|
Drill Presses
A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driverchuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to increased efficiency and ease of use. Drills are commonly used in woodworking, metalworking, construction, machine tool fabrication, construction and utility projects. Specially designed versions are made for miniature applications. History Around 35,000 BC, ''Homo sapiens'' discovered the benefits of the application of rotary tools. This would have rudimentarily consisted of a pointed rock being spun between the hands to bore a hole through another material. This led to the hand drill, a smooth stick, that was sometimes attached to flint point, and was rubbed between the palms. This was used by many ancient civilizations around the world including the Mayans. The earliest perforated artifacts, such as bone, ivory, shells, and antlers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drill Scheme
A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driverchuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to increased efficiency and ease of use. Drills are commonly used in woodworking, metalworking, construction, machine tool fabrication, construction and utility projects. Specially designed versions are made for miniature applications. History Around 35,000 BC, ''Homo sapiens'' discovered the benefits of the application of rotary tools. This would have rudimentarily consisted of a pointed rock being spun between the hands to bore a hole through another material. This led to the hand drill, a smooth stick, that was sometimes attached to flint point, and was rubbed between the palms. This was used by many ancient civilizations around the world including the Mayans. The earliest perforated artifacts, such as bone, ivory, shells, and antler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pump Drill
A pump drill is a simple hand-powered device used to impart a rapid rotating motion to a rod (the ''spindle'' or ''drill shaft''). It can be used for fire making or as a drill to make holes in various materials. It consists of: the drill shaft, a narrow board with a hole through the center, a weight (usually a heavy disc) acting as a flywheel, and a length of cord. The weight is attached to the shaft, near the bottom end, and the hole board is slipped over the top. The cord is run through a hole or slot near the top of the shaft and attached to both ends of the hole board. The length of the cord is such that, at its lowest position, the board lies just above the weight. The end of the shaft usually has a slot or hole that can hold a hard bit that does the actual drilling, either by abrasion or by cutting. For wood, the bit may be an auger bits or a simple triangular blade, that can cut while rotating in either directions. To use, the shaft is first turned by hand so that t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Core Drill
A modern core drill is a drill specifically designed to remove a cylinder of material, much like a hole saw. The material left inside the drill bit is referred to as the ''core''. Core drills used in metal are called annular cutters. Core drills used for concrete and hard rock generally use industrial diamond grit as the abrasive material and may be electrical, pneumatic or hydraulic powered. Core drills are commonly water cooled, and the water also carries away the fine waste as a slurry. For drilling masonry, carbide core drills can be used, but diamond is more successful when cutting through rebar. The earliest core drills were those used by the ancient Egyptians, invented in 3000 BC. Core drills are used for many applications, either where the core needs to be preserved (the drilling apparatus used in obtaining a core sample is often referred to as a corer), or where drilling can be done more rapidly since much less material needs to be removed than with a standard bit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thebes, Egypt
, image = Decorated pillars of the temple at Karnac, Thebes, Egypt. Co Wellcome V0049316.jpg , alt = , caption = Pillars of the Great Hypostyle Hall, in ''The Holy Land, Syria, Idumea, Arabia, Egypt, and Nubia'' , map_type = Egypt , map_alt = , map_size = , relief = yes , coordinates = , location = Luxor, Luxor Governorate, Egypt , region = Upper Egypt , type = Settlement , part_of = , length = , width = , area = , height = , builder = , material = , built = , abandoned = , epochs = , cultures = , dependency_of = , occupants = , event = , excavations = , archaeologists = , condition = , ownership = , management = , public_access = , website = , notes = , designation1 = WHS , designation1_offname = Ancient Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hieroglyphs
A hieroglyph (Greek for "sacred carvings") was a character of the ancient Egyptian writing system. Logographic scripts that are pictographic in form in a way reminiscent of ancient Egyptian are also sometimes called "hieroglyphs". In Neoplatonism, especially during the Renaissance, a "hieroglyph" was an artistic representation of an esoteric idea, which Neoplatonists believed actual Egyptian hieroglyphs to be. The word ''hieroglyphics'' refers to a hieroglyphic script. The Egyptians invented the pictorial script, which refers to any writing system that employs images as symbols for various semantic entities, rather than the abstract signs used by alphabets. The appearance of these distinctive figures in 3000 BCE marked the beginning of Egyptian civilization. Though based on images, Egyptian script was more than a sophisticated form of picture-writing. Each picture/ glyph served one of three functions: (1) to represent the image of a thing or action, (2) to stand for a sound or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flint
Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Flint was widely used historically to make stone tools and start fires. It occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones.''The Flints from Portsdown Hill'' Inside the nodule, flint is usually dark grey, black, green, white or brown in colour, and often has a glassy or waxy appearance. A thin layer on the outside of the nodules is usually different in colour, typically white and rough in texture. The nodules can often be found along s and |
Dentistry
Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the teeth, gums, and mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, disorders, and conditions of the mouth, most commonly focused on dentition (the development and arrangement of teeth) as well as the oral mucosa. Dentistry may also encompass other aspects of the craniofacial complex including the temporomandibular joint. The practitioner is called a dentist. The history of dentistry is almost as ancient as the history of humanity and civilization with the earliest evidence dating from 7000 BC to 5500 BC. Dentistry is thought to have been the first specialization in medicine which have gone on to develop its own accredited degree with its own specializations. Dentistry is often also understood to subsume the now largely defunct medical specialty of stomatology (the study of the mouth and its disorders and diseases) for which reas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indus Valley Civilisation
The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900 BCE. Together with ancient Egypt and Mesopotamia, it was one of three early civilisations of the Near East and South Asia, and of the three, the most widespread. Its sites spanned an area from much of Pakistan, to northeast Afghanistan, and northwestern India. The civilisation flourished both in the alluvial plain of the Indus River, which flows through the length of Pakistan, and along a system of perennial monsoon-fed rivers that once coursed in the vicinity of the Ghaggar-Hakra River, Ghaggar-Hakra, a seasonal river in northwest India and eastern Pakistan. The term ''Harappan'' is sometimes applied to the Indus civilisation after its type site Harappa, the first to be excavated early in the 20th century in what was then the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mehrgarh
Mehrgarh (; ur, ) is a Neolithic archaeological site (dated ) situated on the Kacchi Plain of Balochistan in Pakistan. It is located near the Bolan Pass, to the west of the Indus River and between the modern-day Pakistani cities of Quetta, Kalat and Sibi. The site was discovered in 1974 by an archaeological team led by the French archaeologists Jean-François Jarrige and his wife, Catherine Jarrige. Mehrgarh was excavated continuously between 1974 and 1986, and again from 1997 to 2000. Archaeological material has been found in six mounds, and about 32,000 artifacts have been collected from the site. The earliest settlement at Mehrgarh—located in the northeast corner of the site—was a small farming village dated between 7000 BCE and 5500 BCE. History Mehrgarh is one of the earliest known sites that shows evidence of farming and herding in South Asia.UNESCO World Heritage. 2004. ''Archaeological Site of Mehrgarh''Hirst, K. Kris. 2005"Mehrgarh". '' Guide to Archaeology'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
