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Fire-setting
Fire-setting is a method of traditional mining used most commonly from prehistoric times up to the Middle Ages. Fires were set against a rock face to heat the stone, which was then doused with liquid, causing the stone to fracture by thermal shock. Rapid heating causes thermal shock by itself—without subsequent cooling—by producing different degrees of expansion in different parts of the rock (and in other materials). In practice, rapid cooling may or may not have been helpful to produce the desired effect. Some experiments have suggested that the water (or any other liquid) did not have a noticeable effect on the rock, but rather helped the miners' progress by quickly cooling down the area after the fire. This technique was best performed in opencast mines where the smoke and fumes could dissipate safely. The technique was very dangerous in underground workings without adequate ventilation. The method became largely redundant with the growth in use of explosives. Altho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stoping (mining Method)
Stoping is the process of extracting the desired ore or other mineral from an underground mining, mine, leaving behind an open space known as a stope. Stoping is used when the Country rock (geology), country rock is sufficiently strong not to collapse into the stope, although in most cases artificial support is also provided. The earliest forms of stoping were conducted with hand tools or by fire-setting; later gunpowder was introduced. From the 19th century onward, various other explosives, power-tools, and machines came into use. As mining progresses the stope is often backfilled with tailings, or when needed for strength, a mixture of tailings and cement. In old mines, stopes frequently collapse at a later time, leaving craters or Flash (lake), flashes at the surface. They are an unexpected danger when records of underground mining have been lost with the passage of time. Stoping is considered "productive work", and is contrasted with "deadwork", the work required merely to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traditional Mining
Traditional mining, also known as old-school mining, is a mining method involving the use of simple manual tools, such as shovels, pickaxes, hammers, chisels and pans. It is done in both surface and underground environments. Until the early 1900s, traditional mining was widely used throughout the world. It is still a used mining method in some countries, including Colombia and Peru in South America and Niger in Africa. In traditional surface and underground mining, hammers and chisels with pickaxes and shovels are used. Minecarts are used to move ore and other materials in the process of mining. Pans are used for placer mining operations, such as gold panning. The traditional method of cracking rock was fire-setting, which involved heating the rock with fire to expand it. Once the rock was heated by fire it was quenched with water to break it. Fire-setting was one of the most effective rock breaking methods until 1867 when Alfred Nobel invented dynamite. Traditional mining operat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold
Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal, a group 11 element, and one of the noble metals. It is one of the least reactivity (chemistry), reactive chemical elements, being the second-lowest in the reactivity series. It is solid under standard temperature and pressure, standard conditions. Gold often occurs in free elemental (native state (metallurgy), native state), as gold nugget, nuggets or grains, in rock (geology), rocks, vein (geology), veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as in electrum), naturally alloyed with other metals like copper and palladium, and mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naturalis Historia
The ''Natural History'' () is a Latin work by Pliny the Elder. The largest single work to have survived from the Roman Empire to the modern day, the ''Natural History'' compiles information gleaned from other ancient authors. Despite the work's title, its subject area is not limited to what is today understood by natural history; Pliny himself defines his scope as "the natural world, or life". It is encyclopedic in scope, but its structure is not like that of a modern encyclopedia. It is the only work by Pliny to have survived, and the last that he published. He published the first 10 books in AD 77, but had not made a final revision of the remainder at the time of Pliny the Elder#Death, his death during the Eruption of Mount Vesuvius in 79 AD, AD 79 eruption of Vesuvius. The rest was published posthumously by Pliny's nephew, Pliny the Younger. The work is divided into 37 books, organised into 10 volumes. These cover topics including astronomy, mathematics, geography, ethn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Shock
Thermal shock is a phenomenon characterized by a rapid change in temperature that results in a transient mechanical load on an object. The load is caused by the differential expansion of different parts of the object due to the temperature change. This differential expansion can be understood in terms of strain, rather than stress. When the strain exceeds the tensile strength of the material, it can cause cracks to form, and eventually lead to structural failure. Methods to prevent thermal shock include: * Minimizing the thermal gradient by changing the temperature gradually * Increasing the thermal conductivity of the material * Reducing the coefficient of thermal expansion of the material * Increasing the strength of the material * Introducing compressive stress in the material, such as in tempered glass * Decreasing the Young's modulus of the material * Increasing the toughness of the material through crack tip blunting or crack deflection, utilizing the process of pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliny The Elder
Gaius Plinius Secundus (AD 23/24 79), known in English as Pliny the Elder ( ), was a Roman Empire, Roman author, Natural history, naturalist, and naval and army commander of the early Roman Empire, and a friend of the Roman emperor, emperor Vespasian. He wrote the encyclopedic (''Natural History''), a comprehensive thirty-seven-volume work covering a vast array of topics on human knowledge and the natural world, which became an editorial model for encyclopedias. He spent most of his spare time studying, writing, and investigating natural and geographic phenomena in the field. Among Pliny's greatest works was the twenty-volume ''Bella Germaniae'' ("The History of the German Wars"), which is Lost literary work, no longer extant. ''Bella Germaniae'', which began where Aufidius Bassus' ''Libri Belli Germanici'' ("The War with the Germans") left off, was used as a source by other prominent Roman historians, including Plutarch, Tacitus, and Suetonius. Tacitus may have used ''Bella Ger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Egyptian
Ancient Egypt () was a cradle of civilization concentrated along the lower reaches of the Nile River in Northeast Africa. It emerged from prehistoric Egypt around 3150BC (according to conventional Egyptian chronology), when Upper and Lower Egypt were amalgamated by Menes, who is believed by the majority of List of Egyptologists, Egyptologists to have been the same person as Narmer. The history of ancient Egypt unfolded as a series of stable kingdoms interspersed by the "Periodization of ancient Egypt, Intermediate Periods" of relative instability. These stable kingdoms existed in one of three periods: the Old Kingdom of Egypt, Old Kingdom of the Early Bronze Age; the Middle Kingdom of Egypt, Middle Kingdom of the Middle Bronze Age; or the New Kingdom of Egypt, New Kingdom of the Late Bronze Age. The pinnacle of ancient Egyptian power was achieved during the New Kingdom, which extended its rule to much of Nubia and a considerable portion of the Levant. After this period, Egypt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bibliotheca Historica
''Bibliotheca historica'' (, ) is a work of Universal history (genre), universal history by Diodorus Siculus. It consisted of forty books, which were divided into three sections. The first six books are geographical in theme, and describe the history and culture of Egypt (book I), of Mesopotamia, India, Scythia, and Arabia (II), of North Africa (III), and of Greece and Europe (IV–VI). In the next section (books VII–XVII), he recounts human history starting with the Trojan War, down to the death of Alexander the Great. The last section (books XVII to the end) concern the historical events from the Diadochi, successors of Alexander down to either 60 BC or the beginning of Julius Caesar, Caesar's Gallic War in 59 BC. (The end has been lost, so it is unclear whether Diodorus reached the beginning of the Gallic War, as he promised at the beginning of his work, or, as evidence suggests, old and tired from his labors he stopped short at 60 BC.) He selected the name "Bibliotheca" in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diodorus Siculus
Diodorus Siculus or Diodorus of Sicily (; 1st century BC) was an ancient Greece, ancient Greek historian from Sicily. He is known for writing the monumental Universal history (genre), universal history ''Bibliotheca historica'', in forty books, fifteen of which survive intact, between 60 and 30 BC. The history is arranged in three parts. The first covers mythic history up to the destruction of Troy, arranged geographically, describing regions around the world from Egypt, India and Arabia to Europe. The second covers the time from the Trojan War to the death of Alexander the Great. The third covers the period to about 60 BC. ''Bibliotheca'', meaning 'library', acknowledges that he was drawing on the work of many other authors. Life According to his own work, he was born in Agira, Agyrium in Sicily (now called Agira). With one exception, classical antiquity, antiquity affords no further information about his life and doings beyond his written works. Only Jerome, in his ''Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
County Cork
County Cork () is the largest and the southernmost Counties of Ireland, county of Republic of Ireland, Ireland, named after the city of Cork (city), Cork, the state's second-largest city. It is in the Provinces of Ireland, province of Munster and the Southern Region, Ireland, Southern Region. Its largest market towns are Mallow, County Cork, Mallow, Macroom, Midleton, and Skibbereen. , the county had a population of 584,156, making it the third-List of Irish counties by population, most populous county in Ireland. Cork County Council is the Local government in the Republic of Ireland, local authority for the county, while Cork City Council governs the city of Cork and its environs. Notable Corkonians include Michael Collins (Irish leader), Michael Collins, Jack Lynch, Mother Jones, Roy Keane, Sonia O'Sullivan, Cillian Murphy and Graham Norton. Cork borders four other counties: County Kerry, Kerry to the west, County Limerick, Limerick to the north, County Tipperary, Tipperary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goleen
Goleen () is a small rural village in County Cork on the south-western tip of Ireland. Farming, tourism and construction work are among the main occupations of the local people. Location Goleen is located towards the south-western end of the Mizen Peninsula, in West Cork. The land surrounding the village is unsuitable for farming, being hilly and rocky with limited soil cover. Mizen Head, at the southern tip of the Mizen peninsula, about five miles from the village, is often claimed to be the most southerly point on the island of Ireland, but is in fact the country's most southwesterly point. The distinction of being Ireland's most southerly point belongs to nearby Brow Head, from where Guglielmo Marconi experimented with transatlantic radio signals at the beginning of the 20th century. Amenities The village has four pubs, a small shop, and a petrol station. The town also has a community pitch on which locals play Gaelic football and soccer. In the sports hall beside the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrol (state)
Tyrol ( ; ; ) is an Austrian Provinces of Austria, federal state. It comprises the Austrian part of the historical County of Tyrol, Princely County of Tyrol. It is a constituent part of the present-day Euroregion Tyrol–South Tyrol–Trentino (together with South Tyrol and Trentino in Italy). The capital of Tyrol is Innsbruck. Geography Tyrol is separated into two parts, divided by a strip of Salzburg (federal state), Salzburg State. The two constituent parts of Tyrol are the northern and larger North Tyrol () and the southeastern and smaller East Tyrol ('). Salzburg State lies to the east of North Tyrol, while on the south Tyrol has a border to the Italy, Italian province of South Tyrol, which was part of the Austro-Hungarian Empire before the First World War. With a land area of , Tyrol is the third-largest federal state in Austria. North Tyrol shares its borders with the federal states Salzburg in the east and Vorarlberg in the west. In the north, it adjoins the Germany ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
