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Marcus Hook Range Rear Light
Marcus Hook Range Rear Light is a lighthouse near Bellefonte, Delaware marking a range on the Delaware River. It is the highest light on the Atlantic coast of the United States."The rear range light of Marcus Hook on the Delaware River, 278 feet above the level of the sea, is the highest light on the Atlantic Coast of the continental United States." The lighthouse is visible on the horizon from the windows of high-rise buildings in downtown Wilmington, Delaware. History The permanent structure was preceded by a temporary light on a post, erected in 1915. The present tower was built in 1918 and was composed of nine sections of reinforced concrete; there is also an oil house and a keeper's dwelling on the site. The original beacon displayed a fixed white light using a Fourth order Fresnel lens; this was removed in the early 1980s and replaced with a RL-24 beacon, displaying a fixed red indication. The light was automated in the 1950s, but the keeper's house was occupied by Coast Gua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bellefonte, Delaware
Bellefonte is a town in New Castle County, Delaware, United States. According to the 2020 Census, the population of the town is 1,225. Geography Bellefonte is located at (39.7662246, –75.5093647). The town is roughly centered at the intersection of Brandywine Boulevard and Bellefonte Avenue. According to the United States Census Bureau, the town has a total area of , all land. Climate The climate in this area is characterized by hot, humid summers and generally mild to cool winters. According to the Köppen Climate Classification system, Bellefonte has a humid subtropical climate, abbreviated "Cfa" on climate maps. Infrastructure Transportation Brandywine Boulevard serves as the main street through Bellefonte, passing southwest-northeast through the town. U.S. Route 13 Business (Philadelphia Pike) passes along the northwestern edge of Bellefonte, heading northeast to Claymont and southwest to Wilmington. Delaware Route 3 passes to the west of Bellefonte and provides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete
Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactured material in the world. When aggregate is mixed with dry Portland cement and water, the mixture forms a fluid slurry that can be poured and molded into shape. The cement reacts with the water through a process called hydration, which hardens it after several hours to form a solid matrix that binds the materials together into a durable stone-like material with various uses. This time allows concrete to not only be cast in forms, but also to have a variety of tooled processes performed. The hydration process is exothermic, which means that ambient temperature plays a significant role in how long it takes concrete to set. Often, additives (such as pozzolans or superplasticizers) are included in the mixture to improve the physical prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reinforced Concrete
Reinforced concrete, also called ferroconcrete or ferro-concrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel reinforcing bars (known as rebar) and is usually embedded passively in the concrete before the concrete sets. However, post-tensioning is also employed as a technique to reinforce the concrete. In terms of volume used annually, it is one of the most common engineering materials. In corrosion engineering terms, when designed correctly, the alkalinity of the concrete protects the steel rebar from corrosion. Description Reinforcing schemes are generally designed to resist tensile stresses in particular regions of the concrete that might cause unacceptable cracking and/or structural failure. Modern reinforced concrete can contain varied reinforcing materials made o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fresnel Lens
A Fresnel lens ( ; ; or ) is a type of composite compact lens (optics), lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections. The simpler Dioptrics, dioptric (purely refraction, refractive) form of the lens was first proposed by Georges-Louis Leclerc, Comte de Buffon, and independently reinvented by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. The Catadioptric system, catadioptric (combining refraction and reflection) form of the lens, entirely invented by Fresnel, has outer Prism (optics), prismatic elements that use total internal reflection as well as refraction to capture more oblique light from the light source and add it to the beam, making it visible at greater distances. The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colonial Revival
The Colonial Revival architectural style seeks to revive elements of American colonial architecture. The beginnings of the Colonial Revival style are often attributed to the Centennial Exhibition of 1876, which reawakened Americans to the architectural traditions of their colonial past. Fairly small numbers of Colonial Revival homes were built –1910, a period when Queen Anne-style architecture was dominant in the United States. From 1910–1930, the Colonial Revival movement was ascendant, with about 40% of U.S. homes built in the Colonial Revival style. In the immediate post-war period (–early 1960s), Colonial Revival homes continued to be constructed, but in simplified form. In the present day, many New Traditional homes draw from Colonial Revival styles. Although associated with the architectural movement, "Colonial Revival" also refers to historic preservation, landscape architecture and garden design, and decorative arts movements that emulate or draw i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouse
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] |
Leading Lights
Leading lights, also known as range lights in the United States, are a pair of light beacons used in navigation to indicate a safe passage for vessels entering a shallow or dangerous channel; they may also be used for position fixing. At night, the lights are a form of leading line that can be used for safe navigation. The beacons consist of two lights that are separated in distance and elevation, so that when they are aligned, with one above the other, they provide a bearing. Range lights are often illuminated day and night. In some cases the two beacons are unlighted, in which case they are known as a ''range'' in the United States or a '' transit'' in the UK. The beacons may be artificial or natural. Operation Two lights are positioned near one another. One, called the front light, is lower than the one behind, which is called the rear light. At night when viewed from a ship, the two lights only become aligned vertically when a vessel is positioned on the correct bearing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delaware River
The Delaware River is a major river in the Mid-Atlantic region of the United States and is the longest free-flowing (undammed) river in the Eastern United States. From the meeting of its branches in Hancock, New York, the river flows for along the borders of New York, Pennsylvania, New Jersey, and Delaware, before emptying into Delaware Bay. The river has been recognized by the National Wildlife Federation as one of the country's Great Waters and has been called the "Lifeblood of the Northeast" by American Rivers. Its watershed drains an area of and provides drinking water for 17 million people, including half of New York City via the Delaware Aqueduct. The Delaware River has two branches that rise in the Catskill Mountains of New York: the West Branch at Mount Jefferson in Jefferson, Schoharie County, and the East Branch at Grand Gorge, Delaware County. The branches merge to form the main Delaware River at Hancock, New York. Flowing south, the river re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Ocean
The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for separating the New World of the Americas (North America and South America) from the Old World of Afro-Eurasia (Africa, Asia, and Europe). Through its separation of Afro-Eurasia from the Americas, the Atlantic Ocean has played a central role in the development of human society, globalization, and the histories of many nations. While the Norse colonization of North America, Norse were the first known humans to cross the Atlantic, it was the expedition of Christopher Columbus in 1492 that proved to be the most consequential. Columbus's expedition ushered in an Age of Discovery, age of exploration and colonization of the Americas by European powers, most notably Portuguese Empire, Portugal, Spanish Empire, Sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilmington, Delaware
Wilmington is the List of municipalities in Delaware, most populous city in the U.S. state of Delaware. The city was built on the site of Fort Christina, the first Swedish colonization of the Americas, Swedish settlement in North America. It lies at the confluence of the Christina River and Brandywine Creek (Christina River tributary), Brandywine Creek, near where the Christina flows into the Delaware River. It is the county seat of New Castle County, Delaware, New Castle County and one of the major cities in the Delaware Valley metropolitan area. Wilmington was named by Proprietor Thomas Penn after his friend Spencer Compton, 1st Earl of Wilmington, who was Prime Minister of the United Kingdom, prime minister during the reign of George II of Great Britain. As of the 2020 United States census, 2020 census, the city's population was 70,898. Wilmington is part of the Delaware Valley metropolitan statistical area (which also includes Philadelphia, Reading, Pennsylvania, Reading, Cam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Historic Lighthouse Preservation Act
The National Historic Lighthouse Preservation Act of 2000 (NHLPA; Public Law 106-355; 16 U.S.C. 470w-7) is United States, American legislation creating a process for the transfer of federally owned lighthouses into private hands. It was created as an extension of the National Historic Preservation Act of 1966. Background Maintenance of aid to navigation, aids to navigation had been assigned to the federal government from the beginning, first under the Department of the Treasury, and then under the U.S. Lighthouse Board (1852-1910) and its successor, the U.S. Lighthouse Service. In 1939 lighthouses were placed under the authority of the United States Coast Guard, which also took over the manning of lights with keepers. Throughout this period the expense of maintaining and staffing lights was constantly stressed. Automation of lights began early in the twentieth century, and a major push in the early 1960s relieved all but a few lighthouses of their keepers. Lighthouses are fairly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouses Completed In 1918
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 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 promontories, unlike many moder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
