Philadelphia, sometimes known colloquially as Philly, is the largest city in the U. S. state and Commonwealth of Pennsylvania, the sixth-most populous U. S. city, with a 2017 census-estimated population of 1,580,863. Since 1854, the city has been coterminous with Philadelphia County, the most populous county in Pennsylvania and the urban core of the eighth-largest U. S. metropolitan statistical area, with over 6 million residents as of 2017. Philadelphia is the economic and cultural anchor of the greater Delaware Valley, located along the lower Delaware and Schuylkill Rivers, within the Northeast megalopolis; the Delaware Valley's population of 7.2 million ranks it as the eighth-largest combined statistical area in the United States. William Penn, an English Quaker, founded the city in 1682 to serve as capital of the Pennsylvania Colony. Philadelphia played an instrumental role in the American Revolution as a meeting place for the Founding Fathers of the United States, who signed the Declaration of Independence in 1776 at the Second Continental Congress, the Constitution at the Philadelphia Convention of 1787.
Several other key events occurred in Philadelphia during the Revolutionary War including the First Continental Congress, the preservation of the Liberty Bell, the Battle of Germantown, the Siege of Fort Mifflin. Philadelphia was one of the nation's capitals during the revolution, served as temporary U. S. capital while Washington, D. C. was under construction. In the 19th century, Philadelphia became a railroad hub; the city grew from an influx of European immigrants, most of whom came from Ireland and Germany—the three largest reported ancestry groups in the city as of 2015. In the early 20th century, Philadelphia became a prime destination for African Americans during the Great Migration after the Civil War, as well as Puerto Ricans; the city's population doubled from one million to two million people between 1890 and 1950. The Philadelphia area's many universities and colleges make it a top study destination, as the city has evolved into an educational and economic hub. According to the Bureau of Economic Analysis, the Philadelphia area had a gross domestic product of US$445 billion in 2017, the eighth-largest metropolitan economy in the United States.
Philadelphia is the center of economic activity in Pennsylvania and is home to five Fortune 1000 companies. The Philadelphia skyline is expanding, with a market of 81,900 commercial properties in 2016, including several nationally prominent skyscrapers. Philadelphia has more outdoor murals than any other American city. Fairmount Park, when combined with the adjacent Wissahickon Valley Park in the same watershed, is one of the largest contiguous urban park areas in the United States; the city is known for its arts, culture and colonial history, attracting 42 million domestic tourists in 2016 who spent US$6.8 billion, generating an estimated $11 billion in total economic impact in the city and surrounding four counties of Pennsylvania. Philadelphia has emerged as a biotechnology hub. Philadelphia is the birthplace of the United States Marine Corps, is the home of many U. S. firsts, including the first library, medical school, national capital, stock exchange and business school. Philadelphia contains 67 National Historic Landmarks and the World Heritage Site of Independence Hall.
The city became a member of the Organization of World Heritage Cities in 2015, as the first World Heritage City in the United States. Although Philadelphia is undergoing gentrification, the city maintains mitigation strategies to minimize displacement of homeowners in gentrifying neighborhoods. Before Europeans arrived, the Philadelphia area was home to the Lenape Indians in the village of Shackamaxon; the Lenape are a Native American tribe and First Nations band government. They are called Delaware Indians, their historical territory was along the Delaware River watershed, western Long Island, the Lower Hudson Valley. Most Lenape were pushed out of their Delaware homeland during the 18th century by expanding European colonies, exacerbated by losses from intertribal conflicts. Lenape communities were weakened by newly introduced diseases smallpox, violent conflict with Europeans. Iroquois people fought the Lenape. Surviving Lenape moved west into the upper Ohio River basin; the American Revolutionary War and United States' independence pushed them further west.
In the 1860s, the United States government sent most Lenape remaining in the eastern United States to the Indian Territory under the Indian removal policy. In the 21st century, most Lenape reside in Oklahoma, with some communities living in Wisconsin, in their traditional homelands. Europeans came to the Delaware Valley in the early 17th century, with the first settlements founded by the Dutch, who in 1623 built Fort Nassau on the Delaware River opposite the Schuylkill River in what is now Brooklawn, New Jersey; the Dutch considered the entire Delaware River valley to be part of their New Netherland colony. In 1638, Swedish settlers led by renegade Dutch established the colony of New Sweden at Fort Christina and spread out in the valley. In 1644, New Sweden supported the Susquehannocks in their military defeat of the English colony of Maryland. In 1648, the Dutch built Fort Beversreede on the west bank of the Delaware, south of the Schuylkill near the present-day Eastwick neighborhood, to reassert their dominion over the area.
The Swedes responded by building Fort Nya Korsholm, or New Korsholm, named after a town in Finland with a Swedish majority. In 1655, a
The Panama Canal is an artificial 82 km waterway in Panama that connects the Atlantic Ocean with the Pacific Ocean. The canal is a conduit for maritime trade. Canal locks are at each end to lift ships up to Gatun Lake, an artificial lake created to reduce the amount of excavation work required for the canal, 26 m above sea level, lower the ships at the other end; the original locks are 34 m wide. A third, wider lane of locks was constructed between September 2007 and May 2016; the expanded canal began commercial operation on June 26, 2016. The new locks allow transit of larger, post-Panamax ships, capable of handling more cargo. France began work on the canal in 1881, but stopped due to engineering problems and a high worker mortality rate; the United States took over the project in 1904 and opened the canal on August 15, 1914. One of the largest and most difficult engineering projects undertaken, the Panama Canal shortcut reduced the time for ships to travel between the Atlantic and Pacific Oceans, enabling them to avoid the lengthy, hazardous Cape Horn route around the southernmost tip of South America via the Drake Passage or Strait of Magellan.
Colombia and the United States controlled the territory surrounding the canal during construction. The US continued to control the canal and surrounding Panama Canal Zone until the 1977 Torrijos–Carter Treaties provided for handover to Panama. After a period of joint American–Panamanian control, in 1999, the canal was taken over by the Panamanian government, it is now operated by the government-owned Panama Canal Authority. Annual traffic has risen from about 1,000 ships in 1914, when the canal opened, to 14,702 vessels in 2008, for a total of 333.7 million Panama Canal/Universal Measurement System tons. By 2012, more than 815,000 vessels had passed through the canal, it takes 11.38 hours to pass through the Panama Canal. The American Society of Civil Engineers has ranked the Panama Canal one of the seven wonders of the modern world; the earliest mention of a canal across the Isthmus of Panama occurred in 1534, when Charles V, Holy Roman Emperor and King of Spain, ordered a survey for a route through the Americas that would ease the voyage for ships traveling between Spain and Peru.
Such a route would have given the Spanish a military advantage over the Portuguese. In 1668, the English physician and philosopher Sir Thomas Browne speculated in his encyclopaedic endeavour Pseudodoxia Epidemica - "some Isthmus have been eat through by the Sea, others cut by the spade: And if policy would permit, that of Panama in America were most worthy the attempt: it being but few miles over, would open a shorter cut unto the East Indies and China". In 1788, American Thomas Jefferson Minister to France, suggested that the Spanish should build the canal since it would be a less treacherous route for ships than going around the southern tip of South America, that tropical ocean currents would widen the canal thereafter. During an expedition from 1788 to 1793, Alessandro Malaspina outlined plans for its construction. Given the strategic location of Panama and the potential offered by its narrow isthmus separating two great oceans, other trade links in the area were attempted over the years.
The ill-fated Darien scheme was launched by the Kingdom of Scotland in 1698 to set up an overland trade route. Inhospitable conditions thwarted the effort and it was abandoned in April 1700. Numerous canals were built in other countries in the late early 19th centuries; the success of the Erie Canal in the United States in the 1820s and the collapse of the Spanish Empire in Latin America led to a surge of American interest in building an inter-oceanic canal. Beginning in 1826, US officials began negotiations with Gran Colombia, hoping to gain a concession for the building of a canal. Jealous of their newly obtained independence and fearing that they would be dominated by an American presence, the president Simón Bolívar and New Granada officials declined American offers; the new nation was politically unstable, Panama rebelled several times during the 19th century. Another effort was made in 1843. According to the New York Daily Tribune, August 24, 1843, a contract was entered into by Barings of London and the Republic of New Granada for the construction of a canal across the Isthmus of Darien.
They referred to it as the Atlantic and Pacific Canal, it was a wholly British endeavor. It was expected to be completed in five years. At nearly the same time, other ideas were floated, including a canal across Mexico's Isthmus of Tehuantepec. Nothing came of that plan, either. In 1846, the Mallarino–Bidlack Treaty, negotiated between the US and New Granada, granted the United States transit rights and the right to intervene militarily in the isthmus. In 1848, the discovery of gold in California, on the West Coast of the United States, created great interest in a crossing between the Atlantic and Pacific oceans. William H. Aspinwall, the man who won the federal subsidy for the building and operating the Pacific mail steamships at around the same time, benefited from this discovery. Aspinwall's route included steamship legs from New York City to Panama and from Panama to California, with an overland portage through Panama; the route between California and Panama was soon traveled, as it provided one of the fastest links between San Francisco and the East Coast cities, about 40 days' transit in total.
Nearly all the gold, shipped out of California went by the fast Panama route. Several new and larger paddle steamers were soon plying
Pearl Harbor is a lagoon harbor on the island of Oahu, west of Honolulu. It has been long visited by the Naval fleet of the United States, before it was acquired from the Hawaiian Kingdom by the U. S. with the signing of the Reciprocity Treaty of 1875. Much of the harbor and surrounding lands is now a United States Navy deep-water naval base, it is the headquarters of the United States Pacific Fleet. The U. S. government first obtained exclusive use of the inlet and the right to maintain a repair and coaling station for ships here in 1887. The attack on Pearl Harbor by the Empire of Japan on December 7, 1941, was the immediate cause of the United States' entry into World War II. Pearl Harbor was an extensive shallow embayment called Wai Momi or Puʻuloa by the Hawaiians. Puʻuloa was regarded as the home of the shark goddess, Kaʻahupahau, her brother, Kahiʻuka, in Hawaiian legends. According to tradition, the head of the powerful Ewa chiefs, is credited with cutting a navigable channel near the present Puʻuloa saltworks, by which he made the estuary, known as "Pearl River," accessible to navigation.
Making due allowance for legendary amplification, the estuary had an outlet for its waters where the present gap is. During the early 19th century, Pearl Harbor was not used for large ships due to its shallow entrance; the interest of United States in the Hawaiian Islands grew as a result of its whaling and trading activity in the Pacific. As early as 1820, an "Agent of the United States for Commerce and Seamen" was appointed to look after American business in the Port of Honolulu; these commercial ties to the American continent were accompanied by the work of the American Board of Commissioners for Foreign Missions. American missionaries and their families became an integral part of the Hawaiian political body. Throughout the 1820s and 1830s, many American warships visited Honolulu. In most cases, the commanding officers carried letters from the U. S. Government giving advice on governmental affairs and of the relations of the island nation with foreign powers. In 1841, the newspaper Polynesian, printed in Honolulu, advocated that the U.
S. establish a naval base in Hawaii for protection of American citizens engaged in the whaling industry. The British Hawaiian Minister of Foreign Affairs Robert Crichton Wyllie, remarked in 1840 that "... my opinion is that the tide of events rushes on to annexation to the United States." From the conclusion of the Civil War, to the purchase of Alaska, to the increased importance of the Pacific states, the projected trade with countries in Asia and the desire for a duty-free market for Hawaiian staples, Hawaiian trade expanded. In 1865, the North Pacific Squadron was formed to embrace Hawaii. Lackawanna in the following year was assigned to cruise among the islands, "a locality of great and increasing interest and importance." This vessel surveyed the Northwestern Hawaiian Islands toward Japan. As a result, the United States claimed Midway Island; the Secretary of the Navy was able to write in his annual report of 1868, that in November 1867, 42 American flags flew over whaleships and merchant vessels in Honolulu to only six of other nations.
This increased activity caused the permanent assignment of at least one warship to Hawaiian waters. It praised Midway Island as possessing a harbor surpassing Honolulu's. In the following year, Congress approved an appropriation of $50,000 on March 1, 1869, to deepen the approaches to this harbor. After 1868, when the Commander of the Pacific Fleet visited the islands to look after American interests, naval officers played an important role in internal affairs, they served as arbitrators in business disputes, negotiators of trade agreements and defenders of law and order. Periodic voyages among the islands and to the mainland aboard U. S. warships were arranged for members of the Hawaiian royal family and important island government officials. When King Lunalilo died in 1873, negotiations were underway for the cession of Pearl Harbor as a port for the duty-free export of sugar to the U. S. With the election of King Kalākaua in March 1874, riots prompted landing of sailors from USS Tuscarora and Portsmouth.
The British warship, HMS Tenedos landed a token force. During the reign of King Kalākaua the United States was granted exclusive rights to enter Pearl Harbor and to establish "a coaling and repair station." Although this treaty continued in force until August 1898, the U. S. did not fortify Pearl Harbor as a naval base. As it had for 60 years, the shallow entrance constituted a formidable barrier against the use of the deep protected waters of the inner harbor; the United States and the Hawaiian Kingdom signed the Reciprocity Treaty of 1875 as supplemented by Convention on December 6, 1884, the Reciprocity Treaty was made by James Carter and ratified it in 1887. On January 20, 1887, the United States Senate allowed the Navy to exclusive right to maintain a coaling and repair station at Pearl Harbor.. The Spanish–American War of 1898 and the desire for the United States to have a permanent presence in the Pacific both contributed to the decision. Following the overthrow of the Hawaiian Kingdom, the United States Navy established a base on the island in 1899.
On December 7, 1941, the base was attacked by the Imperial Japanese Navy airplanes and midget submarines, causing the American entry into World War II. One of the main reasons that Pearl Harbor happened was because the United States had major communication breakdowns among several branches of the U. S. armed services and departments of the U. S. government. This led to the surprise Japanese attack at the Hawai
Ship commissioning is the act or ceremony of placing a ship in active service, may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most applied to the placing of a warship in active duty with its country's military forces; the ceremonies involved are rooted in centuries old naval tradition. Ship naming and launching endow a ship hull with her identity, but many milestones remain before she is completed and considered ready to be designated a commissioned ship; the engineering plant and electronic systems and multitudinous other equipment required to transform the new hull into an operating and habitable warship are installed and tested. The prospective commanding officer, ship's officers, the petty officers, seamen who will form the crew report for training and intensive familiarization with their new ship. Prior to commissioning, the new ship undergoes sea trials to identify any deficiencies needing correction; the preparation and readiness time between christening-launching and commissioning may be as much as three years for a nuclear powered aircraft carrier to as brief as twenty days for a World War II landing ship.
USS Monitor, of American Civil War fame, was commissioned less than three weeks after launch. Regardless of the type of ship in question, a vessel's journey towards commissioning in its nation's navy begins with a process known as sea trials. Sea trials take place some years after a vessel was laid down, mark the interim step between the completion of a ship's construction and its official acceptance for service with its nation's navy. Sea trials begin when the ship in question is floated out of its dry dock, at which time the initial crew for a ship will assume command of the vessel in question; the ship is sailed in littoral waters for the purpose of testing the design and other ship specific systems to ensure that they work properly and can handle the equipment that they will be using in the coming years. Tests done during this phase can include launching missiles from missile magazines, firing the ship's gun, conducting basic flight tests with rotary and fixed-wing aircraft that will be assigned to the ship in the future, various tests of the electronic and propulsion equipment.
During this phase of testing problems arise relating to the state of the equipment on the ship in question, which can result in the ship returning to the builder's shipyard to address the concerns in question. In addition to problems with a ship's arms and equipment, the sea trial phase a ship undergoes prior to commissioning can identify issues with the ship's design that may need to be addressed before it can be accepted into service with its nation's navy. During her sea trials in 1999 French Naval officials determined that the French aircraft carrier Charles de Gaulle was too short to safely operate the E2C Hawkeye, resulting in her return to the builder's shipyard for enlargement. After a ship has cleared its sea trial period, it will be accepted into service with its nation's navy. At this point, the ship in question will undergo a process of degaussing and/or deperming, which will vastly reduce the ship in question's magnetic signature. Once a ship's sea trials are completed plans for the actual commissioning ceremony will take shape.
Depending on the naval traditions of the nation in question, the commissioning ceremony may be an elaborately planned event with guests, the ship's future crew, other persons of interest in attendance, or the nation in question may forgo a ceremony and instead administratively place the ship in commission. At a minimum, on the day on which the ship in question is to be commissioned the crew will report for duty aboard the ship and the commanding officer will read through the orders given for the ship and its personnel. If the ship's ceremony is a public affair the Captain may make a speech to the audience, along with other VIPs as the ceremony dictates. Religious ceremonies, such as blessing the ship or the singing of traditional hymns or songs, may occur. Once a ship has been commissioned its final step toward becoming an active unit of the navy it now serves is to report to its home port and load or accept any remaining equipment. To decommission a ship is to terminate its career in service in the armed forces of a nation.
Unlike wartime ship losses, in which a vessel lost to enemy action is said to be struck, decommissioning confers that the ship has reached the end of its usable life and is being retired from a given country's navy. Depending on the naval traditions of the country in question, a ceremony commemorating the decommissioning of the ship in question may take place, or the vessel may be removed administratively with little to no fanfare; the term "paid off" is alternatively used in British Commonwealth contexts, originating in the age-of-sail practice of ending an officer's commission and paying crew wages once the ship completed its voyage. Ship decommissioning occurs some years after the ship was commissioned and is intended to serve as a means by which a vessel that has become too old or too obsolete can be retired with honor from the operating country's armed force. Decommissioning of the vessel may occur due to treaty agreements or for safety reasons (such as a ship's nuclear reactor and assoc
Seaman is a military rank used in many navies around the world. It is considered a junior enlisted rank and, depending on the navy, it may be a single rank on its own or a name shared by several similarly-junior ranks. In the Commonwealth, it is the lowest rank in the navy, while in the United States, it refers to the three lowest ranks of the U. S. Navy and U. S. Coast Guard; the equivalent of the seaman is the matelot in French-speaking countries, Matrose in German-speaking countries. The Royal Australian Navy features one Seaman rank. There are 4 grades of seaman/matelot in the Royal Canadian Navy: The rank of master seaman is unique because it was created only for the Canadian Navy, it does not follow the British tradition of other Canadian ranks. It corresponds to the rank of master corporal/caporal-chef. Matelot 2e classe, or apprentice seaman, matelot breveté are designations of the French Navy. Matelots are colloquially known as "mousses". Madrus is the lowest rank in the Estonian Navy, it is equivalent to OR-1 in NATO The German rank of "seaman" is the lowest enlisted rank of the German Navy.
It is equivalent to OR1 in NATO and is a grade A3 in the pay rules of the Federal Ministry of Defence. There is one grade of seaman in the Hellenic Navy. In the Indonesian Navy this rank is referred to as "kelasi". There are three levels of this rank in the Indonesian Navy which are: "seaman recruit", "seaman apprentice", "seaman", the rating system thus mirrors the one used in the US Navy; the Italian rank of "seaman" is the lowest enlisted rank of the Italian Navy equivalent in NATO to OR1. See Military ranks and insignia of the Japan Self-Defense Forces Much Russian military vocabulary was imported, along with military advisers, from Germany in the 16th and 17th centuries; the Russian word for "seaman" or "sailor" was borrowed from the German "matrose". In Imperial Russia the most junior naval rank was "seaman 2nd class"; the 1917 Revolution led to the term "Red Fleet man" until 1943, when the Soviet Navy reintroduced the term "seaman", along with badges of rank. The Russian federation inherited the term in 1991, as did several other former Soviet republics, including Ukraine and Belarus, with Bulgaria using the same word and the same Cyrillic orthography.
Estonia and Latvia use related loanwords. In the Royal Navy the rate is split into two divisions: AB1 and AB2; the AB2 rating is used for those. The rate of ordinary seaman has been discontinued. Seaman is the third enlisted rank from the bottom in the U. S. Navy and U. S. Coast Guard, ranking above seaman apprentice and below petty officer third class; this naval rank was called "seaman first class". The rank is used in United States Naval Sea Cadet Corps, a naval-themed uniformed youth program under the sponsorship of the Navy League of the United States; the actual title for an E-3 in the U. S. Navy varies based on the subset of the Navy or Coast Guard known as a group rate, to which the member will be assigned; the color of their group rate mark depends on that subset of the Navy or Coast Guard in which they are serving and which technical rating they will pursue. Those in the general deck, technical and administrative groups are called "seamen" and they represent the largest group of Navy and Coast Guard personnel in pay grades E-3 and below.
They wear white stripes on their blue uniforms, navy blue stripes on their white uniforms. Those in the medical group are now called "hospitalmen." In October 2005, the USN dental technician rating was merged into the hospital corpsman rating, eliminating the "dentalman" title for E-3 and below. Those who once held the rank of "dentalman" have become "hospitalmen", they wear white stripes on their blue uniforms, navy blue stripes on their white uniforms. After the completion of their "A" school, they wear a caduceus of the same color as the stripes on their uniforms. On their combat uniforms, a hospitalman wears their caduceus on the tab of their left collar tab; this rating was called pharmacist's mate and HMs are colloquially referred to as "corpsman" in the naval service. Hospitalmen exist only in the U. S. Navy. S. Coast Guard is the health services technician, sourced from seamen in that service's administrative and scientific group; those in the shipboard engineering and hull group, comprising conventional and nuclear powerplants and propulsion, as well as the hull maintenance area, are called "firemen."
They wear red stripes on both their USN and USCG blue uniforms and, in the case of the Navy, white uniforms. Those in the aviation group of the Navy and Coast Guard are called "airmen", they wear green stripes on blue uniforms and white uniforms. Enlisted personnel in the construction group, which populates the U. S. Navy's civil engineering construction battalions, are called "constructionmen" and they wear light blue stripes on both their blue and white uniforms. Constructionmen are unique to the U. S. Navy. S. Coast Guard equivalent. No such stripes for E-1, E-2 or E-3 are authorized to be worn on working uniforms, e.g. navy work uniform, USCG operational dress uniform, utility wear, flight suits and clinic garb, diving suits, etc. However, sailors with the pay grade of E-2 o
Anti-submarine warfare is a branch of underwater warfare that uses surface warships, aircraft, or other submarines to find and deter, damage, or destroy enemy submarines. Successful anti-submarine warfare depends on a mix of sensor and weapon technology and experience. Sophisticated sonar equipment for first detecting classifying and tracking the target submarine is a key element of ASW. To destroy submarines, both torpedos and naval mines are used, launched from air and underwater platforms. ASW involves protecting friendly ships; the first attacks on a ship by an underwater vehicle are believed to have been during the American Revolutionary War, using what would now be called a naval mine but what was called a torpedo, though various attempts to build submarines had been made before this. The first self-propelled torpedo was launched from surface craft; the first submarine with a torpedo was Nordenfelt I built in 1884-1885, though it had been proposed earlier. By the outbreak of the Russo-Japanese War all the large navies except the German had acquired submarines.
In 1904 all still defined the submarine as an experimental vessel and did not put it into operational use. There were no means to detect submerged U-boats, attacks on them were limited at first to efforts to damage their periscopes with hammers; the Royal Navy torpedo establishment, HMS Vernon, studied explosive grapnel sweeps. A similar approach featured a string of 70 lb charges on a floating cable, fired electrically. Tried were dropping 18.5 lb hand-thrown guncotton bombs. The Lance Bomb was developed, also. Firing Lyddite shells, or using trench mortars, was tried. Use of nets to ensnare U-boats was examined, as was a destroyer, HMS Starfish, fitted with a spar torpedo. To attack at set depths, aircraft bombs were attached to lanyards. Problems with the lanyards tangling and failing to function led to the development of a chemical pellet trigger as the Type B; these were effective at a distance of around 20 ft. The best concept arose in a 1913 RN Torpedo School report, describing a device intended for countermining, a "dropping mine".
At Admiral John Jellicoe's request, the standard Mark II mine was fitted with a hydrostatic pistol preset for 45 ft firing, to be launched from a stern platform. Weighing 1,150 lb, effective at 100 ft, the "cruiser mine" was a potential hazard to the dropping ship. During the First World War, submarines were a major threat, they operated in North Sea, Black Sea and Mediterranean as well as the North Atlantic. They had been limited to calm and protected waters; the vessels used to combat them were a range of fast surface ships using guns and good luck. They relied on the fact a submarine of the day was on the surface for a range of reasons, such as charging batteries or crossing long distances; the first approach to protect warships was chainlink nets strung from the sides of battleships, as defense against torpedoes. Nets were deployed across the mouth of a harbour or naval base to stop submarines entering or to stop torpedoes of the Whitehead type fired against ships. British warships were fitted with a ram with which to sink submarines, U-15 was thus sunk in August 1914.
RN in June 1915 began operational trials of the Type D depth charge, with a 300 lb charge of TNT and a hydrostatic pistol, firing at either 40 or 80 ft, believed to be effective at a distance of 140 ft. In July 1915, the British Admiralty set up the Board of Invention and Research to evaluate suggestions from the public as well as carrying out their own investigations; some 14,000 suggestions were received about combating submarines. In December 1916, the RN set up its own Anti-Submarine Division but relations with the BIR were poor. After 1917 most ASW work was carried out by ASD. In the U. S. a Naval Consulting Board was set up in 1915 to evaluate ideas. After American entry into the war in 1917, they encouraged work on submarine detection; the U. S. National Research Council, a civilian organization, brought in British and French experts on underwater sound to a meeting with their American counterparts in June 1917. In October 1918, there was a meeting in Paris on "supersonics", a term used for echo-ranging, but the technique was still in research by the end of the war.
The first recorded sinking of a submarine by depth charge was U-68, sunk by Q-ship HMS Farnborough off Kerry, Ireland 22 March 1916. By early 1917, the Royal Navy had developed indicator loops which consisted of long lengths of cables lain on the seabed to detect the magnetic field of submarines as they passed overhead. At this stage they were used in conjunction with controlled mines which could be detonated from a shore station once a'swing' had been detected on the indicator loop galvanometer. Indicator loops used with controlled mining were known as'guard loops'. By July 1917, depth charges had developed to the extent that settings of between 50–200 ft were possible; this design would remain unchanged through
Minneapolis is the county seat of Hennepin County and the larger of the Twin Cities, the 16th-largest metropolitan area in the United States. As of 2017, Minneapolis is the largest city in the state of Minnesota and 45th-largest in the United States, with an estimated population of 422,331; the Twin Cities metropolitan area consists of Minneapolis, its neighbor Saint Paul, suburbs which altogether contain about 3.6 million people, is the third-largest economic center in the Midwest. Minneapolis lies on both banks of the Mississippi River, just north of the river's confluence with the Minnesota River, adjoins Saint Paul, the state's capital; the city is abundantly rich in water, with 13 lakes, the Mississippi River and waterfalls. It was once a hub for timber; the city and surrounding region is the primary business center between Seattle. In 2011, Minneapolis proper was home to the fifth-highest number of Fortune 500 headquarters in the United States; as an integral link to the global economy, Minneapolis is categorized as a global city.
Minneapolis has one of the largest LGBT populations in the U. S. proportional to its overall population. Noted for its strong music and performing arts scenes, Minneapolis is home to both the award-winning Guthrie Theater and the historic First Avenue nightclub. Reflecting the region's status as an epicenter of folk and alternative rock music, the city served as the launching pad for several of the 20th century's most influential musicians, including Bob Dylan and Prince. Minneapolis has become noted for its underground and independent hip-hop and rap scenes, producing artists such as Brother Ali and Dessa; the name Minneapolis is attributed to Charles Hoag, the city's first schoolmaster, who combined mni, a Dakota Sioux word for water, polis, the Greek word for city. Descendants of first peoples, Dakota Sioux were the region's sole residents when French explorers arrived in 1680. For a time, amicable relations were based on fur trading. More European-American settlers arrived, competing for game and other resources with the Native Americans.
After the Revolutionary War, Great Britain granted the land east of the Mississippi to the United States. In the early 19th century, the United States acquired land to the west from France in the Louisiana Purchase. Fort Snelling, just south of present-day Minneapolis, was built in 1819 by the United States Army, it attracted traders and merchants, spurring growth in the area. The United States government pressed the Mdewakanton band of the Dakota to sell their land, allowing people arriving from the East to settle there. Preoccupied with the Civil War, the United States government reneged on its promises of cash payments to the Dakota, resulting in hunger, the Dakota War of 1862, internment and hardship; the Minnesota Territorial Legislature authorized Minneapolis as a town in 1856, on the Mississippi's west bank. Minneapolis incorporated as a city in 1867, the year rail service began between Minneapolis and Chicago, it joined with the east-bank city of St. Anthony in 1872. Minneapolis developed around Saint Anthony Falls, the highest waterfall on the Mississippi River and a source of power for its early industry.
Forests in northern Minnesota were a valuable resource for the lumber industry, which operated seventeen sawmills on power from the waterfall. By 1871, the west river bank had twenty-three businesses, including flour mills, woolen mills, iron works, a railroad machine shop, mills for cotton, paper and planing wood. Due to the occupational hazards of milling, six local sources of artificial limbs were competing in the prosthetics business by the 1890s; the farmers of the Great Plains grew grain, shipped by rail to the city's 34 flour mills. Millers have used hydropower elsewhere since the 1st century B. C. but the results in Minneapolis between 1880 and 1930 were so remarkable the city has been described as "the greatest direct-drive waterpower center the world has seen." A father of modern milling in America and founder of what became General Mills, Cadwallader C. Washburn converted his business from gristmills to revolutionary technology, including "gradual reduction" processing by steel and porcelain roller mills capable of producing premium-quality pure white flour quickly.
Some ideas were developed by William Dixon Gray and some acquired through industrial espionage from Hungary by William de la Barre. Charles A. Pillsbury and the C. A. Pillsbury Company across the river were a step behind, hiring Washburn employees to use the new methods; the hard red spring wheat that grows in Minnesota became valuable, Minnesota "patent" flour was recognized at the time as the best in the world. Not until did consumers discover the value in the bran that "... Minneapolis flour millers dumped" into the Mississippi. After 1883, a Minneapolis miller started a new industry when he began to sell bran byproduct as animal feed. Millers cultivated relationships with academic scientists at the University of Minnesota; those scientists backed them politically on many issues, such as in the early 20th century when health advocates in the nascent field of nutrition criticized the flour "bleaching" process. At peak production, a single mill at Washburn-Crosby made enough flour for 12 million loaves of bread each day.
Further, by 1895, through the efforts of silent partner William Hood Dunwoody, Washburn-Crosby exported four