97 résultats pour "traveler"
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Jaguar (animal) - biology.
scientists have speculated that the jaguar’s robust canine teeth and enormously powerful bite developed specifically to pierce the armor of these reptiles. After killing a large animal, a jaguar will usually drag the carcass into dense cover before beginning to eat. If the kill is made in an open area, jaguars often drag theirprey for considerable distances. On one occasion, a jaguar killed a cow on the edge of a river and swam 790 m (2,600 ft) across the river carrying the cow. Unlike the other...
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Big Bang Theory - astronomy.
hydrogen atoms. Hydrogen atoms can only absorb and emit specific colors, or wavelengths, of light. The formation of atoms allowed many other wavelengths of light,wavelengths that had been interfering with the free electrons prior to the cooling of the universe, to travel much farther than before. This change set free radiation thatwe can detect today. After billions of years of cooling, this cosmic background radiation is at about 3 K (-270°C/-454°F).The cosmic background radiation was first d...
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Golf.
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INTRODUCTION
Golf, outdoor game in which individual players use specially designed
caddie or caddy. (Caddies, once an integral feature of the game, have now been replaced on many courses by motorized carts and pull carts.) In England the game was made popular by the attention given it by James VI of Scotland, later James I of England, and his son Charles I. In the 18th century the first golf associations were established. They included the Honourable Company of Edinburgh Golfers (founded 1744) in Edinburgh, Scotland;the Saint Andrews Society of Golfers (1754) in Saint Andrew...
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Hardware (computer).
Magnetic tape drives use magnetic tape similar to the tape used in VCR cassettes. Tape drives have a very slow read/write time, but have a very high capacity; in fact,their capacity is second only to hard disk drives. Tape drives are mainly used to back up data. Compact disc drives store information on pits burned into the surface of a disc of reflective material ( see CD-ROM). CD-ROMs can store up to 737 megabytes (MB) of data. A Compact Disc-Recordable (CD-R) or Compact Disc-ReWritable (CD-RW)...
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Herman Melville
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INTRODUCTION
Herman Melville
These lines (recited by an actor) begin the novel Moby Dick (1851), by Herman Melville.
short novel Billy Budd in manuscript form. Melville’s death in New York City on September 28, 1891, went virtually unnoticed. None of his books was still in print. VI MELVILLE’S EARLY WORKS With the exception of Mardi , all of Melville’s early books are narratives of maritime adventure based upon his own experiences and on his wide reading. Although London publisher John Murray accepted Typee for his Home and Colonial Library as a strictly factual account of South Seas travel, he was lar...
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Kuwait (country) - country.
Oil revenues have allowed Kuwait to build an extensive educational system, yielding a literacy rate of 84 percent. Public school is free and compulsory from the age of 6to 13, and several private schools also teach this age group. Kuwait University (founded in 1966) is also free and offers programs in a wide range of professional andscientific fields at several campuses. Both the extensive library system at Kuwait University and the collection at Kuwait National Museum (1957) were heavily damage...
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Helicopter.
naturally flaps down so as to increase lift. Flapping allows the differences in lift caused by uneven rotor tip speed to cancel out, producing a stable ride. Many helicoptersuse mechanical hinges with lubricated bearings, but some use flexible straps made of a composite material in order to reduce the required maintenance. Helicopters require different amounts of lift and thrust at different times during flight, because the aerodynamic forces acting on them change during hovering andacceleration...
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Radioactivity
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INTRODUCTION
Marie Curie
Working with her husband, Pierre Curie, French physicist Marie Curie discovered the radioactive elements polonium and
radium in 1898.
Rutherford when he allowed an alpha-emitting substance to decay near an evacuated thin-glass vessel. The alpha particles were able to penetrate the glass and werethen trapped in the vessel, and within a few days the presence of elemental helium was demonstrated by use of a spectroscope. Beta particles were subsequentlyshown to be electrons, and gamma rays to consist of electromagnetic radiation of the same nature as X rays but of considerably greater energy. A The Nuclear Hypothesis Rutherford...
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Fiji Islands - country.
the early 1990s. Fishing is done mainly at a subsistence level, but commercial fishing is increasing. The country also receives income from the sale of licenses to foreignvessels to fish in Fiji’s exclusive economic zone. Industry, including mining, manufacturing, and construction, employs 34 percent of Fiji’s wage earners and, in 2006, contributed 26 percent of GDP. The governmentinstituted tax-free incentives in 1988 that created a flourishing garment industry. Ready-made garments are now the...
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Observatory - astronomy.
Ultraviolet radiation, X rays, and gamma rays have shorter wavelengths than visible light has. These types of radiation tell astronomers about the hottest and mostviolent phenomena in the universe. Earth’s atmosphere blocks most of this radiation, so astronomers must send their observatories above the atmosphere aboardballoons, rockets, or satellites. Ultraviolet telescopes are much like visible light telescopes, but X-ray telescopes must have special nested cylindrical mirrors to prevent Xrays...
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Influenza.
days and disappear in seven to ten days. However, coughing and fatigue may persist for two or more weeks. Death from influenza itself is rare. But influenza can aggravate underlying medical conditions, such as heart or lung disease. Invading influenza viruses produceinflammation in the lining of the respiratory tract, damage that increases the risk that secondary infections will develop. Common complications include bronchitis,sinusitis, and bacterial pneumonia, occurring most frequently in olde...
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From Moby Dick - anthology.
'My song for ever shall recordThat terrible, that joyful hour;I give the glory to my God,His all the mercy and the power.' Nearly all joined in singing this hymn, which swelled high above the howling of the storm. A brief pause ensued; the preacher slowly turned over the leaves of theBible, and at last, folding his hand down upon the proper page, said: 'Beloved shipmates, clinch the last verse of the first chapter of Jonah—'And God had prepared agreat fish to swallow up Jonah.' 'Shipmate...
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Cell (biology) - biology.
proteins, or other proteins required by the cell. While relatively simple in construction, prokaryotic cells display extremely complex activity. They have a greater range of biochemical reactions than those found in theirlarger relatives, the eukaryotic cells. The extraordinary biochemical diversity of prokaryotic cells is manifested in the wide-ranging lifestyles of the archaebacteria andthe bacteria, whose habitats include polar ice, deserts, and hydrothermal vents—deep regions of the ocean un...
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Tennis.
and interpret rules. The head official on the court, called the chair umpire, sits on a tall chair at one end of the net. A varying number of line judges sit around the courtbeyond the path of the players. Line judges determine whether serves and shots are good or out. A net-cord judge may be employed to determine when a ball touchesthe top of the net, and a foot-fault judge may watch for that specific infraction. In the 1980s electronic devices began to be used in some professional tournaments...
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Heart.
situation. A Cardiac Cycle Although the right and left halves of the heart are separate, they both contract in unison, producing a single heartbeat. The sequence of events from the beginning ofone heartbeat to the beginning of the next is called the cardiac cycle. The cardiac cycle has two phases: diastole, when the heart’s chambers are relaxed, and systole,when the chambers contract to move blood. During the systolic phase, the atria contract first, followed by contraction of the ventricles. T...
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Christopher Columbus
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INTRODUCTION
Christopher Columbus (1451-1506), Italian-born Spanish navigator who sailed west across the Atlantic Ocean in search of a route to Asia but achieved fame by making
landfall in the Americas instead.
explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...
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Christopher Columbus.
explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...
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Christopher Columbus.
explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...
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Christopher Columbus - explorer.
explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...
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Marco Polo.
Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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Marco Polo - explorer.
Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.
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Song of the Open Road
Leaves of Grass, 1900
Walt Whitman
1
Afoot and light-hearted, I take to the open road,
Healthy, free, the world before me,
The long brown path before me, leading wherever I choose.
I think you are latent with unseen existences — you are so dear to me. You flagg'd walks of the cities! you strong curbs at the edges! You ferries! you planks and posts of wharves! you timber-lined sides! you distant ships! You rows of houses! you window-pierc'd façades! you roofs! You porches and entrances! you copings and iron guards! You windows whose transparent shells might expose so much! You doors and ascending steps! you arches! You gray stones of interminable pavements! you trodden cros...
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Cinq Semaines En Ballon
Anglais fut place de maniere a presenter le dos au lac; la voiture accomplit paisiblement son voyage
circulaire, sans qu'il songeat a se retourner une seule fois, et il revint a Londres, enchante du lac de Geneve.
chemins a la civilisation moderne; leur point d'intersection, ou nul voyageur n'a encore pu parvenir, est le ceur meme de l'Afrique. C'est la que doivent tendre tous les efforts. " " Or, les travaux de ces hardis pionniers de la science vont etre renoues par l'audacieuse tentative du docteur Samuel Fergusson, dont nos lecteurs ont souvent apprecie les belles explorations. " " Cet intrepide decouvreur (discoverer) se propose de traverser en ballon toute l'Afrique de l'est a l'ouest. Si nous somme...
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Light - astronomy.
Each different frequency or wavelength of visible light causes our eye to see a slightly different color. The longest wavelength we can see is deep red at about 700 nm.The shortest wavelength humans can detect is deep blue or violet at about 400 nm. Most light sources do not radiate monochromatic light. What we call white light,such as light from the Sun, is a mixture of all the colors in the visible spectrum, with some represented more strongly than others. Human eyes respond best to greenlight...
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THE ALCHIMIST
Pau lo C oelh o - T he A lc h em is t 2 o f 6 8 w ho l iv ed i n t h e v illa g e t h ey w ould r e ach i n a b out f o ur d ay s. H e h ad b een t o t h e v illa g e o nly o n ce, t h e y ear b efo re . T he m erc h an t w as t h e p ro prie to r o f a d ry g oods s h op, a n d h e a lw ay s d em an ded t h at t h e s h eep b e s h eare d i n h is p re se n ce, s o t h at h e w ould n ot b e c h eate d . A f r ie n d h ad t o ld t h e b oy a b out t h e s h op, a n d...
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Leonardo da Vinci
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INTRODUCTION
Leonardo da Vinci
Leonardo da Vinci was known not only as a masterful painter but as an architect, sculptor, engineer, and scientist.
and conservation program made use of the latest technology to reverse some of the damage. Although much of the original surface is gone, the majesty of thecomposition and the penetrating characterization of the figures give a fleeting vision of its vanished splendor. The Virgin of the RocksThe Virgin of the Rocks by Leonardo da Vinci was actually painted twice. The first version, done in 1485, wascommissioned to be an altarpiece but was evidently rejected. That painting now hangs in the Louvre,...
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Ship.
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INTRODUCTION
Ship, vessel that is buoyant in the water and used
B1 Biremes Experience soon proved that longer ships posed a new set of problems: They were weaker structurally, more difficult to maneuver, and presented a larger target to anyenemy ship with a ram. In the 8th century BC Mediterranean shipbuilders eliminated these problems with the bireme , a war galley built to accommodate two levels, or banks , of oarsmen. Oarsmen on the lower level rowed oars from ports cut into the side of the vessel, while those above rowed from the deck. This arrangemen...
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Laser.
their atoms into laser light. Consequently, they are the most powerful continuous wave (CW) lasers—that is, lasers that emit light continuously rather than in pulses. C Liquid Lasers The most common liquid laser media are inorganic dyes contained in glass vessels. They are pumped by intense flash lamps in a pulse mode or by a separate gas laserin the continuous wave mode. Some dye lasers are tunable, meaning that the color of the laser light they emit can be adjusted with the help of a prism lo...
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Stroke.
IV DIAGNOSIS The symptoms typical of a stroke can also be caused by other conditions, including brain tumors, various infections, and overdoses of certain drugs. A patient that hasstrokelike symptoms may undergo a battery of imaging techniques to rule out other medical problems and confirm that a stroke has occurred. The key imagingtechnique used in diagnosing strokes is computed tomography (also known as CT or CAT scanning), which employs X rays to obtain images of the internal structures oft...
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Native American Literature
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INTRODUCTION
Leslie Marmon Silko
Native American writer Leslie Marmon Silko is perhaps best known for her first novel, Ceremony (1977), a coming-of-age
story about a young man of mixed Native American and white ancestry.
SequoyahNative Americans did not use a complex written language before the immigration of Europeans to the Americas. In theearly 1820s the Cherokee leader Sequoyah developed an alphabet and written language for his native tongue. ManyCherokee learned the new written language readily, and in 1828 they published the first Native American newspaper,written in both Cherokee and English.THE BETTMANN ARCHIVE Before Native Americans came into contact with Europeans, many tribes supplemented the spoken...
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Reproductive System.
in which the young develop, and a thinner channel, the vagina, which opens exteriorly. V GENITALS In animals that lay their eggs and discharge their sperm into water, the spermatozoa reach the eggs by chemical attraction; the eggs of individuals of a species attractonly the sperm of members of the same species. When eggs and sperm are deposited at great distances from each other, the number of eggs fertilized is small. Manyamphibians and aquatic vertebrates solve this problem by attaching thems...
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Health Care System in Canada.
With a few exceptions, provincial health plans cover all medically necessary services, so that patients need not pay directly for anything except so-called incidental costs.These incidental costs include items such as a patient’s private hospital room, unless it is specified by a physician, and transportation to the hospital. Provincial healthplans also do not cover some nonessential procedures, such as laser surgery for the eye, cosmetic surgery, procedures to reverse sterilization, and, in mos...
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Astronaut - astronomy.
Every operation during a flight is important and interesting, but many might be boring to an observer. Much of an astronaut’s job is entering computer instructions,preparing samples, making measurements, recording data, fixing what breaks, and adjusting the checklist when something unexpected happens. Sometimes astronautsretrieve or repair satellites, rendezvous or dock with other spacecraft, and do important emergency repairs. The adaptability of the human crew is crucial to the successof missi...
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Arabic Literature
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INTRODUCTION
Arabic Literature, literature written in the Arabic language, from the 6th century to the present.
The life of the Prophet Muhammad also generated its own literary sources, primary among which is the hadith. The hadiths were a collection of the Prophet's sayings and actions, transmitted through a chain of authorities said to go back to Muhammad himself. The two most famous collections of hadiths are those of al-Bukhari andMuslim in the 9th century. These works provide a wealth of information covering all aspects of a Muslim's life, from prayer to personal, social, and business conduct. The...
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Native American Literature.
Many Native American writers of the 19th century wrote histories of their tribes. One tribal historian was David Cusick (Tuscarora), whose Sketches of Ancient History of the Six Nations (1827) was the first published tribal history. Tribal histories explained the deep ties that tribes had to their ancestral homelands. Beginning in the 18th century, these ties took on special meaning because the United States government began removing Native Americans from their traditional lands. These removal...
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Volcano.
before eruption. Very violent explosive eruptions are called Plinian eruptions, after Roman naturalist Pliny the Elder. These eruptions can last for several hours to daysand eject a large amount of pyroclastic material. Some volcanoes can produce much more energetic eruptions that eject materials farther from the vents because oftheir andesitic and dacitic composition. Andesitic and dacitic lava is generally thicker than basaltic lava. Stiff lava generally produces more-explosive eruptions. B No...
- The Alchimist
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Brain.
The hypothalamus lies beneath the thalamus on the midline at the base of the brain. It regulates or is involved directly in the control of many of the body's vital drivesand activities, such as eating, drinking, temperature regulation, sleep, emotional behavior, and sexual activity. It also controls the function of internal body organs bymeans of the autonomic nervous system, interacts closely with the pituitary gland, and helps coordinate activities of the brain stem. D Brain Stem The brain st...
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Cyprus - country.
40,000 cubic meters (1.4 million cubic feet) of salt water into fresh water per day, opened at Dhekelia in 1997, and a second larger plant opened at Larnaca in 2001. III PEOPLE OF CYPRUS The combined population of the Greek and Turkish sectors (2008 estimate) is 792,604. The overall population density is 86 persons per sq km (222 per sq mi). About69 percent of the island’s inhabitants live in urban areas. Greek-speaking Cypriots make up approximately 85 percent of the population. About 12 perc...
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Camping.
Commercial campgrounds serve as campsites for RV and car campers on the outskirts of national and state parks and along highways throughout North America.Owners of commercial campgrounds charge campers on a daily or weekly basis, and provide campsites equipped with hookups for electricity and water. They may alsoprovide such amenities as showers, laundry facilities, or a swimming pool. Many commercial campgrounds belong to a club or network that allows its members toreserve campsites in advance....
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Human Nutrition.
is one of the most preventable types of cancer. Nutritionists caution that most Americans need to eat more complex carbohydrates. In the typical American diet, only 40 to 50 percent of total calories come fromcarbohydrates—a lower percentage than found in most of the world. To make matters worse, half of the carbohydrate calories consumed by the typical American comefrom processed foods filled with simple sugars. Experts recommend that these foods make up no more that 10 percent of our diet, bec...
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Ant - biology.
The workers of many ant species carry a stinger within the hind end of the gaster. These ants use the stinger to defend against their enemies. In some species, workerants lack a stinger but use the tip of their gaster to squirt or dab poison at other small animals and when fighting battles with other ants, fending off predators, or killinginsects or other animals that they use as food. III PHYSIOLOGY Ants have a rigid, external skeleton called an exoskeleton that gives the soft, inner body its...
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Mexico City - geography.
The park houses some of Mexico's most important public buildings, including Chapultepec Castle. Construction of the castle began in 1783. Positioned on the park’shighest elevation, the castle functioned as a fortress during colonial times. It once served as the presidential residence and now houses the National Museum of History,which includes murals by 20th-century Mexican painter Juan O'Gorman. Los Pinos, the official residence and working offices of the president, is also on the grounds, buti...
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Baseball.
pitcher or argue a call with an umpire. Two or more coaches, positioned closer to the field, assist the manager by communicating with the players. For example,managers may decide what pitches should be thrown, when batters should swing at a pitch, and how runners should move around the bases. The manager relays thesedecisions through special hand signals that the coaches repeat to communicate to the players. Umpires are responsible for interpreting and enforcing the rules of play. They rule on t...
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Englische Literatur (Sprache & Litteratur).
Haus der Fama) und The Parlement of Foules (Das Parlament der Vögel) ist der Einfluss französischer Autoren deutlich spürbar. Chaucer diente zahlreichen Autoren des 15. Jahrhunderts in England und Schottland als Vorbild, und wirkte auf zahlreiche Künstler der Folgezeit, namentlich auf William Caxton, John Lydgate, Robert Henryson,William Dunbar und Sir David Lyndsay. In der Nachfolge Chaucers steht auch Sir Thomas Malory, der seinerseits mit Le morte Darthur (um 1460 bis 1470, Der Tod Arth...
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Astronomy - astronomy.
Telescopes may use either lenses or mirrors to gather visible light, permitting direct observation or photographic recording of distant objects. Those that use lenses arecalled refracting telescopes, since they use the property of refraction, or bending, of light ( see Optics: Reflection and Refraction ). The largest refracting telescope is the 40-in (1-m) telescope at the Yerkes Observatory in Williams Bay, Wisconsin, founded in the late 19th century. Lenses bend different colors of light by d...
- On the road