Maglemosian industry, a tool culture of northern Europe dating from the postglacial period, approximately 9000 to 5000 bc. The Maglemosian industry was named after the bog (magle mose, “big bog,” in Danish) at Mullerup, Den., where evidence of the industry was first recognized. The industry was

maglev, a floating vehicle for land transportation that is supported by either electromagnetic attraction or repulsion. Maglevs were conceptualized during the early 1900s by American professor and inventor Robert Goddard and French-born American engineer Emile Bachelet and have been in commercial

maglev, a floating vehicle for land transportation that is supported by either electromagnetic attraction or repulsion. Maglevs were conceptualized during the early 1900s by American professor and inventor Robert Goddard and French-born American engineer Emile Bachelet and have been in commercial

Bosnia and Herzegovina: Relief: …7,828 feet (2,386 metres), is Maglić, near the border with Montenegro. In the south and southwest is the Karst, a region of arid limestone plateaus that contain caves, potholes, and underground drainage. The uplands there are often bare and denuded (the result of deforestation and thin soils), but, between the…

Colombo crime family: …of cancer in 1962, and Joseph Magliocco, Profaci’s brother-in-law, took over with a tenuous grasp on power.

magma, molten or partially molten rock from which igneous rocks form. It usually consists of silicate liquid, although carbonate and sulfide melts occur as well. Magma migrates either at depth or to Earth’s surface and is ejected as lava. Suspended crystals and fragments of unmelted rock may be

oceanic crust: …are thought to represent the magma chambers, or pockets of lava, that ultimately erupt on the seafloor. The upper gabbro layer is isotropic (uniform) in structure. In some places this layer includes pods of plagiogranite, a differentiated rock richer in silica than gabbro. The lower gabbro layer has a stratified…

mineral deposit: Magmatic cumulates: …magmatic segregation are called magmatic cumulates. While a magma may start as a homogeneous liquid, magmatic segregation during crystallization can produce an assemblage of cumulates with widely differing compositions. Extreme segregation can sometimes produce monomineralic cumulates; a dramatic example occurs in the Bushveld Igneous Complex of South Africa, where cumulus…

mineral deposit: Magmatic cumulates: Magmatic segregation is a general term referring to any process by which one or more minerals become locally concentrated (segregated) during the cooling and crystallization of a magma. Rocks formed as a result of magmatic segregation are called magmatic cumulates. While a magma may start…

Reginald Aldworth Daly: …independently developed the theory of magmatic stoping, whereby molten magma rises through the Earth’s crust and shatters, but does not melt, the surrounding rocks. The rocks, being denser than the magma, then sink, making room for the magma to rise. This theory was instrumental in explaining the structure of many…

Magna Carta, charter of English liberties granted by King John on June 15, 1215, under threat of civil war and reissued, with alterations, in 1216, 1217, and 1225. By declaring the sovereign to be subject to the rule of law and documenting the liberties held by “free men,” the Magna Carta provided

JAY-Z: …name) returned in 2013 with Magna Carta Holy Grail, which, in an exclusive deal with Samsung, was made available for free to users of the company’s smartphones several days ahead of its official release. Although the album, on which the rapper reflected on his massive wealth and fame, was greeted…

Deva: …foot of the hill rises Bethlen Castle, also known as Magna Curia, built in 1621; it now houses the regional museum. Deva has little industry, but there is some food processing, and nearby are small copper and andesite mines. Pop. (2007 est.) 67,508.

Magna Graecia, group of ancient Greek cities along the coast of southern Italy; the people of this region were known to the Greeks as Italiotai and to the Romans as Graeci. The site of extensive trade and commerce, Magna Graecia was the seat of the Pythagorean and Eleatic systems of philosophy.

Great Mother of the Gods, ancient Oriental and Greco-Roman deity, known by a variety of local names; the name Cybele or Cybebe predominates in Greek and Roman literature from about the 5th century bc onward. Her full official Roman name was Mater Deum Magna Idaea (Great Idaean Mother of the Gods).

cyclothem: …have been referred to as magnacycles. These larger units are of doubtful validity and restricted utility.

Cotton Mather: His magnum opus was Magnalia Christi Americana (1702), an ecclesiastical history of America from the founding of New England to his own time. His Manuductio ad Ministerium (1726) was a handbook of advice for young graduates to the ministry: on doing good, on college love affairs, on poetry and…

Robert Burns Woodward: Scientific career: …of antibiotics: terramycin, aureomycin, and magnamycin.

Anna Magnani was an Italian actress, known for her forceful portrayals of earthy, working-class women. She won the Academy Award for best actress for her performance in The Rose Tattoo (1955). Born out of wedlock, Magnani never knew her father and was deserted by her mother, Marina Magnani. She was

Alessandro Magnasco was an Italian painter of the late Baroque period distinguished for his landscapes and genre paintings. Magnasco worked in Milan but is thought to have been influenced by the Bolognese painter Giuseppe Maria Crespi. Although Magnasco began as a portrait painter, only a

electronic game: From chess to Spacewar! to Pong: …legal obstacle posed by the Magnavox Company’s hold on the patent for video games (discussed in the next section), Atari geared up to manufacture arcade consoles in volume. It thus created the “coin-op” game industry, achieving such success that it drew competitors into its new business space, the electronic game…

Nîmes: The Tour Magne, atop a hill just outside the city, is the oldest Roman building, 92 feet (28 metres) high, but probably originally higher. Its original function is not known, but it was incorporated into the Roman wall in 16 bce.

bridge: Eugène Freyssinet: …in Philadelphia, was designed by Gustave Magnel and features three simply supported girder spans with a centre span of 48 metres (160 feet) and two end spans of 22 metres (74 feet). Although it was plain in appearance, a local art jury responsible for final approval found that the slim…

Magnentius was a usurping Roman emperor from Jan. 18, 350, to Aug. 11, 353. His career forms one episode in the struggles for imperial power that occurred after the death of Constantine the Great (ruled 306–337). Magnentius was a pagan of German descent who had achieved distinction as a soldier

Judah Leon Magnes was a rabbi, religious leader, prime founder and first president of the Hebrew University of Jerusalem, and a Zionist who came to favour a binational Arab–Jewish state. A graduate of the University of Cincinnati (A.B., 1898), Magnes attended Hebrew Union College and was ordained

Manisa, city, western Turkey. It lies in the valley of the Gediz River (ancient Hermus River), below Mount Sipylus (Manisa Dağı), 20 miles (32 km) northeast of İzmir. It was called Magnesia ad Sipylum in ancient times, and the Magnetes of Thessaly are thought to have been its first inhabitants, in

alkaline-earth metal: History: Magnesia (the name derives probably from Magnesia, a district of Thessaly in Greece), the oxide of magnesium, was shown to be an alkaline earth different from lime by the Scottish chemist Joseph Black in 1755; he observed that magnesia gave rise to a soluble sulfate,…

Magnesia ad Maeandrum, ancient inland city of Ionia, situated on a small tributary of the Maeander (Büyükmenderes) River about 12 miles southeast of Ephesus. According to Strabo, it was founded by some Thessalian Magnetes, who had collected fellow settlers from Crete en route. Accounted an Aeolian

Magnesia ad Sipylum, city in ancient Lydia, just south of the Hermus (Gediz) River. Though lying in a rich district near prehistoric regions associated with Niobe and Tantalus, and itself going back to the 5th century bc, it is of little importance except for the battle of winter 190/189 bc,

playa: Saline minerals: …are calcium carbonate (CaCO3) and magnesium carbonate (MgCO3). These form the outer “bathtub ring.” The next ring consists of sulfates of calcium and sodium (CaSO4 and Na2SO4, respectively). If sufficient calcium is present, gypsum (CaSO4·2H2O) will form. If less calcium is present, thenardite (Na2SO4) and sodium carbonate

magnesium processing: Chemical compounds: The best-known medical compounds are milk of magnesia, or magnesium hydroxide, which is used as an antacid or as a mineral supplement to maintain the body’s magnesium balance. The hydrous magnesium sulfate popularly known as Epsom salts, MgSO4·7H2O, is used as a laxative.

alkaline-earth metal: History: Magnesia (the name derives probably from Magnesia, a district of Thessaly in Greece), the oxide of magnesium, was shown to be an alkaline earth different from lime by the Scottish chemist Joseph Black in 1755; he observed that magnesia gave rise to a soluble sulfate,…

Antiochus III the Great: …was decisively defeated in the Battle of Magnesia near Mt. Sipylus, where he fought with a heterogeneous army of 70,000 men against an army of 30,000 Romans and their allies. Although he could have continued the war in the eastern provinces, he renounced all claim to his conquests in Europe…

magnesium processing: Chemical compounds: The best-known medical compounds are milk of magnesia, or magnesium hydroxide, which is used as an antacid or as a mineral supplement to maintain the body’s magnesium balance. The hydrous magnesium sulfate popularly known as Epsom salts, MgSO4·7H2O, is used as a laxative.

magnesioferrite, the mineral magnesium iron oxide, a member of the magnetite (q.v.) series of

Manisa, city, western Turkey. It lies in the valley of the Gediz River (ancient Hermus River), below Mount Sipylus (Manisa Dağı), 20 miles (32 km) northeast of İzmir. It was called Magnesia ad Sipylum in ancient times, and the Magnetes of Thessaly are thought to have been its first inhabitants, in

magnesioriebeckite, magnesium-rich variety of the silicate mineral riebeckite

magnesite, the mineral magnesium carbonate (MgCO3), a member of the calcite group of carbonate minerals that is a principal source of magnesium. The mineral has formed as an alteration product from magnesium-rich rocks or through the action of magnesium-containing solutions upon calcite. Notable

magnesium (Mg), chemical element, one of the alkaline-earth metals of Group 2 (IIa) of the periodic table, and the lightest structural metal. Its compounds are widely used in construction and medicine, and magnesium is one of the elements essential to all cellular life. atomic number 12 atomic

playa: Saline minerals: …are calcium carbonate (CaCO3) and magnesium carbonate (MgCO3). These form the outer “bathtub ring.” The next ring consists of sulfates of calcium and sodium (CaSO4 and Na2SO4, respectively). If sufficient calcium is present, gypsum (CaSO4·2H2O) will form. If less calcium is present, thenardite (Na2SO4) and sodium carbonate

magnesium processing: History: …involved the reduction of molten magnesium chloride by metallic potassium. In 1833 the English scientist Michael Faraday was the first to produce magnesium by the electrolysis of molten magnesium chloride. His experiments were repeated by the German chemist Robert Bunsen.

cordierite: Synthetic magnesium cordierite has a low thermal expansion and is used as a semirefractory material because of its resistance to thermal shock.

magnesium deficiency, condition in which magnesium is insufficient or is not utilized properly. Magnesium is a mineral that is essential to a variety of cellular metabolic reactions and sometimes has the ability to replace a portion of body calcium. It is also required for the synthesis of

olivine: Meteorites and the Earth’s mantle: Study of the olivine-like compound magnesium germanate, Mg2GeO4, showed that it has polymorphs that have both olivine and spinel structure. In the spinel structure, the oxygen atoms are arranged in cubic closest packing (in which the position of every third layer repeats that of the initial layer) instead of hexagonal…

hydride: Saline (ionic) hydrides: …of beryllium hydride, BeH2, and magnesium hydride, MgH2). These metals enter into a direct reaction with hydrogen at elevated temperatures (300–700 °C [570–1,300 °F]) to produce hydrides of the general formulas MH and MH2. Such compounds are white crystalline solids when pure but are usually gray, owing to trace impurities…

magnesium processing: Electrolysis: An insoluble magnesium hydroxide precipitates to the bottom of a settling tank, whence it is pumped as a slurry, filtered, converted to magnesium chloride by reaction with hydrochloric acid, and dried in a series of evaporation steps to 25 percent water content. Final dehydration takes place during…

alkaline-earth metal: History: Magnesia (the name derives probably from Magnesia, a district of Thessaly in Greece), the oxide of magnesium, was shown to be an alkaline earth different from lime by the Scottish chemist Joseph Black in 1755; he observed that magnesia gave rise to a soluble sulfate,…

magnesium processing, preparation of magnesium ore for use in various products. Magnesium (Mg) is a silvery white metal that is similar in appearance to aluminum but weighs one-third less. With a density of only 1.738 grams per cubic centimetre, it is the lightest structural metal known. It has a

Epsom and Ewell: …mineral springs there (from which Epsom salts were named). Stoneleigh, which was developed from farm fields and woods in the 1930s, took its name from the Stone family, which had owned the land, and from a mansion that had been located on their property.

dravite, a brown, magnesium-rich variety of tourmaline. See

magnet, any material capable of attracting iron and producing a magnetic field outside itself. By the end of the 19th century all the known elements and many compounds had been tested for magnetism, and all were found to have some magnetic property. The most common was the property of diamagnetism,

Arkansas: Resources and power: Magnet Cove, near Hot Springs in west-central Arkansas, contains dozens of minerals in one small valley, among which barite and titanium are the most important. Arkansas whetstones, made from novaculite, are regarded as among the finest in the world. Near Murfreesboro, in southwestern Arkansas, is…

particle accelerator: History: …cost of fabricating the huge magnet rings required—the largest weighs approximately 40,000 tons. A means of increasing the energy without increasing the scale of the machines was provided by a demonstration in 1952 by Livingston, Ernest D. Courant, and H.S. Snyder of the technique of alternating-gradient focusing (sometimes called strong…

neutron star: …radio transients (RRATs) and as magnetars. The RRATs are sources that emit single radio bursts but at irregular intervals ranging from four minutes to three hours. The cause of the RRAT phenomenon is unknown. Magnetars are highly magnetized neutron stars that have a magnetic field of between 1014 and 1015…

magnesium processing: Thermal reduction: This technique, utilized in the Magnetherm process, has the advantage that the liquid slag can be heated directly by electric current through a water-cooled copper electrode. The reduction reaction occurs at 1,600 °C and 400–670 pascals pressure. Vaporized magnesium is condensed in a separate system attached to the reactor, and…

paleogeography: Linear magnetic anomalies: Earth’s magnetic field has another important property. Like the Sun’s magnetic field, Earth’s magnetic field periodically “flips,” or reverses polarity—that is, the North and South poles switch places. Fluctuations, or anomalies in the intensity of the magnetic field, occur at the boundaries between…

magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion. It is the basic force responsible for such effects as the action of electric motors and the attraction of magnets for iron. Electric forces exist among stationary electric charges;

magnetic mirror: …be arranged to form a magnetic bottle that can trap charged particles in the middle.

ferrite: …single-crystal ferrites in which tiny magnetic domains called bubbles can be individually manipulated. A number of ferrites absorb microwave energy in only one direction or orientation; for this reason, they are used in microwave wave guides.

magnetic ceramics, oxide materials that exhibit a certain type of permanent magnetization called ferrimagnetism. Commercially prepared magnetic ceramics are used in a variety of permanent magnet, transformer, telecommunications, and information recording applications. This article describes the

magnetic monopole: …monopole, hypothetical particle with a magnetic charge, a property analogous to an electric charge. As implied by its name, the magnetic monopole consists of a single pole, as opposed to the dipole, which is comprised of two magnetic poles. As yet there is no evidence for the existence of magnetic…

magnetic circuit, closed path to which a magnetic field, represented as lines of magnetic flux, is confined. In contrast to an electric circuit through which electric charge flows, nothing actually flows in a magnetic circuit. In a ring-shaped electromagnet with a small air gap, the magnetic field

magnetic compass, in navigation or surveying, an instrument for determining direction on the surface of Earth by means of a magnetic pointer that aligns itself with Earth’s magnetic field. The magnetic compass is the oldest and most familiar type of compass and is used in different forms in

nuclear fusion: Magnetic confinement: In magnetic confinement the particles and energy of a hot plasma are held in place using magnetic fields. A charged particle in a magnetic field experiences a Lorentz force that is proportional to the product of the particle’s velocity and the magnetic field.…

damping: In magnetic damping, energy of motion is converted to heat by way of electric eddy currents induced in either a coil or an aluminum plate (attached to the oscillating object) that passes between the poles of a magnet.

navigation: The lodestone and the compass card: …but is now called the variation or declination. For a time, compass makers in northern countries mounted the needle askew on the card so that the fleur-de-lis indicated true north when the needle pointed to magnetic north. This practice died out about 1700 because it succeeded only for short voyages…

geomagnetic field: Representation of the field: The dip angle, I (for inclination), is the angle that the total field vector makes with respect to the horizontal plane and is positive for vectors below the plane. It is the complement of the usual polar angle of spherical coordinates. (Geographic and magnetic north coincide…

magnetic dipole, generally a tiny magnet of microscopic to subatomic dimensions, equivalent to a flow of electric charge around a loop. Electrons circulating around atomic nuclei, electrons spinning on their axes, and rotating positively charged atomic nuclei all are magnetic dipoles. The sum of

atom: Bohr’s shell model: …to the orientation of their magnetic moments. In their experiment Stern and Gerlach found only two deflections, not the continuous distribution of deflections that would have been seen if the magnetic moment had been oriented in any direction. Thus, it was determined that the magnetic moment and the angular momentum…

computer memory: Magnetic disk drives: Magnetic disks are coated with a magnetic material such as iron oxide. There are two types: hard disks made of rigid aluminum or glass, and removable diskettes made of flexible plastic. In 1956 the first magnetic hard drive (HD) was invented at…

Barkhausen effect: …the size and orientation of ferromagnetic domains, or microscopic clusters of aligned atomic magnets, that occurs during a continuous process of magnetization or demagnetization. The Barkhausen effect offered direct evidence for the existence of ferromagnetic domains, which previously had been postulated theoretically.

magnetic recording: Other magnetic recording devices.: Such magnetic recording mediums as drums and ferrite cores have been used for data storage since the early 1950s. A more recent development is the magnetic bubble memory devised in the late 1970s at Bell Telephone Laboratories.

magnetic field, a vector field in the neighbourhood of a magnet, electric current, or changing electric field, in which magnetic forces are observable. Magnetic fields such as that of Earth cause magnetic compass needles and other permanent magnets to line up in the direction of the field. Magnetic

magnetic field strength, the part of the magnetic field in a material that arises from an external current and is not intrinsic to the material itself. It is expressed as the vector H and is measured in units of amperes per metre. The definition of H is H = B/μ − M, where B is the magnetic flux

electromagnetism: Faraday’s law of induction: …found that (1) a changing magnetic field in a circuit induces an electromotive force in the circuit; and (2) the magnitude of the electromotive force equals the rate at which the flux of the magnetic field through the circuit changes. The flux is a measure of how much field penetrates…

magnetic field strength, the part of the magnetic field in a material that arises from an external current and is not intrinsic to the material itself. It is expressed as the vector H and is measured in units of amperes per metre. The definition of H is H = B/μ − M, where B is the magnetic flux

Philippe Soupault: …authored Les Champs magnétiques (1920; The Magnetic Fields), known as the first major Surrealist work. Soupault soon abandoned automatic writing to produce carefully crafted verses such as those in Westwego (1922) and Georgia (1926). As the Surrealist movement became increasingly dogmatic and political, Soupault grew dissatisfied with it and eventually…

electromagnetism: Faraday’s law of induction: …found that (1) a changing magnetic field in a circuit induces an electromotive force in the circuit; and (2) the magnitude of the electromotive force equals the rate at which the flux of the magnetic field through the circuit changes. The flux is a measure of how much field penetrates…

hysteresis: …the total magnetic field, or magnetic flux density B. The aligning process does not occur simultaneously or in step with the magnetizing field but lags behind it.

magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion. It is the basic force responsible for such effects as the action of electric motors and the attraction of magnets for iron. Electric forces exist among stationary electric charges;

amorphous solid: Magnetic glasses: The last entry in the table of technological applications of amorphous solids is an application of metallic glasses having magnetic properties. These are typically iron-rich amorphous solids with compositions such as Fe0.8B0.2 iron-boron and Fe0.8B0.1Si0.1 iron-boron-silicon. They

sound recording: The audiotape: The recording head of the tape deck consists of a tiny C-shaped magnet with its gap adjacent to the moving tape. The incoming sound wave, having been converted by a microphone into an electrical signal, produces a time-varying magnetic field in the gap of the magnet. As…

spectroscopy: Origins: …of its nucleus is called magnetic hyperfine structure. Separations between levels differing only in the relative orientation of the magnetic field of the nucleus and electron range typically from 106 hertz to 1010 hertz.

hysteresis: …the total magnetic field, or magnetic flux density B. The aligning process does not occur simultaneously or in step with the magnetizing field but lags behind it.

magnetic field strength, the part of the magnetic field in a material that arises from an external current and is not intrinsic to the material itself. It is expressed as the vector H and is measured in units of amperes per metre. The definition of H is H = B/μ − M, where B is the magnetic flux

magnetite, iron oxide mineral (FeFe2O4, or Fe3O4) that is the chief member of one of the series of the spinel (q.v.) group. Minerals in this series form black to brownish, metallic, moderately hard octahedrons and masses in igneous and metamorphic rocks and in granite pegmatites, stony meteorites,

Magnetic Island, island in the Cumberland Islands, off the coast of northeastern Queensland, Australia, in Halifax Bay, an inlet of the Coral Sea. It is one of the most easily accessible islands of the Great Barrier Reef, being only 5 miles (8 km) offshore from Townsville. Coral-fringed, wooded,

maglev, a floating vehicle for land transportation that is supported by either electromagnetic attraction or repulsion. Maglevs were conceptualized during the early 1900s by American professor and inventor Robert Goddard and French-born American engineer Emile Bachelet and have been in commercial

magnetic survey: …equal intensity to give a magnetic map of the target area that may clearly indicate the size and extent of the anomalous body.

mine: Submarine mine: The magnetic mine is triggered by the approaching ship’s magnetic field. The pressure mine employs the principle that beneath every ship in motion in shallow water there is an area of reduced pressure. The pressure mine contains a chamber divided by a diaphragm, with one side…

magnetic mirror, static magnetic field that, within a localized region, has a shape such that approaching charged particles are repelled back along their path of approach. A magnetic field is usually described as a distribution of nearly parallel nonintersecting field lines. The direction of these

atom: Bohr’s shell model: …to the orientation of their magnetic moments. In their experiment Stern and Gerlach found only two deflections, not the continuous distribution of deflections that would have been seen if the magnetic moment had been oriented in any direction. Thus, it was determined that the magnetic moment and the angular momentum…

magnetic monopole, hypothetical particle with a magnetic charge, a property analogous to an electric charge. As implied by its name, the magnetic monopole consists of a single pole, as opposed to the dipole, which is comprised of two magnetic poles. As yet there is no evidence for the existence of

termite: Nest types: …wedge-shaped mounds, called compass or magnetic mounds, that are 3 to 4 metres (9.8 to 13.1 feet) high, 2.5 metres (8.1 feet) wide, and 1 metre (3.2 feet) thick at the base. The long axis is always directed north-south, and the broad side faces east-west, an orientation that probably functions…

Sir James Clark Ross: …John Ross, he located the north magnetic pole on June 1, 1831. His own Antarctic expedition of 1839–43 was undertaken to conduct magnetic observations and to reach the south magnetic pole. Commanding the Erebus and Terror, he discovered the Ross Sea in 1841 and, while sailing toward the position assigned…

geomagnetic field: Measurement of the field: Magnetic observatories continuously measure and record Earth’s magnetic field at a number of locations. In an observatory of this sort, magnetized needles with reflecting mirrors are suspended by quartz fibres. Light beams reflected from the mirrors are imaged on a photographic negative mounted on a…

magnetic permeability, relative increase or decrease in the resultant magnetic field inside a material compared with the magnetizing field in which the given material is located; or the property of a material that is equal to the magnetic flux density B established within the material by a

surface coating: Specialty, functional, and other pigments: Magnetic pigments, such as acicular iron oxide and chromium oxide pigments, are used in magnetic audio and video tapes for information storage.

magnetism: Fundamentals: …depends on the degree of magnetization of the matter in the field. Magnetization depends on the size of the dipole moments of the atoms in a substance and the degree to which the dipole moments are aligned with respect to each other. Certain materials, such as iron, exhibit very strong…

magnetic pole, region at each end of a magnet where the external magnetic field is strongest. A bar magnet suspended in Earth’s magnetic field orients itself in a north–south direction. The north-seeking pole of such a magnet, or any similar pole, is called a north magnetic pole. The south-seeking