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Bangui magnetic anomaly

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The Bangui magnetic anomaly is a local variation in the Earth's magnetic field centered at Bangui , the capital of the Central African Republic . The magnetic anomaly is roughly elliptical , about 700 km × 1,000 km (430 mi × 620 mi), and covers most of the country, making it one of the "largest and most intense crustal magnetic anomalies on the African continent". The anomaly was discovered in the late 1950s, explored in the 1970s, and named in 1982. Its origin remains unclear.

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63-570: In 1962, Raymond Godivier and Lucien Le Donche reported on a magnetic anomaly in the Central African Republic, which they identified by analyzing their surface magnetic activity data of 1956. These results were confirmed and built upon by the high-altitude aeromagnetic surveys carried out by the US Naval Oceanographic Office , as well as by the satellite measurements conducted in 1964 with Cosmos 49 and in

126-432: A Bouguer gravity anomaly of −120 mGal , a topographical surface feature shaped as a ring of 810 km (500 mi) diameter, rock features of Late Archean and Proterozoic periods in the central part of the anomaly, granulites , and charnockites rock formations supplemented by granites at the lower crust level, and greenstone belts, and metamorphosed basalts seen as rock exposures. A zone of thinner crust bounds

189-488: A captain's uniform while being commissioned only as a Lieutenant, rankled heavily with other members of the expedition of similar real rank. His apparent mistreatment of many of his subordinates, and indulgence in punishments such as " flogging round the fleet " resulted in a major controversy on his return to America. Wilkes was court-martialled on his return, but was acquitted on all charges except that of illegally punishing men in his squadron. The Wilkes Expedition played

252-654: A force of around 700 Gilbertese warriors opposed the American assault, but were defeated after a long battle. No Americans were hurt, but twelve natives were killed and others were wounded, and two villages were also destroyed. A similar episode occurred two months before in February when the Peacock and the Flying Fish briefly bombarded the island of Upolu , Samoa following the death of an American merchant sailor on

315-561: A length of 208 feet, both ships were slightly smaller than the T-AGS 60 class ships. Both were capable of collecting hydrographic data on all headings in seas with wave heights up to 9 feet and could launch and recover two HSLs and other survey equipment in seas up to 4 feet. McDonnell was decommissioned on 25 August 2010. Littlehales was transferred to the National Oceanic and Atmospheric Administration (NOAA) on 3 March 2003. She

378-411: A major role in the development of 19th-century science, particularly in the growth of the American scientific establishment. Many of the species and other items found by the expedition helped form the basis of collections at the new Smithsonian Institution . With the help of the expedition's scientists, derisively called " clam digger s" and " bug catchers " by navy crew members, 280 islands, mostly in

441-691: A minimum of time to keep up with fleet advances across the Pacific. At the peak of World War II, 43 million charts were printed and issued in one year. The Hydrographic Office was redesignated U.S. Naval Oceanographic Office (NAVOCEANO) in 1962, and in 1976 the Office was relocated to the National Space Technology Laboratory (NSTL), which is now known as the John C. Stennis Space Center, in south Mississippi. NAVOCEANO oversees

504-746: A misunderstanding of each other's intentions, the Porpoise and Astrolabe were unable to communicate. In February 1840, some of the expedition were present at the initial signing of the Treaty of Waitangi in New Zealand. Some of the squadron then proceeded back to Sydney for repairs, while the rest visited the Bay of Islands , before arriving in Tonga in April. At Nuku'alofa they met King Josiah (Aleamotu'a), and

567-583: A part of the Smithsonian Institution. There were also 254 live plants, which mostly came from the home stretch of the journey, that were placed in a newly constructed greenhouse in 1850, which later became the United States Botanic Garden . Alfred Thomas Agate , an engraver and illustrator, created an enduring record of traditional cultures such as the illustrations made of the dress and tattoo patterns of natives in

630-623: A resolution on May 21, 1828, requesting President John Quincy Adams to send a ship to explore the Pacific. Adams was keen on the resolution and ordered his Secretary of the Navy to ready a ship, the Peacock . The House voted an appropriation in December but the bill stalled in the US Senate in February 1829. Then, under President Andrew Jackson , Congress passed legislation in 1836 approving

693-510: A seventh (T-AGS-67) currently under construction. The T-AGS 60 class ships were designed and constructed to provide multipurpose oceanographic capabilities in coastal and deep-ocean areas for NAVOCEANO. On board, surveyors are equipped to conduct physical, chemical and biological oceanographic operations; multidisciplinary environmental investigations; ocean engineering and marine acoustics; marine geology and geophysics; and bathymetric, gravimetric and magnetometric surveying. Typical missions of

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756-486: A small force of marines and sailors, under William M. Walker , to search the island. Initially, the natives were peaceful and the Americans were able to explore the island, without results. It was when the party was returning to their ship that Hudson noticed a member of his crew was missing. After making another search, the man was not found and the natives began arming themselves. Lieutenant Walker returned his force to

819-511: A visit to Wake Island , and returned by way of the Philippines , Borneo , Singapore , Polynesia , and the Cape of Good Hope , reaching New York on June 10, 1842. The expedition was plagued by poor relationships between Wilkes and his subordinate officers throughout. Wilkes' self-proclaimed status as captain and commodore, accompanied by the flying of the requisite pennant and the wearing of

882-545: The Columbia River on June 21. In April 1841, USS Peacock , under Lieutenant William L. Hudson , and USS Flying Fish , surveyed Drummond's Island , which was named for an American of the expedition. Lieutenant Hudson heard from a member of his crew that a ship had wrecked off the island and her crew massacred by the Gilbertese . A woman and her child were said to be the only survivors, so Hudson decided to land

945-608: The Department of Defense . The Royal Navy created the post of Hydrographer of the Navy in 1795, which within five years was producing naval charts for naval and merchant use. In 1830, the U.S. Navy established the Depot of Charts and Instruments maintain a supply of navigational instruments and nautical charts for issue to naval vessels. It soon became apparent that the Depot would be unable to obtain and maintain an adequate supply of

1008-780: The Ellice Islands in present-day Tuvalu . A collection of artifacts from the expedition also went to the National Institute for the Promotion of Science , a precursor of the Smithsonian Institution . These joined artifacts from American history as the first artifacts in the Smithsonian collection. For a short time Wilkes was attached to the Office of Coast Survey , but from 1844 to 1861 he

1071-527: The Fraser River . Wilkes visited Fort Clatsop , John McLoughlin at Fort Vancouver , and William Cannon on the Willamette River , while he sent Lt. Johnson on an expedition to Fort Okanogan , Fort Colvile and Fort Nez Perces , where they met Marcus Whitman . Like his predecessor, British explorer George Vancouver , Wilkes spent a good deal of time near Bainbridge Island . He noted

1134-588: The Hudson's Bay Company , and the American Methodist Mission at Point Adams. They also traded with the local Clatsop and Chinookan Indians over the next three weeks, while surveying the channel, before journeying to Fort George and a reunion with the rest of the squadron. This prompted Wilkes to send the Vincennes to San Francisco Bay, while he continued to survey Grays Harbor . From

1197-764: The Naval Ice Center in Suitland, Maryland, and the Fleet Survey Team at Stennis Space Center, Mississippi. NAVOCEANO is the largest subordinate command under the Commander, Naval Meteorology and Oceanography Command, which is also located at Stennis Space Center. NAVOCEANO's seven oceanographic ships are operated by the Military Sealift Command . The oceanographic survey ships have no homeport and are forward-deployed, surveying

1260-430: The Peacock went aground while attempting to enter the Columbia River and was soon lost, though with no loss of life. The crew was able to lower six boats and get everyone into Baker's Bay, along with their journals, surveys, the chronometers, and some of Agate's sketches. A one-eyed Indian named George then guided the Flying Fish into the same bay. There, the crew set up "Peacockville", assisted by James Birnie of

1323-615: The Sea Gull was reported missing. On June 6, the squadron arrived at San Lorenzo , off Callao for repair and provisioning, while Wilkes dispatched the Relief homewards on June 21. Leaving South America on July 12, the expedition reached Reao of the Tuamotu Group on August 13, and Tahiti on September 11. They departed Tahiti on October 10. The expedition then visited Samoa and New South Wales , Australia. In December 1839,

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1386-641: The Tokelau Islands, and Fakaofo . The Peacock followed this with surveys of the Tuvalu islands of Nukufetau , Vaitupu , and Nanumanga in March. In April, the Peacock surveyed the Gilbert Islands of Tabiteuea , Nonouti , Aranuka , Maiana , Abemama , Kuria , Tarawa , Marakei , Butaritari , and Makin , before returning to Oahu on June 13. The Peacock and Flying Fish then left for

1449-681: The Vincennes in Sausalito on October 23, having traveled along the Siskiyou Trail . Wilkes arrived with the Porpoise and Oregon , while the Flying Fish was to rendezvous with the squadron in Honolulu. The squadron surveyed San Francisco and its tributaries, and later produced a map of "Upper California". The expedition then headed back out on October 31, arriving Honolulu on November 17, and departing on November 28. They included

1512-557: The brig USS  Porpoise (230 tons), the full-rigged ship Relief , which served as a store-ship , and two schooners , Sea Gull (110 tons) and USS  Flying Fish (96 tons), which served as tenders . On August 18, 1838, the vessels left the naval port of Hampton Roads , Virginia. The fleet then headed to Madeira , taking advantage of the prevailing winds. The expedition consisted of nearly 350 men, many of whom were not assigned to any specific vessel. Others served on more than one vessel. Wilkes

1575-545: The 1970s with the Orbiting Geophysical Observatory at 350–500 kilometres (220–310 mi) altitudes. This data was combined in 1973 and yielded a spatial map of Earth's magnetic field, which was then updated after the launch of the Magsat satellite with an accuracy of 15  nT at an altitude of 400 kilometres (250 mi). In 1982, Robert D. Regan and Bruce D. Marsh named the anomaly after

1638-745: The 329-foot-long (100 m) T-AGS 60 vessels may include oceanographic sampling and data collection of surface water, mid-water and ocean floor parameters; the launch and recovery of small boats known as hydrographic survey launches (HSLs); the launching, recovering and towing of scientific packages (both tethered and autonomous) including the handling, monitoring and servicing of remotely operated vehicles (ROVs); shipboard oceanographic data processing and sample analysis; and precise navigation, trackline maneuvering and station-keeping to support deep-ocean and coastal surveys. NAVOCEANO formerly operated two coastal hydrographic T-AGS 50 class ship, John McDonnell  (T-AGS-51) , and Littlehales  (T-AGS-52) . At

1701-552: The Antarctic Continent." Named Wilkes Land , it includes Claire Land , Banzare Land , Sabrina Land , Budd Land , and Knox Land . They charted 1,500 miles (2,400 kilometers) of Antarctic coastline to a westward goal of 105° E., the edge of Queen Mary Land , before departing to the north again on February 21. The Porpoise came across the French expedition of Jules Dumont d'Urville on January 30. However, due to

1764-504: The Central African Republic and Brazil. Naval Oceanographic Office The Naval Oceanographic Office (NAVOCEANO), located at John C. Stennis Space Center in south Mississippi , is an echelon IV component of the Naval Meteorology and Oceanography Command (NMOC) and comprises approximately 1,000 civilian, military and contract personnel responsible for providing oceanographic products and services to all elements within

1827-480: The Depot needed a way to gather information quickly on a worldwide basis. Naval officer Matthew Fontaine Maury , who became known as "The Pathfinder of the Seas", supplied the answer to this dilemma. Commander Maury, who held the position of Hydrographer of the Navy from 1842 to 1861, is credited with founding the science of oceanography. His system for collecting and using oceanographic data revolutionized navigation of

1890-686: The George (Taufa'ahau), chief of Ha'apai , before proceeding onwards to Fiji on May 4. The Porpoise surveyed the Low Archipelago, while the Vincennes and Peacock proceeded onwards to Ovalau , where they signed a commercial treaty with Tanoa Visawaqa in Levuka . Edward Belcher 's HMS  Starling visited Ovalau at the same time. Hudson was able to capture Vendovi, after holding his brothers Cocanauto, Qaraniqio, and Tui Dreketi ( Roko Tui Dreketi or King of Rewa Province ) hostage. Vendovi

1953-703: The November 27, setting a record for slowness, 100 days. While there, they used Enxados Island in Guanabara Bay for an observatory and naval yard for repair and refitting. The Squadron did not leave Rio de Janeiro until January 6, 1839, arriving at the mouth of the Río Negro on January 25. On February 19, the squadron joined the Relief , Flying Fish , and Sea Gull in Orange Harbor, Hoste Island , after passing through Le Maire Strait . While there,

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2016-427: The Office's mission had expanded to include "the carrying out of surveys, the collection of information and the printing of every kind of nautical chart or publication." The Office continued to grow throughout the nineteenth century. By the turn of the century, pleasure cruises had become a popular form of vacationing, and suddenly the attention of the world was drawn to a new danger to navigation – ice. The collision of

2079-476: The Pacific, were explored, and over 800 miles (1,300 kilometers) of Oregon were mapped. Of no less importance, over 60,000 plant and bird specimens were collected. A staggering amount of data and specimens were collected during the expedition, including the seeds of 648 species, which were later traded, planted, and sent throughout the country. Dried specimens were sent to the National Herbarium , now

2142-556: The Titanic with an iceberg in 1912 prompted the Hydrographic Office to urge that an ice patrol be established to document sea-ice hazards to prevent such disasters. This was the beginning of today's sophisticated, high-tech methods of surveying, measuring and recording ice thickness, ice-ridge profiles and other characteristics to monitor ocean-ice conditions above and below the surface. Because features and conditions of

2205-463: The Winds . The Smithsonian Institution digitized the five volume narrative and the accompanying scientific volumes. The mismanagement that plagued the expedition prior to its departure continued after its completion. By June 1848, many of the specimens had been lost or damaged and many remained unidentified. In 1848 Asa Gray was hired to work on the botanical specimens, and published the first volume of

2268-743: The anomaly to the north and a zone of relatively thicker crust is on the southern edge. Two theories have been suggested for the origin of the Bangui anomaly, neither being conclusive. One theory points to a large igneous intrusion and the other to a meteorite impact in the Precambrian (before 540 Ma ). To support the latter theory, a connection was drawn with a meteorite impact that may have occurred in Brazil in Bahia state causing formation of carbonados (black diamond aggregates) which are found only in

2331-497: The area of modern-day Portland , Wilkes sent an overland party of 39 southwards, led by Emmons, but guided by Joseph Meek . The group included Agate, Eld, Colvocoresses, Brackenridge, Rich, Peale, Stearns, and Dana, and proceeded along an inland route to Fort Umpqua , Mount Shasta , the Sacramento River , John Sutter 's New Helvetia , and then onwards to San Francisco Bay . They departed September 7, and arrived aboard

2394-403: The benefit of all. Within five years, 26 million reports poured into the Depot, which originally had been intended only as a storehouse of charts and instruments. In 1854, the agency was given the official name of The U.S. Naval Observatory and Hydrographical Office . In 1866, an Act of Congress separated the two functions, establishing the Hydrographic Office as a distinct activity. By this time

2457-515: The bird-like shape of the harbor at Winslow and named it Eagle Harbor . Continuing his fascination with bird names, he named Bill Point and Wing Point. Port Madison, Washington and Points Monroe and Jefferson were named in honor of former United States presidents. Port Ludlow was assigned to honor Lieutenant Augustus Ludlow , who lost his life during the War of 1812 . The Peacock and Flying Fish arrived off Cape Disappointment on July 17. However,

2520-596: The city located at its center. The anomaly is sometimes called the Bangui negative anomaly, owing to its negative peak-to-trough difference, and is compared with the positive anomalies observed at the Benue Trough and Congo Basin where Lower Cambrian geological formations are exposed. The Bangui anomaly is bounded to the south by the Walvis Ridge , the north by the Cameroon–St. Helena volcanic line , and to

2583-442: The coasts of both Americas, and far into the west and southwest Pacific. It began the U.S. collection of world magnetic data and contributed substantially to hydrographic, meteorological, botanical and geological knowledge of the explored regions. During the succeeding five years, 87 similar charts were published and issued from the results of surveys by Wilkes and his officers. These individual surveys, however, were limited in scope;

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2646-489: The command. Wilkes had a reputation for hydrography , geodesy , and magnetism . Additionally, Wilkes had received mathematics training from Nathaniel Bowditch , triangulation methods from Ferdinand Hassler , and geomagnetism from James Renwick . Personnel included naturalists , botanists , a mineralogist , a taxidermist , and a philologist . They were carried aboard the sloops-of-war USS  Vincennes (780 tons), and USS  Peacock (650 tons),

2709-638: The expedition came in contact with the Fuegians . Wilkes sent an expedition south in an attempt to exceed Captain Cook 's farthest point south, 71°10'. The Flying Fish reached 70° on March 22, in the area about 100 miles (160 kilometers) north of Thurston Island , and what is now called Cape Flying Fish , and the Walker Mountains . The squadron joined the Peacock in Valparaiso on May 10, but

2772-888: The expedition sailed from Sydney into the Antarctic Ocean and reported the discovery of the Antarctic continent on January 16, 1840, when Henry Eld and William Reynolds aboard the Peacock sighted Eld Peak and Reynolds Peak along the George V Coast . On the January 19, Reynolds spotted Cape Hudson . On January 25, the Vincennes sighted the mountains behind the Cook Ice Shelf , similar peaks at Piner Bay on January 30, and had covered 800 miles (1,300 kilometers) of coastline by February 12, from 140° 30' E. to 112° 16' 12"E., when Wilkes acknowledged they had "discovered

2835-585: The exploration mission. Again, the effort stalled under Secretary of the Navy Mahlon Dickerson until President Martin Van Buren assumed office and pushed the effort forward. Originally, the expedition was under the command Commodore Jones , but he resigned in November 1837, frustrated with all of the procrastination. Secretary of War Joel Roberts Poinsett , in April 1838, then assigned command to Wilkes, after more senior officers refused

2898-542: The ground. The Americans landed sixty sailors to attack the hostile natives. Close to eighty Fijians were killed in the resulting American reprisal and two villages were burned to the ground. On August 9, after three months of surveying, the squadron met off Macuata . The Vincennes and Peacock proceeded onwards to the Sandwich Islands, with the Flying Fish and Porpoise to meet them in Oahu by October. Along

2961-524: The island. The Vincennes and Porpoise reached Cape Disappointment on April 28, 1841, but then headed north to the Strait of Juan de Fuca , Port Discovery , and Fort Nisqually , where they were welcomed by William Henry McNeill and Alexander Caulfield Anderson . The Porpoise surveyed the Admiralty Inlet , while boats from the Vincennes surveyed Hood Canal , and the coast northwards to

3024-404: The latest data unless it undertook production of charts from its own surveys. In 1837, the first survey sponsored by the Depot and led by Lieutenant Charles Wilkes resulted in four engraved charts published for use by the U.S. Navy. Lieutenant Wilkes continued his surveying and gained fame as leader of the U.S. Exploring Expedition . The expedition ranged over the eastern Atlantic to Antarctica,

3087-485: The ocean 365 days every year. To avoid interrupting continuous operations, oceanographers from NAVOCEANO relieve their fellow surveyors by flying to locations around the world to meet the ship. NAVOCEANO has operational control of six T-AGS 60 class ships: Pathfinder  (T-AGS-60) , Bowditch  (T-AGS-62) , Henson  (T-AGS-63) , Bruce C. Heezen  (T-AGS-64) , Marie Tharp  (T-AGS-66) (formerly USNS Maury ), and Mary Sears  (T-AGS-65) , with

3150-489: The original expedition was requested by President John Quincy Adams in 1828; however, Congress would not implement funding until eight years later. In May 1836, the oceanic exploration voyage was finally authorized by Congress and created by President Andrew Jackson . The expedition is sometimes called the U.S. Ex. Ex. for short, or the Wilkes Expedition in honor of its next appointed commanding officer, United States Navy Lieutenant Charles Wilkes . The expedition

3213-439: The seas. Maury assumed command of the Navy's Depot of Charts and Instruments in 1842. Possessing an active, scientific mind, he immediately recognized possibilities for expanding the services of the Depot. Following the example of the Royal Navy 's Hydrographer of the Navy , he suggested that, if all U.S. shipmasters would submit reports of their experiences to a central agency, the data could be digested, compiled and published for

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3276-402: The ship, to converse with Hudson, who ordered Walker to return to shore and demand the return of the sailor. Walker then reboarded his boats with his landing party and headed to shore. Walker shouted his demand and the natives charged for him, forcing the boats to turn back to the ships. It was decided on the next day that the Americans would bombard the hostiles and land again. While doing this,

3339-406: The son of the local chief, who was being held as a hostage by the Americans, escaped by jumping out of the boat and running through the shallow water for shore. The Americans fired over his head. According to members of the expedition party on the boat, his escape was intended as a prearranged signal by the Fijians to attack. According to those on shore, the shooting actually precipitated the attack on

3402-421: The way, Wilkes named the Phoenix Group and made a stop at the Palmyra Atoll , making their group the first scientific expedition in history to visit Palmyra. While in Hawaii, the officers were welcomed by Governor Kekūanaōʻa , King Kamehameha III , his aide William Richards , and the journalist James Jackson Jarves . The expedition surveyed Kauai , Oahu , Hawaii , and the peak of Mauna Loa . The Porpoise

3465-447: The west by the Mid-Atlantic Ridge . It is shaped approximately as an ellipse 700 km × 1,000 km (430 mi × 620 mi) in size. It has three sections, and the magnetic equator runs through its center. It has a short axis diameter of about 550 kilometres (340 mi), and its amplitude varies between –1000 nT at ground level and –20 nT at satellite altitude, about 400 kilometres (250 mi). Its features include

3528-419: The world's oceans are constantly changing, surveying, charting and mapping must be continuous processes. Experiences during World War I showed the need for greater accuracy for oceanographic data. By 1922, responding to these needs, the Navy had developed the first practical sonic sounding machine, making it possible to surpass all previous efforts in deep-sea sounding and bathymetric charting . Aerial photography

3591-418: Was commissioned into the NOAA Atlantic Fleet as NOAAS Thomas Jefferson (S 222) on 8 July 2003. United States Exploring Expedition The United States Exploring Expedition of 1838–1842 was an exploring and surveying expedition of the Pacific Ocean and surrounding lands conducted by the United States. The original appointed commanding officer was Commodore Thomas ap Catesby Jones . Funding for

3654-635: Was chiefly engaged in preparing the expedition report. Twenty-eight volumes were planned, but only nineteen were published. Of these, Wilkes wrote the multi-volume Narrative of the United States exploring expedition, during 1838, 1839, 1840, 1841, 1842 , Hydrography , and Meteorology . The Narrative concerns the customs, political and economic conditions of many places then little-known. Other contributions were three reports by James Dwight Dana on Zoophytes , Geology , and Crustacea . In addition to shorter articles and reports, Wilkes published Western America, including California and Oregon , and Theory of

3717-552: Was deemed responsible for the attack against US sailors on Ono Island in 1836. Vendovi was taken back to the US, but died shortly after his arrival in New York. His skull was then added to the expedition collections and put on display in the Patent Office building in Washington, D.C. In July 1840, two members of the party, Lieutenant Underwood and Wilkes' nephew, Midshipman Wilkes Henry, were killed while bartering for food in western Fiji 's Malolo Island. The cause of this event remains equivocal. Immediately prior to their deaths,

3780-474: Was dispatched in November to survey several of the Tuamotus , including Aratika , Kauehi , Raraka , and Katiu , and then proceeded to Penrhyn before returning to Oahu on 24 March. On April 5, 1841, the squadron departed Honolulu , the Porpoise and Vincennes for the Pacific Northwest, the Peacock and Flying Fish to resurvey Samoa, before rejoining the squadron. Along the way, the Peacock and Flying Fish surveyed Jarvis Island , Enderbury Island ,

3843-399: Was of major importance to the growth of science in the United States, in particular the then-young field of oceanography . During the event, armed conflict between Pacific islanders and the expedition was common and dozens of natives were killed in action, as well as a few Americans. Through the lobbying efforts of Jeremiah N. Reynolds , the United States House of Representatives passed

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3906-428: Was to search in the Atlantic for various vigias or shoals, such as those reported by John Purdy , but failed to corroborate those claims for the locations given. The squadron arrived in the Madeira Islands on September 16, 1838, and Porto Praya on October 6. The Peacock arrived at Rio de Janeiro on November 21, and the Vincennes with brigs and schooners on November 24. However, the Relief did not arrive until

3969-559: Was used for the first time that year. Following the attack on Pearl Harbor , the demands for charts increased to about 40 times the normal pre-war rate. The Hydrographic Office was moved to more adequate facilities at Suitland, Maryland , about 6 miles (10 km) from the nation's Capitol building, and was placed under the cognizance of the Chief of Naval Operations to focus activities directly to programs of national security. Additional survey vessels were obtained, each equipped to conduct surveys and to produce printed charts aboard ship in

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