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Gold Rush
A gold rush or gold fever is a discovery of gold—sometimes accompanied by other precious metals and rare-earth minerals—that brings an onrush of miners seeking their fortune. Major gold rushes took place in the 19th century in Australia, Greece, New Zealand, Brazil, Chile, South Africa, the United States, and Canada while smaller gold rushes took place elsewhere. In the 19th century, the wealth that resulted was distributed widely because of reduced migration costs and low barriers to entry. While gold mining itself proved unprofitable for most diggers and mine owners, some people made large fortunes, and merchants and transportation facilities made large profits. The resulting increase in the world's gold supply stimulated global trade and investment. Historians have written extensively about the mass migration, trade, colonization, and environmental history associated with gold rushes. Gold rushes were typically marked by a general buoyant feeling of a "free-for-al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California Clipper 500
California () is a state in the Western United States that lies on the Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares an international border with the Mexican state of Baja California to the south. With almost 40million residents across an area of , it is the largest state by population and third-largest by area. Prior to European colonization, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. European exploration in the 16th and 17th centuries led to the colonization by the Spanish Empire. The area became a part of Mexico in 1821, following its successful war for independence, but was ceded to the United States in 1848 after the Mexican–American War. The California gold rush started in 1848 and led to social and demographic changes, including depopulation of Indigenous tribes. It organized itself and was admitted as the 31st state in 1850 as a free state, foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Frontier
The American frontier, also known as the Old West, and popularly known as the Wild West, encompasses the geography, history, folklore, and culture associated with the forward wave of American expansion in mainland North America that began with European colonial settlements in the early 17th century and ended with the admission of the last few contiguous western territories as states in 1912. This era of massive migration and settlement was particularly encouraged by President Thomas Jefferson following the Louisiana Purchase, giving rise to the expansionist attitude known as "manifest destiny" and historians' " Frontier Thesis". The legends, historical events and folklore of the American frontier, known as the frontier myth, have embedded themselves into United States culture so much so that the Old West, and the Western genre of media specifically, has become one of the defining features of American national identity. Periodization Historians have debated at length as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold Dredge
A gold dredge is a placer mining machine that extracts gold from sand, gravel, and dirt using water and mechanical methods. Original gold dredges were large, multi-story machines built in the first half of the 1900s. In modern times the term refers to small suction machines marketed as "gold dredges" to individuals seeking gold. Concept The basic concept of retrieving gold via placer mining has not changed since antiquity. The concept is that the gold in sand or soil will settle to the bottom because gold is heavy/dense, and dirt, sand and rock will wash away, leaving the gold behind. The original methods to perform placer mining involved gold panning, sluice boxes, and rockers. Each method involves washing sand, gravel and dirt in water. Gold then settles to the bottom of the pan, or into the bottom of the riffles of the sluice box. A gold dredge operates in a similar manner but on a larger scale. A large gold dredge uses a mechanical method to excavate material (sand, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Mining
Hydraulic mining is a form of mining that uses high-pressure jets of water to dislodge rock material or move sediment.Paul W. Thrush, ''A Dictionary of Mining, Mineral, and Related Terms'', US Bureau of Mines, 1968, p.560. In the placer mining of gold or tin, the resulting water-sediment slurry is directed through Sluice boxes to remove the gold or tin. It is also used in mining kaolin and coal. Hydraulic mining developed from ancient Roman techniques that used water to excavate soft underground deposits. Its modern form, using pressurized water Jet (fluid), jets produced by a nozzle called a "monitor", came about in the 1850s during the California Gold Rush in the United States. Though successful in extracting gold-rich minerals, the widespread use of the process resulted in extensive environmental damage, such as increased flooding and erosion, and sediment blocking waterways and covering farm fields. These problems led to its legal regulation. Hydraulic mining has been used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Sluicing
Placer mining () is the mining of stream bed deposits for minerals. This may be done by open-pit mining or by various surface excavating equipment or tunneling equipment. Placer mining is frequently used for precious metal deposits (particularly gold) and gemstones, both of which are often found in alluvial deposits—deposits of sand and gravel in modern or ancient stream beds, or occasionally glacial deposits. The metal or gemstones, having been moved by stream flow from an original source such as a vein, are typically only a minuscule portion of the total deposit. Since gems and heavy metals like gold are considerably denser than sand, they tend to accumulate at the base of placer deposits. Placer deposits can be as young as a few years old, such as the Canadian Queen Charlotte beach gold placer deposits, or billions of years old like the Elliot Lake uranium paleoplacer within the Huronian Supergroup in Canada. The containing material in an alluvial placer mine may be too lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Mining In Dutch Flat, California, Between 1857 And 1870
Hydraulics () is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which concerns gases. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on applied engineering using the properties of fluids. In its fluid power applications, hydraulics is used for the generation, control, and transmission of power by the use of pressurized liquids. Hydraulic topics range through some parts of science and most of engineering modules, and they cover concepts such as pipe flow, dam design, fluidics, and fluid control circuitry. The principles of hydraulics are in use naturally in the human body within the vascular system and erectile tissue. ''Free surface hydraulics'' is the branch of hydraulics dealing with free surface flow, such as occurring in rivers, canals, lakes, estuaries, and seas. Its sub- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wooden Gold Sluice In California Between 1890 And 1915
Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include the same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree, it performs a mechanical-support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients among the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips, or fibers. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the production of p ... [...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 Greece
Ancient Greece () was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity (), that comprised a loose collection of culturally and linguistically related city-states and communities. Prior to the Roman period, most of these regions were officially unified only once under the Kingdom of Macedon from 338 to 323 BC. In Western history, the era of classical antiquity was immediately followed by the Early Middle Ages and the Byzantine period. Three centuries after the decline of Mycenaean Greece during the Bronze Age collapse, Greek urban poleis began to form in the 8th century BC, ushering in the Archaic period and the colonization of the Mediterranean Basin. This was followed by the age of Classical Greece, from the Greco-Persian Wars to the death of Alexander the Great in 323 BC, and which included the Golden Age of Athens and the Peloponnesian War. The u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
