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Arrowhead
An arrowhead or point is the usually sharpened and hardened tip of an arrow, which contributes a majority of the projectile mass and is responsible for impacting and penetrating a target, or sometimes for special purposes such as signaling. The earliest arrowheads were made of stone and of organic materials; as human civilizations progressed, other alloy materials were used. Arrowheads are important archaeological artifacts; they are a subclass of projectile points. Modern enthusiasts still "produce over one million brand-new spear and arrow points per year". A craftsman who manufactures arrowheads is called an arrowsmith. History In the Stone Age, people used sharpened bone, flintknapped stones, flakes, and chips and bits of rock as weapons and tools. Such items remained in use throughout human civilization, with new materials used as time passed. As archaeological artifacts such objects are classed as projectile points, without specifying whether they were ...
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Arrow
An arrow is a fin-stabilized projectile launched by a bow. A typical arrow usually consists of a long, stiff, straight shaft with a weighty (and usually sharp and pointed) arrowhead attached to the front end, multiple fin-like stabilizers called fletchings mounted near the rear, and a slot at the rear end called a nock for engaging the bowstring. A container or bag carrying additional arrows for convenient reloading is called a quiver. The use of bows and arrows by humans predates recorded history and is common to most cultures. A craftsman who makes arrows is a fletcher, and one who makes arrowheads is an arrowsmith.Paterson ''Encyclopaedia of Archery'' p. 56 History The oldest evidence of likely arrowheads, dating to years ago, were found in Sibudu Cave, current South Africa.Backwell L, d'Errico F, Wadley L.(2008). Middle Stone Age bone tools from the Howiesons Poort layers, Sibudu Cave, South Africa. Journal of Archaeological Science, 35:1566–1580. Backwell L ...
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Bow And Arrow
The bow and arrow is a ranged weapon system consisting of an elasticity (physics), elastic launching device (bow) and long-shafted projectiles (arrows). Humans used bows and arrows for hunting and aggression long before recorded history, and the practice was common to many prehistoric cultures. They were important weapon of war, weapons of war from ancient history until the early modern period, when they were rendered increasingly obsolete by the development of the more powerful and accurate firearms. Today, bows and arrows are mostly used for bowhunting, hunting and Modern competitive archery, sports. Archery is the art, practice, or skill of using bows to shooting, shoot arrows.Paterson ''Encyclopaedia of Archery'' p. 17 A person who shoots arrows with a bow is called a bowman or an archer. Someone who makes bows is known as a bowyer,Paterson ''Encyclopaedia of Archery'' p. 31 someone who makes arrows is a fletching, fletcher,Paterson ''Encyclopaedia of Archery'' p. 56 and some ...
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Projectile Point
In archaeological terminology, a projectile point is an object that was hafted to a weapon that was capable of being thrown or projected, such as a javelin, dart, or arrow. They are thus different from weapons presumed to have been kept in the hand, such as knives, spears, axes, hammers, and maces. Stone tools, including projectile points, were often lost or discarded and are relatively plentiful, especially at archaeological sites. They provide useful clues to the human past, including prehistoric trade. A distinctive form of point, identified though lithic analysis of the way it was made, is often a key diagnostic factor in identifying an archaeological industry or culture. Scientific techniques exist to track the specific kinds of rock or minerals that were used to make stone tools in various regions back to their original sources. As well as stone, projectile points were also made of worked wood, bone, antler, horn, or ivory; all of these are less common in the Am ...
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Alloy
An alloy is a mixture of chemical elements of which in most cases at least one is a metal, metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they are made. The vast majority of metals used for commercial purposes are alloyed to improve their properties or behavior, such as increased strength, hardness or corrosion resistance. Metals may also be alloyed to reduce their overall cost, for instance alloys of gold and Copper(II) sulfate, copper. A typical example of an alloy is SAE 304 stainless steel, 304 grade stainless steel which is commonly used for kitchen utensils, pans, knives and forks. Sometime also known as 18/8, it as an alloy consisting broadly of 74% iron, 18% chromium and 8% nickel. The chromium and nickel alloying elements add strength and hardness to the majority iron element, but their main function is ...
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Obsidian
Obsidian ( ) is a naturally occurring volcanic glass formed when lava extrusive rock, extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Produced from felsic lava, obsidian is rich in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. It is commonly found within the margins of rhyolite, rhyolitic lava flows known as obsidian flows. These flows have a high content of silicon dioxide, silica, giving them a high viscosity. The high viscosity inhibits the atomic diffusion, diffusion of atoms through the lava, which inhibits the first step (nucleation) in the formation of mineral crystals. Together with rapid cooling, this results in a natural glass forming from the lava. Obsidian is hard, Brittleness, brittle, and amorphous; it therefore Fracture (mineralogy)#Conchoidal fracture, fractures with sharp edges. In the past, it was used to manufacture cutting and piercing tools, and it has been used experimentally as s ...
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Glue
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing, mechanical fastenings, and welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, the cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by ''reactive'' or ''non-reactive'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized eithe ...
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Sibudu Cave
Sibudu Cave is a rock shelter in a sandstone cliff in northern KwaZulu-Natal, South Africa. It is an important Middle Stone Age site occupied, with some gaps, from years ago to years ago. Evidence of some of the earliest examples of modern human technology has been found in the shelter (although the earliest known spears date back years). The evidence in the shelter includes the earliest bone arrow ( years old), and the earliest stone arrows (64,000 years old), the earliest needle ( years old), the earliest use of heat-treated mixed compound gluing ( years ago), and an example of the use of bedding ( years ago) which for a while was the oldest known example (an older example from years ago was recently discovered at Border Cave, South Africa).Wadley L, Sievers C, Bamford M, Goldberg P, Berna F, Miller C. (2011)Middle Stone Age Bedding Construction and Settlement Patterns at Sibudu, South Africa Science 9 December 2011: Vol. 334 no. 6061 pp. 1388–1391. An older example is n ...
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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 ...
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Tang (tools)
A tang or shank is the back portion of the blade component of a tool where it extends into stock material or connects to a handle – as on a knife, sword A sword is an edged and bladed weapons, edged, bladed weapon intended for manual cutting or thrusting. Its blade, longer than a knife or dagger, is attached to a hilt and can be straight or curved. A thrusting sword tends to have a straighter ..., spear, arrowhead, chisel, file, coulter, pike, scythe, screwdriver, etc. One can classify various tang designs by their appearance, by the manner in which they attach to a handle, and by their length in relation to the handle. ''Nakago'' is the term in Japanese, used especially when referring to the tang of the katana or the wakizashi. Full vs partial tang A full tang extends the full length of the grip-portion of a handle, versus a ''partial'' tang which does not. A full tang may or may not be as wide as the handle itself, but will still run the full length of ...
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Cognition
Cognition is the "mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception, attention, thought, imagination, intelligence, the formation of knowledge, memory and working memory, judgment and evaluation, reasoning and computation, problem-solving and decision-making, comprehension and production of language. Cognitive processes use existing knowledge to discover new knowledge. Cognitive processes are analyzed from very different perspectives within different contexts, notably in the fields of linguistics, musicology, anesthesia, neuroscience, psychiatry, psychology, education, philosophy, anthropology, biology, systemics, logic, and computer science. These and other approaches to the analysis of cognition (such as embodied cognition) are synthesized in the developing field of cognitive science, a progressively autonomou ...
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