Sevilla: History: The Silingi Vandals made it the seat of their kingdom early in the 5th century ce, but in 461 it passed under Visigothic rule. In 711 the town fell to the Muslims, and under their rule Ixvillia, as it was then called, flourished. It became a…

silique, any dry fruit that separates at maturity into two or four segments called valves, leaving a persistent partition that bears the seeds. The valves remain connected at the top. A typical silique is an elongated capsule, such as in cabbage. A silicle, or silicula, is a short and broad

katydid: Physical characteristics: Siliquofera grandis, for example, which is among the largest of the katydids, has a wingspan of more than 25 cm (9.8 inches). Other species, however, including some common ones, have short wings or are nearly wingless. As a group, katydids are poor flyers. Many species…

Savai‘i: …6,095 feet (1,858 meters) at Mount Silisili, its highest point. A string of volcanic craters extends from the east coast at Tuasivi to Samoa’s westernmost point at Cape Mulinu‘u. Eruptions in the early 1900s ruined many plantations on Savai‘i, but the volcanoes have been quiescent since 1911.

Silistra, town, extreme northeastern Bulgaria, on the Danube River opposite Romania. To the south and southeast are the remains of the old fortifications. The Romans founded a fortified camp at Durostorum in the early 2nd century ad. The medieval town that sprang from it, known as Drastar, stood

Silius Italicus was a Latin epic poet whose 17-book, 12,000-line Punica on the Second Punic War (218–201 bc) is the longest poem in Latin literature. Silius was a distinguished advocate in his earlier years. He later took to public service and was a consul in 68, the year of Nero’s death. His

Claudius: Administrative innovations of Claudius: …marriage ceremony with her lover, Gaius Silius. Messalina and Silius were killed, and Claudius married his niece Agrippina, an act contrary to Roman law, which he therefore changed. To satisfy Agrippina’s lust for power, Claudius had to adopt her son Lucius Domitius Ahenobarbus (later the emperor Nero), to the disadvantage…

Siliana, town in northern Tunisia located on the western edge of the Dorsale Mountains. The town is built not far from Maktar (Makthar), an ancient site with megalithic monuments, Numidian ruins, and Roman remains. Lying in a fertile region dominated by the Dorsale Mountains, which extend from the

Lake Siljan, lake in the administrative län (county) of Dalarna, central Sweden. Covering an area of 112 square miles (290 square km; including Orsa and In lakes, 137 square miles [354 square km]), it is Dalarna’s largest lake. After receiving the Österdal River at Mora, the lake stretches for a

Devonian extinctions: The Siljan structure in Sweden, an impact crater about 65 km (about 40 miles) in diameter, has been dated to approximately 377 million years ago. This places the impact within the error range for the estimated boundary between the Frasnian-Famennian stages and also within the Kellwasser…

Lake Siljan, lake in the administrative län (county) of Dalarna, central Sweden. Covering an area of 112 square miles (290 square km; including Orsa and In lakes, 137 square miles [354 square km]), it is Dalarna’s largest lake. After receiving the Österdal River at Mora, the lake stretches for a

silk, animal fibre produced by certain insects and arachnids as building material for cocoons and webs, some of which can be used to make fine fabrics. In commercial use, silk is almost entirely limited to filaments from the cocoons of domesticated silkworms (caterpillars of several moth species

sapphire: …faint whitish sheen, known as silk. Tiny, regularly arranged mineral inclusions (commonly rutile) and elongate cavities are responsible for the asterism shown by star sapphire.

kapok: Physical description: The kapok is deciduous, dropping its foliage after seasonal rainy periods. Flowering occurs when the tree is leafless, thereby improving access for the bats that feed on the sugar-laden nectar of kapok blossoms. In doing so, the bats unwittingly pollinate the tree’s flowers. The flowers open…

kapok: Physical description: The kapok is deciduous, dropping its foliage after seasonal rainy periods. Flowering occurs when the tree is leafless, thereby improving access for the bats that feed on the sugar-laden nectar of kapok blossoms. In doing so, the bats unwittingly pollinate the tree’s flowers. The flowers open…

silk floss tree, (Ceiba speciosa), thorny flowering tree of the mallow family (Malvaceae), native to South America but cultivated as an ornamental in other regions. The seeds yield a vegetable silk used in upholstery. It was formerly called Chorisia speciosa. The silk floss tree is a large

spider: Silk: …have only two types of silk glands, but orb weavers have at least seven, each of which produces a different kind of silk; e.g., aciniform glands produce silk for wrapping prey, ampullate glands produce the draglines and frame threads, and cylindrical glands produce parts of the egg sac. Epigastric silk…

silky oak, (Grevillea robusta), large tree native to Australia and also grown as a street tree in warm areas and, in its juvenile stage, as an indoor pot plant. It belongs to the family Proteaceae (see Proteales). In Australia it is cut for timber, but elsewhere it is valued for its graceful,

albizia, (genus Albizia), genus of trees or shrubs in the pea family (Fabaceae). The genus is pantropical, though most species are native to warm regions of the Old World. The plants are widely used for fodder and timber, and many are important in traditional medicine. Several species are grown as

Silk Road, online black market known for providing a platform to buy and sell illegal drugs and for hosting other illicit activities. The site was founded by Ross Ulbricht in February 2011 and eventually shut down by law enforcement in 2013. Silk Road was the first modern darknet market and was

Silk Road, ancient trade route, linking China with the West, that carried goods and ideas between the two great civilizations of Rome and China. Silk went westward, and wools, gold, and silver went east. China also received Nestorian Christianity and Buddhism (from India) via the Silk Road.

Mark Morris: later collaborated with Yo-Yo Ma’s Silk Road Ensemble on Layla and Majnun (2016), a stage production of an Azerbaijani opera based on an ancient Arabic folktale. During the height of the COVID-19 pandemic in 2020–21, Morris choreographed short video dances for his company and a piece intended to be performed…

Mark Morris: later collaborated with Yo-Yo Ma’s Silk Road Ensemble on Layla and Majnun (2016), a stage production of an Azerbaijani opera based on an ancient Arabic folktale. During the height of the COVID-19 pandemic in 2020–21, Morris choreographed short video dances for his company and a piece intended to be performed…

Silk Road, ancient trade route, linking China with the West, that carried goods and ideas between the two great civilizations of Rome and China. Silk went westward, and wools, gold, and silver went east. China also received Nestorian Christianity and Buddhism (from India) via the Silk Road.

silkscreen, sophisticated stenciling technique for surface printing, in which a design is cut out of paper or another thin, strong material and then printed by rubbing, rolling, or spraying paint or ink through the cut out areas. It was developed about 1900 and originally used in advertising and

Robert Rauschenberg: …borrowed from Andy Warhol the silk-screen stencil technique for applying photographic images to large expanses of canvas, reinforcing the images and unifying them compositionally with broad strokes of paint reminiscent of Abstract Expressionist brushwork. These works draw on themes from modern American history and popular culture and are notable for…

Bruno Mars: Silk Sonic and other releases and collaborations: Paak to form Silk Sonic, and in 2021 they released the album An Evening with Silk Sonic. It featured a number of popular singles, including “Leave the Door Open,” which received Grammys for best record and song, among other awards.

silk spider, (genus Nephila), any of a genus of the class Arachnida (phylum Arthropoda), so named because of the great strength of their silk and the golden colour of their huge orb webs. These webs often measure 1 metre (about 3.3 feet) or more in diameter and are suspended between trees by guy

Cole Porter: …the Shrew), Can-Can (1953), and Silk Stockings (1955). He concurrently worked on a number of motion pictures.

Fred Astaire: Later musicals: Easter Parade, Royal Wedding, and The Band Wagon: …classic MGM musicals ended with Silk Stockings (1957), after which his screen appearances were mostly in nondancing character roles. He continued to dance with new partner Barrie Chase for several Emmy Award-winning television specials throughout the 1950s and ’60s, and he danced again on-screen in Finian’s Rainbow (1968) and for…

textile: Sewing thread: Silk thread has great elasticity and strength combined with fine diameter. It can be permanently stretched in sewing, and is suitable for silks and wools. Buttonhole twist is a strong, lustrous silk about three times the diameter of normal sewing silk, and is used for…

albizia: Silk tree, or powderpuff tree (Albizia julibrissin), native to Asia and the Middle East, grows to about 9 metres (30 feet) tall, has a broad spreading crown, and bears flat pods about 12 cm (5 inches) long. Indian albizia, or siris (A. lebbek), native to…

albizia, (genus Albizia), genus of trees or shrubs in the pea family (Fabaceae). The genus is pantropical, though most species are native to warm regions of the Old World. The plants are widely used for fodder and timber, and many are important in traditional medicine. Several species are grown as

Shilka River, river, Chita oblast (province), southeastern Russia, formed by the union of the Onon and Ingoda rivers. It flows 348 miles (560 km) northeast to unite with the Argun to form the Amur River on the Russia–China border. The area of its drainage basin is 80,000 square miles (206,000

Silkeborg, city, eastern Jutland, Denmark, on the Gudenå River and Langsø, a small lake, west of Århus. An episcopal town of some importance in the Middle Ages, its castle became a royal hunting and fishing base after the Reformation. The present city, dating from 1845 (chartered 1900), grew up

silken fungus beetle, (family Cryptophagidae), any of approximately 800 insect species (insect order Coleoptera) in which the adult beetles are less than 5 mm (15 inch) in length, are oval, are yellow or brown, and are covered with fine, silky hairs. These beetles usually feed on fungi and decaying

Thomas Fitzgerald, 10th earl of Kildare was the leader of a major Irish rebellion against King Henry VIII of England. The failure of the uprising ended the Fitzgerald family’s hereditary viceroyalty of Ireland and led to the tightening of English control over the country. When his father, the Irish

Leslie Marmon Silko is an American poet and novelist whose work often centers on the dissonance between Native and white cultures. Her best-known work is the novel Ceremony (1977), which is considered a seminal work of Native literature. (Read Britannica’s essay “13 Great Indigenous Writers to Read

Osvaldo Golijov: …Time, a recording by the Silkroad Ensemble. The song cycle was based on David Grossman’s 2011 novel about a father’s grief for his deceased son.

silkscreen, sophisticated stenciling technique for surface printing, in which a design is cut out of paper or another thin, strong material and then printed by rubbing, rolling, or spraying paint or ink through the cut out areas. It was developed about 1900 and originally used in advertising and

Nora Ephron: …Alice Arlen, the screenplay for Silkwood (1983), based on the true story of Karen Silkwood (portrayed in the movie by Meryl Streep), a union activist who died while investigating safety violations at a nuclear fuel production plant. Silkwood won Ephron her first Academy Award nomination for best original screenplay. She…

Karen Silkwood was an American laboratory technician and activist who attempted to expose the safety violations and negligence at Kerr-McGee’s Cimarron River nuclear facility. The circumstances of her death brought attention to bear on the dangers and wide-ranging and previously little-known

silkworm moth, (Bombyx mori), lepidopteran whose caterpillar has been used in silk production (sericulture) for thousands of years. Although native to China, the silkworm has been introduced throughout the world and has undergone complete domestication, with the species no longer being found in the

anteater: The silky anteater: Also known as the two-toed, pygmy, or dwarf anteater, the silky anteater (Cyclopes didactylus) is the smallest and least-known member of the family. The silky anteater is found from southern Mexico southward to Bolivia and Brazil. It is not rare but is difficult…

stewartia: Silky camellia, or Virginia stewartia (S. malacodendron), a shrub up to 3.5 metres (11.5 feet) high, has white flowers with purple stamens. Another American species is the mountain stewartia, sometimes called mountain camellia (S. ovata), which is also shrubby; it is mostly confined to the…

silky flycatcher, (family Ptilogonatidae), any of four arboreal bird species found in dry, brushy regions from Nevada south to Panama that have silky feathers, prominent crests, and broad bills. They are about 19 cm (7.5 inches) long. Their basic diet consists of mistletoe berries, supplemented

neuropteran: Annotated classification: Family Psychopsidae (silky lacewings) Adults large mothlike species; antennae short, wings broad. Larvae elongated, flat; head broad posteriorly, closely attached to prothorax; jaws incurved, large, sicklelike; often arboreal, under bark. Family Osmylidae (osmylidflies) Adults medium to large; head wider than long; antennae filiform, short; 3

mineral: Lustre: …milky quartz may exhibit this); silky, descriptive of the lustre of a skein of silk or a piece of satin and characteristic of some minerals in fibrous aggregates (examples are fibrous gypsum [CaSO4 ∙ 2H2O], known as satin spar, and chrysotile asbestos [Mg3Si2O5(OH)4]); and adamantine, having the

silky oak, (Grevillea robusta), large tree native to Australia and also grown as a street tree in warm areas and, in its juvenile stage, as an indoor pot plant. It belongs to the family Proteaceae (see Proteales). In Australia it is cut for timber, but elsewhere it is valued for its graceful,

willow: … fastigiata) is a variety especially common at Xochimilco near Mexico City.

pocket mouse: Natural history: The nine species of silky pocket mice (genus Perognathus) are very small, weighing from 5 to 30 grams (0.2 to 1.1 ounces) and having a body length of 6 to 9 cm (2.4 to 3.5 inches) and hairy tails 5 to 10 cm long. Silky pocket mice have soft…

silky terrier, Australian breed of toy dog, first shown in 1907. It originated in Sydney and was once known as the Sydney silky. A rather low-set dog, the silky terrier stands 9 to 10 inches (23 to 25.5 cm) and weighs 8 to 10 pounds (3.5 to 4.5 kg). Its silky, fine coat is glossy blue-gray and tan,

sill, flat intrusion of igneous rock that forms between preexisting layers of rock. Sills occur in parallel to the bedding of the other rocks that enclose them, and, though they may have vertical to horizontal orientations, nearly horizontal sills are the most common. Sills may measure a fraction

Anna Peck Sill was an American educator who opened and administered a girls’ school that would become Rockford College. Sill began teaching school at the age of 20, and in 1843 she opened a seminary in Warsaw, New York. From 1846 to 1849 she headed the female department of the Cary Collegiate

Silla, one of the three kingdoms of ancient Korea and the one that in 668 unified Korea under the Unified Silla dynasty (668–935). Silla is traditionally believed to have been founded by Hyeokgeose in 57 bce. By the 2nd century ce, a distinct confederation of local tribes was definitely in

Monterrey: …against the scenic backdrop of Mount Silla, which rises above the plain to an elevation of more than 5,500 feet (1,700 metres). Pop. (2010) 1,135,512; metro. area, 4,089,962; (2020) 1,142,952; metro. area, 5,341,177.

perciform: Annotated classification: Family Sillaginidae (whitings) Oligocene to present. Elongated fishes with long, conical snout, small mouth; moderately long dorsal and anal fins; anal fin with 2 weak spines. About 31 species of small marine fishes of shallow water; Indo-Pacific, often in estuaries and river mouths; dig in bottom…

Frans Eemil Sillanpää was the first Finnish writer to win the Nobel Prize for Literature (1939). The son of a peasant farmer, Sillanpää began studying natural science but in 1913 returned to the country, married, and began to write. His first short stories were published in journals in 1915. From

African literature: Ethiopian: Heruy Walda Sellasse, an Ethiopian foreign minister who became the country’s first major writer, wrote two novels that are critical of child marriage and that extol Christianity and Western technology. But he was also critical of the Christian church and proposed in one of his…

Žilina, town, north-central Slovakia. It lies along the Váh River at its confluence with the Kysuca and Rajčianka rivers. Originally an early 13th-century Slavic trading settlement, Žilina became a free royal town in 1312. It has an arcaded marketplace and medieval buildings, including the

Larsa: …12th king of the dynasty, Silli-Adad (c. 1835), reigned for only a year and was then deposed by a powerful Elamite, Kutur-Mabuk, who installed his son Warad-Sin (1834–23) as king. This act apparently caused little disruption in the economic life of Larsa, and this was in fact a most prosperous…

Dumaguete: Silliman University, an American Presbyterian missionary school with a well-known liberal arts college, was founded there in 1901. Its presence has resulted in a considerable degree of Americanization. This university and the Foundation College (1949) attract students from various sectors of the archipelago, particularly the…

Benjamin Silliman: …and chemist who founded the American Journal of Science and wielded a powerful influence in the development of science in the United States.

Benjamin Silliman was a geologist and chemist who founded the American Journal of Science and wielded a powerful influence in the development of science in the United States. Silliman was appointed professor of chemistry and natural history at Yale, from which he had graduated in 1796. He was

Benjamin Silliman was an American chemist whose report on the potential uses of crude-oil products gave impetus to plans for drilling the first producing oil well, near Titusville, Pa. The son of the noted geologist and chemist Benjamin Silliman (1779–1864), he assisted his father in setting up a

sillimanite, brown, pale green, or white glassy silicate mineral that often occurs in long, slender, needlelike crystals frequently found in fibrous aggregates. An aluminum silicate, Al2OSiO4, it occurs in high-temperature regionally metamorphosed clay-rich rocks (e.g., schists and gneisses).

Alan Sillitoe was a writer, one of the so-called Angry Young Men, whose brash and angry accounts of working-class life injected new vigour into post-World War II British fiction. The son of a tannery worker, Sillitoe worked in factories from the age of 14. In 1946 he joined the air force, and for

calligraphy: The scripts of humanism (14th to 16th century): …men compiled their researches into sillogi (anthologies of texts from Roman inscriptions) that provided models for square capital letters.

Beverly Sills was an American operatic soprano who won international fame many years before her Metropolitan Opera debut at age 46. After retirement from her singing career, she became a notable arts advocate and fundraiser. Sills was early destined by her mother for a career in the performing

David L. Sills was an American sociologist known for his studies of organizational goals in voluntary associations. Sills received a Ph.D. from Columbia University (1956). He served as a research analyst in the public opinion and sociological research division during the Allied occupation of Japan

David L. Sills was an American sociologist known for his studies of organizational goals in voluntary associations. Sills received a Ph.D. from Columbia University (1956). He served as a research analyst in the public opinion and sociological research division during the Allied occupation of Japan

mechanics of solids: The substance called Silly Putty (trademark), a polymerized silicone gel familiar to many children, is another example. If a ball of it is left to sit on a table at room temperature, it flows and flattens on a time scale of a few minutes to an hour. But…

Walt Disney: First animated cartoons: …started a new series called Silly Symphonies with a picture entitled The Skeleton Dance, in which a skeleton rises from the graveyard and does a grotesque, clattering dance set to music based on classical themes. Original and briskly syncopated, the film ensured popular acclaim for the series, but, with costs…

Naftali Bennett: Prime ministership: The coalition’s chairwoman, Idit Silman, joined the opposition after the left-wing health minister upheld a court ruling that permitted the entrance of leavened foodstuffs (chametz) into hospitals during Passover, a Jewish holiday in which leaven is prohibited. Her statement cited frustration with the unity government and her desire…

J.R.R. Tolkien: The Hobbit and The Lord of the Rings: …this “legendarium,” which eventually became The Silmarillion, partly to provide a setting in which “Elvish” languages he had invented could exist. But his tales of Arda and Middle-earth also grew from a desire to tell stories, influenced by a love of myths and legends. To entertain his four children, he…

silo, in agriculture, airtight structure that encloses and protects silage (q.v.; partially fermented fodder, called haylage if made from grass), keeping it in the succulent and slightly sour condition edible for farm animals. A common type silo is an upright cylindrical tower 10 to 18 feet (3 to 5

Rebecca Ferguson: Dune and later credits: …in the Apple TV+ series Silo (2023– ). The sci-fi drama was based on Hugh Howey’s dystopian books about people who live in an underground bunker and know little about the outside world.

fortification: Nuclear fortification: …these works was the missile silo, a tubular structure of heavily reinforced concrete sunk into the ground to serve as a protective installation and launch facility for a single intercontinental ballistic missile (ICBM). These silos were “hardened” to resist a calculated amount of blast and shock from a nuclear detonation.…

Diego de Siloé was a sculptor and architect whose achievements are recognized as among the finest of the Spanish Renaissance. His sculpture is considered the high point of the Burgos Plateresque; his Granada Cathedral is considered the finest of all Plateresque buildings and one of the most

Gil de Siloé was recognized as the greatest Spanish sculptor of the 15th century. His origins are still a matter of dispute. The many names by which Gil is known are evidence of the confusion surrounding his origin. Urliones, or Urlienes, probably refers to Orléans, and Emberres, or Amberes,

Gil de Siloé was recognized as the greatest Spanish sculptor of the 15th century. His origins are still a matter of dispute. The many names by which Gil is known are evidence of the confusion surrounding his origin. Urliones, or Urlienes, probably refers to Orléans, and Emberres, or Amberes,

Ignazio Silone was an Italian novelist, short-story writer, and political leader, world famous during World War II for his powerful anti-Fascist novels. Born into a rural family, Silone was educated in the town of his birth until he was 15, when an earthquake killed his mother and left the family

silicone, any of a diverse class of fluids, resins, or elastomers based on polymerized siloxanes, substances whose molecules consist of chains made of alternating silicon and oxygen atoms. Their chemical inertness, resistance to water and oxidation, and stability at both high and low temperatures

North Indian temple architecture: …of temple mentioned in the Shilpa-shastras (traditional canons of architecture), but exact correlation of the Shilpa-shastra terms with extant architecture has not yet been established.

Thailand: Cultural institutions: …of branches throughout the country), Silpakorn University, and the National Theatre. Silpakorn University, located in Bangkok, provides training in all of the Thai fine arts, including drama and music. Its faculty members also design buildings for the government and for religious institutions in styles that preserve traditional Thai architectural forms.…

carrion beetle, (family Silphidae), any of a group of beetles (insect order Coleoptera), most of which feed on the bodies of dead and decaying animals, thus playing a major role as decomposers. A few live in beehives as scavengers, and some eyeless ones live in caves and feed on bat droppings.

cooking: Ancient Rome: …a wild giant fennel (silphium), which the Romans loved so much that they ate the plant to extinction. Laser not only was a versatile culinary ingredient but was used for medicinal purposes as well (primarily as a digestive aid); it may have also been perceived as a contraceptive. As…

Silphium, genus of tall perennial plants in the family Asteraceae, consisting of about 23 yellow-flowered species commonly called rosinweed, native to North America. Many species have rough leaves that may be opposite each other, alternate along the stem, or be grouped in whorls. The base of each

Silphium: Compass plant, or pilotweed (S. laciniatum), is a prairie plant with large, deeply cut, lance-shaped leaves. It may grow to 3.5 metres (about 12 feet) and has a tall flower stalk with solitary large flowers.

Silphium: The base of each oval cup-plant (Silphium perfoliatum) leaf surrounds the square stem and may hold water. Compass plant, or pilotweed (S. laciniatum), is a prairie plant with large, deeply cut, lance-shaped leaves. It may grow to 3.5 metres (about 12 feet) and has a tall flower stalk with solitary…

Frank Lloyd Wright: The early Chicago years: …where he found employment with J.L. Silsbee, doing architectural detailing. Silsbee, a magnificent sketcher, inspired Wright to achieve a mastery of ductile line and telling accent. In time Wright found more rewarding work in the important architectural firm of Dankmar Adler and Louis Sullivan. Wright soon became chief assistant to…

Yash Chopra: Early life and family: …such as Kabhi Kabhie and Silsila (1981; “The Affair”). Their elder son, Aditya Chopra, is regarded as one of the most influential of contemporary Bollywood producers, and their younger son, Uday, is an actor and producer. Aditya Chopra is married to Rani Mukerji, an acclaimed Bollywood actress.

silt, sediment particles ranging from 0.004 to 0.06 mm (0.00016 to 0.0024 inch) in diameter irrespective of mineral type. Silt is easily transported by moving currents but settles in still water. It constitutes about 60 percent of the material in the Mississippi River delta. An unconsolidated

siltstone, hardened sedimentary rock that is composed primarily of angular silt-sized particles (0.0039 to 0.063 mm [0.00015 to 0.0025 inch] in diameter) and is not laminated or easily split into thin layers. Siltstones, which are hard and durable, occur in thin layers rarely thick enough to be

Buddhism: Yogachara/Vijnanavada (Faxiang/Hossō): … provided the foundation for the Silun school. Silun was succeeded as the major vehicle of Yogachara thought in China by the Faxiang school, which was founded by Xuanzang, the 7th-century Chinese pilgrim-translator, and his main disciple, Kuiji. Xuanzang went to India, where he studied the works of Dharmapala (died 561)…

Silures, a powerful people of ancient Britain, occupying much of southeastern Wales. Incited by the king of the Trinovantes tribe, Caratacus, they fiercely resisted the Roman conquest from about ad 48. A Roman legionary fortress was established first at Glevum (Gloucester) and later at Isca

Sir Roderick Impey Murchison: …successive editions of his work Siluria (1854; 5th ed. 1872), which presented the main features of the original Silurian System together with information on new findings. In addition, he fought unsuccessfully against the splitting of his original Silurian System into three parts: the Cambrian Period (about 542 million to 488…

Silurian Period, in geologic time, the third period of the Paleozoic Era. It began 443.8 million years ago and ended 419.2 million years ago, extending from the close of the Ordovician Period to the beginning of the Devonian Period. During the Silurian, continental elevations were generally much

Down: The basic geology is Silurian, with much slate and sandstone. The climate is temperate, rainfall varying from 65 inches (1,650 mm) a year in the Mournes to less than 35 inches in the east and north. Although soils of the southern slopes in the north are very fertile, a…

Sir Roderick Impey Murchison: …embodied in the monumental work The Silurian System (1839). Following the establishment of the Silurian System, Murchison and Sedgwick founded the Devonian System, based on their research of the geology of southwestern England and the Rhineland. Murchison then went on an expedition to Russia and wrote, with others, The Geology…