fiction)

    science fiction: Alternate histories and parallel universes: …category to parallel worlds and alternate histories. Those concepts no longer seem abstract and improbable, but they have become part of the heritage of science fiction.

  • alternative hypothesis (statistics)

    statistics: Hypothesis testing: An alternative hypothesis (denoted Ha), which is the opposite of what is stated in the null hypothesis, is then defined. The hypothesis-testing procedure involves using sample data to determine whether or not H0 can be rejected. If H0 is rejected, the statistical conclusion is that the…

  • alternative minimum tax (taxation)

    Tax Reform Act of 1986: The TRA strengthened the “alternative minimum tax” provisions of the income tax code for individuals, which were first created in 1978. (The alternative minimum tax is the least that an individual or corporation must pay after all eligible exclusions, credits, and deductions have been taken.) The corporate tax rate…

  • alternative pathway (immunology)

    complement: …the classical pathway and the alternative pathway, or properdin system. A different type of signal activates each pathway. The classical pathway is triggered by groups of antibodies bound to the surfaces of a microorganism, while the alternative pathway is spurred into action by molecules embedded in the surface membranes of…

  • alternative right
  • alternative rock (music)

    Alternative rock, pop music style, built on distorted guitars and rooted in generational discontent, that dominated and changed rock between 1991 and 1996. It burst into the mainstream when “Smells Like Teen Spirit”—the first major-label single from Nirvana, a trio based in Seattle, Washington,

  • alternative school

    Alternative education, Education that diverges in some way from that offered by conventional schools. Examples may be found in publicly funded schools, private schools, and homeschooling curricula. The focus might be on alternative structures (e.g., open classrooms), alternative subject matter

  • alternative sports

    Extreme sports, sporting events or pursuits characterized by high speeds and high risk. The sports most commonly placed in this group are skateboarding, snowboarding, freestyle skiing, in-line roller-skating, street lugeing, and BMX and mountain biking. Typically, extreme sports operate outside

  • Alternative Synthetic Pathways for Pollution Prevention (United States research program)

    green chemistry: …Protection Agency (EPA) launched the Alternative Synthetic Pathways for Pollution Prevention research program under the auspices of the Pollution Prevention Act of 1990. This program marked a radical departure from previous EPA initiatives in emphasizing the reduction or elimination of the production of hazardous substances, as opposed to managing these…

  • alternative theatre (theatrical system)

    Western theatre: Alternative theatre: …in Edinburgh, a profusion of “fringe” theatres sprang up in converted cellars, warehouses, and the back rooms of pubs. Rock music, Dada, and Antonin Artaud were inspiration for groups such as the People Show, Pip Simmons Theatre Group, and Ken Campbell’s Road Show. Other companies—Foco Novo, Portable Theatre, 7:84, Belt…

  • alternative vote (political science)

    Alternative vote (AV), method of election in which voters rank candidates in order of preference. If any single candidate receives a majority of first-preference votes, that candidate is deemed elected. If no candidate clears this hurdle, the last-place candidate is eliminated and that candidate’s

  • alternative-fuel vehicle (automobile)

    automobile: Alternative-fuel vehicles: After World War II the diesel engine, particularly for light trucks and taxis, became popular in Europe because of its superior fuel economy and various tax incentives. During the 1970s General Motors converted some gasoline passenger-car engines to the more economical compression-ignition…

  • alternator (electrical engineering)

    Alternator, Source of direct electric current in modern vehicles for ignition, lights, fans, and other uses. The electric power is generated by an alternator mechanically coupled to the engine, with a rotor field coil supplied with current through slip rings, and a stator with a three-phase

  • Altertumswissenschaft (German education)

    classical scholarship: …Germans evolved the concept of Altertumswissenschaft (“science of antiquity”) to emphasize the unity of the various disciplines of which the study of the ancient world consists. Broadly speaking, the province of classical scholarship is in time the period between the 2nd millennium bc and ad 500 and in space the…

  • Altes Museum (museum, Berlin, Germany)

    Western architecture: Germany: …major work in Berlin, the Old (Altes) Museum (1823–33), is important as an early example of a national museum built in order to educate the public. With its long but undemonstrative Ionic colonnade, it is comparable to Smirke’s contemporary British Museum. Indeed, in 1826 Schinkel made an important tour of…

  • Altgeld, John Peter (governor of Illinois, United States)

    John Peter Altgeld, reformist Democratic governor of Illinois (1893–97) known principally for his pardon (June 26, 1893) of German-American anarchists involved in the Haymarket Riot, a labour protest meeting in which seven Chicago policemen were killed at Haymarket Square on May 4, 1886. Altgeld’s

  • Althaea officinalis (plant)

    Marsh mallow, (Althaea officinalis), perennial herbaceous plant of the hibiscus, or mallow, family (Malvaceae), native to eastern Europe and northern Africa. It has also become established in North America. The plant is usually found in marshy areas, chiefly near the sea. It has strongly veined

  • Althaea rosea (plant)

    Hollyhock, (Althaea rosea), herbaceous plant of the hibiscus, or mallow, family (Malvaceae), native to China but widely cultivated for its handsome flowers. The several varieties include annual, biennial, and perennial forms. The plant grows almost absolutely straight for about 1.5–2.7 metres (5–9

  • Althaea syriaca (plant, Hibiscus species)

    Rose of Sharon, (Hibiscus syriacus, or Althaea syriaca), shrub or small tree, in the hibiscus, or mallow, family (Malvaceae), native to eastern Asia but widely planted as an ornamental for its showy flowers. It can attain a height of 3 metres (10 feet) and generally assumes a low-branching

  • Althaus, Johannes (Dutch political scientist)

    Johannes Althusius, German political theorist who was the intellectual father of modern federalism and an advocate of popular sovereignty. After philosophic and legal studies in Switzerland, Althusius was a professor at the University of Herborn in Nassau until 1604, when he became syndic of the

  • Althiburos (Tunisia)

    Althiburos, ancient city of Numidia in North Africa, on the road constructed by the Roman emperor Hadrian in ad 123, between Carthage and Theveste (Tabassah) in what is now Tunisia. The town, originally an indigenous settlement, obtained municipal rights from Hadrian. Althiburos enjoyed

  • Althing (Icelandic government)

    Althing, unicameral legislature of Iceland. Founded at Thingvellir in southwestern Iceland c. 930, the Althing is one of the oldest national parliaments in the world. While things, representative assemblies of freemen, were widespread throughout medieval Scandinavia, the Althing represented the

  • Althingi (Icelandic government)

    Althing, unicameral legislature of Iceland. Founded at Thingvellir in southwestern Iceland c. 930, the Althing is one of the oldest national parliaments in the world. While things, representative assemblies of freemen, were widespread throughout medieval Scandinavia, the Althing represented the

  • althorn (musical instrument)

    Tenor horn, brass wind instrument derived from the cornet and the valved bugle, or flügelhorn. A saxhorn of tenor range and a tenor bugle are also sometimes called tenor horns. The tenor horn was used in Prussian cavalry bands by 1829. It has three valves, a cup mouthpiece, and a narrow bore and

  • Althorp, Viscount (British statesman)

    John Charles Spencer, 3rd Earl Spencer, statesman, leader of the British House of Commons and chancellor of the Exchequer from 1830 to 1834. He greatly aided Lord John Russell (afterward 1st Earl Russell), chief author of the Reform Bill of 1832, in securing its passage in the Commons. Courageous,

  • Althusius, Johannes (Dutch political scientist)

    Johannes Althusius, German political theorist who was the intellectual father of modern federalism and an advocate of popular sovereignty. After philosophic and legal studies in Switzerland, Althusius was a professor at the University of Herborn in Nassau until 1604, when he became syndic of the

  • Althusser, Louis (French scholar)

    Louis Althusser, French philosopher who attained international renown in the 1960s for his attempt to fuse Marxism and structuralism. Inducted into the French army in 1939, Althusser was captured by German troops in 1940 and spent the remainder of the war in a German prisoner of war camp. In 1948

  • Altica chalybea

    flea beetle: The grape flea beetle (Altica chalybea), 4 to 5 mm (0.16 to 0.2 inch) long and dark steel-blue in colour, eats grape buds in early spring; both the adults and larvae feed on grape leaves in the summer. They can be controlled by spraying an arsenical…

  • Altichiero (Italian painter)

    Altichiero, early Renaissance painter who was the effective founder of the Veronese school and perhaps the most significant northern Italian artist of the 14th century. Altichiero began his career in Verona, where he remained for a number of years, although nothing is known of his work from this

  • Alticinae (insect)

    Flea beetle, any member of the insect subfamily Alticinae (Halticinae) belonging to the leaf beetle family Chrysomelidae (order Coleoptera). These tiny beetles, worldwide in distribution, are usually less than 6 mm (0.25 inch) in length and dark or metallic in colour. The enlarged hindlegs are

  • Altieri Chapel (chapel, Rome, Italy)

    Gian Lorenzo Bernini: Later years: …late work is the simple Altieri Chapel in San Francesco a Ripa (c. 1674) in Rome. The relatively deep space above the altar reveals a statue representing the death of the Blessed Ludovica Albertoni. Bernini consciously separated architecture, sculpture, and painting for different roles, reversing the process that culminated in…

  • Altieri, Emilio (pope)

    Clement X, pope from 1670 to 1676. Of noble birth, Altieri was in the service of the papal embassy in Poland from 1623 to 1627, when he returned to Italy to become bishop of Camerino. Until his appointment as cardinal by Pope Clement IX in 1669, he held numerous church offices, including papal

  • altimeter (instrument)

    Altimeter, instrument that measures the altitude of the land surface or any object such as an airplane. The two main types are the pressure altimeter, or aneroid barometer, which approximates altitude above sea level by measuring atmospheric pressure, and the radio altimeter, which measures

  • Altingia (plant genus)

    sweet gum: …been ascribed to the genus Altingia, and the group was formerly placed in the family Hamamelidaceae.

  • Altingia excelsa (plant)
  • Altingia styraciflua (plant)

    sweet gum: The American sweet gum, or bilsted (Liquidambar styraciflua), which sometimes reaches 45 metres (150 feet) in moist lowlands but is usually half that height at maturity, is grown for its handsome foliage, shade, and scarlet autumnal colour. It is also valued for its heartwood, called red…

  • Altingiaceae (plant family)
  • Altiplano (region, South America)

    Altiplano, region of southeastern Peru and western Bolivia. The Altiplano originates northwest of Lake Titicaca in southern Peru and extends about 600 miles (965 km) southeast to the southwestern corner of Bolivia. It is a series of intermontane basins lying at about 12,000 feet (3,650 metres)

  • Altis (ancient site, Greece)

    Altis, in Greek religion, the sacred grove of Zeus, or the sacred precinct in Olympia, Greece. It was an irregular quadrangular area more than 200 yards (183 m) on each side, and walled except to the north, where it was bounded by the Kronion (hill of Cronus). In it were the temples of Zeus and of

  • altithermal (geology)

    global warming: Climatic variation since the last glaciation: …sometimes referred to as the Mid-Holocene Climatic Optimum. The relative warmth of average near-surface air temperatures at this time, however, is somewhat unclear. Changes in the pattern of insolation favoured warmer summers at higher latitudes in the Northern Hemisphere, but these changes also produced cooler winters in the Northern Hemisphere…

  • altitude (linear measurement)

    climate: Variation with height: There are two main levels where the atmosphere is heated—namely, at Earth’s surface and at the top of the ozone layer (about 50 km, or 30 miles, up) in the stratosphere. Radiation balance shows a net gain at these levels in most cases. Prevailing…

  • altitude above sea level (meteorology)

    barometer: …terms of atmospheric pressure or altitude above sea level. The concept of altitude above sea level, based on barometric pressure, is used to create one type of aircraft altimeter.

  • altitude sickness (medical condition)

    Altitude sickness, acute reaction to a change from sea level or other low-altitude environments to altitudes above 8,000 feet (2,400 metres). Altitude sickness was recognized as early as the 16th century. In 1878 French physiologist Paul Bert demonstrated that the symptoms of altitude sickness are

  • altitude tinting (cartography)

    map: Symbolization: Hypsographic tinting is relatively easy, particularly since photomechanical etching and other steps can be used to provide negatives for the respective elevation layers. Difficulty in the reproduction process is sometimes a deterrent to the use of treatments involving the manipulation of contours.

  • altitude, angular (coordinate)

    Altitude and azimuth, in astronomy, gunnery, navigation, and other fields, two coordinates describing the position of an object above the Earth. Altitude in this sense is expressed as angular elevation (up to 90°) above the horizon. Azimuth is the number of degrees clockwise from due north

  • altitude-azimuth mounting (astronomy)

    telescope: Reflecting telescopes: …Canary Islands, Spain, has an altitude-azimuth mounting. The significance of the latter design is that the telescope must be moved both in altitude and in azimuth as it tracks a celestial object. Equatorial mountings, by contrast, require motion in only one coordinate while tracking, since the declination coordinate is constant.…

  • Altizer, Thomas J. J. (American theologian)

    Thomas J.J. Altizer, American radical theologian associated with the Death of God movement in the 1960s and ’70s. A graduate of the University of Chicago (A.B. 1948, A.M. 1951, Ph.D. 1955), Altizer taught religion first at Wabash College (Crawfordsville, Indiana) from 1954 to 1956 and then at Emory

  • Altizer, Thomas Jonathan Jackson (American theologian)

    Thomas J.J. Altizer, American radical theologian associated with the Death of God movement in the 1960s and ’70s. A graduate of the University of Chicago (A.B. 1948, A.M. 1951, Ph.D. 1955), Altizer taught religion first at Wabash College (Crawfordsville, Indiana) from 1954 to 1956 and then at Emory

  • altjira (Australian Aboriginal mythology)

    The Dreaming, mythological period of time that had a beginning but no foreseeable end, during which the natural environment was shaped and humanized by the actions of mythic beings. Many of these beings took the form of human beings or of animals (“totemic”); some changed their forms. They were

  • altjiranga (Australian Aboriginal mythology)

    The Dreaming, mythological period of time that had a beginning but no foreseeable end, during which the natural environment was shaped and humanized by the actions of mythic beings. Many of these beings took the form of human beings or of animals (“totemic”); some changed their forms. They were

  • Altman, Benjamin (American merchant, art collector, and philanthropist)

    Benjamin Altman, American merchant, art collector, and philanthropist who established one of the world’s great department stores, B. Altman & Co. Altman had little formal schooling, but at the age of 25 he opened his first dry-goods store in Manhattan and in 1906 moved it to the uptown section,

  • Altman, Klaus (Nazi leader)

    Klaus Barbie, Nazi leader, head of the Gestapo in Lyon from 1942 to 1944, who was held responsible for the death of some 4,000 persons and the deportation of some 7,500 others. Barbie was a member of the Hitler Youth and in 1935 joined the Sicherheitsdienst (SD; “Security Service”), a special

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