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  • Cash for Creativity | Time and Navigation
    the Exhibition Navigating at Sea Challenges of Sea Navigation Navigation Gone Wrong A British Fleet is Lost at Sea Navigate at Sea Activity Navigating Without a Clock Early Voyages Dead Reckoning Celestial Navigation The Longitude Problem Cash for Creativity Early Sea Clock Experiments Innovations in England Innovations in France The Chronometer Observing the Skies Navigation Gone Wrong Wreck of the Arniston The U S Goes to Sea Early Contributions Meet the Clockmaker William Cranch Bond Meet the Navigator Eleanor Creesy Wilkes Expedition Meet the Mapmaker Charles Wilkes Maps and Charts The Scientifics Navigate at Sea Activity Explore More World Map Heitiki Ornament Nocturnal and Sundial Galileo Galilei Latitude and Longitude Cash for Creativity European governments offered huge prizes to inspire a solution to the longitude problem Finding longitude at sea became urgent when European states competed for overseas empires and maritime trade Starting in the late 1500s Europe s major seafaring nations Spain the Netherlands Portugal the Venetian Republic England and France offered vast sums of money to anyone who could solve the longitude problem These prizes stimulated an inventive outpouring from both the greatest scientific minds and the humblest tinkerers Dutch vessels burning the English fleet Jan van Leyden Dutch vessels destroying the English fleet near Chatham England painted 1670 Credit By Permission of the Rijks Museum Amsterdam Longitude Act of 1714 This act authorized prizes up to 20 000 for solving the longitude problem Credit Library of Congress Ships in Distress off a Rocky Coast 1667 This painting by Ludolf Backhuysen depicts three Dutch cargo ships Credit Ludolf Backhuysen Ships in Distress off a Rocky Coast Ailsa Mellon Bruce Fund Image courtesy of the National Gallery of Art Washington previous pause resume next Navigating at Sea Challenges of Sea Navigation Navigating Without a Clock The Longitude Problem Cash

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/cash-for-creativity (2016-02-13)
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  • Early Sea Clock Experiments | Time and Navigation
    Sea Activity Explore More Titian Ramsay Peale Using a Mariner s Astrolabe Longitude Act of 1714 Dolphins Galileo s Giovilabio Replica Galileo Galilei Galileo Galilei Italian astronomer Galileo Galilei competed for two longitude prizes in the 17th century Credit Smithsonian Institution Libraries Early Sea Clock Experiments Prizes offered by Spain in 1598 and the Dutch Republic two years later stimulated the best scientific minds of the day to build better clocks for finding position at sea The challenge was enormous At that time no clock on land or sea could keep better time than within about 15 minutes a day But after nearly two centuries with the invention of the chronometer accuracy at sea improved to about 1 5th of a second a day One method of finding longitude is by a Watch to keep time exactly But by reason of the motion of the Ship the Variation of Heat and Cold Wet and Dry and the Difference of Gravity at different Latitudes such a watch hath not yet been made Sir Isaac Newton 1714 Galileo s Pendulum Clock Design Replica This is a replica of Galileo s design for a pendulum clock In 1642 for a Dutch longitude prize Galileo proposed both an astronomical solution and an accurate sea clock the first clock ever to have a pendulum Galileo died before making the clock but his son built a model in 1649 Learn more Christiaan Huygens In pursuit of a sea clock Christiaan Huygens a mathematician from the Netherlands changed timekeeping forever He patented the first working pendulum clock in 1656 and later devised a watch regulator called a balance spring These inventions became standard components for keeping good time Pendulum clocks immediately became the best timekeepers for use on land But several sea trials demonstrated to Huygens that

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/solving-longitude-problem/early-sea-clocks (2016-02-13)
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  • Innovations in England | Time and Navigation
    Cranch Bond Meet the Navigator Eleanor Creesy Wilkes Expedition Meet the Mapmaker Charles Wilkes Maps and Charts The Scientifics Navigate at Sea Activity Explore More Dolphins Marine Chronometer by Arnold Dent No 1131 Mariner s Astrolabe Map of the Coast of Antarctica Mice Innovations in England The loss of the British Fleet in 1707 near the Scilly Isles provoked demands for safer navigation Parliament passed the Longitude Act of 1714 which created a panel of experts to oversee rewards for solving the problem of finding longitude at sea The Longitude Act of 1714 specified levels of clock accuracy in terms of distance 1st prize 20 000 For accuracy of 1 2 degree of longitude or 30 nautical miles 2nd prize 15 000 For within 2 3 degree of longitude or 45 nautical miles 3rd prize 10 000 For within 1 degree of longitude or 60 nautical miles One degree of longitude at the equator equals 60 nautical miles 111 kilometers or 69 miles A Breakthrough John Harrison s Sea Clocks A stunning technical breakthrough came when English carpenter and clockmaker John Harrison built five prototype sea clocks between 1735 and 1772 This series of specialized timepieces convincingly demonstrated the feasibility of accurate timekeeping at sea Because of Harrison s improvements in technology his best clock tested at sea a large portable silver cased watch kept time with an accuracy of about 1 5th of a second per day Shortly before he died Harrison received nearly the full 20 000 that England had offered to anyone who could solve the longitude problem but not until King George III himself intervened Harrison sent his last sea clock to the king s private observatory in 1772 where George III witnessed its performance and deemed it prize worthy John Harrison Portrait of John Harrison

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/solving-longitude-problem/innovation-in-england (2016-02-13)
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  • Innovations in France | Time and Navigation
    Navigation Gone Wrong Wreck of the Arniston The U S Goes to Sea Early Contributions Meet the Clockmaker William Cranch Bond Meet the Navigator Eleanor Creesy Wilkes Expedition Meet the Mapmaker Charles Wilkes Maps and Charts The Scientifics Navigate at Sea Activity Explore More Mariner s Astrolabe Map of the Coast of Antarctica Line of Position Navigation Parrots Chronometer Movement John Roger Arnold Innovations in France Finding longitude at sea was a major preoccupation in France Thanks to a bequest from Rouillé de Meslay the French Academy of Sciences offered prizes for improving navigation and scientific voyaging beginning in 1714 just before the English Parliament s prize was authorized By the 1760s two competing clockmakers Pierre LeRoy and Ferdinand Berthoud devised marine timekeepers that underwent test voyages in 1769 and 1771 Pierre LeRoy After building three earlier marine timekeepers Pierre LeRoy completed a sea clock in 1766 that contained the elements of the modern chronometer a specialized escapement a specialized balance spring and a balance that compensated for temperature changes In 1769 the academy rewarded him with a Meslay prize for his work Like Harrison s timepieces LeRoy s were complex and his work was not copied directly by others Ferdinand Berthoud A Swiss expatriate working in Paris Ferdinand Berthoud saw John Harrison s earliest marine clocks in England and went on to produce his own His timekeepers never bested Pierre LeRoy s in sea trials but Berthoud made many more than his rival He claimed that over 50 of his timepieces went on 80 voyages One of Berthoud s sea clocks an uncommon weight driven design inspired Boston clockmaker William Bond to make a chronometer in the same style Escapement for Pierre LeRoy s marine clock 1766 This illustration from 1766 depicts the improved escapement in Le Roy s

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/solving-longitude-problem/innovation-in-france (2016-02-13)
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  • The Chronometer | Time and Navigation
    England Innovations in France The Chronometer Observing the Skies Navigation Gone Wrong Wreck of the Arniston The U S Goes to Sea Early Contributions Meet the Clockmaker William Cranch Bond Meet the Navigator Eleanor Creesy Wilkes Expedition Meet the Mapmaker Charles Wilkes Maps and Charts The Scientifics Navigate at Sea Activity Explore More Chart showing Nova Scotia to Cape Cod Wreck of the Association Dagger and Sheath The Clipper Ship Flying Cloud Using Lunar Distances to Find Longitude Chronometer 1802 Box chronometer after Thomas Mudge No 14 made by Howells Barraud and Jamison 1802 Credit National Museum of American History Smithsonian Institution The Chronometer Making the sea clock practical was critical to improving sea navigation To design and build a standardized seagoing timekeeper took decades John Harrison s timekeepers were ingenious but difficult to reproduce accurately and affordably Still they guided the work of later watchmakers whose modifications would standardize the portable timepieces that came to be known as marine chronometers Marine Chronometer Marine chronometers are precise specialized clocks for finding longitude at sea They serve as portable time standards Learn more Chronometer Movement John Roger Arnold Chronometer movement made by John Roger Arnold about 1825 Arnold received an award from the Board of Longitude on behalf of his deceased father John Arnold who had simplified parts of the chronometer Learn more Chronometer 1802 Thomas Mudge one of the watchmakers following Harrison designed this instrument Like Harrison s timepieces Mudge s were extremely inventive and complex And like Harrison he won funds from the Board of Longitude but had to struggle to receive them His son Thomas Mudge Jr engaged craftsmen to make 26 copies of his father s work for public sale This one is number 14 made by Howells Barraud and Jamison 1802 Learn more Wreck of the

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/solving-longitude-problem/chronometer (2016-02-13)
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  • Observing the Skies | Time and Navigation
    observations They convinced King Charles to establish an observatory at Greenwich in 1675 Two centuries later a line through his observatory would become Earth s Prime Meridian The octant and sextant were invented to make use of the observatory s new star catalogs published beginning in 1725 These portable angle measuring tools served two purposes improving latitude observations and finding longitude Celestial Navigation at Sea To locate themselves on the open ocean navigators can determine their position by observing the Sun Moon stars or planets Some of these techniques involved using the North Star the Lunar Distance Method and finding local noon with a sextant Learn more Using Lunar Distances to Find Longitude Using Lunar Distances to Find Longitude from Peter Apian Cosmographia Petri Apiani 1524 Astronomers had long known that the Moon changes its position against the background of the sky and stars fairly quickly It moves the distance of its own diameter in about hour a distance called a lunar This steady motion could be used to measure time To figure out longitude a navigator measured the separation between the Moon and a particular star Based on that separation he used a book of tables to look up the predicted time at a reference point such as Greenwich The difference between that reference time and the local time aboard ship was used to determine longitude Learn more Octant Octant marked Andrew Newell Maker Boston about 1800 Independently invented in England and the United States in 1730s the octant is a portable instrument for measuring the angle of the Sun the Moon or a star above the horizon The instrument s name comes from its scale which is 45 degrees or 1 8th of a circle Learn more Sextant Sextant made by Jesse Ramsden last quarter of 18th century

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/observing-the-skies (2016-02-13)
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  • Wreck of the Arniston | Time and Navigation
    Navigation Gone Wrong Wreck of the Arniston The U S Goes to Sea Early Contributions Meet the Clockmaker William Cranch Bond Meet the Navigator Eleanor Creesy Wilkes Expedition Meet the Mapmaker Charles Wilkes Maps and Charts The Scientifics Navigate at Sea Activity Explore More Parrots Using an Horary Quadrant World Map Dagger and Sheath Longitude Navigation Gone Wrong Wreck of the Arniston Sailing without a chronometer the Arniston crashed into reefs along the coast of South Africa and sank on May 30 1815 killing about 340 people The Problem The Arniston was a trading vessel contracted by the British Navy to bring wounded troops and civilians to England from Ceylon The ship lacked a chronometer because the captain could not afford one and the company that owned the ship considered them too expensive about 100 or less So the Arniston depended on daily signals from the other ships in its convoy to determine longitude The Consequences While sailing around the horn of Africa the Arniston became separated from the convoy during a period of strong winds and storms Unable to determine how far west the ship had sailed its captain headed north before he should have and slammed into the Lagullos Reef The crew tried to save the ship but it broke up in the sea killing all the passengers and all but six of the crew Lessons Learned The wreck of the Arniston proved the importance of having a maritime chronometer aboard every ship especially when sailing in dangerous waters By 1825 all ships in the Royal Navy were equipped with them Chronometers were supplied to American naval vessels by the early 1830s In this age of science it is indeed astonishing that any ship should ever be permitted to set out on any voyage without a chronometer Captain

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/longitude-problem/wreck-of-the-arniston (2016-02-13)
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  • Early Contributions | Time and Navigation
    Clock with Pendulum Early Contributions America s earliest contributions to navigation Intent upon contributing to the art and science of navigation civilian and naval innovators worked to lessen the dangers of seafaring by seeking better ways to find time and place Major contributions included A Navigation Encyclopedia The New American Practical Navigator has served American sailors since 1802 Popularly known as Bowditch s for its first compiler Nathaniel Bowditch it remains a useful handbook of astronomical tables meteorological information and navigational instructions America s First Sea Going Chronomenter This timekeeper was the first American made marine timekeeper taken to sea William Cranch Bond a 23 year old Boston clockmaker crafted it during the War of 1812 It went to sea only once on a voyage to Sumatra now in Indonesia aboard the U S Navy vessel Cyrus in 1818 Chronometers would not be common aboard American ships until about 1830 Bond s chronometer differed from spring powered English models Unable to buy British spring steel in wartime Bond used a French design powered by a falling weight Navigation By Line of Position While nearing land on his way to Scotland in 1837 Captain Thomas Sumner of Boston had an insight that made an enduring contribution to navigation Cloudy weather permitted only one sighting on the Sun With that limited information Sumner made three different calculations based on estimates of his latitude Plotted on a chart the results lay along a straight line He realized that any ship seeing the Sun at the same altitude in the sky must be located somewhere on that line This was confirmed by sailing along that course until a lighthouse was sighted on the coast Sumner published his method for determining what was later called a line of position in 1843 and it became standard

    Original URL path: http://timeandnavigation.si.edu/navigating-at-sea/us-goes-to-sea/early-contributions (2016-02-13)
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