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Fort Point Light (California)
Fort Point Light is a decommissioned lighthouse built on the third tier of Fort Point, which is now directly beneath the south anchorage of the Golden Gate Bridge in San Francisco, California. The lighthouse is at the south end of the narrowest part of Golden Gate strait. It was preceded by two other lighthouses in nearby locations. The present lighthouse was in operation from 1864 until 1934. Structures There have been three lighthouses built in the area where Fort Point stands today. The original lighthouse, built in 1853, was a Cape Cod style lighthouse with an integral tower. It was the second lighthouse to be built on the US west coast, but it stood for only three months, and was never lit. While awaiting the arrival of its lens (from Paris), it was torn down to make room for the Army fort. The second lighthouse at Fort Point was a squat wooden tower with four sides that sloped up to a square watch room. It was built on the narrow ledge between the fort and the water. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden Gate Bridge
The Golden Gate Bridge is a suspension bridge spanning the Golden Gate, the strait connecting San Francisco Bay and the Pacific Ocean. The structure links the U.S. city of San Francisco, California—the northern tip of the San Francisco Peninsula—to Marin County, carrying both U.S. Route 101 and California State Route 1 across the strait. It also carries pedestrian and bicycle traffic, and is designated as part of U.S. Bicycle Route 95. Being declared one of the Wonders of the Modern World by the American Society of Civil Engineers, the bridge is one of the most internationally recognized symbols of San Francisco and California. It was initially designed by engineer Joseph Strauss in 1917. The bridge was named for the Golden Gate strait, the channel that it spans. The Frommer's travel guide describes the Golden Gate Bridge as "possibly the most beautiful, certainly the most photographed, bridge in the world." At the time of its opening in 1937, it was both the longe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fresnel Lens
A Fresnel lens ( ; ; or ) is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. It has been called "the invention that saved a million ships." 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 design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. The simpler dioptric (purely refractive) form of the lens was first proposed by Count Buffon and independently reinvented by Fresnel. The ''catadioptric'' form of the lens, entirely invented by Fresnel, has outer elements that use total internal reflection as well as refraction; it can capture more oblique light from a light source and add it to the beam of a lighthouse, making the light visible from greater distances. Description The Fresnel lens redu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Government Buildings On The National Register Of Historic Places In San Francisco
A government is the system or group of people governing an organized community, generally a state. In the case of its broad associative definition, government normally consists of legislature, executive, and judiciary. Government is a means by which organizational policies are enforced, as well as a mechanism for determining policy. In many countries, the government has a kind of constitution, a statement of its governing principles and philosophy. While all types of organizations have governance, the term ''government'' is often used more specifically to refer to the approximately 200 independent national governments and subsidiary organizations. The major types of political systems in the modern era are democracies, monarchies, and authoritarian and totalitarian regimes. Historically prevalent forms of government include monarchy, aristocracy, timocracy, oligarchy, democracy, theocracy, and tyranny. These forms are not always mutually exclusive, and mixed govern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouses On The National Register Of Historic Places In California
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 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouses Completed In 1853
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] |
List Of Lighthouses In The United States
This is a list of lighthouses in the United States. The United States has had approximately a thousand lights as well as light towers, range lights, and pier head lights. Michigan has the most lights of any state with over 150 past and present lights. Lighthouses that are in former U.S. territories are not listed here. Most of the lights in the United States have been built and maintained by the Coast Guard (since 1939) and its predecessors, the United States Lighthouse Service (1910–1939) and the United States Lighthouse Board (1852–1910). Before the Lighthouse Board was established, local collectors of customs were responsible for lighthouses under Stephen Pleasonton. As their importance to navigation has declined and as public interest in them has increased, the Coast Guard has been handing over ownership and in some cases responsibility for running them to other parties, the chief of them being the National Park Service under the National Historic Lighthouse Preservation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Rankin (lighthouse Keeper)
James Rankin (February 20, 1844 – January 5, 1921) was a lighthouse keeper in the United States. A native of Killashee, County Longford, Ireland, Rankin emigrated to the United States in 1867. He served in the U.S. Lighthouse Service as the keeper of East Brother Island Light in California from 1877 to 1878. He then transferred to Fort Point Light in San Francisco, where he remained for 40 years, until retiring in 1919. During his tenure he was credited with saving the lives of 18 people. Rankin died in Antioch, California, where he had moved soon after retiring. In 1997, the United States Coast Guard named a buoy tender USCGC ''James Rankin'' (WLM-555) in his honor. Its homeport is Curtis Bay, Baltimore Curtis Bay is a residential / commercial / industrial neighborhood in the southern portion of the City of Baltimore, Maryland, United States. The neighborhood is on steep sloping heights, about four city blocks wide (west to east) and fifteen bloc .... References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, clause 1 of the United States Constitution (1789). See alsTitle 10, Subtitle B, Chapter 301, Section 3001 The oldest and most senior branch of the U.S. military in order of precedence, the modern U.S. Army has its roots in the Continental Army, which was formed 14 June 1775 to fight the American Revolutionary War (1775–1783)—before the United States was established as a country. After the Revolutionary War, the Congress of the Confederation created the United States Army on 3 June 1784 to replace the disbanded Continental Army.Library of CongressJournals of the Continental Congress, Volume 27/ref> The United States Army considers itself to be a continuation of the Continental Army, and thus considers its institutional inception to be th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Francisco
San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the List of California cities by population, fourth most populous in California and List of United States cities by population, 17th most populous in the United States, with 815,201 residents as of 2021. It covers a land area of , at the end of the San Francisco Peninsula, making it the second most densely populated large U.S. city after New York City, and the County statistics of the United States, fifth most densely populated U.S. county, behind only four of the five New York City boroughs. Among the 91 U.S. cities proper with over 250,000 residents, San Francisco was ranked first by per capita income (at $160,749) and sixth by aggregate income as of 2021. Colloquial nicknames for San Francisco include ''SF'', ''San Fran'', ''The '', ''Frisco'', and '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paris
Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Since the 17th century, Paris has been one of the world's major centres of finance, diplomacy, commerce, fashion, gastronomy, and science. For its leading role in the arts and sciences, as well as its very early system of street lighting, in the 19th century it became known as "the City of Light". Like London, prior to the Second World War, it was also sometimes called the capital of the world. The City of Paris is the centre of the Île-de-France region, or Paris Region, with an estimated population of 12,262,544 in 2019, or about 19% of the population of France, making the region France's primate city. The Paris Region had a GDP of €739 billion ($743 billion) in 2019, which is the highest in Europe. According to the Economist Intelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden Gate
The Golden Gate is a strait on the west coast of North America that connects San Francisco Bay to the Pacific Ocean. It is defined by the headlands of the San Francisco Peninsula and the Marin Peninsula, and, since 1937, has been spanned by the Golden Gate Bridge. The entire shoreline and adjacent waters throughout the strait are managed by the Golden Gate National Recreation Area. Geology During the last ice age, when sea level was several hundred feet lower, the waters of the glacier-fed Sacramento River and the San Joaquin River scoured a deep channel through the bedrock on their way to the ocean. (A similar process created the undersea Hudson Canyon off the coast of New York and New Jersey.) The strait is well known today for its depth and powerful tidal currents from the Pacific Ocean. Many small whirlpools and eddies can form in its waters. With its strong currents, rocky reefs and fog, the Golden Gate is the site of over 100 shipwrecks. Climate The Golden Gat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
