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Lighthouses In Victoria (Australia)
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and has become uneconomical since the advent of much cheaper, more sophisticated and effective electronic navigational systems. History Ancient lighthouses Before the development of clearly defined ports, mariners were guided by fires built on hilltops. Since elevating the fire would improve the visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aveiro March 2012-13
Aveiro may refer to: * Aveiro, Pará, a municipality in Brazil * Aveiro, Portugal, a city and municipality in Portugal ** Região de Aveiro, surrounding the city above ** Aveiro District, surrounding the municipality above ** Roman Catholic Diocese of Aveiro, surrounding the city above ** Aveiro Lagoon (Ria de Aveiro), near the city above *** Aveiro Light, at the entrance to the lagoon above People * Dukes of Aveiro, an aristocratic Portuguese title, granted in 1535 * Cristiano Ronaldo dos Santos Aveiro (born 1985), Portuguese footballer * Kátia Aveiro (born 1977), Portuguese singer * José Aveiro (born 1936), Paraguayan footballer {{disambiguation, geo, surname Portuguese-language surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ostia Antica (archaeological Site)
Ostia Antica ("Ancient Ostia") is a large archaeological site, close to the modern town of Ostia, that is the location of the harbour city of ancient Rome, 25 kilometres (15 miles) southwest of Rome. "Ostia" (plur. of "ostium") is a derivation of "os", the Latin word for "mouth". At the mouth of the River Tiber, Ostia was Rome's seaport, but due to silting the site now lies from the sea. The site is noted for the excellent preservation of its ancient buildings, magnificent frescoes and impressive mosaics. History Origins Ostia may have been Rome's first '' colonia''. According to legend, Ancus Marcius, the fourth king of Rome, was the first to destroy Ficana, an ancient town that was only from Rome and had a small harbour on the Tiber, and then proceeded with establishing the new colony further west and closer to the sea coast. An inscription seems to confirm the establishment of the old ''castrum'' of Ostia in the 7th century BC. The oldest archaeological remains so far ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dowels
A dowel is a cylindrical rod, usually made of wood, plastic, or metal. In its original manufactured form, a dowel is called a ''dowel rod''. Dowel rods are often cut into short lengths called dowel pins. Dowels are commonly used as structural reinforcements in cabinet making and in numerous other applications, including: * Furniture shelf supports * Moveable game pieces (i.e. pegs) * Hangers for items such as clothing, key rings, and tools * Wheel axles in toys * Detents in gymnastics grips * Supports for tiered wedding cakes Wood dowel Manufacturing process The traditional tool for making dowels is a ''dowel plate'', an iron (or better, hardened tool steel) plate with a hole having the size of the desired dowel. To make a dowel, a piece of wood is split or whittled to a size slightly bigger than desired and then driven through the hole in the dowel plate. The sharp edges of the hole shear off the excess wood.Ivin SickelsExercises in Wood-Working American Book Company, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dovetail Joint
A dovetail joint or simply dovetail is a joinery technique most commonly used in woodworking joinery (carpentry), including furniture, cabinets, log buildings, and traditional timber framing. Noted for its resistance to being pulled apart ( tensile strength), the dovetail joint is commonly used to join the sides of a drawer to the front. A series of 'pins' cut to extend from the end of one board interlock with a series of 'tails' cut into the end of another board. The pins and tails have a trapezoidal shape. Once glued, a wooden dovetail joint requires no mechanical fasteners. History The dovetail joint technique probably pre-dates written history. Some of the earliest known examples of the dovetail joint are in ancient Egyptian furniture entombed with mummies dating from First Dynasty, the tombs of Chinese emperors, and a stone pillar at the Vazhappally Maha Siva Temple in India. The dovetail design is an important method of distinguishing various periods of furniture. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Lime
Hydraulic lime (HL) is a general term for calcium oxide, a variety of lime also called quicklime, that sets by hydration. This contrasts with calcium hydroxide, also called slaked lime or air lime that is used to make lime mortar, the other common type of lime mortar, which sets by carbonation (re-absorbing carbon dioxide (CO2) from the air). Hydraulic lime provides a faster initial set and higher compressive strength than air lime, and hydraulic lime will set in more extreme conditions, including under water. The terms 'hydraulic lime' and 'hydrated lime' are quite similar and may be confused but are not necessarily the same material. Hydrated lime is any lime which has been slaked whether it sets through hydration, carbonation, or both. Calcium reacts in the lime kiln with the clay minerals to produce silicates that enable some of the lime to set through hydration. Any unreacted calcium is slaked to calcium hydroxide which sets through carbonation. These are sometimes called ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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