(from the article "Heliconia") These attractive plants have stout or reedlike stems. The banana-like leaves sometimes show a coppery sheen, and the midrib may be ivory and pink. One colourful species, H. psittacorum, named ...
(from the article "echinoderm") ...Ordovician about 375,000,000 years ago; stalked form with spheroidal theca; 5 well-developed food grooves.Lower Cambrian about 570,000,000 years ago; pear-shaped or spindle-shaped body with many plates arranged...
aircraft with one or more power-driven horizontal propellers or rotors that enable it to take off and land vertically, to move in any direction, or to remain stationary in the ... [21 Related Articles]
protozoan parasite genus found in insects. It is the only genus of the cnidosporidian phylum Myxozoa (Myxosporidia). The young live in the body cavity, fat, or nervous tissue of the ...
(from the article "protozoan") Certain of the tintinnid ciliates that live in the plankton of seas are programmed to break out of their cysts en masse at times of the year when the food ...
(from the article "ear, human") ...the scala tympani (tympanic ramp). The scala vestibuli and scala tympani, which are filled with perilymph, communicate with each other through an opening at the apex of the cochlea, called ...
(from the article "cave") ...growth of crystals is not interrupted, and some speleothems have shapes controlled by the forces of crystal growth rather than by the constraints of dripping and flowing water. Speleothems known ...
(from the article "grassland") ...dominated by several species of the grasses Stipa, Agropyron, Bouteloua, and Koeleria. Mixed prairie gave way in the north to a fescue prairie with Festuca and Helictotrichon; in the west, ...
a cosmological model in which the Sun is assumed to lie at or near a central point (e.g., of the solar system or of the universe) while the Earth and ... [9 Related Articles]
(from the article "Antiochus IV Epiphanes") ...Rome from 189 to 175, where he learned to admire Roman institutions and policies. His brother, King Seleucus IV, exchanged him for Demetrius, the son of Seleucus; and after Seleucus ...
(from the article "mystery religion") In the Mithraic ceremonies, there were seven degrees of initiations: Corax (Raven), Nymphus (Bridegroom), Miles (Soldier), Leo (Lion), Perses (Persian), Heliodromus (Courier of the Sun), and Pater (Father). Those in ...
freshwater protozoan of the class Zoomastigophorea. Helioflagellates sometimes are considered relatives of the heliozoans (organisms having pseudopodia but no flagella) because of their slender radiating cytoplasmic masses called pseudopodia. The ...
(from the article "military communication") Another instrument was added to the techniques for visual signaling through the development of the heliograph. It employed two adjustable mirrors so arranged that a beam of light from the ...
(from the article "photography, history of") Nicephore Niepce, an amateur inventor living near Chalon-sur-Saone, a city 189 miles (304 km) southeast of Paris, was interested in lithography, a process in which drawings are copied or drawn ...
(from the article "Dollond, John") ...Dollond learned the family trade of silk weaving. He became proficient in optics and astronomy and, in 1752, joined his eldest son, Peter, in an optical business. Two years later ...
(from the article "celestial mechanics") ...the focus S of the ellipse, the point P at which the planet is closest to the Sun is called the perihelion, and the most distant point in the orbit ...
boundary of the heliosphere, the teardrop-shaped region around the Sun that is filled with solar magnetic fields and the outward-moving solar wind consisting of protons and electrons. Nearer the Sun ... [1 Related Articles]
one of the most ancient Egyptian cities and the seat of worship of the sun god, Re. It was the capital of the 15th nome of Lower Egypt, but Heliopolis ... [3 Related Articles]
in Greek religion, the sun god. He drove a chariot daily from east to west across the sky and sailed around the northerly stream of Ocean each night in a ... [4 Related Articles]
either of two unmanned solar probes developed by West Germany in cooperation with the U.S. National Aeronautics and Space Administration (NASA). Helios 1 and Helios 2 were launched by NASA ...
(from the article "Greece") On August 14 a jetliner of the budget Cypriot carrier Helios Airways en route from Larnaca, Cyprus, to Athens and Prague crashed north of Athens, killing all 121 people on ...
(from the article "heliopause") boundary of the heliosphere, the teardrop-shaped region around the Sun that is filled with solar magnetic fields and the outward-moving solar wind consisting of protons and electrons. Nearer the Sun ...
instrument used in solar telescopes to orient and focus sunlight along a fixed direction. A typical heliostat consists of a flat plane mirror and a curved parabolic mirror. The plane ... [1 Related Articles]
any of about 250 species of tropical or temperate, mostly herbaceous plants that make up the genus Heliotropium (family Boraginaceae) and are distributed throughout the world. The genus has many ...
(from the article "Gauss, Carl Friedrich") ...in the field in charge of the observations. The project, which lasted from 1818 to 1832, encountered numerous difficulties, but it led to a number of advancements. One was Gauss's ...
any member of the protozoan class Heliozoea (superclass Actinopoda). Heliozoans are spherical and predominantly freshwater and are found either floating or stalked. They are frequently enveloped by a shell (or ... [3 Related Articles]
chemical element, inert gas of Group 0 (noble gases) of the periodic table. The second lightest element (only hydrogen is lighter), helium is a colourless, odourless, and tasteless gas that ... [47 Related Articles]
method of age determination that depends on the production of helium during the decay of the radioactive isotopes uranium-235, uranium-238, and thorium-232. Because of this decay, the helium content of ...
(from the article "cryogenics") ...K are primarily used for laboratory work, particularly research into the properties of helium. Helium liquefies at 4.2 K, becoming what is known as helium I. At 2.19 K, however, ...
(from the article "Amarillo") ...has a large copper refinery and ordnance and helicopter factories. Helium is found in large quantities in the area, and Amarillo is the site of a major helium plant; the ...
(from the article "mass spectrometry") ...and detector-are always present. L.W. Alvarez and Robert Cornog of the United States first used an accelerator as a mass spectrometer in 1939 when they employed a cyclotron to demonstrate ...
(from the article "alpha particle") positively charged particle, identical to the nucleus of the helium-4 atom, spontaneously emitted by some radioactive substances, consisting of two protons and two neutrons bound together, thus having a mass ...
(from the article "Major commercial lasers") Helium-neon lasers were the first lasers with broad commercial applications (see figure). Because they could be adjusted to generate a visible red beam instead of an infrared beam, they found ...
(from the article "Uranus") Molecular hydrogen and atomic helium are the two main constituents of the Uranian atmosphere. Hydrogen is detectable from Earth in the spectrum of sunlight scattered by the planet's clouds. The ...
(from the article "ear, human") ...canal, or acoustic meatus, is called the concha. It is partly covered by two small projections, the tonguelike tragus in front and the antitragus behind. Above the tragus a prominent ...
(from the article "electron tube") ...the electron beam, and (4) a collector with which to collect the electrons. There are two main types of TWTs, and these are differentiated by the RF structure. One uses ...
(from the article "Pauling, Linus") ...three-dimensional structure of proteins. By folding a paper on which he had drawn a chain of linked amino acids, he discovered a cylindrical coil-like configuration, later called the alpha helix. ...
(from the article "animal learning") A classic example of habituation is the following observation on the snail Helix albolabris. If the snail is moving along a wooden surface, it will immediately withdraw into its shell ...
(from the article "gastropod") ...bait. Freshwater snails rarely are eaten. Land snails of the family Helicidae have been eaten in the Middle East and Europe since prehistoric times. Today many tons of the European ...
(from the article "nebula") ...planetary nebulae are small objects, having a radius, typically, of one light-year and containing a mass of gas equivalent to about 0.3 solar mass. One of the largest known planetary ...
(from the article "gastropod") ...rarely are eaten. Land snails of the family Helicidae have been eaten in the Middle East and Europe since prehistoric times. Today many tons of the European edible snails Helix ...
(from the article "electron tube") ...interaction, and the other employs a series of staggered cavities coupled to each other for wave propagation. Each type has different characteristics and finds its use in different applications. The ...
in many religious traditions, the abode, usually beneath the earth, of the unredeemed dead or the spirits of the damned. In its archaic sense, the term hell refers to the ... [11 Related Articles]
division of rocks in North America dating to the end of the Cretaceous Period some 66 million years ago. Named for exposures studied on Hell Creek, near Jordan, Montana, it ... [1 Related Articles]
(from the article "explosive") ...was liquid and the mixture was made just prior to use. Sprengel explosives were quite popular in Europe, but consumption in the United States was relatively small except for the ...
(from the article "bridge") The Hell Gate Bridge, completed by Gustav Lindenthal in 1916, also had an aesthetic intention. It was made to look massive by its stone towers and by the increased spacing ...
(from the article "Television") Guitarist Verlaine (who took his name from the French Symbolist poet Paul Verlaine) and bassist Hell, former boarding-school roommates, formed the Neon Boys with drummer Ficca in New York City ...
(from the article "printing") Hell-Digiset carries out a preliminary analysis by inscribing the outline of each letter on a very dense grid of 3,000 to 6,000 small squares, according to the body size of ...
(from the article "Wilkes, John") A profligate by nature, Wilkes became a member of the congenial society of the "Medmenham Monks," members of the so-called Hell-Fire Club who met occasionally in the ruins of St. ...
(from the article "carboxylic acid") This reaction, called the Hell-Volhard-Zelinskii reaction, actually takes place on the acyl halide rather than on the acid itself. The purpose of the catalyst is to convert some of the ...
zoological garden in Munich. The spacious, wooded, 70-ha (173-ac) grounds resemble the animals' natural habitats. Hellabrunn specializes in breeding species threatened with extinction, such as the Przewalski's horse, and back ...
(from the article "Aegean civilizations") ...called Minoan, after the legendary King Minos of Knossos, which was the chief city of the island throughout early times. The Bronze Age of the Cyclades is known as Cycladic, ...
Norwegian pioneer of modern oceanography whose studies of the physical structure and dynamics of the oceans were instrumental in transforming oceanography from a science that was mainly descriptive to one ...
Greek historian whose work marks an advance in the development of historiography. Hellanicus lived for some time at the court of one of the kings of Macedonia and in Athens. ...
in ancient Greece, Elean officials who served as judges of the Olympic Games and who became well known for enforcing laws of fairness. They also had the honour of presenting ...
enormous impact basin in the southern hemisphere of Mars and the planet's largest recognizable impact feature. Centred at roughly 40° S, 290° W, Hellas measures about 7,000 km (4,400 miles) ... [1 Related Articles]
(Cryptobranchus alleganiensis), salamander belonging to the family Cryptobranchidae (order Caudata) found in the larger, swift-flowing streams of the Ohio River system, the Susquehanna River, and other streams in the eastern ... [1 Related Articles]
(from the article "air warfare") ...off to dive almost vertically before releasing its bombs, pulling up, and returning to the circle to dive again. In the Pacific Theatre, carrier-based dive-bombers such as the U.S. Dauntless ...
(from the article "Argonaut") The Golden Fleece had originated in the following manner. Jason's uncle Athamas had had two children, Phrixus and Helle, by his first wife, Nephele, the cloud goddess. Ino, his second ...
(from the article "Estonian literature") ...book in Estonian is a translation of the Lutheran catechism (1535). The New Testament was translated into southern Estonian in 1686 (northern Estonian, 1715); in his translation of the Bible ...
(from the article "Literature") Contemporary Denmark also proved excellent subject matter for writers. In En kvinde med hat, Inge Eriksen portrayed the experiences of a woman determined to make her mark. Helle Helle's novel ...
any member of either of two similar genera of orchids (family Orchidaceae): Cephalanthera, with about 14 north-temperate species, and Epipactis, with about 21 species native to north-temperate areas, tropical Africa, ...
(from the article "hellebore") member of either of two genera of poisonous herbaceous plants, Helleborus and Veratrum, some species of which are grown as garden ornamentals.Christmas roseLenten rose
in Greek mythology, king of Phthia (at the northern end of the Gulf of Euboea), son of Deucalion (the Greek Noah) and Pyrrha and grandson of the Titan Prometheus; he ...
(from the article "Hellen") ...of Phthia (at the northern end of the Gulf of Euboea), son of Deucalion (the Greek Noah) and Pyrrha and grandson of the Titan Prometheus; he was the eponymous ancestor ...
(from the article "Antigonid Dynasty") ...that the child's guardian, Antigonus Doson, took the throne as Antigonus III. He marched into Greece and, after defeating the Spartan king Cleomenes III at Sellasia (222), reestablished the Hellenic ...
in the eastern Mediterranean and Middle East, the period between the death of Alexander the Great in 323 BC to the conquest of Egypt by Rome in 30 BC. For ... [62 Related Articles]
adventure tale, usually with a quasi-historical setting, in which a virtuous heroine and her valiant lover are separated by a series of misadventures (e.g., jealous quarrels, kidnapping, shipwrecks, or bandits) ... [5 Related Articles]
(from the article "theatre") ...more visible and audible, while the chorus remained in the orchestra. In later times there was a high stage, with a marble frieze below and a short flight of steps ...
Belgian writer who produced more than 120 works, including novels, plays, criticism, and volumes of poetry and short stories. He also played an important role in Belgian-French literary life between ...
American writer whose novel Catch-22 (1961) was one of the most significant works of protest literature to appear after World War II. The satirical novel was a popular success, and ... [5 Related Articles]
In 2008 the Templeton Prize, with an award of £820,000 (more than $1.6 million), was conferred on Michael Heller of Poland, an ordained Roman Catholic priest and world-respected mathematical cosmologist. ...
original name William Henry Palmer British-born magician who popularized conjuring in the United States. Trained as a musician, Heller turned to magic after he saw a performance by the French ... [1 Related Articles]
(from the article "revenue sharing") ...be spent; there could be no discrimination in its use; and public audits were also required. As a result, small towns and counties, as well as large cities, received direct ...
Bohemian Jewish rabbi and scholar who is best known for his commentary on the Mishna. His works also indicate that he had extensive knowledge of mathematics, the sciences, and other ... [1 Related Articles]
(from the article "rocket and missile system") With semiactive homing the designator or illuminator might be remote from the launch platform. The U.S. Hellfire antitank missile, for example, used laser designation by an air or ground observer ...
(from the article "dobsonfly") ...on humans. Mature larvae migrate from their freshwater habitat to wet soil, moss, or decaying vegetation near the water to form pupal cells from which adults emerge. The larvae, sometimes ...
a dog represented in mythology (such as that of ancient Greece and Scandinavia) as standing guard in the underworld. In Greek mythology this was Cerberus, a three-headed, dragon-tailed dog.
(from the article "cryptology") In 1976, in one of the most inspired insights in the history of cryptology, Sun Microsystems, Inc., computer engineer Whitfield Diffie and Stanford University electrical engineer Martin Hellman realized that ...
(from the article "multiple setting") ...such locales as palaces, temples, city gates, and even ships at sea. Heaven and hell were represented by mansions at either end of the stage. The most elaborate and ingenious ...
(from the article "Yamasaki, Minoru") ...architectural firm of Smith, Hinchman and Grylls; one of his projects was a modern addition for the Neoclassic-style Federal Reserve Bank building there. He resigned in 1949 to become a ...
(from the article "pregnancy") ...minor decreases in blood platelet count, and small elevations in liver enzymes can progress quickly from a benign state to a syndrome of life-threatening proportions. This condition is known as ...
gorge of the Snake River in the United States, forming part of the Idaho-Oregon boundary, between the Seven Devils and Wallowa mountains. It has a total length of 125 miles ... [3 Related Articles]
(from the article "Hells Canyon") ...the Snake River (to help contain downstream floods in the Columbia River), the Idaho Power Company completed three dams in the area-Brownlee (1959), Oxbow (1961), and Hells Canyon (1968). The ...
(from the article "children's literature") ...a bewildering array of talented writers and artist-writers. In the field of humour and nonsense there are Ake Holmberg, with his parodic Ture Sventon detective series; the outstanding poet Lennart ...
plateau and historic corridor in North Rhine-Westphalia Land (state), western Germany. It extends east-west from Duisburg to Paderborn, parallel to the northern edge of the Sauerland, and is bounded by ...
(from the article "combinatorics") In 1912 E. Helly proved the following theorem, which has since found applications in many areas of geometry and analysis and has led to numerous generalizations, extensions and analogues known ...
(from the article "coin") ...silver, later raised to 24; but the difficulty of relating gold to silver proved insuperable, and the coinage was withdrawn. In 1344 Edward III issued his fine gold series-florin, leopard, ...
(from the article "helmet") ...Europe, early helmets were of leather reinforced with bronze or iron straps and usually took the form of conical or hemispherical skullcaps. Gradually the amount of metal increased until entire ...
(GISELE EVE SCHITTENHELM), German actress who starred in silent movies and early talkies and was best remembered for her dual performance as the innocent Maria and her counterpart, a hypersexed ...
