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Hand Axe
A hand axe (or handaxe or Acheulean hand axe) is a Prehistory, prehistoric stone tool with two faces that is the longest-used tool in human history. It is made from stone, usually flint or chert that has been "reduced" and shaped from a larger piece by knapping, or hitting against another stone. They are characteristic of the lower Acheulean and middle Palaeolithic (Mousterian) periods, roughly 1.6 million years ago to about 100,000 years ago, and used by ''Homo erectus'' and other early humans, but rarely by ''Homo sapiens''. Their technical name (biface) comes from the fact that the archetypical model is a generally bifacial (with two wide sides or faces) and almond-shaped (amygdaloidal) lithic flake. Hand axes tend to be Symmetry, symmetrical along their longitudinal Symmetry axis, axis and formed by pressure or percussion. The most common hand axes have a pointed end and rounded base, which gives them their characteristic almond shape, and both faces have been Knapping, knap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadaxe
A broadaxe is a large broad-headed axe. There are two categories of cutting edge on broadaxes, both are used for shaping logs into beams by hewing. On one type, one side is flat, and the other side beveled, a basilled edge, also called a side axe, single bevel, or chisle-edged axe. On the other type, both sides are beveled, sometimes called a double bevel axe, which produces a scalloped cut. On the basilled broadaxe the handle may curve away from the flat side to allow an optimal stance by the hewer in relation to the hewn surface, and to allow clearance for the hewer's hands. The flat blade is to make the surface flat but can only be worked from one direction and is right-handed or left-handed. The double bevel axe has a straight handle and can be swung with either side against the wood. A double-beveled broad axe can be used for chopping or notching as well as hewing. When used for hewing, notches are chopped in the side of the log down to a marked line, a process called scorin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flint Axe
A flint axe was a Flint tool used during prehistoric times to perform a variety of tasks. These were at first just a cut piece of flint stone used as a hand axe but later wooden handles were attached to these axe heads. The stone exhibits a glass-like fracture similar to obsidian, and can be knapped to form large blades. The offcuts were sharp enough to be used a small flint knives, while the larger parts of a knapped nodule could be polished to form an axe-head. They competed with other hard rocks such as greenstone, which were produced at Langdale in the British Lake District and got larger as working continued. They tend to be larger and heavier than the simple axes, and are sometimes known as axe-hammers. There are many different types of flint axes. A specific one that appeared during the Early Stone Age was the core axe. This is an unpolished flint axe that is roughly hewn. The cutting edge is usually the widest part and has a pointed butt. Flake axes are created from the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronze
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals (such as phosphorus) or metalloids (such as arsenic or silicon). These additions produce a range of alloys some of which are harder than copper alone or have other useful properties, such as strength, ductility, or machinability. The archaeological period during which bronze was the hardest metal in widespread use is known as the Bronze Age. The beginning of the Bronze Age in western Eurasia is conventionally dated to the mid-4th millennium BCE (~3500 BCE), and to the early 2nd millennium BCE in China; elsewhere it gradually spread across regions. The Bronze Age was followed by the Iron Age, which started about 1300 BCE and reaching most of Eurasia by about 500 BCE, although bronze continued to be much more widely used than it is in modern times. Because historica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American And British English Spelling Differences
Despite the various list of dialects of English, English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variations being British and American spelling. Many of Comparison of American and British English, the differences between American English, American and British English, British or English in the Commonwealth of Nations, Commonwealth English date back to a time before spelling standards were developed. For instance, some spellings seen as "American" today were once commonly used in Britain, and some spellings seen as "British" were once commonly used in the United States. A "British standard" began to emerge following the 1755 publication of Samuel Johnson's ''A Dictionary of the English Language'', and an "American standard" started following the work of Noah Webster and, in particular, his ''Webster's Dictionary, An American Dictionary of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stone Age
The Stone Age was a broad prehistory, prehistoric period during which Rock (geology), stone was widely used to make stone tools with an edge, a point, or a percussion surface. The period lasted for roughly 3.4 million years and ended between 4000 Anno Domini, BC and 2000 BC, with the advent of metalworking. It therefore represents nearly 99.3% of human history. Though some simple metalworking of malleable metals, particularly the use of Goldsmith, gold and Coppersmith, copper for purposes of ornamentation, was known in the Stone Age, it is the melting and smelting of copper that marks the end of the Stone Age. In Western Asia, this occurred by about 3000 BC, when bronze became widespread. The term Bronze Age is used to describe the period that followed the Stone Age, as well as to describe cultures that had developed techniques and technologies for working copper alloys (bronze: originally copper and arsenic, later copper and tin) into tools, supplanting ston ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable, unalloyed metallic form. This means that copper is a native metal. This led to very early human use in several regions, from . Thousands of years later, it was the first metal to be smelted from sulfide ores, ; the first metal to be cast into a shape in a mold, ; and the first metal to be purposely alloyed with another metal, tin, to create bronze, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hatchet
A hatchet (from the Old French language, Old French , a diminutive form of ''hache'', 'axe' of Germanic origin) is a Tool, single-handed striking tool with a sharp blade on one side used to cut and split wood, and a hammerhead on the other side. Hatchets may also be used for hewing when making flattened surfaces on logs; when the hatchet head is optimized for this purpose it is called a hewing hatchet. The earliest known use of the noun hatchet is in the Middle English period (1150—1500) Although 'hand axe' and 'hatchet' are often used interchangeably in contemporary usage, 19th and 20th century American manufacturers and retailers (Collins, Kelly, Vaughan, Warren, Mann; Simmons, Shapleigh, Sears, et al.) unanimously distinguished hatchets from hand axes in their product catalogs, listing them in separate groupings. A ''hand axe'' (also known by terms including "camp axe", "belt axe", "hunters axe" and others) is a short-handled woods tool. A ''hatchet'' is a short-handled co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethiopia
Ethiopia, officially the Federal Democratic Republic of Ethiopia, is a landlocked country located in the Horn of Africa region of East Africa. It shares borders with Eritrea to the north, Djibouti to the northeast, Somalia to the east, Kenya to the south, South Sudan to the west, and Sudan to the northwest. Ethiopia covers a land area of . , it has around 128 million inhabitants, making it the List of countries and dependencies by population, thirteenth-most populous country in the world, the List of African countries by population, second-most populous in Africa after Nigeria, and the most populous landlocked country on Earth. The national capital and largest city, Addis Ababa, lies several kilometres west of the East African Rift that splits the country into the African Plate, African and Somali Plate, Somali tectonic plates. Early modern human, Anatomically modern humans emerged from modern-day Ethiopia and set out for the Near East and elsewhere in the Middle Paleolithi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simple Machine
A simple machine is a machine, mechanical device that changes the Direction (geometry) , direction or Magnitude_(mathematics) , magnitude of a force. In general, they can be defined as the simplest Mechanism (engineering) , mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: * Lever * Wheel and axle * Pulley * Inclined plane * Wedge (mechanical device), Wedge * Screw (simple machine), Screw A simple machine uses a single applied force to do Mechanical work, work against a single load force. Ignoring friction losses, the work done on the load is equal to the work done by the applied force. The machine can increase the amount of the output force, at the cost of a proportional decrease in the distance moved by the load. The ratio of the output to the applied force is called the ''mechanical advantage''. Simple machines can be regarded as the eleme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shang Bronze Yue 2
The Shang dynasty (), also known as the Yin dynasty (), was a Chinese royal dynasty that ruled in the Yellow River valley during the second millennium BC, traditionally succeeding the Xia dynasty and followed by the Western Zhou dynasty. The classic account of the Shang comes from texts such as the ''Book of Documents'', ''Bamboo Annals'' and ''Shiji''. Modern scholarship dates the dynasty between the 16th and 11th centuries BC, with more agreement surrounding the end date than beginning date. The Shang dynasty is the earliest dynasty within traditional Chinese history that is firmly supported by archaeological evidence. The archaeological site of Yinxu, near modern-day Anyang, corresponds to the final Shang capital of Yin. Excavations at Yinxu have revealed eleven major royal tombs, the foundations of former palace buildings, and the remains of both animals and humans that were sacrificed in official state rituals. Tens of thousands of bronze, jade, stone, bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
