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Lincoln Rock Light in southeastern Alaska, United States. It lay just off the west coast of Etolin Island, between it and Prince of Wales Island.
The Lincoln Rock Lighthouse was a lighthouse located on Lincoln Island, a small islet in Clarence Strait Clarence Strait, originally Duke of Clarence Strait, History The original lighthouse was built in 1903 and was abandoned in 1909 after being damaged by a storm. In 1911 a manned fog signal station was built ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarence Strait
Clarence Strait, originally Duke of Clarence Strait, , Alexander Begg, Victoria, British Columbia, publ. R. Wolfenden, 1902] is a in , in the |
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., it borders the Canadian province of British Columbia and the Yukon territory to the east; it also shares a maritime border with the Russian Federation's Chukotka Autonomous Okrug to the west, just across the Bering Strait. To the north are the Chukchi and Beaufort Seas of the Arctic Ocean, while the Pacific Ocean lies to the south and southwest. Alaska is by far the largest U.S. state by area, comprising more total area than the next three largest states (Texas, California, and Montana) combined. It represents the seventh-largest subnational division in the world. It is the third-least populous and the most sparsely populated state, but by far the continent's most populous territory located mostly north of the 60th parallel, with ... [...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] |
Lighthouse
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] |
Alaska Panhandle
Southeast Alaska, colloquially referred to as the Alaska(n) Panhandle, is the southeastern portion of the U.S. state of Alaska, bordered to the east and north by the northern half of the Canadian province of British Columbia (and a small part the Yukon Territories). The majority of Southeast Alaska's area is part of the Tongass National Forest, the United States' largest national forest. In many places, the international border runs along the crest of the Boundary Ranges of the Coast Mountains (see Alaska boundary dispute). The region is noted for its scenery and mild, rainy climate. The largest cities in the region are Juneau, Sitka, and Ketchikan. This region is also home to Hyder, the easternmost town in Alaska. Geography Southeast Alaska has a land area of , comprising much of the Alexander Archipelago. The largest islands are, from North to South, Chichagof Island, Admiralty Island, Baranof Island, Kupreanof Island, Revillagigedo Island and Prince of Wales Island. Maj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etolin Island
Etolin Island is an island in the Alexander Archipelago of southeastern Alaska, United States at . It is between Prince of Wales Island, to its west, and the Alaska mainland, to its east. It is southwest of Wrangell Island. It was first charted in 1793 by James Johnstone, one of George Vancouver's officers during his 1791-95 expedition. He only charted its southwest and east coasts, not realizing it was an island. It was originally named Duke of York Island but was renamed by the United States after the Alaska Purchase. , Alexander Begg, Report to the |
Prince Of Wales Island (Alaska)
Prince of Wales Island (Tlingit: ''Taan'') is one of the islands of the Alexander Archipelago in the Alaska Panhandle. It is the fourth-largest island in the United States (after Hawaii, Kodiak Island, and Puerto Rico) and the 97th-largest island in the world. Geography and ecology The island is long, wide and has an area of , about one-tenth the size of Ireland and slightly larger than the state of Delaware. Approximately 6,000 people live on the island. Craig is the largest community; founded as a saltery in the early 20th century, it has a population of 1,500. Some 900 people live in Klawock, a long-established village that grew with the fishing industry. Hollis was a boom and bust mining town from 1900 to about 1915. Abandoned, it was re-established as a logging camp in the 1950s. It now has a population of 100 and is the location of the ferry terminal. Mountain peaks, all but the tallest of which were buried by Pleistocene glaciation, reach over . Fjords, steep-si ... [...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] |
Lighthouses Completed In 1903
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] |
Lighthouses In Alaska
This is a list of all lighthouses in the U.S. state of Alaska as identified by the United States Coast Guard. There are eleven active lights in the state; the other five have been replaced by automated skeleton towers. The history of Alaskan lighthouses predates the Alaska Purchase, Seward purchase: the Russians erected a light at Sitka, Alaska, Sitka, in Baranof Castle (located on Castle Hill (Sitka, Alaska), Castle Hill); this light was found unnecessary by the Lighthouse Service and discontinued, but was taken over by the army and maintained by them until 1877. The first American lighthouses in the state were erected in 1902 but most early lights were rebuilt before 1940 in a distinctive Art Deco style; the only surviving building from the earlier group is the Eldred Rock Light. The last constructed were replacements for the lights on Unimak Island in 1950. Alaska has the northernmost and westernmost lighthouses in the United States, and some of the most isolated as well. Keepe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
