|
Cape Ann Light
The Cape Ann Light Station on Thacher Island, off Cape Ann in Rockport, Massachusetts, is nationally significant as the last light station to be established under colonial rule and the first station in the United States to mark a navigational hazard rather than a harbor entrance. The current pair of lighthouses were built in 1861. They were both equipped with first order Fresnel lenses, which stood approximately high and weighed several tons (tonnes). After being decommissioned in the early 1980s, the lens from the south tower was moved to the U.S. Coast Guard Museum at the United States Coast Guard Academy in New London, Connecticut. In 2013 a joint effort by the Cape Ann Museum and the Thacher Island Association brought the lens back to Cape Ann. The first order lens is now on display at the Cape Ann Museum in Gloucester, Massachusetts. When these lights were built, there was no way to produce a flashing light and, occasionally mariners would confuse one light for another ... [...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] |
Thacher Island Lighthouses In 2009
Thacher may refer to: People * Ebby Thacher (1896–1966), early member of the sobriety movement that later became Alcoholics Anonymous *George Thacher (1817–1878), an American academic *James Thacher (1754–1844), an American physician *Jeff Thacher (born 1967), an American musician **James Kingsley Thacher (1847–1891), his son, an American professor of medicine *John Boyd Thacher (1847–1909), mayor of Albany, New York, like his father George Thacher **John Boyd Thacher II, his nephew, mayor of Albany, New York * Nicholas G. Thacher (1915–2002), an American diplomat *Peter Thacher (1752–1802), a n American congregationalist minister *Russell Thacher (c. 1919 – 1990), an American author and film producer * Ryan Thacher (born 1989), an American tennis player *Samuel Cooper Thacher (1785–1818), an American clergyman and librarian *Solon O. Thacher (1830-1895), American politician, judge, and lawyer *Thomas Thacher (minister) (1620–1678), English clergyman and settle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Register Of Historic Places In Essex County, Massachusetts
This list is of that portion of the National Register of Historic Places (NRHP) designated in Essex County, Massachusetts. The locations of these properties and districts for which the latitude and longitude coordinates are included below, may be seen in a map. There are more than 450 designated properties in the county, including 26 that are further designated as National Historic Landmarks. The municipalities of Andover, Gloucester, Ipswich, Lawrence, Lynn, Methuen, and Salem are to be found on a separate list(s) of the more than 200 identified here, except two properties are split between Methuen and Lawrence, and one between Lynn and Nahant; these entries appear on more than one list. __NOTOC__ Cities and towns listed separately Due to the number of listings in the county, some cities and towns have their sites listed separately. Current listings in other cities and towns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouses In Essex County, Massachusetts
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] |
National Historic Landmark Lighthouses
National may refer to: Common uses * Nation or country ** Nationality – a ''national'' is a person who is subject to a nation, regardless of whether the person has full rights as a citizen Places in the United States * National, Maryland, census-designated place * National, Nevada, ghost town * National, Utah, ghost town * National, West Virginia, unincorporated community Commerce * National (brand), a brand name of electronic goods from Panasonic * National Benzole (or simply known as National), former petrol station chain in the UK, merged with BP * National Car Rental, an American rental car company * National Energy Systems, a former name of Eco Marine Power * National Entertainment Commission, a former name of the Media Rating Council * National Motor Vehicle Company, Indianapolis, Indiana, USA 1900-1924 * National Supermarkets, a defunct American grocery store chain * National String Instrument Corporation, a guitar company formed to manufacture the first resonator gui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Historic Landmarks In Massachusetts
The Commonwealth of Massachusetts has a total of 191 National Historic Landmarks (NHLs) within its borders. This is the second highest statewide total in the United States after New York, which has more than 250. Of the Massachusetts NHLs, 57 are in the state capital of Boston, and are listed separately. Ten of the remaining 134 designations were made when the NHL program was formally inaugurated on October 9, 1960; the most recent were in 2021. Cambridge is the city with the most NHLs outside Boston (at 19), and Middlesex County is home to 43 NHLs (again outside the 58 from Boston, which comprise all but two of the NHLs in Suffolk County). Every county in the state has at least one NHL ( Franklin County has exactly one, the Old Deerfield Historic District). The state's NHLs were chosen for a diversity of reasons. Some of the nation's oldest surviving structures are included: a number of 17th-century houses are listed, including the Fairbanks House (late 1630s) of Dedha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouses On The National Register Of Historic Places In Massachusetts
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 Completed In 1861
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] |
Towers Completed In 1771
A tower is a tall structure, taller than it is wide, often by a significant factor. Towers are distinguished from masts by their lack of guy-wires and are therefore, along with tall buildings, self-supporting structures. Towers are specifically distinguished from buildings in that they are built not to be habitable but to serve other functions using the height of the tower. For example, the height of a clock tower improves the visibility of the clock, and the height of a tower in a fortified building such as a castle increases the visibility of the surroundings for defensive purposes. Towers may also be built for observation, leisure, or telecommunication purposes. A tower can stand alone or be supported by adjacent buildings, or it may be a feature on top of a larger structure or building. Etymology Old English ''torr'' is from Latin ''turris'' via Old French ''tor''. The Latin term together with Greek τύρσις was loaned from a pre-Indo-European Mediterranean language, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouses Completed In 1771
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 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Register Of Historic Places Listings In Essex County, Massachusetts
This list is of that portion of the National Register of Historic Places (NRHP) designated in Essex County, Massachusetts. The locations of these properties and districts for which the latitude and longitude coordinates are included below, may be seen in a map. There are more than 450 designated properties in the county, including 26 that are further designated as National Historic Landmarks. The municipalities of Andover, Gloucester, Ipswich, Lawrence, Lynn, Methuen, and Salem are to be found on a separate list(s) of the more than 200 identified here, except two properties are split between Methuen and Lawrence, and one between Lynn and Nahant; these entries appear on more than one list. __NOTOC__ Cities and towns listed separately Due to the number of listings in the county, some cities and towns have their sites listed separately. Current listings in other cities and towns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Historic Landmark
A National Historic Landmark (NHL) is a building, district, object, site, or structure that is officially recognized by the United States government for its outstanding historical significance. Only some 2,500 (~3%) of over 90,000 places listed on the country's National Register of Historic Places are recognized as National Historic Landmarks. A National Historic Landmark District may include contributing properties that are buildings, structures, sites or objects, and it may include non-contributing properties. Contributing properties may or may not also be separately listed. Creation of the program Prior to 1935, efforts to preserve cultural heritage of national importance were made by piecemeal efforts of the United States Congress. In 1935, Congress passed the Historic Sites Act, which authorized the Interior Secretary authority to formally record and organize historic properties, and to designate properties as having "national historical significance", and gave the Nation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
