Birch Tar
Birch bark tar (sometimes referred to as birch bark pitch) is a substance that is synthesized by dry distillation of birch tree bark. Chemical composition Birch bark tar is mainly composed of triterpenoid compounds of the lupane and oleanane family, which can be used as biomarkers to identify birch bark tar in the archaeological record. The most characteristic molecules are betulin and lupeol, which are also present in birch bark. Some of these molecules degrade into other lupane and oleanane skeleton triperpenes. The most commonly found additional molecules are lupenone, betulone, lupa-2,20(29)-dien-28-ol, lupa-2,20(29)-diene and allobetulin. Ancient and modern uses Birch bark tar use as an adhesive began in the Middle Paleolithic. Neanderthals produced tar through dry distillation of birch bark as early as 200,000 years ago. A 2019 study demonstrated that birch bark tar production can be a simpler, more discoverable process by directly burning birch bark under overhangi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Birch Bark
Birch bark or birchbark is the bark of several Eurasian and North American birch trees of the genus ''Betula''. For all practical purposes, birch bark's main layers are the outer dense layer, white on the outside, and the inner porous layer (cambium). For vast majority of crafts, the outer bark is used. In many languages it has a separate name. For example, in Russian "birch bark" is "beryozovaya kora", while the outer birch bark is "beryosta". The strong and water-resistant cardboard-like outer bark can be easily cut, bent, and sewn, which has made it a valuable building, crafting, and writing material, since pre-historic times. Today, birch bark remains a popular type of wood for various handicrafts and arts. Birch bark also contains substances of medicinal and chemical interest. Some of those products (such as betulin) also have fungicidal properties that help preserve bark artifacts, as well as food preserved in bark containers. Collection and storage Removing birch ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Chewing Gum
Chewing gum is a soft, cohesive substance designed to be chewed without being swallowed. Modern chewing gum is composed of gum base, sweeteners, softeners/plasticizers, flavors, colors, and, typically, a hard or powdered polyol coating. Its texture is reminiscent of rubber because of the physical-chemical properties of its polymer, plasticizer, and resin components, which contribute to its elastic-plastic, sticky, chewy characteristics. History The cultural tradition of chewing gum seems to have developed through a convergent evolution process, as traces of this habit have arisen separately in many early civilizations. Each early precursor to chewing gum was derived from natural growths local to the region and was chewed purely out of the instinctual desire to chewing, masticate. Early chewers did not necessarily desire to derive nutritional benefits from their chewable substances but at times sought stimulus (physiology)#Taste, taste stimuli and teeth cleaning or breath-fre ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Ă–tzi
Ă–tzi, also called The Iceman, is the natural mummy of a man who lived between 3350 and 3105 BC. Ă–tzi's remains were discovered on 19 September 1991, in the Ă–tztal Alps (hence the nickname "Ă–tzi", ) at the Austria–Italy border. He is Europe's oldest known natural human mummy, offering an unprecedented view of Chalcolithic (Copper Age) Europeans. Because of the presence of an arrowhead embedded in his left shoulder and various other wounds, researchers believe that Ă–tzi was killed by another person. The nature of his life and the circumstances of his death are the subject of much investigation and speculation. His remains and personal belongings are on exhibit at the South Tyrol Museum of Archaeology in Bolzano, South Tyrol, Italy. Discovery Ă–tzi was found on 19 September 1991 by two German tourists, at an elevation of on the east ridge of the Fineilspitze in the Ă–tztal Alps on the Austrian–Italian border, near Similaun mountain and the Tisenjoch pass. When t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Hafting
Hafting is a process by which an Artifact (archaeology), artifact, often made of bone tool, bone, stone tool, stone, or tool steel, metal is attached to a ''haft'' (handle or strap). This makes the artifact more useful by allowing it to be launched by a Bow and arrow, bow (arrow), thrown by hand (spear), or used with more effective leverage (axe). When constructed properly, hafting can tremendously improve a weapon's damage and range. It is estimated that hafted weapons were most common during the Upper Paleolithic and Middle Paleolithic. It was one of the first tools where Hominini, hominins took separate elements and united them into a single tool. The development of hafting is considered by archaeologists to have been a significant milestone. It was not only an improvement in the technology at the time; it also showed the progression of the human mind toward a world of complex tool-making. Hafting weapons is perhaps best known for its use by humans in prehistory, but it is stil ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Iron Age
The Iron Age () is the final epoch of the three historical Metal Ages, after the Chalcolithic and Bronze Age. It has also been considered as the final age of the three-age division starting with prehistory (before recorded history) and progressing to protohistory (before written history). In this usage, it is preceded by the Stone Age (subdivided into the Paleolithic, Mesolithic and Neolithic) and Bronze Age. These concepts originated for describing Iron Age Europe and the ancient Near East. In the archaeology of the Americas, a five-period system is conventionally used instead; indigenous cultures there did not develop an iron economy in the pre-Columbian era, though some did work copper and bronze. Indigenous metalworking arrived in Australia with European contact. Although meteoric iron has been used for millennia in many regions, the beginning of the Iron Age is defined locally around the world by archaeological convention when the production of Smelting, smelted iron (espe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Neolithic
The Neolithic or New Stone Age (from Ancient Greek, Greek 'new' and 'stone') is an archaeological period, the final division of the Stone Age in Mesopotamia, Asia, Europe and Africa (c. 10,000 BCE to c. 2,000 BCE). 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 History of agriculture, introduction of farming, domestication of animals, and change from a hunter-gatherer lifestyle to one of sedentism, settlement. The term 'Neolithic' was coined by John Lubbock, 1st Baron Avebury, Sir John Lubbock in 1865 as a refinement of the three-age system. The Neolithic began about 12,000 years ago, when farming appeared in the Epipalaeolithic Near East and Mesopotamia, and later in other parts of the world. It lasted in the Near East until the transitional period of the Chalcolithic (Copper Age) from about 6,500 years ago (4500 BCE), marked by the development ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Lashing (ropework)
A lashing is an arrangement of rope, wire, or webbing with linking device used to secure and fasten two or more items together in a somewhat rigid manner. Lashings are most commonly applied to timber poles, and are commonly associated with cargo, containerisation, the Scouting movement, sailors, and gardeners. It has been imagined that the first lashing made by humans was wrapping a few strips of bark around a stone to hold it to a tree branch to make an ax to hunt and build with. In modern times, the same methods are used, but strips of bark and vines have been replaced with natural and synthetic fiber ropes. Scouts and campers use lashings to build camp gadgets and improve their campsites for comfort and convenience, including the building of rafts for transport and competitive events. Lashings are also used in pioneering, the art of creating structures such as bridges and towers, using ropes and wooden spars. There are still areas in the world where lashing spars (or poles ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Rawhide (textile)
Rawhide is a hide or animal skin that has not been exposed to tanning. It is similar to parchment, much lighter in color than leather made by traditional vegetable tanning. Rawhide is more susceptible to water than leather, and it quickly softens and stretches if left wet unless well waterproofed. "Rawhide" laces often sold for boots or baseball gloves are made of normal tanned leather rather than actual rawhide. Rawhide is not pliable when dry and would be unsuitable for that use. Process The skin from buffalo, deer, elk or cattle from which most rawhide originates is prepared by removing all fur, meat and fat. The hide is then usually stretched over a frame before being dried. The resulting material is hard and translucent. It can be shaped by rewetting and forming before being allowed to thoroughly re-dry. It can be rendered more pliable by 'working', i.e. bending repeatedly in multiple directions, often by rubbing it over a post, sometimes traditionally by chewing. I ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fletching
Fletching is the fin-shaped aerodynamic stabilization device attached on arrows, crossbow bolts, Dart (missile), darts, and javelins, typically made from light semi-flexible materials such as feathers or Bark (botany), bark. Each piece of such a device is a fletch, also known as a flight or feather. A fletcher is a person who attaches fletchings to the shaft of arrows. Fletchers were traditionally associated with the Worshipful Company of Fletchers, a guild in the City of London. The word is related to the French word , meaning 'arrow', via the ultimate root of Old Frankish . Description As a noun, ''fletching'' refers collectively to the fins or vanes, each of which individually is known as a fletch. Traditionally, the fletching consists of three matched half-feathers attached near the back of the arrow or shaft of the dart that are equally spaced around its circumference. Four fletchings have also been used. In English archery, the male feather, from a cock, is used on the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Hunter-gatherer
A hunter-gatherer or forager is a human living in a community, or according to an ancestrally derived Lifestyle, lifestyle, in which most or all food is obtained by foraging, that is, by gathering food from local naturally occurring sources, especially wild edible plants but also insects, Fungus, fungi, Honey hunting, honey, Eggs as food, bird eggs, or anything safe to eat, or by hunting game (pursuing or trapping and killing Wildlife, wild animals, including Fishing, catching fish). This is a common practice among most vertebrates that are omnivores. Hunter-gatherer Society, societies stand in contrast to the more Sedentism, sedentary Agrarian society, agricultural societies, which rely mainly on cultivating crops and raising domesticated animals for food production, although the boundaries between the two ways of living are not completely distinct. Hunting and gathering was humanity's original and most enduring successful Competition (biology), competitive adaptation in the nat ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |