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Lighthouses In Queensland
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lens (optics), 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 the advent of much cheaper, more sophisticated, and more 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 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 promontory, prom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NJ LBI Lighthouse 04
New Jersey is a U.S. state, state located in both the Mid-Atlantic States, Mid-Atlantic and Northeastern United States, Northeastern regions of the United States. Located at the geographic hub of the urban area, heavily urbanized Northeast megalopolis, it is bordered to the northwest, north, and northeast by New York (state), New York State; on its east, southeast, and south by the Atlantic Ocean; on its west by the Delaware River and Pennsylvania; and on its southwest by Delaware Bay and Delaware. At , New Jersey is the List of U.S. states and territories by area, fifth-smallest state in land area. According to a 2024 United States Census Bureau, U.S. Census Bureau estimate, it is the List of U.S. states and territories by population, 11th-most populous state, with over 9.5 million residents, its highest estimated count ever. The state capital is Trenton, New Jersey, Trenton, and the state's most populous city is Newark, New Jersey, Newark. New Jersey is the only U.S. stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ostia Antica (archaeological Site)
Ostia Antica () is an ancient Roman city and the port of History of Rome, Rome located at the mouth of the Tiber. It is near modern Ostia (Rome), Ostia, southwest of Rome. Due to siltation, silting and the invasion of sand, the site now lies from the sea. The name ''Ostia'' (the plural of ''ostium'') derives from Latin ''os'' 'mouth'. Ostia is now a large Classical archaeology, archaeological site noted for the excellent preservation of its ancient buildings, magnificent frescoes and impressive mosaics. The city's decline after antiquity led to harbor deterioration, marshy conditions, and reduced population. Sand dunes covering the site aided its preservation. Its remains provide insights into a city of commercial importance. As in Pompeii, Ostia's ruins provide details about Roman urbanism that are not accessible within the city of Rome itself. History Origins Ostia may have been Rome's first ''colonia (Roman), colonia''. According to legend, Ancus Marcius, the fourth kings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Lime
Hydraulic lime (HL) is a general term for a variety of lime different from calcium oxide (quicklime), that sets by hydration and consists of calcium silicate and calcium aluminate, compounds that can harden in contact with water. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
