Irkutsk, city and administrative centre of Irkutsk oblast (region), east-central Russia. The city lies along the Angara River at its confluence with the Irkut River. It was founded as a wintering camp in 1652, during the first Russian colonization of the area; a fort was built in 1661, and Irkutsk

Indianapolis 500: History: …owner Tony George formed the Indy Racing League (IRL) to counteract the influence of CART. The IRL has overseen the 500 since 1997. CART went bankrupt in 2003 and was re-formed the following year as Champ Car. In 2008 the IRL merged with Champ Car, unifying the two leagues under…

Salamanca: …remaining old residential college, the Colegio de Fonseca (1527–78), generally known as the Colegio de los Irlandeses because it was ceded after the Peninsular War (1808–14) to the Irish as a seminary and was so used until World War II. The faculty of law adjoins the university, and the faculty…

John Ireland was a Scottish writer, theologian, and diplomatist, whose treatise The Meroure of Wyssdome is the earliest extant example of original Scots prose. Ireland left the University of St. Andrews without taking a degree and attended the University of Paris (licentiate, 1460). He lived in

rock: Types of remanent magnetization: IRM (isothermal remanent magnetization) results from the application of a magnetic field at a constant (isothermal) temperature, often room temperature.

Billy Wilder: Films of the 1960s of Billy Wilder: …history), but Wilder’s next film, Irma La Douce (1963), was. The nonmusical adaptation of a French (and later Broadway) musical by Alexandre Breffort and Marguerite Monnot starred MacLaine and Lemmon as, respectively, a philosophical Parisian prostitute and the self-righteous constable who tries to shut down her operation. MacLaine received an…

Thuringia: History of Thuringia: …the defeat of their king, Irminfrid, at Burgscheidungen (in the present-day state of Saxony-Anhalt), on the Unstrut River, by the Frankish kings Theodoric I and Chlotar I in 531, their territory was reduced to the Harz mountains and Thuringian Forest region and was governed by Frankish dukes. In the early…

Irminger Current, branch of the warm North Atlantic Current, flowing generally westward along the south coast of Iceland. It divides into two currents west of Iceland. One proceeds northward and then eastward around Iceland, and the other flows westward and then southwestward, merging with the East

Irnerius was one of the scholars who revived Roman legal studies in Italy and the first of a long series of noted legal glossators and teachers of law (late 11th–middle 13th century) at the University of Bologna. Originally a teacher of the liberal arts, Irnerius studied law in Rome at the

International Refugee Organization, (IRO), temporary specialized agency of the United Nations that, between its formal establishment in 1946 and its termination in January 1952, assisted refugees and displaced persons in many countries of Europe and Asia who either could not return to their

Uno Chiyo: …the novel Iro zange (1935; Confessions of Love), a vivid, widely popular account of the love affairs of a male artist. The character was based on the painter Tōgō Seiji, well known in Tokyo for having attempted suicide with a lover; Uno had a five-year relationship with him after her…

Rodney Brooks: …1991 Brooks cofounded the company iRobot, which produced robots for use in the home, the military, and industry. One of its most successful models was the Roomba, a small autonomous robot introduced in 2002 that could vacuum a floor. Another iRobot product, the PackBot, was used by U.S. soldiers in…

Marshall Islands: Government and society: The Council of Iroij (Chiefs) has mainly a consultative function, concerned with traditional laws and customs.

iroko wood: iroko tree (Chlorophora excelsa), native to the west coast of Africa. It is sometimes called African, or Nigerian, teak, but the iroko is unrelated to the teak family. The wood is tough, dense, and very durable. It is often used in cabinetmaking and paneling as…

iroko wood, wood of the iroko tree (Chlorophora excelsa), native to the west coast of Africa. It is sometimes called African, or Nigerian, teak, but the iroko is unrelated to the teak family. The wood is tough, dense, and very durable. It is often used in cabinetmaking and paneling as a substitute

clothing and footwear industry: Pressing and molding processes: …major divisions: buck pressing and iron pressing. A buck press is a machine for pressing a garment or section between two contoured and heated pressure surfaces that may have steam and vacuum systems in either or both surfaces. Before 1905 all garment pressing was done by hand irons heated directly…

iron (Fe), chemical element, metal of Group 8 (VIIIb) of the periodic table, the most-used and cheapest metal. atomic number26 atomic weight55.845 melting point1,538 °C (2,800 °F) boiling point3,000 °C (5,432 °F) specific gravity7.86 (20 °C) oxidation states+2, +3, +4, +6 electron

Iron Act, (1750), in U.S. colonial history, one of the British Trade and Navigation acts; it was intended to stem the development of colonial manufacturing in competition with home industry by restricting the growth of the American iron industry to the supply of raw metals. To meet British needs,

Iron Age, final technological and cultural stage in the Stone–Bronze–Iron Age sequence. The date of the full Iron Age, in which this metal for the most part replaced bronze in implements and weapons, varied geographically, beginning in the Middle East and southeastern Europe about 1200 bce but in

ferroalloy, an alloy of iron (less than 50 percent) and one or more other metals, important as a source of various metallic elements in the production of alloy steels. The principal ferroalloys are ferromanganese, ferrochromium, ferromolybdenum, ferrotitanium, ferrovanadium, ferrosilicon,

British Steel Corporation PLC: …government-owned corporation established by the Iron and Steel Act of March 22, 1967, when the firm assumed ownership of 14 major steel companies in the United Kingdom: Colvilles Limited; Consett Iron Company Limited; Dorman, Long & Co., Limited; English Steel Corporation Limited; G.K.N. Steel Company Limited; John Summers & Sons…

pigment: Iron, or Prussian, blue and ultramarine blue are the most widely used blue pigments and are both inorganic in origin.

When new options traders get their feet wet, learn the math behind the numbers, and go through a few (or more than a few) expiration cycles, they frequently move from single- or two-leg directional plays to something a little more complex, like volatility and magnitude plays. Such trades seek to

iron processing: …carbide (Fe3C), also known as cementite, is formed; this leads to the formation of pearlite, which in a microscope can be seen to consist of alternate laths of alpha-ferrite and cementite. Cementite is harder and stronger than ferrite but is much less malleable, so that vastly differing mechanical properties are…

Mario Batali: …appearances included the cooking competition Iron Chef America, where he was one of the program’s original Iron Chefs from 2005 until his departure from the show in 2009; Spain…on the Road Again (2008), a travelogue of the titular country that featured Batali and a group of his celebrity friends; and…

Zac Efron: The Iron Claw and other projects from the 2020s: …his body, this time for The Iron Claw, portraying Kevin Von Erich, the only surviving brother in a family of professional wrestlers. Variety described his performance as “proof that some golden boys have the potential to melt themselves down and reshape themselves into something new. In this small-scale, low-budget indie,…

Iron Cross, Prussian military decoration instituted in 1813 by Frederick William III for distinguished service in the Prussian War of Liberation. Use of the decoration was revived by William I for the Franco-Prussian War of 1870, recreated in 1914 for World War I, and last revived by Adolf Hitler o

Aaron Bank: …1945 he was selected for Operation Iron Cross, an audacious mission that put Bank in command of a company of anti-Nazi German prisoners of war. Bank and his team were to parachute into the Austrian Alps, an area believed by Allied planners to be the final redoubt of Nazi leadership,…

Iron Crown of Lombardy, originally an armlet or perhaps a votive crown, as suggested by its small size, that was presented to the Cathedral of Monza, where it is preserved as a holy relic. No firm record exists of its use for coronations before that of Henry VII as Holy Roman emperor in 1312. The

Iron Curtain, the political, military, and ideological barrier erected by the Soviet Union after World War II to seal off itself and its dependent eastern and central European allies from open contact with the West and other noncommunist areas. The term Iron Curtain had been in occasional and

The Iron Curtain speech was delivered by former British prime minister Winston Churchill in Fulton, Missouri, on March 5, 1946. Churchill used the speech to emphasize the necessity for the United States and Britain to act as the guardians of peace and stability against the menace of Soviet

William Wellman: Films of the 1940s: …the average American town; and The Iron Curtain (1948) was a Cold War drama about Russian espionage in Canada. Arguably more accomplished than all three of those films was Yellow Sky (1948), an exciting western in which Gregory Peck and Richard Widmark faced off.

Iranian languages: Dialects: …Ossetic: the eastern, known as Iron, and the western, known as Digor (Digoron). Of those, Digor is the more archaic, Iron words being often a syllable shorter than their Digor counterparts—e.g., Digor madä, Iron mad “mother.” Iron is spoken by the majority of Ossetic speakers and is the basis of…

Iron Dome, short-range mobile air defense system developed for Israel by Rafael Advanced Defense Systems and Israel Aerospace Industries, with additional support from Raytheon. First deployed in 2011, Iron Dome constitutes the innermost layer of the tiered Israeli air defense network. The 2006

science fiction: Utopias and dystopias: In Norman Spinrad’s black comedy The Iron Dream (1972), a frustrated Adolf Hitler immigrates and becomes an American pulp SF novelist, to weirdly convincing effect. Whether pleasant or sinister, heavenly or apocalyptic, utopias and dystopias shared a sublime sense of ahistoricality. All solutions were necessarily final solutions, and the triumph,…

Arthur Wellesley, 1st duke of Wellington was an Irish-born commander of the British army during the Napoleonic Wars and later prime minister of Great Britain (1828–30). He first rose to military prominence in India, won successes in the Peninsular War in Spain (1808–14), and shared in the victory

William Muldoon was an American wrestling champion and boxing trainer. (Read Gene Tunney’s 1929 Britannica essay on boxing.) Muldoon was a policeman from 1876 to 1882, won the New York Police heavyweight title, and in 1880 the American Greco-Roman wrestling title. He became well known when he began

Iron Fist, American comic strip superhero created for Marvel Comics by writer Roy Thomas and artist Gil Kane. The crime-fighting martial artist first appeared in Marvel Premiere no. 15 (May 1974). Daniel Rand, who would become known as the Iron Fist, is orphaned at the age of nine when his parents

theatre: The great directors: In The Iron Flood, a play about guerrillas in the Russian Civil War, the audience was kept outside the theatre until the Red Army arrived to break open the doors and the audience flooded into the auditorium. The stage in this production was obliterated and replaced…

pen drawing: …third important ink was an iron gall, or chemical, ink. Its principal ingredients were iron sulfate, the extract of gall nuts, and a gum arabic solution. It was, in fact, the common writing ink for centuries and was employed for most early drawings. Its colour when first applied to the…

Iron Gate, the last gorge of the Ðerdap gorge system on the Danube River, dividing the Carpathian and Balkan mountains and forming part of the boundary between Serbia and Romania. It is about 2 miles (3 km) long and 530 feet (162 meters) wide, with towering rock cliffs that make it one of the most

Iron Gate: …River (including a dam and hydroelectric power plant) was completed in 1972, providing equal amounts of energy to each country and quadrupling the annual tonnage of shipping. The name Iron Gate is commonly applied to the whole 90-mile- (145-kilometer-) long gorge system.

Iron Gate: …River (including a dam and hydroelectric power plant) was completed in 1972, providing equal amounts of energy to each country and quadrupling the annual tonnage of shipping. The name Iron Gate is commonly applied to the whole 90-mile- (145-kilometer-) long gorge system.

Iron Guard, Romanian fascist organization that constituted a major social and political force between 1930 and 1941. In 1927 Corneliu Zelea Codreanu founded the Legion of the Archangel Michael, which later became known as the Legion or Legionary Movement; it was committed to the “Christian and

Lang Ping is a volleyball player and coach who was the lead spiker on the Chinese national teams that dominated women’s international volleyball in the early 1980s. Known as the “Iron Hammer,” she was revered for her elegant athleticism, fierce spiking, and tactical brilliance. Lang began playing

The Iron Heel, novel by Jack London, published in 1908, describing the fall of the United States to the cruel fascist dictatorship of the Iron Heel, a group of monopoly capitalists. Fearing the popularity of socialism, the plutocrats of the Iron Heel conspire to eliminate democracy and, with their

Lou Gehrig was one of the most durable players in American professional baseball and one of its great hitters. From June 1, 1925, to May 2, 1939, Gehrig, playing first base for the New York Yankees, appeared in 2,130 consecutive games, a record that stood until it was broken on September 6, 1995,

metaphor: For example, an iron horse—a metaphor for a train—becomes the elaborate central concept of one of Emily Dickinson’s poems, the first stanza of which is

John Ford: Early life and silent-film career: …helmer-for-hire in the production of The Iron Horse (1924), his over-budget schedule-busting epic about the construction of the transcontinental railroad in the 1860s. Ford was pressured by the studio but allowed to finish, and the film became a huge financial and critical success, placing Ford in the Olympian company of…

crystal: Ferrimagnetic materials: Two iron ions are trivalent, while one is divalent. The two trivalent ions align with opposite moments and cancel one another, so the net moment arises from the divalent iron ion. The historic lodestone that was the first magnetic material discovered was a form of magnetite.…

Robert Bly: …large as the author of Iron John: A Book About Men (1990, reprinted 2001 as Iron John: Men and Masculinity). Drawing upon Jungian psychology, myth, legend, folklore, and fairy tales (the title is taken from a story by the Brothers Grimm), the book demonstrates Bly’s masculinist convictions. Though it had…

Iron Knob, town, northeastern Eyre Peninsula, South Australia, 247 miles (397 km) northwest of Adelaide by rail. It is the centre for one of the richest deposits of iron ore in the Southern Hemisphere. Mining rights were acquired in 1897, and in 1901 the Broken Hill Proprietary Company, Ltd. (BHP),

Margaret Thatcher was a British Conservative Party politician and prime minister (1979–90), Europe’s first woman prime minister. The only British prime minister in the 20th century to win three consecutive terms and, at the time of her resignation, Britain’s longest continuously serving prime

Meryl Streep: A devil, Julia Child, and Margaret Thatcher: …role of Margaret Thatcher in The Iron Lady (2011), a portrait of the former British prime minister. For her performance, Streep earned her eighth Golden Globe Award and third Oscar. In the lighthearted Hope Springs (2012), she and Tommy Lee Jones starred as a couple trying to save their stagnant…

iron law of oligarchy, sociological thesis according to which all organizations, including those committed to democratic ideals and practices, will inevitably succumb to rule by an elite few (an oligarchy). The iron law of oligarchy contends that organizational democracy is an oxymoron. Although

subsistence theory, in labour economics, a theory of the factors that determine the level of wages in a capitalist society, according to which changes in the supply of workers constitute a basic force that drives real wages to the minimum required for subsistence (that is, for basic needs such as

Bill Hartack: …and in 1957 he rode Iron Liege to victory at the Kentucky Derby. His four other Kentucky Derby winners were Venetian Way, 1960; Decidedly, 1962; Northern Dancer, 1964; and Majestic Prince, 1969. In 1964, riding Northern Dancer, he won the Preakness for a second time and, in 1969, for a…

iron lung, mechanical medical device, sufficiently large to enclose most of an individual’s body, used to maintain respiration in persons who are unable to breathe on their own. An iron lung, the main portion of which consists of a horizontal metal cylinder, essentially acts as a mechanical

Rock and Roll Hall of Fame and Museum: List of inductees: Phil Collins, Billy Idol, Iron Maiden, Joy Division/New Order, Oasis, Sade, Wu-Tang Clan Celia Cruz, Fela Kuti, MC Lyte, Gram Parsons, Queen Latifah Linda Creed, Arif Mardin, Jimmy Miller, Rick Rubin Ed Sullivan

Black Sabbath: Success: …songs such as “Paranoid,” “Iron Man,” and “War Pigs” became metal classics. By the end of the 1970s they had sold millions of records and had become the standard by which virtually every heavy metal band had to measure itself.

Tod Browning: The MGM and Universal years: Iron Man (1931) was based on a W.R. Burnett novel and starred Lew Ayres as a prizefighter and Jean Harlow as his disloyal wife.

Iron Man, American comic book superhero, a mainstay of Marvel Comics, who first appeared in 1963 in Tales of Suspense no. 39. His creation is officially credited to four people: writer and editor Stan Lee, who plotted the first story; his brother Larry Lieber, who scripted it; artist Don Heck, who

Iron Man: From Armor Wars to the silver screen: …and Paramount released the live-action Iron Man in 2008. The film, an enormous commercial and critical success, was directed by Jon Favreau and starred Robert Downey, Jr., who proved adept at capturing Tony Stark’s personality, brilliance, and charisma. Favreau and Downey returned for the sequel Iron Man 2 (2010).

Iron Man: From Armor Wars to the silver screen: …Downey returned for the sequel Iron Man 2 (2010).

Iron Man: From Armor Wars to the silver screen: …role for The Avengers (2012), Iron Man 3 (2013), Avengers: Age of Ultron (2015), Captain America: Civil War (2016), Spider-Man: Homecoming (2017), Avengers: Infinity War (2018), and Avengers: Endgame (2019).

Vallabhbhai Patel was an Indian barrister and statesman who was one of the leaders of the Indian National Congress during the struggle for Indian independence. During the first three years of Indian independence after 1947, he served as deputy prime minister, minister of home affairs, minister of

the man in the iron mask was a political prisoner, famous in French history and legend, who died in the Bastille in 1703, during the reign of Louis XIV. There is no historical evidence that the mask was made of anything but black velvet (velours), and only afterward did legend convert its material

iron meteorite, any meteorite consisting mainly of iron, usually combined with small amounts of nickel. When such meteorites, often called irons, fall through the atmosphere, they may develop a thin, black crust of iron oxide that quickly weathers to rust. Though iron meteorites constitute only

Mike Ditka is an American gridiron football player and head coach. In the 1960s and early ’70s he proved himself one of professional football’s greatest tight ends, using his talent for catching passes to revolutionize his position. After retiring as a player, Ditka embarked on a successful

Mike Tyson is an American boxer who, at age 20, became the youngest heavyweight champion in history. His achievements in the ring, however, were often overshadowed by his turbulent personal life. (Read Gene Tunney’s 1929 Britannica essay on boxing.) A member of various street gangs at an early age,

Lake Wales: …established in 1929 on nearby Iron Mountain (295 feet [90 metres], the highest point in peninsular Florida) by Edward W. Bok, Pulitzer Prize winner (1921) and editor of the Ladies’ Home Journal. The gardens, famed for their plant and animal life, form a peaceful setting for the Bok Singing Tower,…

Iron Mountain, city, seat (1891) of Dickinson county, southwestern Upper Peninsula of Michigan, U.S., about 50 miles (80 km) west of Escanaba. Settled in 1879, it was named for its proximity to a bluff heavily stratified with iron ore. Iron Mountain was incorporated as a village in 1887 and as a

iron oxide, chemical compound that contains the elements iron and oxygen in different proportions. It is widely found on Earth, giving many soils and rocks their red, brown, and black colors. Iron oxide makes up rust, the product of corroded iron, and various forms are used as industrial pigments,

Iron Pillar of Delhi, pillar rising above the central courtyard of the Qūwat-ul-Islām mosque in the Quṭb Mīnār complex in Mehrauli, Delhi, that is famous for being relatively rust-free despite having been created more than 1,600 years ago, about 400 ce. The six-ton pillar was made during the Gupta

clothing and footwear industry: Pressing and molding processes: …major divisions: buck pressing and iron pressing. A buck press is a machine for pressing a garment or section between two contoured and heated pressure surfaces that may have steam and vacuum systems in either or both surfaces. Before 1905 all garment pressing was done by hand irons heated directly…

Frederick Charles, prince of Prussia was a prince of Prussia and a Prussian field marshal, victor in the Battle of Königgrätz (Sadowa) on July 3, 1866. The eldest son of Prince Charles of Prussia and nephew of the future German emperor William I, Frederick Charles was educated from childhood for a

iron processing, use of a smelting process to turn the ore into a form from which products can be fashioned. Included in this article also is a discussion of the mining of iron and of its preparation for smelting. Iron (Fe) is a relatively dense metal with a silvery white appearance and distinctive

putty: …substances resembling putty, such as iron putty, a mixture of ferric oxide and linseed oil; and red-lead putty, a mixture of red and white lead and linseed oil. Certain doughlike plastics are also called putty. Putty powder (tin oxide) is used in polishing glass, granite, and metal.

pyrite, a naturally occurring iron disulfide mineral. The name comes from the Greek word pyr, “fire,” because pyrite emits sparks when struck by metal. Pyrite is called fool’s gold; to the novice its colour is deceptively similar to that of a gold nugget. Nodules of pyrite have been found in

Austria: Political realignment: …itself the name of the Iron Ring. In April 1880, language ordinances were issued that made Czech and German equal languages in the “outer [public] services” in Bohemia and Moravia. In 1882 the University of Prague was divided, giving the Czechs a national university. In the same year, an electoral…

ink: …a mixture of a soluble iron salt with an extract of tannin was used as a writing ink and is the basis of modern blue-black inks. The modern inks usually contain ferrous sulfate as the iron salt with a small amount of mineral organic acid. The resulting solution is light…

hemochromatosis, inborn metabolic defect characterized by an increased absorption of iron, which accumulates in body tissues. The clinical manifestations include skin pigmentation, diabetes mellitus, enlargement of the spleen and liver, cirrhosis, heart failure, arthritis, and general weakness and

mineral deposit: Immiscible melts: Iron sulfide is the principal constituent of most immiscible magmas, and the metals scavenged by iron sulfide liquid are copper, nickel, and the platinum group. Immiscible sulfide drops can become segregated and form immiscible magma layers in a magma chamber in the same way that…

greisen: Greisen is closely connected with schorl, both in its mineralogical composition and in its mode of origin. Schorl is a pneumatolytic product consisting of quartz, tourmaline, and, often, white mica and thus passes into greisen. Both of these rocks frequently contain small percentages of cassiterite (tin oxide) and may be…

chemical compound: Binary ionic compounds: …contains Fe2+, is designated as iron(II) chloride. In each case, the Roman numeral in the name specifies the charge of the metal ion present.

chemical compound: Binary ionic compounds: …which contains Fe3+, is named iron(III) chloride. On the other hand, the compound FeCl2, which contains Fe2+, is designated as iron(II) chloride. In each case, the Roman numeral in the name specifies the charge of the metal ion present.

Olive Schreiner was a writer who produced the first great South African novel, The Story of an African Farm (1883). She had a powerful intellect, militantly feminist and liberal views on politics and society, and great vitality that was somewhat impaired by asthma and severe depressions. Her

amorphous solid: Magnetic glasses: 2 iron-boron and Fe0.8B0.1Si0.1 iron-boron-silicon. They are readily formed as long metallic glass ribbons by melt spinning or as wide sheets by planar flow casting. Ferromagnetic glasses are mechanically hard materials, but they are magnetically soft, meaning that they are easily magnetized by small magnetic fields.…

amorphous solid: Magnetic glasses: 1 iron-boron-silicon. They are readily formed as long metallic glass ribbons by melt spinning or as wide sheets by planar flow casting. Ferromagnetic glasses are mechanically hard materials, but they are magnetically soft, meaning that they are easily magnetized by small magnetic fields. Also, because of…

Ironbridge, generally considered the first cast-iron bridge, spanning the River Severn at Ironbridge, near Coalbrookdale, in Shropshire, England. It is a British national monument, and the bridge, together with the town of Ironbridge and the Ironbridge Gorge, forms the UNESCO Ironbridge Gorge World

transformer: Iron-core transformers serve analogous functions in the audio-frequency range.

stagecraft: Flying systems: …rope-set, or hemp, systems and counterweight systems. The rope-set system normally has three or more ropes attached to a metal pipe, called a batten, above the stage. The ropes pass over loft blocks on the grid above the stage. Then, at the side of the stage house, they pass over…

iron-deficiency anemia, anemia that develops due to a lack of the mineral iron, the main function of which is in the formation of hemoglobin, the blood pigment that carries oxygen from the blood to the tissues. Iron-deficiency anemia, the most common anemia, occurs when the body’s loss of iron is

mineral: Metals: The iron-group metals are isometric and have a simple cubic packed structure. Its members include pure iron, which is rarely found on the surface of Earth, and two species of nickel-iron (kamacite and taenite), which have been identified as common constituents of meteorites. Native iron has…

John Wilkinson: …Wilkinson innovation (1787) was an iron-hulled barge—a sensation at the time—to transport the heavy ordnance he was manufacturing for the government. Wilkinson taught the French how to bore cannon from solid castings; and he cast all the tubes, cylinders, and ironwork required for the Paris waterworks. Fittingly, he was buried…

amphibole: Chemical composition: …B-group cation occupancy: (1) the iron-magnesium-manganese amphibole group, (2) the calcic amphibole group, (3) the sodic-calcic amphibole group, and (4) the sodic amphibole group. The chemical formulas for selected amphiboles from each of the four compositional groups are given in the

circulatory system: Blood: …of subunits, each containing an iron–porphyrin group attached to a protein. The distribution of hemoglobins in just a few members of a phylum and in many different phyla argues that the hemoglobin type of molecule must have evolved many times with similar iron–porphyrin groups and different proteins.

spinel: …B is chromium; and the magnetite (iron-spinel) series, in which B is iron.

Ironbridge, generally considered the first cast-iron bridge, spanning the River Severn at Ironbridge, near Coalbrookdale, in Shropshire, England. It is a British national monument, and the bridge, together with the town of Ironbridge and the Ironbridge Gorge, forms the UNESCO Ironbridge Gorge World

ironclad, type of warship developed in Europe and the United States in the mid-19th century, characterized by the iron casemates that protected the hull. In the Crimean War (1853–56) the French and British successfully attacked Russian fortifications with “floating batteries,” ironclad barges