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Millstone Anatomy
Millstones or mill stones are stones used in gristmills, for grinding wheat or other grains. They are sometimes referred to as grindstones or grinding stones. Millstones come in pairs: a convex stationary base known as the ''bedstone'' and a concave ''runner stone'' that rotates. The movement of the runner on top of the bedstone creates a "scissoring" action that grinds grain trapped between the stones. Millstones are constructed so that their shape and configuration help to channel ground flour to the outer edges of the mechanism for collection. The runner stone is supported by a cross-shaped metal piece (millrind or rynd) fixed to a "mace head" topping the main shaft or spindle leading to the driving mechanism of the mill (wind, water (including tide) or other means). History The earliest evidence for stones used to grind food is found in northern Australia, at the Madjedbebe rock shelter in Arnhem Land, dating back around 60,000 years. Grinding stones or grindstone ...
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Millstone Anatomy
Millstones or mill stones are stones used in gristmills, for grinding wheat or other grains. They are sometimes referred to as grindstones or grinding stones. Millstones come in pairs: a convex stationary base known as the ''bedstone'' and a concave ''runner stone'' that rotates. The movement of the runner on top of the bedstone creates a "scissoring" action that grinds grain trapped between the stones. Millstones are constructed so that their shape and configuration help to channel ground flour to the outer edges of the mechanism for collection. The runner stone is supported by a cross-shaped metal piece (millrind or rynd) fixed to a "mace head" topping the main shaft or spindle leading to the driving mechanism of the mill (wind, water (including tide) or other means). History The earliest evidence for stones used to grind food is found in northern Australia, at the Madjedbebe rock shelter in Arnhem Land, dating back around 60,000 years. Grinding stones or grindstone ...
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Arnhem Land
Arnhem Land is a historical region of the Northern Territory of Australia, with the term still in use. It is located in the north-eastern corner of the territory and is around from the territory capital, Darwin. In 1623, Dutch East India Company captain Willem Joosten van Colster (or Coolsteerdt) sailed into the Gulf of Carpentaria and Cape Arnhem is named after his ship, the ''Arnhem'', which itself was named after the city of Arnhem in the Netherlands. The area covers about and has an estimated population of 16,000, of whom 12,000 are Aboriginal and Torres Strait Islander people. Two regions are often distinguished as East Arnhem (Land) and West Arnhem (Land), and North-east Arnhem Land is known to the local Yolŋu people as Miwatj. The region's service hub is Nhulunbuy, east of Darwin, set up in the early 1970s as a mining town for bauxite. Other major population centres are Yirrkala (just outside Nhulunbuy), Gunbalanya (formerly Oenpelli), Ramingining, and Maningrida. ...
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Siliceous Rock
Siliceous rocks are sedimentary rocks that have silica (SiO2) as the principal constituent. The most common siliceous rock is chert; other types include diatomite. They commonly form from silica-secreting organisms such as radiolarians, diatoms, or some types of sponges Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through .... References Sedimentary rocks {{Petrology-stub ...
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Smelting
Smelting is a process of applying heat to ore, to extract a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal base behind. The reducing agent is commonly a fossil fuel source of carbon, such as coke—or, in earlier times, charcoal. The oxygen in the ore binds to carbon at high temperatures due to the lower potential energy of the bonds in carbon dioxide (). Smelting most prominently takes place in a blast furnace to produce pig iron, which is converted into steel. The carbon source acts as a chemical reactant to remove oxygen from the ore, yielding the purified metal element as a product. The carbon source is oxidized in two stages. First, the carbon (C) combusts with oxygen (O2) in the air to produce carbon monoxide (CO). Second, the ...
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Quern-stone
Quern-stones are stone tools for hand-grinding a wide variety of materials. They are used in pairs. The lower stationary stone of early examples is called a saddle quern, while the upper mobile stone is called a muller, rubber or handstone. The upper stone was moved in a back-and-forth motion across the saddle quern. Later querns are known as rotary querns. The central hole of a rotary quern is called the eye, and a dish in the upper surface is known as the hopper. A handle slot contained a handle which enabled the rotary quern to be rotated. They were first used in the Neolithic era to grind cereals into flour. Uses of quern-stones An old Gaelic proverb is "The quern performs best when the grindstone has been pitted." Design of quern-stones The upper stones were usually concave while the lower ones were convex. Quern-stones are frequently identifiable by their grooved working surfaces which enabled the movement of flour. Sometimes a millrind was present as a piece of wood (or o ...
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Rhizomes
In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow horizontally. The rhizome also retains the ability to allow new shoots to grow upwards. A rhizome is the main stem of the plant that runs underground horizontally. A stolon is similar to a rhizome, but a stolon sprouts from an existing stem, has long internodes, and generates new shoots at the end, such as in the strawberry The garden strawberry (or simply strawberry; ''Fragaria × ananassa'') is a widely grown hybrid species of the genus '' Fragaria'', collectively known as the strawberries, which are cultivated worldwide for their fruit. The fruit is widely ap ... plant. In general, rhizomes have short internodes, send out roots from the bottom of the nodes, and generate new upward-growing shoots from the top of the nodes. A stem tub ...
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Grain
A grain is a small, hard, dry fruit (caryopsis) – with or without an attached hull layer – harvested for human or animal consumption. A grain crop is a grain-producing plant. The two main types of commercial grain crops are cereals and legumes. After being harvested, dry grains are more durable than other staple foods, such as starchy fruits (plantains, breadfruit, etc.) and tubers ( sweet potatoes, cassava, and more). This durability has made grains well suited to industrial agriculture, since they can be mechanically harvested, transported by rail or ship, stored for long periods in silos, and milled for flour or pressed for oil. Thus, the grain market is a major global commodity market that includes crops such as maize, rice, soybeans, wheat and other grains. Grains and cereal Grains and cereal are synonymous with caryopses, the fruits of the grass family. In agronomy and commerce, seeds or fruits from other plant families are called grains if they resemble c ...
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Upper Paleolithic
The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age. Very broadly, it dates to between 50,000 and 12,000 years ago (the beginning of the Holocene), according to some theories coinciding with the appearance of behavioral modernity in early modern humans, until the advent of the Neolithic Revolution and agriculture. Anatomically modern humans (i.e. ''Homo sapiens'') are believed to have emerged in Africa around 300,000 years ago, it has been argued by some that their ways of life changed relatively little from that of archaic humans of the Middle Paleolithic, until about 50,000 years ago, when there was a marked increase in the diversity of Artefact (archaeology), artefacts found associated with modern human remains. This period coincides with the most common date assigned to early human migrations, expansion of modern humans from Africa throughout Asia and Eurasia, which contributed to the Neanderthal extinction, ex ...
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Neolithic
The Neolithic period, or New Stone Age, is an Old World archaeological period and the final division of the Stone Age. It saw the Neolithic Revolution, a wide-ranging set of developments that appear to have arisen independently in several parts of the world. This "Neolithic package" included the introduction of farming, domestication of animals, and change from a hunter-gatherer lifestyle to one of settlement. It began about 12,000 years ago when farming appeared in the Epipalaeolithic Near East, and later in other parts of the world. The Neolithic lasted in the Near East until the transitional period of the Chalcolithic (Copper Age) from about 6,500 years ago (4500 BC), marked by the development of metallurgy, leading up to the Bronze Age and Iron Age. In other places the Neolithic followed the Mesolithic (Middle Stone Age) and then lasted until later. In Ancient Egypt, the Neolithic lasted until the Protodynastic period, 3150 BC.Karin Sowada and Peter Grave. Egypt in th ...
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Victorian Government
The Victoria State Government, also referred to as just the Victorian Government, is the state-level authority for Victoria, Australia. Like all state governments, it is formed by three independent branches: the executive, the judicial, and the parliament. As a parliamentary constitutional monarchy, the State Government was first formed in 1851 when Victoria first gained the right to responsible government. The Constitution of Australia regulates the relationship between the Victorian Government and the Australian Government, and cedes legislative and judicial supremacy to the federal government on conflicting matters. The Victoria State Government enforces acts passed by the parliament through government departments, statutory authorities, and other public agencies. The Government is formally presided over by the Governor, who exercises executive authority granted by the state's constitution through the Executive Council, a body consisting of senior cabinet ministers. In re ...
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Aboriginal Victorians
Aboriginal Victorians, the Aboriginal Australians of Victoria (Australia), Victoria, Australia, occupied the land for tens of thousands of years prior to European settlement of Australia, European settlement. Aboriginal people have lived a semi-nomadic existence of fishing, hunting and gathering, and farming eels in Victoria for at least 40,000 years. The Aboriginal people of Victoria had developed a varied and complex set of languages, tribal alliances, beliefs and social customs that involved totemism, superstition, initiation and burial rites, and tribal Moiety (kinship), moieties. History Prehistory There is some evidence to show that people were living in the Maribyrnong River valley, near present-day Keilor, about 40,000 years ago, according to Gary Presland. At the Keilor archaeological site a human hearth excavated in 1971 was radiocarbon-dated to about 31,000 years Before Present, BP, making Keilor one of the earliest sites of human habitation in Australia.Gary Presla ...
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Pestle
Mortar and pestle is a set of two simple tools used from the Stone Age to the present day to prepare ingredients or substances by crushing and grinding them into a fine paste or powder in the kitchen, laboratory, and pharmacy. The ''mortar'' () is characteristically a bowl, typically made of hard wood, metal, ceramic, or hard stone such as granite. The ''pestle'' (, also ) is a blunt, club-shaped object. The substance to be ground, which may be wet or dry, is placed in the mortar where the pestle is pounded, pressed, and rotated into the substance until the desired texture is achieved. Mortars and pestles have been used in cooking since prehistory; today they are typically associated with the profession of pharmacy due to their historical use in preparing medicines. They are used in chemistry settings for pulverizing small amounts of chemicals; in arts and cosmetics for pulverizing pigments, binders, and other substances; in ceramics for making grog; in masonry and in other typ ...
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