You can see that in what we are doing with our new Master Chronometers.
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Today the valley is lined with nearly a dozen high-end makers of mechanical watches and chronometers, each with its own renaissance story.
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That version of the story ignores the contributions of other clockmakers in the UK and in France who also were making progress toward developing reliable chronometers.
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Eagleman even attached chronometers with varying speeds to the participants to see if their brains sped up as they flew, which would allow them to read rapidly-rotating numbers.
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Harrison's 18th-century marine chronometers, for example, were essential navigation tools and played a significant role in the successes of the Royal Navy and the growth of the British Empire.
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Placed into service in 1845, it dropped the ball from a mast every day except Sunday at precisely mean solar noon in Washington, which enabled the navigators of ships anchored in the Potomac River to recalibrate their chronometers.
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Then located on a hill north of where the Lincoln Memorial now stands, the observatory, one of the oldest scientific agencies in the United States, expanded the mission assigned to the Navy's depot of charts and instruments, formed in 1830 to care for its chronometers, charts and other navigational equipment.
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Thomas Mercer Chronometers is a British company specialising in the design and production of bespoke chronometers.
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Spring-driven chronometers must be wound at about the same time each day. Quartz crystal marine chronometers have replaced spring-driven chronometers aboard many ships because of their greater accuracy. They are maintained on GMT directly from radio time signals. This eliminates chronometer error and watch error corrections.
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Since the 1870s, over 50 navies and international shipping companies had been equipped with Ulysse Nardin marine chronometers. In 1975, the Neuchâtel Observatory published the last official edition on the performance of chronometers from 1846 to 1975. According to this report, Ulysse Nardin was awarded 4,324 performance certificates for mechanical marine chronometers out of 4,504 submitted (95%).
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Edward John Dent (1790-1853) discovered his passion for horology from his cousin, Richard Rippon, himself a master watchmaker. Dent established his own company in 1814, and developed a reputation as a builder of accurate chronometers. One of his chronometers won the First Premium Award in the 1829 Greenwich Trials. The Royal Navy equipped themselves with Dent's chronometers.
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Bellingshausen noted that after the death of astronomer Nevil Maskelyne, the maritime almanac lost its preciseness. He found no less than 108 errors in the 1819 volume. The chronometers recommended by Joseph Banks, who promoted the interests of Arnold's family, were unsuitable. The same firm set up for James Cook "very bad chronometers" that were ahead by 101 seconds per day. Bulkeley called the quality of chronometers on ‘Vostok’ "horrifying". By May 1820 the chronometers on ‘Mirny’ were ahead by 5–6 minutes per day.
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54 and 55, for trial at Greenwich. This must indicate that he had made at least 55 chronometers by 1826. His submitting chronometers for trial brought him to the notice of the authorities at Royal Observatory, Greenwich.
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21 (1878-79), 58-59; 75 Charles Frodsham, marine chronometer no. 1842 The firm continued to supply marine chronometers to the Greenwich trials, achieving significant success. Between 1831 and 1920, the Admiralty purchased sixty Charles Frodsham marine chronometers, and a number of pocket chronometers and deck watches, most notably a watch used by Ruth Belville, the Greenwich Time Lady, now in the Lord Harris collection at Belmont.
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By 1840, this number had reduced to only 200. Even though the navy only officially equipped their vessels with chronometers after 1825, this shows that the number of chronometers required by the navy was shrinking in the early 19th century. Mörzer Bruyns identifies a recession starting around 1857 that depressed shipping and the need for chronometers. Also, many merchant mariners would make do with a deck chronometer at half the price.
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The advantage of using chronometers was that though astronomical observations were still needed to establish local time, the observations were simpler and less demanding of accuracy. Once local time had been established, and any necessary corrections made to the chronometer time, the calculation to obtain longitude was straightforward. The disadvantage of cost gradually became less as chronometers began to be made in quantity. The chronometers used were not those of Harrison.
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Used in chronometers and other fine time pieces where the spring is an overcoil.
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In 1819, William Parry spent five weeks reconciling his chronometers in the Greenwich Royal Observatory, while Simonov dedicated no less than 40% of his observation time on the calibration of chronometers and establishing correct time. The deep-sea thermometer broke during its second use.
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Despite Ulysse Nardin growing up in the Jura mountains, he was fascinated by the sea and produced nautical timekeeping instruments. His company became one of the first to manufacture marine chronometers and high-precision seafaring instruments for commercial ships and navies throughout the world. His pocket and marine chronometers became reference products in civil, military and scientific realms. Ulysse Nardin acquired a high-precision astronomical regulator, built by Jacques-Frederic Houriet in 1768, to rate his pocket chronometers.
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Two provided dual modular redundancy, allowing a backup if one should cease to work, but not allowing any error correction if the two displayed a different time, since in case of contradiction between the two chronometers, it would be impossible to know which one was wrong (the error detection obtained would be the same of having only one chronometer and checking it periodically: every day at noon against dead reckoning). Three chronometers provided triple modular redundancy, allowing error correction if one of the three was wrong, so the pilot would take the average of the two with closer readings (average precision vote). There is an old adage to this effect, stating: "Never go to sea with two chronometers; take one or three." Some vessels carried more than three chronometers - for example, HMS Beagle carried 22 chronometers.
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It is now in a museum in Le Locle. Minute repeaters, complicated watches and pocket chronometers carried the reputation of the company. Rolf Schnyder and Ludwig Oechslin At that time, famous horologists were French and English. Ulysse Nardin went to London to challenge the best pocket chronometers makers.
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Private Publication. See pages 161-182. The facts prove that authors such as Gould and Sobel are quite incorrect in their assertion that there was commercial rivalry between Arnold Sr. and Earnshaw.Antiquarian Horology Volume 17 No.4 Pages 368 - 371 This is demonstrated by the fact that between 1783 and 1796, even excluding marine chronometers, Arnold is known to have produced at least 500 pocket chronometers, whilst Earnshaw made only a few chronometers, perhaps less than fifty, during this period.
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Many historians point to relatively low production volumes over time as evidence that the chronometers were not widely used. However, Landes points out that the chronometers lasted for decades and did not need to be replaced frequently – indeed the number of makers of marine chronometers reduced over time due to the ease in supplying the demand even as the merchant marine expanded.This book has a table showing that at the peak just prior to the War of 1812, Britain's Royal Navy had almost 1000 ships.
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Arnold and Dent have just completed another of those beautiful > specimens of art, in the shape of a pocket chronometer, showing at once both > mean and sidereal time. This is the fourth of these machines that has been > made. In an article entitled Hints on Chronometers appearing in Nautical Magazine and dated February 1833, Dent reveals that chronometer No. 633 was sent with 21 other chronometers to Captain FitzRoy on board in 1831. In fact, several of these chronometers were by Arnold and Dent.
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These 40 movements were tested for another 45 days, it was these 40 that became the Girard Perregaux Observatory Chronometers. Similarly in 1968, 1969 and 1970 Seiko had 226 wristwatches with its 4520 and 4580 Calibres certified as observatory chronometers. In both cases these observatory chronometers were then sold to the public for normal usage as wristwatches, and some examples may still be found today, although they are very rare. The Girard-Perregaux Calibre 32A movement that went into its Observatory Chronometers heralded a shift in watchmaking technology to higher frequency movements, and thus greater accuracy, that is followed today by watch manufacturers such as Seiko, Patek Philippe, Zenith, Audemars Piguet, Jaeger-LeCoultre, Chopard, Vacheron Constantin, Mathey-Tissot and such.
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Indeed, in 1828 Dent was employed by Royal Observatory, Greenwich to examine and repair chronometers. His charges for repairing chronometers were as high as 25 guineas – an apparently exorbitant cost, but one that was nevertheless accepted.Mercer, Vaudrey (1977). The Life and Letters of Edward John Dent, Chronometer Maker and some account of his Successors, p.
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Moreover, most of the time that was spent on scientific observations, Simonov dedicated to the time-consuming process of reconciling ship chronometers. 70 out of 155 pages of Simonov's scientific report were dedicated to these calculations, which constituted 40% out of the total volume. Chronometers reconciliation took place in Rio, during stays in Sydney and the Cook Strait.
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In late 1837 he married Rebecca Roberts of Alexandria, D.C. (now Va.). The Depot of Charts and Instruments was headed by Charles Wilkes. The depot was responsible for the navy's chronometers, charts, and other navigational instruments and provided Gilliss with an opportunity to practice astronomy. Astronomical observations were necessary to determine the accuracy of the Navy's chronometers.
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Today only a handful of Earnshaw chronometers are known that date from before 1796 and, significantly, all have (or originally had) flat springs.
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An Admiralty memorandum set out the detailed instructions. The first requirement was to resolve disagreements in the earlier surveys about the longitude of Rio de Janeiro, which was essential as the base point for meridian distances. The accurate marine chronometers needed to determine longitude had only become affordable since 1800; Beagle carried 22 chronometers to allow corrections. The ship was to stop at specified points for four-day rating of the chronometers and to check them by astronomical observations: it was essential to take observations at Porto Praya and Fernando de Noronha to calibrate against the previous surveys of Owen and Foster.
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Through its manufacture, Ditisheim was instrumental in developing the new generation of chronometers, improving them grandly through his studies on the impact of atmospheric pressure and magnetic fields. He invented the affix balance. Thanks to his inventions, he was able to make the most precise chronometers ever made. By 1903, his watches were awarded by the Kew and Neuchâtel Observatories contests.
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Edward John Dent (1790–1853) was a famous English watchmaker noted for his highly accurate clocks and marine chronometers. He founded the Dent company.
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Around 1726 John Harrison added the maintaining power spring to the fusee to keep marine chronometers running during winding, and this was generally adopted.
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There exist other naturally occurred radioactive isotopes of lanthanides with long half-lives (144Nd, 150Nd, 148Sm, 151Eu, 152Gd) but they are not used as chronometers.
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Frodsham was educated at the Bluecoat School, Newgate,Mercer, Frodshams, p. 76 London and then apprenticed to his father William James Frodsham FRS, a respected chronometer maker and co-founder of Parkinson & Frodsham. Charles showed early promise with two chronometers submitted to the 1830 Premium Trials at Greenwich, one of which was awarded 2nd prize. Nine further chronometers by Charles were entered to the Premium trials until they ceased in 1836.
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Also, he specialized in both watches and chronometers, while his foremost jobs were Harvard's astronomical clock and the astronomical regulator which standardized the time for all New England's railroads.
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They were used to set a hack watch for the actual sight, so that no chronometers were ever exposed to the wind and salt water on deck. Winding and comparing the chronometers was a crucial duty of the navigator. Even today, it is still logged daily in the ship's deck log and reported to the Captain before eight bells on the forenoon watch (shipboard noon). Navigators also set the ship's clocks and calendar.
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On 1 October 1840, the firm, known as E. J. Dent, London began its existence at 82 Strand. On 21 March 1842, Dent applied for a Patent, to be entitled "Certain Improvements in Chronometers and other Timekeepers". This Patent covered various designs of compensation balance and the invention of a Remontoire for use in Marine chronometers. In January 1843, Dent opened his second premises, at 33 Cockspur Street, just off Trafalgar Square.
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Paul Ditisheim was instrumental in developing the new generation of chronometers, improving them greatly through his studies on the impact of atmospheric pressure and magnetic fields. He invented the affix balance. Thanks to his inventions, he was able to make the most precise chronometers ever made. By 1903, his watches were awarded by the Kew and Neuchâtel Observatories contests. In 1912, he won the world’s chronometric record of the Royal Kew Observatory.
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They were used in most spring-driven clocks and watches from their first appearance until the 19th century when the going barrel took over, and in marine chronometers until the 1970s.
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Breitling SA () is a Swiss luxury watchmaker based in Grenchen, Switzerland. The company was founded in 1884 by Léon Breitling in Saint-Imier. Breitling is known for precision-made chronometers designed for aviators.
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In 1767, the Academy of Sciences offered a prize for building a marine chronometer. Le Tellier had a ship build, Aurore, which he used to test the various candidates in real conditions at sea. The expedition also comprised Pingré, Messier and the watchmaker Le Roy, who had built two of the chronometers. Aurore sailed off France, Flander, and Holland in a three-month- and-a-half cruise, sustaining several storms to test whether the chronometers could sustain the movements of the ship.
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Vitally important throughout history, navigational techniques and various pieces of equipment are explained in a small exhibit on the history of navigation at sea. The room is filled with charts, chronometers and meteorological equipment.
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Flinders mainly used the two new Earnshaw's #520 and #546. His other chronometers, Arnold's older #82 and #176, both stopped early in the voyage. K3 was only used by Flinders to chart Wreck Reef.
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Marine chronometers with this type of balance had errors of only 3–4 seconds per day over a wide temperature range. p. 227 By the 1870s compensated balances began to be used in watches.
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The rate of a mechanical marine chronometer is sensitive to its orientation. Because of this, chronometers were normally mounted on gimbals, in order to isolate them from the rocking motions of a ship at sea.
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After having designed plans in 1754, he constructed his first chronometers by 1756, and accomplished his masterpiece in 1766. This remarkable chronometer incorporated a detached escapement, a temperature- compensated balance and an isochronous balance spring, innovations which would be adopted in subsequent chronometers. Harrison demonstrated a reliable chronometer at sea, but these developments by Le Roy are considered by Rupert Gould to be the foundation of the modern chronometer. Pierre Le Roy's chronometer had a performance equivalent to that of the Harrison H4 chronometer.
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The most accurate balance wheel timepieces made were marine chronometers, which were used on ships for celestial navigation, as a precise time source to determine longitude. By WWII they had achieved accuracies of 0.1 second per day.
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Most of the chronometers that came in first in the annual Greenwich Observatory trials between 1850 and 1914 were auxiliary compensation designs.Gould 1923, pp. 265–266 Auxiliary compensation was never used in watches because of its complexity.
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While based in Indiana, students were taught the art of making high grade chronometers and fine lever watches from raw material. Engraving and optician's work, were also taught, and pupils were required to master every detail of the work. After the move to Illinois, the object of the institute was not to make money, but to turn out competent watchmakers and jewelers. The institute gave the student a thorough education in horology, including instructions in making watches, chronometers, clocks and horological machinery in general, as well as repairing the same.
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In the world of mechanical timepieces, accuracy is paramount. In the times before electronics, mechanical timepieces called marine chronometers were developed to a very high degree of accuracy for use in maritime navigation. To test the accuracy of such marine chronometers, watchmakers looked to a phalanx of astronomical observatories located in Western Europe to conduct assessments of timepieces. The observatory staff, applying a slate of accuracy tests, would either reject a timepiece as inaccurate, or, if it passed the stringent testing, would certify it as an observatory chronometer.
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122 John Arnold also invented a similar escapement in 1782. In 1805, Earnshaw and Arnold were granted awards by the Board of Longitude for their improvements to chronometers; Earnshaw received £2500 and John Arnold's son John Roger Arnold received £1672. The bimetallic compensation balance and the spring detent escapement in the forms designed by Earnshaw have been used essentially universally in marine chronometers since then, and for this reason Earnshaw is generally regarded as one of the pioneers of chronometer development. Although he was principally a watchmaker, he did not shy away from building clocks.
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Although both chronometers and lunar distances had been shown to be practicable methods for determining longitude, it was some while before either became widely used. In the early years, chronometers were very expensive, and the calculations required for lunar distances were still complex and time consuming, in spite of Maskelyne's work to simplify them. Both methods were initially used mainly in specialist scientific and surveying voyages. On the evidence of ships' logbooks and nautical manuals, lunar distances started to be used by ordinary navigators in the 1780s, and became common after 1790.
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He presented two new models in 1723. In 1726, he published Une Horloge inventée et executée par M. Sulli. His chronometers performed well in calm weather, but not on the high seas.Encyclopedia of time Samuel L. Macey p.
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These are made of the same optical glass used by the Hubble telescope. In 2017 Jan Frydrych teamed with Thomas Mercer company to create an exclusive range of marine and table chronometers. Mr. Jan Frydrych's optical glass sculpture.
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Kipton was the site of a famous train wreck on April 18, 1891, which was caused by railroad engineers' watches not being in sync; and led to the adoption of stringent quality-control standards for railroad chronometers in 1893.
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63-69 The normal fusee can only be wound in one direction. Drunken fusees were developed, but rarely used, to allow the fusee to be wound in either direction. John Arnold unsuccessfully used them in a few marine chronometers.
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In 1852, it was established to distribute a time signal by the telegraph wires also. The time ball was extremely popular with the public, chronometers, railways, mariners, and there was a petition to have another time ball established in Southampton also.
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Quartz chronometers designed as time standards often include a crystal oven, to keep the crystal at a constant temperature. Some self-rate and include "crystal farms", so that the clock can take the average of a set of time measurements.
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Journal of Experimental Marine Biology and Ecology 14, 179-199. following pioneering work on nuclear test atolls by Knutson and BuddemeierKnutson, D. W., Buddemeier, R. W., and Smith, S. V. 1972. Coral Chronometers: Seasonal Growth Bands in Reef Corals. Science 177, 270-272.
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Since 1999 they have produced a huge range of pilot watches in new sizes, and many COSC certificated chronometers. Zeno also makes diving watches used by the Swiss Army for their frogmen, with models rated for up to 300 meters (1000 feet) depth.
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Dent's chronometers accompanied some of the 19th century's most influential explorers. Robert FitzRoy took Dent chronometer no. 633 aboard HMS Beagle in 1831Mercer, Vaudrey (1977). The Life and Letters of Edward John Dent, Chronometer Maker and some account of his Successors, p.
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The custom of firing a gun daily at 1pm began in 1906 to enable sailors to set their ship's chronometers correctly. The daily gun continued until World War II when the authorities stopped it for fear of alarming residents. The practice recommenced in 1986.
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Nonetheless, for many years even towards the end of the 18th century, chronometers were expensive rarities, as their adoption and use proceeded slowly due to the high expense of precision manufacturing. The expiry of Arnold's patents at the end of the 1790s enabled many other watchmakers including Thomas Earnshaw to produce chronometers in greater quantities at less cost even than those of Arnold. By the early 19th century, navigation at sea without one was considered unwise to unthinkable. Using a chronometer to aid navigation simply saved lives and ships—the insurance industry, self- interest, and common sense did the rest in making the device a universal tool of maritime trade.
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On 29 October 1771, under Lieutenant Verdun de la Crenne, Flore departed Brest for a scientific voyage intended to test several Marine chronometers: Berthoud's n°8, Le Roy's watches A and S, and another called "petite ronde" which was not competing for the 1773 prize, as well as further chronometers by Arsandeaux and Biesta. Borda and Pingré were part of the expedition. Flore called Cadiz and Tenerriffe, before continuing on to Gorée, Fort Royal, Cap français, Saint-Pierre et Miquelon, and Copenhagen, before returning to Brest. Flore took part in the War of American Independence under Castellane-Majastre, ferrying letters between Toulon and America in April 1778.
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At the 1862 International Exhibition in London, Ulysse Nardin was awarded the Prize Medal in the category of "complicated watches and pocket chronometers" . The prize was the highest distinction for watchmaking in the United Kingdom. In 1867, Ulysse Nardin obtained the first series of certificates from Neuchâtel Observatory for its marine chronometers. In 1876, Ulysse Nardin died at age 53, and his son Paul-David Nardin succeeded him as the head of the company which continued to expand. In 1889, Ulysse Nardin won a Gold Medal at the Paris Universal Exhibition, was awarded two Swiss patents in 1890, won First Prize at the Chicago Universal Exhibition in 1893, and many more.
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He took part in a one-year sea campaign to test Berthoud's first marine chronometer, in an attempt to beat Britain in the race to find a reliable way to calculate longitude. The chronometers he thus refined with Ferdinand Berthoud for their later experiments were the object of major struggles with the king's horologer, Pierre Le Roy. Finally Claret de Fleurieu and Berthoud were entrusted with the task, setting out on the testing expedition from autumn 1768 to 11 October 1769 on the corvette Isis under Fleurieu's command. The chronometers almost invariably indicated the hour as accurately after the ship had left port, as if they were still on land.
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Daniels brought his desire to industrialize his escapement to many Swiss manufacturers and he was ultimately denied. Omega in 1999 took on Daniels design with the insight of Nicolas Hayek who saw Omega as a brand of innovation and creativity who would rise to the top of the Swiss horological spectrum with the production of the co-axial escapement. He was right and Omega is one of the largest Swiss manufacturers and the second largest producer of COSC Officially Certified Chronometers, next to Rolex with Breitling being third, with every one of their movements COSC chronometers. The first co-axial movement to be brought to the public was the Omega cal.
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It is almost certain Richard Rippon had worked for them, and had introduced Dent to the firm.Mercer, Vaudrey (1977). The Life and Letters of Edward John Dent, Chronometer Maker and some account of his Successors, p.17, The Antiquarian Horological Society. . In 1826 Dent submitted two chronometers, Nos.
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Mourelle's map and journal named the island El Gran Cocal ('The Great Coconut Plantation'); however, the latitude and longitude was uncertain. Longitude could only be reckoned crudely as accurate chronometers were available until the late 18th century. Visits to the islands became more frequent in the 19th century.
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Longitude presents the story of Harrison's efforts to develop the marine chronometer and thereby win the Longitude prize in the 18th century. This is interwoven with the story of Gould, a retired naval officer, who is restoring Harrison's four chronometers and popularises his achievements in the early twentieth century.
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Kendall was a first-class craftsman but not a technical designer. After K3 Kendall built chronometers to the design of John Arnold. His home was Furnival's Inn Court, London, where he died on 22 November 1790. He was buried on 28 November in the Quaker burial ground in Kingston.
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Jürgensen was also the first in Denmark to make cylindrical wheels in steel instead of brass. Jürgensen continued the workshop alone after his father's death in 1811. Over a twenty-year period, he only manufactured around fifty chronometers. In 1815, he was elected for the Academy of Sciences.
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Ulysse Nardin SA is a Swiss luxury watchmaking company founded in 1846 in Le Locle, Switzerland. The company became known in the nautical world for manufacturing highly accurate marine chronometers and complicated timepieces used by over fifty of the world's navies from the end of the 19th century till 1950. According to the last official report of Neuchâtel Observatory in Switzerland, Ulysse Nardin had won numerous awards and honors for its marine chronometers from 1846 to 1975, including 4324 certificates, 2411 special prizes and 18 gold medals at International Exhibitions. The company was later taken over and re-invigorated in 1983 by Rolf W. Schnyder who transformed it into a profitable business again.
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In 1902, the company started to deliver marine chronometers to the US Navy. The brand regularly won Washington Naval Observatory competitions and became the official supplier for the US Navy's torpedo boats. The company has since provided timepieces to the navies of the United States, United Kingdom, Russia and Japan.
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In 1973, Tallon set up the agency Design Programmes. Brother-in- arms with the LIP watchmakers, he created the Mach 2000 brand of watches and chronometers. In 1974, with Jean-Charles de Castelbajac, he created a concept aircraft cabin for Air France. After leaving Euro RSCG, he continued to work independently.
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After the Civil War, the company became the main supplier of railroad chronometers to various railroads in North America and more than fifty other countries. In 1876, the company showed off the first automatic screw making machinery and obtained the first Gold Medal in a watch precision contest at the Philadelphia Centennial Exposition.
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There are numerous devices for recording the amount of mainspring power stored in the barrel. Power reserve indicators were employed very early on marine chronometers and later in the accurate Railroad grade pocket watches. Today they are used in wrist watches. The first wristwatch with the mechanism was created by Breguet in 1933.
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1 At the request of the manufacturer, a rate bulletin can be obtained in complement to the Geneva seal. 2 Criteria of obtaining a rate bulletin are defined according to the NIHS standard 95-11 ( a/k/a ISO 3159) for chronometers. 3 These bulletins are obtained through the Geneva office of COSC.
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In 1912, he visited Poland, Hungary and the Netherlands with his finest creations. Chopard chronometers and watches marked the passing of time at the court of Nicholas II of Russia. Louis-Ulysse Chopard had won himself an international clientele. In 1859 and 1870 he had two children, Paul-Louis and Ida Hélène.
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This is followed by nautical devices such as compasses, chronometers and sextants. Although displaced by modern technology such as GPS, these devices are still mandatory on board. If they fail or do not work correctly, threaten penalties. Furthermore, nautical charts and logarithm tables are needed to determine the exact position of the ship.
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In total, it cost 1200 piastres. During that time, Rezanov stayed with merchant Armstrong, and Horner stayed with the governor of the island, taking chronometers and observational instruments with him. The observatory was placed in the tower of the Palace of the Inquisition. Then astronomer together with Levenstern and Bellingshausen filmed the Santa Cruz harbor.
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In 1960, the Inchbald School of Design was founded in the basement by his wife Jacqueline Ann Duncan (then Jacqueline Inchbald). The Inchbald School was founded in the old ground floor drawing room, which once housed the Ilbert Collection of clocks, watches, marine chronometers and sundials. It has been Grade II listed since 1969.
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It was taken back to England by Inman. All three of Kendall's chronometers had been to Australia by August 1788, one of them twice. K3 is also now kept at the Royal Observatory, Greenwich. In 1978 K3 was taken to Canada to be part of "Discovery 1778", an exhibition at the Vancouver Centennial Museum.
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No fixed point optical sensors for distance/speed calculations, chronometers or hand-held devices were used, and later with a theoretical calculation, of the distance he traveled in 26 seconds on the bridge. Cycle World's Kevin Cameron had calculated two years earlier that with the right gearing, the H2R's engine power could theoretically overcome aerodynamic drag up to .
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Since 2014, it has been a subsidiary of the French Kering Group. Ulysse Nardin has operated out of the same building headquartered in Le Locle, Switzerland since 1865. The company today designs and manufactures luxury watches, dual time watches, marine chronometers, and sells its products through a network of distributors and several boutiques around the world.
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This established the Board of Longitude and offered large financial rewards for anyone who could find a method of determining longitude accurately at sea. After many years, the consequence of the Act was that accurate marine chronometers were produced and the lunar distance method was developed, both of which became used throughout the world for navigation at sea.
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Thomas Hannaford Hurd (bapt. 30 January 1747 – 29 April 1823) was an officer of the Royal Navy, who rose to the rank of captain, becoming the second Hydrographer of the Navy, a Superintendent of Chronometers and a Commissioner on the Board of Longitude. Hurd Peninsula is named after him due to his role in the discovery of Antarctica.
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Thomas Wright "Watch or Timekeeper" G.B. Patent No.2489 25/4/1783.Pages 13 - 14 "An Appeal to the public" Thomas Earnshaw British Horological Institute reprint 1986. . Eventually, after much argument, the Board of Longitude granted Earnshaw and Arnold awards for their improvements to chronometers. Earnshaw received £2500 and John Arnold's son, John Roger Arnold, received £1672.
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Once hewn the stone was delivered on large wagons drawn by six oxen. In the second half of the 17th century his son Paul further extended and ornamented the castle with architect Domenico Carlone. After Paul's death the castle's function changed. It became a repository for weapons, archives, chronometers, machines, exotic animal preparations and other "marvels".
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In 1945 they moved again to Prospect Place in Lenton, where the company remained until it was absorbed by Smith of Derby Group. The company was responsible for most of the public clocks in Nottingham, and also many further afield. As innovative manufacturers, the firm produced chronometers for the Admiralty as well as fine tower clocks and chimes.
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In this case, the watch is started at a known GMT by chronometer, and the elapsed time of each sight added to this to obtain GMT of the sight. All chronometers and watches should be checked regularly with a radio time signal. Times and frequencies of radio time signals are listed in publications such as Radio Navigational Aids.
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The Industrial Revolution changed the area greatly. It became a centre for breweries, distilleries and the printing industry. It gained an especial reputation for the making of clocks, marine chronometers and watches, which activity once employed many people from around the area. Flourishing craft workshops still carry on some of the traditional trades, such as jewellery-making.
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During the nineties, the Mido World Timer was launched. This was a practical display that can show the local time anywhere on the planet. The user must bring the desired city to the 12 o’clock position and press the crown to check the local time. Mido is recognized as one of the top 10 producers of certified chronometers.
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The problem of longitude measurement had been at the heart of astronomical research for a century or more, and marine chronometers were steadily becoming more accurate. Chappe and physicist Henri-Louis Duhamel du Monceau (1700–82) were selected to test one such chronometer, made by Swiss watchmaker Ferdinand Berthoud (1727–1807) on board the corvette L'Hirondelle in 1764.
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In addition to the aforementioned port hailing duties, the guns have had the task of firing a time signal since 1806. According to local tradition, the initial purpose of the gun was to allow ships in port to check the accuracy of their marine chronometers (a precision instrument used aboard ships to help calculate longitude). The gun report might be too inaccurate for ships several kilometers away if they did not correctly compensate for the relatively slow speed of sound. For this reason, ships marked their time by the puff of smoke rather than the sound, and this is one reason the guns are sited high above Cape Town Harbour. The invention of the more accurate time ball in 1818 soon made time guns redundant for mariners wishing to set their chronometers.
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With the lunar distance method, mariners could determine their longitude accurately. Once chronometer production was established in the late 18th century, the use of the chronometer for accurate determination of longitude was a viable alternative. Chronometers replaced lunars in wide usage by the late 19th century. In 1891 radios, in the form of wireless telegraphs, began to appear on ships at sea.
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Under orders to gather information before going to Cochin-China, Peacock sailed for Manila by way of Long Island and 'Crokatoa' (Krakatoa), where hot springs found on the eastern side of the islands one hundred and fifty feet from the shore boiled furiously up, through many fathoms of water. Her chronometers proving useless, Peacock threaded the Sunda Strait by dead reckoning.
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Enjouée was tasked with testing one of the first marine chronometers, by Pierre Le Roy, to ascertain whether it allowed measurements of longitude precise enough for navigation, after preliminary testing on Aurore. The test was successful and Le Roy was awarded a prize in recognition of his invention.Delacroix, p. 12 Enjouée was hulked at Brest in 1777 and broken up in 1783.
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Hans Momsen (born 23 October 1735, Fahretoft – 13 September 1811, ibidem) was a North Frisian farmer, mathematician and astronomer. Entirely without university studies he was able to solve complicated mathematical calculations and to construct astronomical devices, chronometers and other apparatus. He gave lessons in mathematics to gifted students. Moreover, he worked as a surveyor and built an organ for the church of Fahretoft.
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These activities depended on astronomical observation to determine location and direction, observations which were notoriously difficult in the cloudy and variable weather of the Bering Sea. The Plover Bay visits of 1880 served to recalibrate marine chronometers against the known longitude of that location. Marcus Baker was the astronomical observer for all three trips. Another focus was the collection of biological specimens.
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Jürgensen returned to Copenhagen in 1801. He was supposed to enter into a partnership with a French watchmaker, Etienne Magnin, who had been called to Denmark to construct the next chronometers for the shipping industry. These plans changed when watchmaker continued to Saint Petersburg and Jürgensen then joined his father's workshop. In 1804, he published Regler for Tidens nøjagtige Afmaaling ved Uhre.
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That was when Japanese watch manufacturers such as Seiko and Citizen rose to dominance due to their pioneering of quartz movement. In response, Rolex continued concentrating on its expensive mechanical chronometers where its expertise lay (though it did have some experimentation in quartz), while Omega tried to compete with the Japanese in the quartz watch market with Swiss made quartz movements.
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Together with telescopic instruments, they would revolutionize observational astronomy and cartography in the coming years. Huygens was also the first to use a balance spring as oscillator in a working clock, and this allowed accurate portable tme-pieces to be made. But it was not until the work of Harrison that such clocks became accurate enough to be used as marine chronometers.
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Other makers in particular Thomas Earnshaw, who developed the spring detent escapement, simplified chronometer design and production. As chronometers became more affordable and reliable, they tended to displace the lunar distance method between 1800-1850. An 1814 chart showing part of South Australia including Port Lincoln. Based on Flinders' survey of 1801-2Chronometers needed to be checked and reset at intervals.
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He proceeded along the south coast, using chronometers to determine longitude of the features along the way. Arriving at the bay he named Port Lincoln, he set up a shore observatory, and determined the longitude from thirty sets of lunar distances. He then determined the chronometer error, and recalculated all the longitudes of the intervening locations. Ships often carried more than one chronometer.
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After his return to England following the conclusion of the war, Lindsay received a knighthood on 10 February 1764. Lindsay returned to the West Indies, in command of the Tartar. His ship carried one of John Harrison's chronometers for tests and Thomas Erskine was serving as one of his midshipmen.Thomas Erskine, Electric Scotland He returned to Britain in 1765, following the conclusion of the war.
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9, p. 152-166.Dunkley, D.J., Suzuki, K., Hokada, T., Kusiak, M.A., 2008, Contrasting ages between isotopic chronometers in granulites: Monazite dating and metamorphism in the Higo Complex, Japan, Gondwana Research, . and Paleogene Gruf Complex, central Alps.Droop, G. T. R., and Bucher-Nurminen, K., 1984, Reaction textures and metamorphic evolution of sapphirine-bearing granulites from the Gruf Complex, Italian Central Alps: Journal of Petrology, v.
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Ferdinand Berthoud (18 March 1727, in Plancemont-sur-Couvet (Principality of Neuchâtel) – 20 June 1807, in Groslay (Val d'Oise)), was a scientist and watchmaker. He became master watchmaker in Paris in 1753. Berthoud, who held the position of Horologist-Mechanic by appointment to the King and the Navy, left behind him an exceptionally broad body of work, in particular in the field of sea chronometers.
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Watchmaking began to replace agriculture and lace making as the main industries. By the end of the 18th Century the city employed about 500 lace makers. Le Locle was home to a number of famous watchmakers and inventors, including Abraham-Louis Perrelet, Jacques-Frédéric Houriet, Frédéric-Louis Favre-Bulle and David-Henri Grandjean. In the 19th century the town was known for its pocket and marine chronometers.
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As the son of a Swiss horologist, Guillaume took an interest in marine chronometers. For use as the compensation balance he developed a slight variation of the invar alloy which had a negative quadratic coefficient of expansion. The purpose of doing this was to eliminate the "middle temperature" error of the balance wheel. The Guillaume Balance (a type of balance wheel) in horology is named after him.
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The fact that Arnold had recognized the technical advantages of a balance spring of this form clearly demonstrates a high degree of insight. The balance that was the subject of the patent appears to have been an unsuccessful design. Certainly, some marine chronometers used this balance, but none have survived. Pearson records a balance of this kind in his possession that was 2.4 inches in diameter.
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There are five types of rolling elements that are used in rolling-element bearings: balls, cylindrical rollers, spherical rollers, tapered rollers, and needle rollers. Most rolling-element bearings feature cages. The cages reduce friction, wear, and bind by preventing the elements from rubbing against each other. Caged roller bearings were invented by John Harrison in the mid-18th century as part of his work on chronometers.
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Connell was born in London in 1875 to Frederic and Catherine Connell. Her father (and his father) had made high-class watches known as chronometers, but her father's interest moved to photography before he became a salesperson. The photography business made his daughters Dora and Alina into photographer's assistants and Adelina/Lena's career path was decided. Cicely Hamilton was a leading campaigner and they worked together.
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A new approach to test evidence of dark energy through observational Hubble constant data (OHD) has gained significant attention in recent years. The Hubble constant, H(z), is measured as a function of cosmological redshift. OHD directly tracks the expansion history of the universe by taking passively evolving early-type galaxies as “cosmic chronometers”. From this point, this approach provides standard clocks in the universe.
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Accurate time was important for navigation, and mariners would bring ships' chronometers from the port of Leith up to Calton Hill for adjustment. In 1854 the time ball was installed on Nelson's Monument next to the observatory and visible from the port. This was controlled by electrical pulses from the observatory clock. A few years later the One O'Clock Gun on Edinburgh Castle was added.
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During his tenure of office he was responsible for testing thousands of chronometers, watches, thermometers and other scientific instruments, success in which tests gained the award of a "Kew Certificate". Chree received degrees of D.Sc. from Cambridge in 1895 and LL.D. from Aberdeen in 1898. The Chree Medal and Prize of the Institute of Physics was named for him. The awards were renamed in 2008.
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At first Nansen and Johansen made good progress south, but suffered a serious setback on 13 April, when in his eagerness to break camp, they had forgotten to wind their chronometers, which made it impossible to calculate their longitude and accurately navigate to Franz Josef Land. They restarted the watches based on Nansen's guess they were at 86°E. From then on were uncertain of their true position.Fleming, p. 249.
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The long stay in the Danish capital led to the first conflicts between Krusenstern and Rezanov. According to diaries by Levenstern and Ratmanov, the ambassador and his court advisor Fosse regularly attended brothels without taking away their regales and orders. Count Tolstoy even got an "illness which is characteristic for his age". From August 21 to September 4, a reconciliation of ship chronometers was carried out at the Copenhagen Observatory.
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The detent or chronometer escapement is considered the most accurate of the balance wheel escapements, and was used in marine chronometers, although some precision watches during the 18th and 19th century also used it.Milham 1945, p.235 The early form was invented by Pierre Le Roy in 1748, who created a pivoted detent type of escapement, though this was theoretically deficient.Britten's Watch & Clock Makers' Handbook Dictionary & Guide Fifteenth Edition p.
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On the voyage from Muscat to Mozambique, Roberts omitted the particulars of each day, but stated that what he had written served "to show the absolute necessity of having first-rate chronometers, or the lunar observations carefully attended to; and never omitted to be taken when practicable." Peacock returned Roberts to Rio de Janeiro on 17 January 1834, where on 1 March 1834 he boarded Lexington to return to Boston.
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The first successful marine chronometers, H4 and H5, made by John Harrison in 1759 and 1770, used verge escapements with diamond pallets., Perez 2001 , pp.11Hird, Jonathan R., Betts, Jonathan D. & Pratt, D. The Diamond Pallets of John Harrison's Longitude Timekeeper–H4. Annals of Science, volume 65, Issue 2, April 2008, pg 171-200 In trials they were accurate to within a fifth of a second per day.
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Born in 1918, Gould was the son of Rupert Gould, the restorer of John Harrison’s chronometers, and Muriel Estall. Gould was educated at Kingswood House preparatory school, near Epsom, and then at Westminster School. After leaving school he studied at the Courtauld Institute. During the Second World War he served as Pilot Officer Gould in R.A.F. Intelligence, first in Egypt from 1941 to 1943 and then in Normandy, France.
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Royal Observatory, Greenwich, London. Installed in 1833, a time ball sits atop the Octagon Room A time ball or timeball is an obsolete time-signalling device. It consists of a large, painted wooden or metal ball that is dropped at a predetermined time, principally to enable navigators aboard ships offshore to verify the setting of their marine chronometers. Accurate timekeeping is essential to the determination of longitude at sea.
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Murray Islands is a group of small islands southeast of Cape Whitson, off the south coast of Laurie Island in the South Orkney Islands. Discovered in 1823 by Matthew Brisbane, who explored the south coast of Laurie Island under the direction of James Weddell. The name "Murrys Islands" appears on Weddell's chart, but the islands are probably named for James Murray of London, maker of the chronometers used on Weddell's voyage.
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Borda was born in the city of Dax to Jean‐Antoine de Borda and Jeanne‐Marie Thérèse de Lacroix. In 1756, Borda wrote Mémoire sur le mouvement des projectiles, a product of his work as a military engineer. For that, he was elected to the French Academy of Sciences in 1764. Borda was a mariner and a scientist, spending time in the Caribbean testing out advances in chronometers.
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As the Germans closed in on Moscow in 1941, the factory was hurriedly evacuated to Zlatoust (). By 1943 the Germans were in retreat, and the factory moved back to Moscow, adopting the "First Moscow Watch Factory" name (). In 1947 the first wristwatches under the brand name "Pobeda" and the first Marine Chronometers and Deck watches were produced. By 1951 the production of wristwatches had increased to 1.1 million.
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These techniques aimed to represent illusory inner architectural spaces and the so-called fourth dimension. These images are, for purposes of lucidity, mostly composed of basic geometric forms such as spheres, cylinders, cubes, and cones. Simultaneously the viewer is able to view the objects according to their own perspective, depending on various angles of observation and the play of light. In last years Frydrych also creates custom chronometers.
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On short voyages between places of known longitude this was not a problem. For longer journeys, particularly of survey and exploration, astronomical methods continued to be important. An example of the way chronometers and lunars complemented one another in surveying work is Matthew Flinders' circumnavigation of Australia in 1801-3. Surveying the south coast, Flinders started at King George Sound, a known location from George Vancouver's earlier survey.
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He gained permission in 1920 to restore the marine chronometers of John Harrison, and this work was completed in 1933. His horological book The Marine Chronometer, its history and development was first published in 1923 by J.D. Potter and was the first scholarly monograph on the subject. It was generally considered the authoritative text on marine timekeepers for at least half a century. Gould had many other interests and activities.
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Clockmakers William Potts & Sons, Leeds were established in 1833 and acquired by Smith of Derby in 1933; J. B. Joyce & Company of Whitchurch were responsible for many clocks internationally and were acquired by Smith of Derby in 1965; George & Francis Cope were established in 1845 as producers of chronometers for the Admiralty, and joined Smith of Derby in 1984. In 1985 they acquired B & H (Derby) Ltd and became the current Smith of Derby Group.
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The Rolex Milgauss series of antimagnetic certified chronometers was first manufactured in 1954 with the model 6541 for those working in nuclear, aircraft, and medical settings associated with strong magnetic fields. The watch has an advertised magnetic flux density resistance of 1 000 gauss within magnetic fields of 80 000 A/m. In 2007, after being out of production for nearly two decades a new Milgauss was introduced as the model number 116400.
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Nonetheless, this escapement became the standard in precision regulator clocks until late in the nineteenth century. Because of its various idiosyncrasies, the grasshopper escapement was never used widely. Harrison used it in his prototype marine chronometers, H1 - H3, and Justin and Benjamin Vulliamy made a small number of regulators using Harrison's design,Betts, Jonathan; Regulator Clock in but generally it remains today what it was in Harrison's time: a brilliant, unique curiosity.
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By 1948, the company was focusing on sporty chronographs that prominently displayed the current date. Carl Friedrich Bucherer's first boutique in Lucerne, Switzerland. By 1968, Carl F. Bucherer had manufactured around 15,000 high-precision, certified chronometers, making the company one of the top three Swiss producers of these specialized timepieces. In 1969, the company became part of a Swiss consortium for the development and production of the first quartz movement for wristwatches, the Beta 21.
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The next section listed Familiar Lifeforms: composed of intelligent species with many of them dangerous and hostile. The list concluded with a set of randomly entered tables for the creation of new monsters with which to entertain the players. Next the equipment listing contained variations on the devices already noted in the basic rules equipment section. There were many weapons, some protective devices, and a few gadgets such as belt lights, chronometers, and advanced tricorders.
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The dock was designed by Jesse Hartley and opened in 1834 as Waterloo Dock, named after the Battle of Waterloo. In 1843 an observatory was built here for astronomical and meteorological observations and to provide accurate time for ships' chronometers. In 1866, when the dock was redeveloped, the observatory was relocated to Bidston Hill on the Wirral Peninsula. In 1868, Waterloo Dock was split in two separate basins; East Waterloo Dock and West Waterloo Dock.
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A timeball apparatus mounted on top of the bluestone tower operated regularly until 1926. Its original use was as a signalling device to ships. From 1858 until 1926 the large ball on the top was dropped each afternoon at one o'clock to allow shipmasters moored offshore to correct their chronometers. The Timeball Tower/Lighthouse had an additional time signal at eight o'clock each night by means of eclipsing the lantern of the lighthouse.
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As Astronomer Royal, Pond was responsible for a substantial modernisation of the Observatory at Greenwich, extending from equipment improvements to new working practices. Perhaps his most noticeable addition was the 1833 installation of the time ball on the roof of the Observatory. Arguably, the first public time signal in the UK, the ball's drop occurs daily at 1:00 p.m. and was intended to aid mariners on the Thames to synchronise their marine chronometers.
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In 1947 he was awarded the Gold Medal of the British Horological Institute, its highest honour for contributions to horology. Gould died on 5 October 1948 at Canterbury, Kent, from heart failure. He was 57 years of age. Longitude, a television dramatisation of Dava Sobel's book Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time, recounted in part Gould's work in restoring the Harrison chronometers.
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The transit circle was capable of determining both right ascension and declination of a star, unlike the more simple and common transit instrument that can only determine the right ascension. Such an instrument could also be used to set the Observatory's clocks by observing standard stars whose position was precisely known. In addition there were three other smaller transit telescopes, two clocks by Clemens Riefler of Munich, and other accessories including sextants, chronometers, and teaching tools.
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Both analog and digital temperature compensation have been used in high-end quartz watches. In more expensive high-end quartz watches, thermal compensation can be implemented by varying the number of cycles to inhibit depending on the output from a temperature sensor. The COSC average daily rate standard for officially certified COSC quartz chronometers is ±25.55 seconds per year at 23 °C. To acquire the COSC chronometer label, a quartz instrument must benefit from thermo-compensation and rigorous encapsulation.
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In 1795, the post of Hydrographer of the Navy was created. He became responsible to the First Naval Lord for producing charts, 'Sailing Directions', 'Notices to Mariners', tide tables and light lists and for supplying chronometers, compasses and other scientific instruments to HM ships. He was also responsible for naval meteorology and for the Admiralty's links with the Meteorological Office. In 1820, the Hydrographer was responsible for the Observatory, being advised by a Board of Visitors.
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18, The Antiquarian Horological Society. . In a letter to the Board of Ordnance, dated March, 1829, John Pond – at the time Astronomer Royal – described Dent as "among the best workmen of the present day." Dent's reputation for precision eventually brought requests from the Admiralty and the East India Company. His reputation was given another boost when, in August, 1829, Dent Marine Chronometer No. 114 won the First Premium Award at the Seventh Annual Trial of Chronometers.
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Arnold's pattern first appeared in 1783, on the enamel dials Arnold designed for his small chronometers, and the proportions and layout of their figuring is identical to that of the classic "Breguet" type of engine- turned metal dials which appeared around 1800, and which were quite unlike anything else made in France or Switzerland at the time.Hans Staeger 1997 - 100 years of Precision Timekeepers from John Arnold to Arnold & Frodsham 1763 - 1862. Private Publication. See Page 164 Fig.
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For most of history, mariners struggled to determine longitude. Longitude can be calculated if the precise time of a sighting is known. Lacking that, one can use a sextant to take a lunar distance (also called the lunar observation, or "lunar" for short) that, with a nautical almanac, can be used to calculate the time at zero longitude (see Greenwich Mean Time). Reliable marine chronometers were unavailable until the late 18th century and not affordable until the 19th century.
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Dionisio Alcalá Galiano (8 October 1760 - 21 October 1805) was a Spanish naval officer, cartographer, and explorer. He mapped various coastlines in Europe and the Americas with unprecedented accuracy using new technology such as chronometers. He commanded an expedition that explored and mapped the Strait of Juan de Fuca and the Strait of Georgia, and made the first European circumnavigation of Vancouver Island. He reached the rank of brigadier and died during the Battle of Trafalgar.
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Brown may have been planning to take over the post, but instead did not establish any post. Later in the year Brown had a violent conflict with the indigenous people of Clayoqout Sound as well. He claimed he acted in self-defense, while other fur traders said he forcefully stole furs from the Clayoquot people. On 18 and 28 May the Spanish made an observation of the moons of Jupiter, allowing them to finely calibrate their chronometers.
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Half a degree of longitude is equivalent to two minutes of time, so the required accuracy is a few seconds a day. At that time, there were no clocks that could come close to maintaining such accurate time while being subjected to the conditions of a moving ship. John Harrison, a Yorkshire carpenter and clock-maker believed it could be done, and spent over three decades proving it. Harrison built five chronometers, two of which were tested at sea.
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Fine regulation and chronometer characteristics of a watch can be destroyed in seconds by a rough and inexperienced hand.F. von Osterhausen, Wristwatch Chronometers: Mechanical Precision Watches and Their Testing (Schiffer; 2ed., Atglen, 1997), at page 28, table 38; page 59. Considering the fact that mechanical watches are almost never used for real timekeeping and navigation anymore, certification may be considered a historic relic by some, but it verifies the accuracy and quality of a mechanical movement.
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The considerably more popular method was (and still is) to use an accurate timepiece to directly measure the time of a sextant sight. The need for accurate navigation led to the development of progressively more accurate chronometers in the 18th century (see John Harrison). Today, time is measured with a chronometer, a quartz watch, a shortwave radio time signal broadcast from an atomic clock, or the time displayed on a GPS. A quartz wristwatch normally keeps time within a half- second per day.
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The Noon gun in Cape Town still fires an accurate signal to allow ships to check their chronometers. Many buildings near major ports used to have (some still do) a large ball mounted on a tower or mast arranged to drop at a pre-determined time, for the same purpose. While satellite navigation systems such as the Global Positioning System (GPS) require unprecedentedly accurate knowledge of time, this is supplied by equipment on the satellites; vehicles no longer need timekeeping equipment.
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In the early 1850s, the facility began performing a role in assessing and rating barometers, thermometers, chronometers, watches, sextants and other scientific instruments for accuracy; this duty was transferred to the National Physical Laboratory in 1910. An instrument which passed the tests was awarded a "Kew Certificate", a hallmark of excellence. As marine navigation adopted the use of mechanical timepieces, their accuracy became more important. The need for precision resulted in the development of a testing regime involving various astronomical observatories.
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The oldest method of determining the lunar distance involved measuring the angle between the Moon and a chosen reference point from multiple locations, simultaneously. The synchronization can be coordinated by making measurements at a pre-determined time, or during an event which is observable to all parties. Before accurate mechanical chronometers, the synchronization event was typically a lunar eclipse, or the moment when the Moon crossed the meridian (if the observers shared the same longitude). This measurement technique is known as lunar parallax.
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This station had a radio telegraphy range of 80 kilometers with a fleet of 14 ships at sea and with Brest. In 1904 the Ouessant radio station with call sign FFU carried out radiotelegraphic connections on 600 meters with a fleet of passenger ships. From 1905, Tissot made very thorough studies on the detection of radio signals. Following these tests, Tissot showed the possibility of using radio to transmit a time signal and to regulate the chronometers of the ships at sea.
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He published two papers in the Philosophical Transactions for 1824.Of the Effects of the Density of the Air on the Rates of ChronometersExperimental Inquiries Relative to the Distribution and Changes of the Magnetic Intensity in Ships of War They dealt with the accuracy of chronometers and the magnetic compass. A paper by Harvey on colour blindness from 1824.On an Anomalous Case of Vision with regard to Colours, has been regarded as pioneering, for its use of a table of Patrick Syme.
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31, The Antiquarian Horological Society. . the voyage that eventually led to the publication of On the Origin of Species – Darwin's revolutionary theory of evolution. Two decades later, David Livingstone purchased Dent chronometer no. 1800 for his African explorations. And in 1890, the explorer H.M. Stanley was moved to write to Dent that “the Chronometers supplied by you, and which were taken across Africa in my last Expedition, proved a very great service to me and were in every way thoroughly satisfactory and reliable”.
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The time ball on Signal Hill was used to relay time from the Cape Town Observatory, whose time ball was not visible from all parts of the bay. At precisely 1:30pm Cape Mean Time, the ball would be dropped at the Observatory – an observer on Signal Hill would then drop that more prominent ball too. When setting their chronometers, mariners adjusted their observation of the time ball on Signal Hill by a second to allow for the relay from the observatory.
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A keyboard with trackball is the input device for operation of this system. Two Barco VGA color monitors display camera annotation and other camera data on screen for the sensor operator and observer use. Camera control, located in the sensor operator's console, operates and adjusts individual cameras for cloud cover, frame overlap and other functions. The sensor operator console seats four and has all the equipment listed above plus camera bay heating control, chronometers, emergency oxygen, interphone and individual lighting.
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Pursuant to orders to gather information before going to Cochinchina, Peacock sailed for Manila by way of Long Island and Crokatoa, where hot springs found on the eastern side of the islands from the shore boiled furiously up, through many fathoms of water. Peacocks marine chronometers proving useless, she threaded the Sunda Strait by dead reckoning. Diarrhea and dysentery were prevalent among the crew from Angier to Manila. After a fortnight there, cholera struck, despite the overall cleanliness of the ship.
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A time ball is a large painted wooden or metal ball that drops at a predetermined time, principally to enable sailors to check their marine chronometers from their boats offshore. While latitude has long been easily determined first using an astrolabe and later a sextant, timekeeping is one way of enabling mariners to determine their longitude at sea. The key to this was accuracy, as an error of four seconds translates into of actual distance at the equator, and at latitude 60 degrees.
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In this way ships in the bay were able to check their marine chronometers. The daily practice of dropping of the ball continued until 1934, when it was made redundant by radio signals. The guns on Signal Hill were used to notify the public when a ship was in trouble and there was a possibility of casualties on the coast near Cape Town. Three guns would be fired from Chavonnes Battery, followed by a single gun in answer from Imhoff Battery.
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Draper was an eccentric collector of old coins, swords, pistols and watches. “For anything that might take his fancy, he was not particular as to the price he might pay,” The Times noted after his death. At 8pm every night he would lock himself into his sitting room with his chronometers and a book, staying up all night until the villagers got up at 6am; if he heard a noise outside, he would fire his pistols through an ‘aperture’ in the window.
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Moving the lever slides the slit up and down the balance spring, changing its effective length, and thus the resonant vibration rate of the balance. Since the regulator interferes with the spring's action, chronometers and some precision watches have ‘free sprung’ balances with no regulator, such as the Gyromax. Their rate is adjusted by weight screws on the balance rim. A balance's vibration rate is traditionally measured in beats (ticks) per hour, or BPH, although beats per second and Hz are also used.
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If it is worn constantly, keeping it near body heat, its rate of drift can be measured with the radio and, by compensating for this drift, a navigator can keep time to better than a second per month. Traditionally, a navigator checked his chronometer from his sextant, at a geographic marker surveyed by a professional astronomer. This is now a rare skill, and most harbourmasters cannot locate their harbour's marker. Traditionally, three chronometers were kept in gimbals in a dry room near the centre of the ship.
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Constant Girard was equally interested in the measure of time and he illustrated this in his chronometers watches. Girard-Perregaux were rewarded by several gold medals or diplomas from expositions in Europe and in America for his efforts. Some of its creations are presented at the Girard-Perregaux Museum situated in La Chaux- de-Fonds, Switzerland. Constant Girard also produced the first ever major commercial production of a wristwatch, made for German naval officers and ordered by German Kaiser Wilhelm I for his German naval officers.
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Hans-Jürgen Mühle was still in active operation, and later became sales manager of the Glashütte Watchmaking Plants. The German unification enabled him to revive the company of his ancestors, so in 1994, he founded "Mühle-Glashütte GmbH nautische Instrumente und Feinmechanik" (nautical instruments and precision engineering). At the beginning Mühle produced professional marine chronometers, ship's timepieces and other nautical instruments such as Barometer or hygrometer. Two years later the production was extended to mechanical wristwatches, which quickly became the main business of the company.
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The next day, the consul arranged for the astronomers to use a rocky island called Rados where Simonov, guard-marine Adams and artilleryman Korniliev set a transit instrument and started to reconcile the chronometers. Generally, Bellingshausen was not fond of the Brazilian capital, mentioning "disgusting untidiness" and "abominable shops where they sell slaves". On the contrary, Simonov claimed that Rio with its "meekness of morals, the luxury and courtesy of society and the magnificence of spiritual processions" do "remind him of southern European cities".
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However, 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 the Hudson's Bay Company, and the American Methodist Mission at Point Adams.
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In 1821, with the help of Frederik VI of Denmark, he founded a company in Altona to produce precision watches – this company later became Theodor Knoblich and existed until 1991. Kessels worked on the development of marine chronometers, observation clocks and pendulums for astronomical observatories. He also continued to represent Breguet in northern Germany and Scandinavia and seems to have worked with the British chronometer maker George Muston. In total, 200 to 250 precision watches can be attributed to Kessels, an average of eight per year.
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Pages 3-15 "An Appeal to the public" Thomas Earnshaw British Horological Institute reprint 1986. . In 1780, while making these chronometers for Brockbank, Earnshaw modified the pivoted detent by mounting the locking piece on a spring, thus dispensing with the pivots. Arnold managed to see this new idea and promptly took out the 1782 patent for his own design of spring detent, but it is not known whether this preceded Earnshaw's own idea.Page 3 - "An Appeal to the public" Thomas Earnshaw British Horological Institute reprint 1986. .
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In 1780, he devised a modification to the detached chronometer escapement, the detent being mounted on a spring instead of on pivots. This spring detent escapement was patented by Thomas Wright (for whom he worked) in 1783. Whilst initially the design was crude and unsuccessful, with modifications it later became the standard form in marine chronometers,Details on Earnshaw's spring indent escapement following the invention of the detent escapement by Pierre Le Roy in 1748.Britten's Watch & Clock Makers' Handbook Dictionary & Guide Fifteenth Edition p.
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At the end of the month, the Red Army captured the building. After the region was united with the Ukrainian SSR, the National Academy of Sciences of Ukraine (NASU) sent an expedition. On 31 December 1939 the first academician-astronomer of the Academy of Sciences of the Ukrainian SSR Oleksandr Orlov ascended to the observatory. He established that the most valuable equipment has been taken out of the building, including five lenses of big diameter, two lenses of smaller diameter, two micrometers, and two chronometers.
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It was tested again on a naval frigate, Enjouée, and in 1769 Le Roy was awarded the prize. Further testing of Le Roy's watches took place in 1771 and 1772 with the voyage of Borda and Pingré on Flore, where they tested his chronometers A and S, as well as Berthoud's n°8. Le Roy again won the 1773 double prize. The chronometer went on to be part of the collections of the Conservatoire national des arts et métiers, where it is on display.
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It is doubtful whether adding jewels in addition to the ones listed above is really useful in a watch. It does not increase accuracy, since the only wheels which have an effect on the balance wheel, those in the going train, are already jeweled. Marine chronometers, the most accurate portable timepieces, often have only 7 jewels. Nor does jeweling additional wheel bearings increase the useful life of the movement; as mentioned above most of the other wheels do not get enough wear to need them.
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In particular, Paul Newman's Rolex Daytona currently holds the title of the second most expensive wristwatch and the third most expensive watch ever sold at auction, fetching 17.75 million US dollars in New York on October 26, 2017. Rolex is the largest manufacturer of Swiss made certified chronometers. In 2005, more than half the annual production of watches certified by Contrôle Officiel Suisse des Chronomètres (COSC) were Rolexes. To date, Rolex still holds the record for the most certified chronometer movements in the category of wristwatches.
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McLachlan was born in London on 10 April 1837, one of five children of Hugh McLachlan and Hannah (Thompson) McLachlan. His father was a successful manufacturer of ship chronometers. He lived his early life in Ongar, Essex, and was educated in Ilford at a private school where he developed a good knowledge of English, French and German.DNB, 2004 Due to a sizable inheritance, McLachlan was a man of independent means and devoted himself entirely to the study of entomology and other aspects of natural history.
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Between 1735 and 1760 John Harrison developed four types of marine chronometers for use at sea to allow accurate determination of longitude. The gyrocompass was introduced in 1908 while ship's radar came in after the 1930s. Radar is also used on land for monitoring the position of shipping, for example in the Strait of Dover which is the busiest area of sea in the world. The Decca Navigator System was a hyperbolic radio navigation system that was installed around the coasts of Britain in the 1940s.
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Cited in: See page 56 In 1911 the French determined the difference of longitude between Paris and Bizerte in Tunisia, a distance of 920 miles, and in 1913-14 a transatlantic determination was made between Paris and Washington. The first wireless time signals for the use of ships at sea started in 1907, from Halifax, Nova Scotia. Time signals were transmitted from the Eiffel Tower in Paris starting in 1910. These signals allowed navigators to check and adjust their chronometers on a frequent basis.
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Lieutenant Peter Lecount RN FRAS CE (25 May 1794 - 1852) was a naval officer and a civil engineer with a strong interest in railways. He joined the navy in 1809 and saw active service until going on half-pay in 1827. He was made a Fellow of the Royal Astronomical Society while a midshipman. Between 1820 and 1823 he wrote papers and related letters to the Board of Longitude on clocks and chronometers, celestial navigation, particularly using Jupiter's satellites, and a marine chair for observing them.
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Before good chronometers were available, longitude measurements were based on the transit of the moon, or the positions of the moons of Jupiter. For the most part, these were too difficult to be used by anyone except professional astronomers. The invention of the modern chronometer by John Harrison in 1761 vastly simplified longitudinal calculation. The longitude problem took centuries to solve and was dependent on the construction of a non-pendulum clock (as pendulum clocks cannot function accurately on a tilting ship, or indeed a moving vehicle of any kind).
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They drew on several styles, including the Canterbury scene and the experimental sound of the English avant-rock group Henry Cow. Henry Cow had a big impact on the band – Newhouse said that "Living in the Heart of the Beast" from their album In Praise of Learning "had a tremendous influence on me." During late 1975 and early 1976 the Muffins made a number of studio and home demos, but did not release them. Many, however, were later released on an album Chronometers by Cuneiform Records in 1993.
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Harrison's H4 chronometer of 1761, published in The principles of Mr Harrison's time-keeper, 1767.The principles of Mr Harrison's time-keeper Marine chronometers are clocks used at sea as time standards, to determine longitude by celestial navigation. A major stimulus to improving the accuracy and reliability of clocks was the importance of precise time-keeping for navigation. The position of a ship at sea could be determined with reasonable accuracy if a navigator could refer to a clock that lost or gained less than about 10 seconds per day.
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The revival of the observatory on the Gregorian Tower was initiated by the Barnabite Francesco Denza with the approval of Pope Leo XIII. High quality instruments were procured, partly with generous donations from Hicks of London, and the automatic recording instruments were procured from Richard in Paris. A four- inch equatorial, a three-inch transit instrument, and four pendulum clocks with two chronometers, were also procured from the observatory at Modena. In 1888, the gift of a 16 inch long telescope to Pope Leo XIII, became a part of the observatory.
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Ferdinand Berthoud left behind him an extraordinary output in a variety of fields: sea chronometers, watches and decorative clocks, specialist tools, and scientific measurement instruments, as well as publishing scores of written works and specialist dissertations, totalling over 4,000 pages and 120 copperplates. The titles, privileges, and testimonials of recognition throughout his career, extending from the reign of Louis XV through to the First Empire, as well as the tributes and studies that highlight his critical renown through to the present day, reflect the importance of his place in the long quest for accuracy.
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On 1 August 1785, Ferdinand Berthoud gave five clocks to the captain of the Astrolabe, Lapérouse, as he was leaving on an expedition around the world with the aim of adding to the discoveries of James Cook in the Pacific Ocean. The clocks taken on board were lost at sea in the wreck of the Astrolabe in 1788 off the coast of the Santa Cruz Islands, near the Solomon Islands. In 1791, Berthoud supplied four marine chronometers to Bruni d'Entrecasteaux, to his expedition to search for Lapérouse with the frigates Recherche and Espérance.
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Officers visited the neighborhoods of the city, coffee plantations, and Trizhuk Falls. On November 9, commanders of both divisions – Bellingshausen, Lazarev, Vasiliev, and Shishmaryov – received the audience with the Portuguese king John VI of Portugal, who at that time resided in Brazil. Before the ships departed, their crews filled the stocks and took for slaughtering two bulls, 40 pigs and 20 piglets, several sheep, ducks and hens, rum and granulated sugar, lemons, pumpkins, onions, garlic, and other herbs. On November 20, the chronometers were put back on board.
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The ship was one of the first to test the lightning conductor invented by William Snow Harris. FitzRoy obtained five examples of the Sympiesometer, a kind of mercury-free barometer patented by Alexander Adie and favoured by FitzRoy as giving the accurate readings required by the Admiralty. In addition to its officers and crew, Beagle carried several supernumeraries, passengers without an official position. FitzRoy employed a mathematical instrument maker to maintain his 22 marine chronometers kept in his cabin, as well as engaging the artist/draughtsman Augustus Earle to go in a private capacity.
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After storms, Beagle reached Montevideo on 26 July 1832, and took observations for the chronometers. An attempt to call at Buenos Aires for information was thwarted by officials, then FitzRoy agreed a request for ship's crew (and Darwin) to briefly occupy a Montevideo fort to dispel a revolution. On 22 August, after taking soundings in Samborombón Bay, Beagle began survey work down the coast from Cape San Antonio, Buenos Aires Province, Argentina. A caricature of the scene on the quarter deck while anchored at Bahia Blanca, painted around 24 September 1832.
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King Mongkut of Siam, Bangkok (European Dress), 1865–1866 In April 1862, Thomson left Edinburgh for Singapore, beginning a ten-year period spent travelling around the Far East. Initially, he established a joint business with William to manufacture marine chronometers and optical and nautical instruments. He also established a photographic studio in Singapore, taking portraits of European merchants, and he developed an interest in local peoples and places. He travelled extensively throughout the mainland territories of Malaya and the island of Sumatra, exploring the villages and photographing the native peoples and their activities.
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In total, Harrison received £23,065 for his work on chronometers. He received £4,315 in increments from the Board of Longitude for his work, £10,000 as an interim payment for H4 in 1765 and £8,750 from Parliament in 1773. This gave him a reasonable income for most of his life (equivalent to roughly £450,000 per year in 2007, though all his costs, such as materials and subcontracting work to other horologists, had to come out of this). He became the equivalent of a multi-millionaire (in today's terms) in the final decade of his life.
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An incredibly extensive array of precise instrumentation had to be readily available for Humboldt's terrestrial physicist. The expansive amount of scientific resources that characterized the Humboldtian scientist is best described in the book Science in Culture, > Thus the complete Humboldtian traveller, in order to make satisfactory > observations, should be able to cope with everything from the revolution of > the satellites of Jupiter to the carelessness of clumsy donkeys.Cannon, > Science in Culture, p. 76 Just some of such instruments included chronometers, telescopes, sextants, microscopes, magnetic compasses, thermometers, hygrometers, barometers, electrometers, and eudiometers.
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They specifically worked out a plan with ISS Reshetnev on the provisioning of high-quality electronic components in compliance with the state-run import substitution programs. These spacecraft differ from their predecessors in that they possess enhanced navigation functions. They will have a new design and amenities, and more accurate chronometers. GLONASS K2 will emit new signals code division that will provide greater accuracy in determining the coordinates of the users, and more accurate binding in those systems, such as computer systems, where accurate time references are important.
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Hall had complained about Budington's drunken behavior, and it fully came to light from the crew's testimony at the inquest following the expedition. With Tyson watching over the ship, Hall took two sleds with first mate Chester and the native guides Ipirvik and Hendrik, leaving on October 10\. The Funeral of Captain Charles Francis Hall The day after leaving, Hall sent Hendrik back to the ship to retrieve a number of forgotten items. Hall also sent back a note to Bessels, reminding him to wind the chronometers at the right time every day.
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Alternatively, the width of small transverse bands in the spine may be used to infer daily information about cloud cover or plant productivity, although this remains to be tested. It has also been shown that regular waxy banding on the sides of a Costa Rican cactus (Lemaireocereus aragonii) indicate annual growth and can be used as temporal chronometers. Transverse banding on a spine from a fishhook barrel cactus growing in Tucson, Arizona. Each band (1 couplet of thick white and thin red lines) represents one day of spine growth.
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Not many, about ten of these, survive and none in their original form, as Arnold was constantly upgrading their specification. They appear to have originally had a pivoted detent escapement, with a steel balance and a helical balance spring. A spiral bimetallic curb acting on this spring was intended to provide the temperature compensation, but this system evidently did not work, as every watch was subsequently altered and improved by Arnold shortly afterwards. Surviving chronometers from this series include Numbers 3, 29 Page 31-33 Randall & Good - Catalogue of Precision Watches in the British Museum.
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The rise of railroading during the last half of the 19th century led to the widespread use of pocket watches. A famous train wreck on the Lake Shore and Michigan Southern Railway in Kipton, Ohio on April 19, 1891 occurred because one of the engineers' watches had stopped for four minutes. The railroad officials commissioned Webb C. Ball as their Chief Time Inspector, in order to establish precision standards and a reliable timepiece inspection system for Railroad chronometers. This led to the adoption in 1893 of stringent standards for pocket watches used in railroading.
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The collection includes one of the early marine chronometers by Ferdinand Berthoud, a pendule sympathique by Breguet, a pocket watch with astronomical indications by Auch, several bespoke late 20th century watches by George Daniels, one of the few reproductions of the astrarium by De Dondi to name just a few highlights. Furthermore, there are superb Geneva made enameled pocket watches, and a most instructive timeline illustrating the history of the Neuchâtel pendule. Additionally there is a good small display of locally made clocks and watches including such Zurich makers as Bachoffner, Liechti and Ochsner.
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General Wolfe Statue (Greenwich Guide) accessed 10 December 2007 Nearby a major group of buildings within the park includes the former Royal Observatory, Greenwich; the Prime Meridian passes through this building. Greenwich Mean Time was at one time based on the time observations made at the Royal Greenwich Observatory, before being superseded by Coordinated Universal Time. While there is no longer a working astronomical observatory at Greenwich, a ball still drops daily to mark the exact moment of 1 p.m., and there is a museum of astronomical and navigational tools, particularly John Harrison's marine chronometers.
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During the Industrial Revolution, daily life was organized around the home pendulum clock. More accurate pendulum clocks, called regulators, were installed in places of business and railroad stations and used to schedule work and set other clocks. The need for extremely accurate timekeeping in celestial navigation to determine longitude drove the development of the most accurate pendulum clocks, called astronomical regulators. These precision instruments, installed in naval observatories and kept accurate within a second by observation of star transits overhead, were used to set marine chronometers on naval and commercial vessels.
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Cutler worked at Hewlett-Packard Laboratories (1957–1999), where he developed oscillators, atomic frequency standards and designed atomic chronometers. In 1999, he went on to work at Agilent Technologies, a spin-off from H-P, where he developed quartz oscillators, atomic clocks, and used the Global Positioning System to synchronize clocks worldwide. Towards the end of his time there, he concentrated on designs related to the chip scale atomic clock. In 1964, Leonard Cutler and his colleague Al Bagley invented the first all-solid-state cesium-beam chronometer known as the HP5060A Cesium Beam Clock.
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When D'Entrecasteaux was tasked to investigate the fate of Lapérouse's expedition and given command of the Recherche, Willaumez, promoted to Ensign in 1791, followed him, and was tasked with navigation and chronometers. During the campaign, D'Entrecasteaux promoted him to Lieutenant, and appointed Knight of the Order of Saint Louis. In the course of the exploration, he also named the Willaumez Peninsula after him. D'Entrecasteaux died of scurvy on 21 July 1793 and his ships sailed to Java, where they were interned by the Dutch, who were then at war with France.
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A third public house, the Red Lion, situated on the lower High Street, reverted to a residence in the early 20th century. John Harrison Church of England Primary School is situated on North Street. Built in the last decade of the 19th century and formerly named Barrow upon Humber Church of England Primary School, it was renamed in honour of John Harrison, designer of maritime chronometers, who lived in the village until 1736. The village is the home of Barton-upon-Humber Rugby Union Football Club, whose clubhouse is on Mill Lane.
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The 24-hour analog dial was reserved for more specialized applications, such as astronomical clocks and chronometers. Most analog clocks and watches today use the 12-hour dial, on which the shorter hour hand rotates once every 12 hours and twice in one day. Some analog clock dials have an inner ring of numbers along with the standard 1-to-12 numbered ring. The number 12 is paired either with a 00 or a 24, while the numbers 1 through 11 are paired with the numbers 13 through 23, respectively.
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Horology ("the study of time", related to Latin horologium from Greek , "instrument for telling the hour", from hṓra "hour; time" and -o- interfix and suffix -logy), . is the study of the measurement of time. Clocks, watches, clockwork, sundials, hourglasses, clepsydras, timers, time recorders, marine chronometers, and atomic clocks are all examples of instruments used to measure time. In current usage, horology refers mainly to the study of mechanical time-keeping devices, while chronometry more broadly includes electronic devices that have largely supplanted mechanical clocks for the best accuracy and precision in time-keeping.
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This business was established in 1899 by Coventry-born Alfred James White (1870-) and Norwegian Peter August Poppe (1870-1933). They had met in Austria at a weapons factory where Poppe was on secondment from his job in Norway with Kongsberg weapons factory. White was the son of a retired watchmaker, supplier of chronometers to The Admiralty and director of White and Poppe customers Swift and Singer. White's family provided most of the capital for this new business and initially White looked after the accounts and called himself general manager.
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Kofe, Laumua; Palagi and Pastors in Tuvalu: A History, Ch. 15 Mourelle's map and journal named the island El Gran Cocal ('The Great Coconut Plantation'); however, the latitude and longitude was uncertain. Longitude could be reckoned only crudely at the time, as accurate chronometers did not become available until the late 18th century. The next European to visit was American Arent Schuyler de Peyster, of New York, captain of the armed brigantine or privateer Rebecca, sailing under British colours.The De Peysters. corbett-family-history.com He passed through the southern Tuvaluan waters in May 1819.
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Due to delays in proceeding with the border project, the British Admiralty asked him in the meantime to determine the longitude of various European locations, such as Madeira, with the help of chronometers, for which the SS Comet had been specially outfitted. He was joined from 30 June to 17 August 1824 by Humphry Davy who used the voyage to Norway to test his zinc protectors for ships' bottoms.The Royal Society, MC. 1. 114 In 1825 Tiarks was elected a Fellow of the Royal Society as "a person well versed in mathematics and nautical astronomy".
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However, he was not awarded the prize by the Board and was forced to fight for his reward, finally receiving payment in 1773, after the intervention of parliament. The French were also very interested in the problem of Longitude, and the Academy examined proposals and also offered prize money, particularly after 1748. Initially the assessors were dominated by the astronomer Pierre Bouguer who was opposed to the idea of chronometers, but after his death in 1758 both astronomical and mechanical approaches were considered. Two clock-makers dominated, Ferdinand Berthoud and Pierre Le Roy.
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While competitive chronometer testing took place at the observatories in Neuchâtel (1866–1975) and Geneva (1873–1967), testing of large numbers of watches intended for public sale was conducted by the independent Bureaux officiels de contrôle de la marche des montres (B.O.s) established between 1877 and 1956. Between 1961 and 1973,F. von Osterhausen, Wristwatch Chronometers: Mechanical Precision Watches and Their Testing (Schiffer; 2ed., Atglen, 1997) “a chronometer [was] a precision watch, which [was] regulated in several positions and at different temperatures and which had received a certificate [from the (“B.O.)].
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In 1899 the R.F. Matthews was the first ship to use wireless communication to request assistance at sea. Using radio for determining direction was investigated by "Sir Oliver Lodge, of England; Andre Blondel, of France; De Forest, Pickard; and Stone, of the United States; and Bellini and Tosi, of Italy." The Stone Radio & Telegraph Company installed an early prototype radio direction finder on the naval collier Lebanon in 1906. By 1904 time signals were being sent to ships to allow navigators to check their chronometers. The U.S. Navy Hydrographic Office was sending navigational warnings to ships at sea by 1907.
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There are, however, various instances where the correlation is not as clear. This strategy may not apply when the parent- daughter pair achieve secular equilibrium very rapidly or when the half-life of the daughter nuclide is significantly shorter than the time that has elapsed since purification of the nuclear material, e.g. 237Np/233Pa. Another possible complication is if in environmental samples, non-equivalent metal/ion transport for parents and daughter species may complicate or invalidate the use of chronometric measurements. Special age-dating relationships exist, including the commonly employed 234U/230Th and 241Pu/241Am chronometers.
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It was decided to go beyond the budget boundaries, so the crews also bought two chronometers by inventor Arnold John (№ 518 and 2110), and two – by (№ 920 and 922), three- and four-foot refractors with achromatic lenses, a 12-inch reflecting telescope, and for Simonov – a transit instrument and an attitude indicator. Repeating circles by Edward Troughton proved to be inconvenient for use at sea. For ‘Vostok’ they bought sextants by Troughton and Peter Dollond; officers bought some of the instruments with their own money. Thermometers were designed with the Réaumur scale used in Russia, but Simonov also used the Fahrenheit temperature scale.
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Then Beagle was to proceed to Point Venus, Tahiti, and on to Port Jackson, Australia, which were known points to verify the chronometers. No time was to be wasted on elaborate drawings; charts and plans should have notes and simple views of the land as seen from the sea showing measured heights of hills. Continued records of tides and meteorological conditions were also required. An additional suggestion was for a geological survey of a circular coral atoll in the Pacific Ocean including its profile and of tidal flows, to investigate the formation of such coral reefs.
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Both these interests possibly hearkened back to his years at sea. In 1862 Carkeek suggested that a transit observatory and time ball – the first in New Zealand – be added to the new Customs House due to be built on reclaimed land on the Wellington waterfront; a time service was important for captains of visiting ships needing to correct their chronometers. In December 1863 an astronomical clock arrived from Britain, and it was connected electrically to the time ball so that the ball dropped at noon each day (but never on Sundays). The time ball began operation on 8 March 1864.
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An improved sailing ship, the (nau or carrack), enabled the Age of Exploration with the European colonization of the Americas, epitomized by Francis Bacon's New Atlantis. Pioneers like Vasco da Gama, Cabral, Magellan and Christopher Columbus explored the world in search of new trade routes for their goods and contacts with Africa, India and China to shorten the journey compared with traditional routes overland. They produced new maps and charts which enabled following mariners to explore further with greater confidence. Navigation was generally difficult, however, owing to the problem of longitude and the absence of accurate chronometers.
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F.P. Journe is a Swiss high-end watch manufacture founded in 1999 and named after the founder, François-Paul Journe. The only three-time winner of the Aiguille d'Or grand prize from the , F.P. Journe focuses on complex precision chronometers with a production of around 800 watches per year. 20% of the company was acquired by Chanel in 2018 for an undisclosed amount. F.P. Journe is the only watchmaker still based in central Geneva, with company headquarters, manufacturing facilities, and an exhibition space with library housed in a converted gaslamp factory in the Coulouvreniere Rois neighborhood.
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As captain of Shearwater he carried out extensive surveying the Sea of Marmora and the Bosphorus, as well as in the Mediterranean and Indian Ocean. In the Bosphorus he designed ingenious methods to measure the flow at different levels, showing currents and counter-currents. In 1874, Wharton was involved in preparations for the observations of the first transit of Venus, involving the transport of numerous chronometers to determine the longitude of observation stations in the Indian Ocean. He collaborated with David Gill on this work, who became a lifelong friend, and would later be Astronomer at the Cape of Good Hope.
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122 The first effective design of detent escapement was invented by John Arnold around 1775, but with the detent pivoted. This escapement was modified by Thomas Earnshaw in 1780 and patented by Wright (for whom he worked) in 1783; however, as depicted in the patent it was unworkable. Arnold also designed a spring detent escapement but, with improved design, Earnshaw's version eventually prevailed as the basic idea underwent several minor modifications during the last decade of the 18th century. The final form appeared around 1800, and this design was used until mechanical chronometers became obsolete in the 1970s.
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When Hurd died on 29 April 1823, he was a superintendent of chronometers and a commissioner for the discovery of longitude. Hurd was survived by his wife and he left plantations in both America and the West Indies.Andrew C. F. David, ‘Hurd, Thomas Hannaford (bap. 1747, d. 1823)’, Oxford Dictionary of National Biography, Oxford University Press, September 2004; online edn, January 2008 accessed 22 January 2010 To his wife he left "enslaved people on Grenada and Dominica that had been given and bequeathed to him by his 'worthy and respected friend' Samuel Proudfoot of Clapham Common".
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Determining longitude on land was fairly easy compared to the task at sea. A stable surface to work from, known coordinates to refer to, a sheltered environment for the unstable chronometers of the day, and the ability to repeat determinations over time made for great accuracy. For calculating longitude at sea however, early ocean navigators had to rely on dead reckoning, or if in sight of land, coastal navigation, which involves triangulating several bearings of the same land feature from different positions. Once out of sight of land, longitude became impossible to calculate, which sometimes led to tragedies in stormy or foggy conditions.
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In 1814, when Dent was just 24 years old, he was becoming well known as a watchmaker and clockmaker of some distinction: in this year he supplied a Standard Astronomical Clock for the Admiralty, and at least one pocket chronometer for the Colonial Office African Expedition. As early as 1814, Dent was making clocks and chronometers on his own account, but not in sufficient quantities to earn him a satisfactory livelihood. During 1815–29, it is believed that Dent worked for a number of well known firms. One such firm was Callum Brothers of Castle Street, Long Acre.
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All of these Greenwich meridians were located via an astronomic observation from the surface of the Earth, oriented via a plumb line along the direction of gravity at the surface. This astronomic Greenwich meridian was disseminated around the world, first via the lunar distance method, then by chronometers carried on ships, then via telegraph lines carried by submarine communications cables, then via radio time signals. One remote longitude ultimately based on the Greenwich meridian using these methods was that of the North American Datum 1927 or NAD27, an ellipsoid whose surface best matches mean sea level under the United States.
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It seems likely that before 1775, Arnold's earliest pocket chronometers, such as those supplied to Phipps and Banks, were plain watches with centre seconds motion, largely resembling Maskelyne's cylinder watch by Ellicott. Certainly, those few surviving examples are of this caliper such as No. 3.British Museum Cat. No.4 By 1772, Arnold had finalized the design of his pocket timekeepers and started series production with a standardized movement caliper, this being around 50 mm in diameter, larger than a conventional watch of the period, and showing seconds with a pivoted detent escapement and spiral compensation curb.
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The bimetallic compensation balance and the spring detent escapement in the forms designed by Earnshaw have been used essentially universally in marine chronometers since then. For this reason, Earnshaw is also generally regarded as one of the pioneers of chronometer development. However, because Arnold's balance spring patents were in force (each for 14 years), Earnshaw could not use the helical balance spring until the 1775 patent lapsed in 1789, and, in the case of the 1782 patent, 1796. Until around 1796, Earnshaw made watches with flat balance springs only,Catalogue of precision watches in the British Museum. 1990 Cat. No. 58 P.80.
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Hans Momsen's organ was only played during a single year in the Fahretoft church but a sundial made by him can still be seen today at the entrance to the church house. Numerous of his astronomical tools are preserved and are on display in museums in the area. His skills are cited in Theodor Storm's novella Der Schimmelreiter where Hans Mommsen, a builder of "chronometers, telescopes and organs" is cited. While Hans Mommsen is only a supporting character in the novella the real Momsen is said to have been Storm's inspiration for the protagonist Hauke Haien.
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Arniston sailed from Port de Galle on 4 April 1815 in a convoy of six other East Indiamen, under the escort of HMS Africaine and .Grocott 1997, primary sources Among her 378 passengers were many invalid soldiers and sailors, plus 14 women and 25 children. During the passage from Ceylon, at one o'clock every day, the ships signalled each other their longitude that they calculated using their chronometers. In this way, the ships were able to compare their respective instruments, and the master of the Arniston was able to learn his longitude too, as long as he remained in the convoy.
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On September 21, 1874 Stanley arrived in Zanzibar. He took with him three young Englishmen, Frederick Barker and the brothers Francis and Edward Pocock, and Kalulu, an African he had taken to England on his earlier trip and who was educated briefly in England. He also took 60 pounds of cloth, copper wire and beads (Sami Sami) for trading, a barometer, watches and chronometers, sextant, compasses, photographic equipment, Snider rifles and elephant gun(s), and the parts of a boat with single sail built by James Messenger. He named it the Lady Alice after his fiancee.
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Elias Howe Jr. was born on July 9, 1819, to Dr. Elias Howe Sr. and Polly (Bemis) Howe in Spencer, Massachusetts. Howe spent his childhood and early adult years in Massachusetts, where he apprenticed in a textile factory in Lowell beginning in 1835. After mill closings due to the Panic of 1837, he moved to Cambridge, Massachusetts, to work as a mechanic with carding machinery, apprenticing along with his cousin Nathaniel P. Banks. Beginning in 1838, he apprenticed in the shop of Ari Davis, a master mechanic in Cambridge who specialized in the manufacture and repair of chronometers and other precision instruments.
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However, no mechanical movement could ultimately compare to the accuracy of the quartz movements being developed. Accordingly, such chronometer certification ceased in the late 1960s and early 1970s with the advent of the quartz watch movement. In 2017 the Observatory Chronometer Database (OCD) Observatory Chronometer Database (OCD) went online, which contains all mechanical timepieces ("chronometres-mecaniques") certified as observatory chronometers by the observatory in Neuchatel from 1945 to 1967, due to a successful participation in the competition which resulted in the issuance of a "Bulletin de Marche". All database entries are submissions to the wristwatch category ("chronometres-bracelet") at the observatory competition.
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Model number 116509 white gold silver dial Rolex Daytona. The third series, introduced in 2000, has a movement made by Rolex (designated Calibre 4130) and a six-digit model number, Reference 116520. Externally, the third series may be distinguished by close examination of the dial; the two sub-dials at the 3 and 9 o'clock positions are now slightly above an imaginary line drawn between the 3 and 9 o'clock chapters, and the running seconds sub-dial has been relocated from the 9 o'clock position to the 6 o'clock position. The six-digit Daytonas are certified, self-winding chronometers with chronograph functions.
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While this scheme worked well enough to allow Harrison to meet the standards set by the Longitude Act, it was not widely adopted. Around 1765, Pierre Le Roy (son of Julien Le Roy) invented the compensation balance, which became the standard approach for temperature compensation in watches and chronometers. In this approach, the shape of the balance is altered, or adjusting weights are moved on the spokes or rim of the balance, by a temperature-sensitive mechanism. This changes the moment of inertia of the balance wheel, and the change is adjusted such that it compensates for the change in modulus of elasticity of the balance spring.
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The time ball is the red ball on a post – when it drops a certain time is signalled. This allowed clocks to be set from afar with great accuracy, particularly the chronometers of ships on the River Thames below, prior to sailing. The observatory would first determine the time by stellar observations. The red time ball of Greenwich was established in 1833, and is noted as a public time signal. The time ball in modern times is normally in a lowered position, then starting at 12:55pm, the ball begins to rise, then at 12:58 it reaches the top; at 1pm the ball drops.
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Forewarned by Saltus's experience, Chaney travels further into the future. Not having chosen a date, and disillusioned by his experiences on the 1980 trip, he arrives at an indeterminate point in "2000-plus", by which time the power from the base's nuclear reactor has been disrupted, causing the chronometers set up for the travelers to shut down. Venturing outside the building, he finds the base to be long-neglected, apart from a cistern and a grave. While further investigating the grave (which is that of Saltus), he is approached by a young man and a woman who identify themselves as Arthur and Kathryn's children.
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The company built the Elgin National Watch Company Observatory in 1910 to maintain scientifically precise times in their watches. The company produced many of the self-winding wristwatch movements made in the United States beginning with the 607 and 618 calibers (which were bumper wind) and the calibers 760 and 761 (30 and 27 jewels respectively). During World War II all civilian manufacturing was halted and the company moved into the defense industry, manufacturing military watches, chronometers, fuzes for artillery shells, altimeters and other aircraft instruments and sapphire bearings used for aiming cannons. Over time a number of additional plants were operated, mostly in Elgin.
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These were not as accurate as the boxed marine chronometer but were adequate for many. While the Lunar Distances method would complement and rival the marine chronometer initially, the chronometer would overtake it in the 19th century. The more accurate Harrison timekeeping device led to the much-needed precise calculation of longitude, making the device a fundamental key to the modern age. Following Harrison, the marine timekeeper was reinvented yet again by John Arnold who while basing his design on Harrison's most important principles, at the same time simplified it enough for him to produce equally accurate but far less costly marine chronometers in quantity from around 1783.
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Beagle. In December 1831 a British expedition departed under captain Robert FitzRoy, on board HMS Beagle, with the main purpose of making a hydrographic survey of the coasts of South America using calibrated chronometers and astronomical observations, producing charts for naval war or commerce. The longitude of Rio de Janeiro was to be found and also a geological survey made of a circular coral atoll in the Pacific ocean. FitzRoy thought of the advantages of having an expert in geology on board, and sought a gentleman naturalist who could be his companion. The young graduate, Charles Darwin, had hoped to see the tropics before becoming a parson, and took this opportunity.
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He was in charge of the chronometers and made the astronomical observations needed to fix the ship's position. The steamer Vega left Karlskrona on 22 June 1878, picking up Nordenskiöld on 17 July at Tromsø. Vega crossed the Barents sea, and accompanied by three cargo vessels sailed along the northern coast of Russia, arriving at Dikson on 6 August 1878. Leaving two of the cargo ships to sail inland from that port to collect cargoes of grain, the Vega and Lena skirted the coast to the mouth of the Lena River, where the Lena left on 28 August 1878 to sail up the river to Yakutsk.
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Observatory Inlet was named by George Vancouver in 1793, because he set up his observatory on the shore of the inlet, at Salmon Cove, in order to calibrate his chronometers. His two vessels, HMS Discovery and HMS Chatham, stayed in Salmon Cove from July 23 to August 17, 1793. During this time a boat surveying expedition under Vancouver himself explored Behm Canal. Vancouver also named three headlands at the entrance of Observatory Inlet: Maskelyne Point, for Nevil Maskelyne, the Astronomer Royal, Wales Point, for William Wales, the mathematical master who sailed with James Cook, and Ramsden Point, after the famed mathematical instrument-maker Jesse Ramsden.
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Chondrites were formed by the accretion of particles of dust and grit present in the primitive Solar System which gave rise to asteroids over 4.54 billion years ago. These asteroid parent bodies of chondrites are (or were) small to medium-sized asteroids that were never part of any body large enough to undergo melting and planetary differentiation. Dating using 206Pb/204Pb gives an estimated age of 4,566.6 ± 1.0 Ma, matching ages for other chronometers. Another indication of their age is the fact that the abundance of non-volatile elements in chondrites is similar to that found in the atmosphere of the Sun and other stars in our galaxy.
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18th-century azimuthal compass held in the National Archaeological Museum of Spain An azimuth compass (or azimuthal compass) is a nautical instrument used to measure the magnetic azimuth, the angle of the arc on the horizon between the direction of the sun or some other celestial object and the magnetic north. This can be compared to the true azimuth obtained by astronomical observation to determine the magnetic declination, the amount by which the reading of a ship's compass must be adjusted to obtain an accurate reading. Azimuth compasses were important in the period before development of the reliable chronometers needed to determine a vessel's exact position from astronomical observations.
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A map showing lines of equal magnetic declination in January 2015 Early navigators in the northern hemisphere could calculate latitude relatively easily when the night sky was clear by observing the elevation of Polaris, a star that is very close to the north celestial pole. However, calculating longitude was impossible until chronometers that could keep time accurately throughout a long voyage were developed. In 1688 King Philip III of Spain (1578–1621) offered a large reward to anyone who could find a practical solution to determining longitude. A novel approach, apparently originating with the Jesuit missionary Christoforo Borri, was to create charts that mapped points of equal magnetic declination.
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Weddell's ships, Jane and Beaufoy, under full sail In 1822 Weddell, again in command of Jane and this time accompanied by a smaller ship, the cutter Beaufoy, set sail for the south with instructions from his employers that, should the sealing prove barren, he was to "investigate beyond the track of former navigators". This suited Weddell's exploring instincts, and he equipped his vessel with chronometers, thermometers, compasses, barometers and charts. In January 1823 he probed the waters between the South Sandwich Islands and the South Orkney Islands, looking for new land. Finding none, he turned southward down the 40°W meridian, deep into the sea that now bears his name.
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Pitt interested himself in the porcelain manufactory of Plymouth porcelain, where they used the white saponaceous china stone found on his land in Cornwall. Angelica Kauffman wrote to him on the free importation into England by artists of their own studies and designs. Pitt was a friend of Mary Delany, to whom he gave for her lifetime portraits of Sir Bevil Grenville, his wife, and his father, and he proposed to John Maurice, Count of Brühl that they should jointly assist Thomas Mudge in his plans for the improvement of nautical chronometers. The wainscoting of the stalls in Carlisle Cathedral, where his uncle Charles Lyttelton was bishop, was designed by him.
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There was only one full-time watchmaker named Leopold Berthoud who occupied himself by creating Ulysse Nardin's marine chronometers and deck watches for collectors looking to own an anachronistic but sublimely made piece of naval history. Another person that Schnyder found at the manufacture was Jean-Jacques Haldimann. “It was essentially with these one-and-a-half employees (as Haldimann was not actually on company payroll at that time) that I started at Ulysse Nardin. I realized that if I were to undertake this resurrection, I would have to breathe life back into this carcass based on the strength of our products,” says Schnyder.
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At the time, Bonaparte was interested in serving in the navy rather than army because of his proficiency in mathematics and artillery, both valued skills on warships. Copying the work methods of Cook's scientists, the scientists on this voyage would base their calculations of longitude on precision chronometers and the distance between the moon and the sun followed by theodolite triangulations or bearings taken from the ship,De Langle's means of taking bearings was exactly that used by Cook. the same as those taken by Cook to produce his maps of the Pacific islands. As regards geography, Lapérouse decisively showed the rigour and safety of the methods proven by Cook.
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The rockets were simultaneously observed from Armagh Observatory and Dunsink Observatory in County Dublin, and the data used to calculate latitude and longitude. The same technique was used again in August 1841 to determine Markee's location. Rockets were fired from Culkagh Mountain, about 6 miles north-east of Lough Allen, and the precise moment of their extinction was observed at both Markree and Armagh. The results varied by only 0.03 seconds from the average of 15 chronometers lent by Dent of London. Similar principles were applied on 10–12 August 1847, to calculate the difference of longitude between Markree and Killiney, ninety-eight miles away in County Dublin.
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Early watches were terribly imprecise; a good one could vary as much as 15 minutes in a day. Modern precision (a few seconds per day) was not attained by any watch until 1760, when John Harrison created his marine chronometers. Precision was attained as from 1854 first by the Waltham Watch Company, through the industrialisation of the manufacturing process of the movement part, in order to attain the necessary precision: they won a gold medal at the 1876 Philadelphia Centennial Exposition with a lot of watches taken at random out of the production line, showing the way to their peers in U.S.A. (e.g. Elgin Watch Company) and the worldwide watch industry.
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429 He also differed from Harrison regarding his temperature compensation method, which used the variation of the rotation radius of the balance by modifying the diameter of the balance through bi-metallic components, a method which would become a standard in chronometers. His technique for temperature compensation was highly efficient in that it worked without changing the length of the spiral balance spring, which he had discovered to be isochronous only at a precise given length (i.e. when frequency is independent of amplitude, so that a mechanical clock or watch runs at the same rate regardless of changes in its drive force, so it keeps correct time as the mainspring unwinds).
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Additional sheathing added to the hull added about seven tons to her burthen and perhaps fifteen to her displacement. The ship was one of the first to be fitted with the lightning conductor invented by William Snow Harris. FitzRoy spared no expense in her fitting out, which included 22 chronometers, and five examples of the Sympiesometer, a kind of mercury-free barometer patented by Alexander Adie which was favoured by FitzRoy as giving the accurate readings required by the Admiralty. To reduce magnetic interference with the navigational instruments, FitzRoy proposed replacing the iron guns with brass guns, but the Admiralty turned this request down.
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The need for an accurate clock for celestial navigation during sea voyages drove many advances in balance technology in 18th century Britain and France. Even a 1-second per day error in a marine chronometer could result in a 17-mile error in ship's position after a 2-month voyage. John Harrison was first to apply temperature compensation to a balance wheel in 1753, using a bimetallic ‘compensation curb’ on the spring, in the first successful marine chronometers, H4 and H5. These achieved an accuracy of a fraction of a second per day, but the compensation curb was not further used because of its complexity.
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View from Signal Hill Tower Signal Hill Tower Staircase The purpose of the tower was to house a time ball apparatus of the Hong Kong Observatory previously located in the nearby Marine Police Headquarters Compound.History of Hong Kong Time Service The apparatus operated in the building from January 1908 to June 1933, dropping once daily from 1908 to 1920, and twice a day from 1920 to 1933. The dropping of the time ball ceased on 30 June 1933 as the building itself was in disrepair, short of staff, and the method used to check the marine chronometers had become obsolete, in comparison with radio- telegraphy and telephony. The Urban Council restored the tower in the 1970s.
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A balance spring, or hairspring, is a spring attached to the balance wheel in mechanical timepieces. It causes the balance wheel to oscillate with a resonant frequency when the timepiece is running, which controls the speed at which the wheels of the timepiece turn, thus the rate of movement of the hands. A regulator lever is often fitted, which can be used to alter the free length of the spring and thereby adjust the rate of the timepiece. The balance spring is a fine spiral or helical torsion spring used in mechanical watches, alarm clocks, kitchen timers, marine chronometers, and other timekeeping mechanisms to control the rate of oscillation of the balance wheel.
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The inquest determined that, unable to see the Cape Otway lighthouse; having faulty chronometers on board; and not having been able to take a reading to establish his exact position due to bad weather conditions over the previous few days, the captain was unaware how close he was running to the coast. The fog lifted around 4am, revealing breakers and cliff faces. Captain Gibb quickly ordered sail to be set to come about and get clear of the coast, but they were unable to do so in time, and ran aground on a reef. The masts and rigging came crashing down, killing some people on deck and preventing the lifeboats from being launched effectively.
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To resolve this, the Admiralty instructed Captain Robert FitzRoy to command on a survey expedition. One of its essential tasks was a stop at Fernando Noronha to confirm its exact longitude, using the 22 chronometers on board the ship to give the precise time of observations. They arrived at the island in the late evening of 19 February 1832, anchoring at midnight. On 20 February FizRoy landed a small party to take the observations, despite difficulties caused by heavy surf, then sailed on for Bahia, Brazil that evening.FitzRoy, R. (1839) Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle between the years 1826 and 1836, London: Henry Colburn, pp. 58–60.
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After a two-year apprenticeship to a jeweler, Ball settled in Cleveland, Ohio to join a jewelry store. In 1891 there was a collision between Lake Shore and Michigan Southern Railway trains at Kipton, Ohio, which occurred because an engineer's watch had stopped. The railroad officials commissioned Webb C. Ball as their Chief Time Inspector, in order to establish precision standards and a reliable timepiece inspection system for railroad chronometers. He established strict guidelines for the manufacturing of sturdy, reliable precision timepieces, including resistance to magnetism, reliability of time keeping in 5 positions, isochronism, power reserve and dial arrangement, accompanied with record keeping of the reliability of the watch on each regular inspection.
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Reid & Sons exhibited at the Great Exhibition of 1851 In 1838 the company received a Royal Appointment from Queen Victoria. On the retirement of Christian Bruce Reid from the company in 1845 his two older brothers took Christian John Reid (1816-1891), son of David Reid Snr, as a partner in the company. The firm, known as Reid & Sons, operated from 12 Dean Street, 14 Grey Street (1843) and 41 Grey Street in Newcastle (1855) and exhibited at the Great Exhibition of 1851 and at the 1862 International Exhibition, again held in London. Between 1844 and 1898/9 Reid & Sons sent a number of marine chronometers for trial at Greenwich, coming second in 1844.
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In the early 1990s The Muffins got back together briefly to play at a private party, and a recorded extract from their performance appeared on a 1995 Cuneiform Records compilation, Unsettled Scores. In 1998, realising that there was still a demand for their music, Newhouse, Swann, Scott and Sears decided to officially reform The Muffins. Cuneiform Records had already re-issued all their old albums on CDs, and released a collection of unreleased tracks on Open City, and their early studio and home demos on Chronometers. The band assembled at Sears's house and jammed and recorded a track for a new Cuneiform Records sampler, Unsettled Scores, where Cuneiform artists performed each other's music.
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Ferdinand Berthoud's clocks soon became a success and were used on board ship for various test campaigns and charting voyages. In 1771, Borda boarded the frigate Flore, under Lieutenant Verdun de la Crenne, for a campaign of tests on sea chronometers, sailing from the Canary Islands to the Caribbean. Count Chastenet de Puységur (1752–1809), captain of the corvette Espiègle, accompanied Borda, captain of Boussole, in an expedition to the Canaries and the coast of Africa in 1774 and 1775.Collective work, Catherine Cardinal et al., Ferdinand Berthoud 1727–1807 Horloger mécanicien du Roi et de la Marine, La Chaux-de-Fonds: International Horology Museum, Institut L'homme et le temps, 1984, pages 33–37.
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Maury kept accurate time by the stars and planets. The time ball was dropped every day except Sunday precisely at the astronomically defined moment of Mean Solar Noon, enabling all ships and civilians within sight to know the exact time. By the end of the American Civil War, the Observatory's clocks were linked via telegraph to ring the alarm bells in all of the Washington, D.C. firehouses three times a day, and by the early 1870s the Observatory's daily noon-time signal was being distributed nationwide via the Western Union Telegraph Company. Time was also "sold" to the railroads and was used in conjunction with railroad chronometers to schedule American rail transport.
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The daily rate of the watch was therefore fixed as losing 24/9 seconds per day.Rees's Clocks Watches and Chronometers, 1819–20, David & Charles reprint 1970 When Deptford reached its destination, after correction for the initial error of 3 seconds and accumulated loss of 3 minutes 36.5 seconds at the daily rate over the 81 days and 5 hours of the voyage, the watch was found to be 5 seconds slow compared to the known longitude of Kingston, corresponding to an error in longitude of 1.25 minutes, or approximately one nautical mile. William Harrison returned aboard the 14-gun , reaching England on 26 March 1762 to report the successful outcome of the experiment.
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Cook's log is full of praise for the watch and the charts of the southern Pacific Ocean he made with its use were remarkably accurate. K2 was loaned to Lieutenant William Bligh, commander of HMS Bounty but it was retained by Fletcher Christian following the infamous mutiny. It was not recovered from Pitcairn Island until 1808 when it was given to Captain Folger, and then passed through several hands before reaching the National Maritime Museum in London. Initially, the cost of these chronometers was quite high (roughly 30% of a ship's cost). However, over time, the costs dropped to between £25 and £100 (half a year's to two years' salary for a skilled worker) in the early 19th century.
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Girard- Perregaux - Plain JaneGirard-Perregaux - Oh my... What a wonderful watch The observatory competitions ended with the advent of the quartz watch movement, in the late 1960s and early 1970s. In 2009, the Watch Museum of Le Locle has launched a new chronometry contest based on ISO 3159 certification. In 2017 the Observatory Chronometer Database (OCD) Observatory Chronometer Database (OCD) went online, which contains all mechanical timepieces ("chronometres- mecaniques") certified as observatory chronometers by the observatory in Neuchatel from 1945 to 1967, due to a successful participation in the competition which resulted in the issuance of a "Bulletin de Marche". All database entries are submissions to the wristwatch category ("chronometres- bracelet") at the observatory competition.
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For reasons which seem inadequate now, he confines himself to an explanation of "plain trigonometry" and one can only speculate that the true reason is that before Mr. Harrison did his famous work on sea-going chronometers, the navigator's need for spherical trig was relatively undeveloped. On the other hand Harris's evident delight in the new chart projection "commonly called Mercator's" is clearly and amusingly explained in the text. This is probably not a book for the general reader, and even for the historian of the 18th century it is specialist stuff. The navigator, however, is bound to read him with respect and admiration; he describes many enduring maritime truths in an engaging and entertaining style.
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From 1866 time signals were also sent to US Harvard University via the new transatlantic submarine cable. Airy's report to the Observatory's Board of Visitors in 1853 explained the function of the Shepherd master clock: > This clock keeps in motion a sympathetic galvanic clock in the Chronometer > room, which, therefore, is sensibly correct; and thus the chronometers are > compared with a clock which requires no numerical correction. The same > Normal Clock maintains in sympathetic movement the large clock at the > entrance-gate, two other clocks in the Observatory, and a clock at the > London Bridge Terminus of the South-Eastern Railway. It sends galvanic > signals every day along all the principal railways diverging from London.
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Chronometer of Jeremy Thacker c. 1714. Jeremy Thacker was an 18th-century writer and watchmaker (although see the important qualification under 'Hoax?' below), who for a long time was believed to be the first to have coined the word "chronometer" for precise clocks designed to find longitude at sea, though an earlier reference by William Derham has now been found.For example, Charles Aked, 'William Derham and the "Artificial Clockmaker"', Antiquarian Horology (September 1970 ), p. 504 – 'Although it is generally conceded that Jeremy Thacker first made use of the term "chronometer" in print in 1714, William Derham used it independently in his communication "Observations concerning the Motions of Chronometers" addressed to the Royal Society on 4 November 1714.
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In Chapter 9, Aubrey explains rather clearly, in dialogue with Maturin, how a chronometer or watch set to Greenwich time, compared with local noon, lets a navigator establish longitude, or distance from Greenwich as the reference time point, when the sole chronometer set to Greenwich time is broken by one of the crew. Because they left England in such a hurry, Aubrey was not able to fetch his own set of chronometers from home. After the standard issue ship chronometer is dropped and broken by the lieutenant while returning from the Baltic, the lack of a chronometer combined with constantly stormy skies made it impossible to accurately navigate, leading to the Ariels eventual foundering on the coast of France.
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A clock built by Cooke and Johnson was transferred from Brodrick's guildhall to the new building. A time ball, a mechanism which enables navigators aboard ships to verify the setting of their marine chronometers, was installed at the top of the clock tower when it was built. The guildhall time ball is believed to be the last to have been installed in the UK and also the highest to have been installed the UK. The building was damaged in bombing in May 1941 during the Hull Blitz of the Second World War. A 23-bell carillon was added to the bell tower, which is high, in 2004 and mechanised winding equipment for the clock was installed in 2013.
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I-8 left Brest on 5 October, with a cargo of German equipment, such as: machine guns, bomb sights, a Daimler-Benz torpedo boat engine, marine chronometers, radars, sonar equipment, anti-aircraft gunsights, electric torpedoes, and penicillin. The submarine also transported Rear Admiral Yokoi, naval attaché to Berlin since 1940; Captain Hosoya, naval attaché to France since December 1939; three German officers and four radar and hydrophone technicians. I-8 hit rough seas in the South Atlantic off the Cape of Good Hope, which delayed her arrival in Singapore. She radioed her position to Germany, but the message was intercepted by the Allies, prompting an attack by anti-submarine aircraft, which failed.
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He advised the Admiralty of his Plan for ascertaining the rates of chronometers by signal, which described his "time ball", a large hollow metal sphere rigged on a pole and attached to a mechanism so that it might be dropped at an exact time each day.David Aubin The Heavens on Earth: Observatories and Astronomy in Nineteenth-Century Science and Culture Duke University Press, 2010 In 1829 a test was made of his device at Portsmouth on the south coast of England, where the Royal Naval Academy was situated. In 1833 time balls were constructed at Greenwich, and in 1836 at Liverpool and Edinburgh. Wauchope submitted his scheme to American and French ambassadors when they visited England.
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Anthony Randall's double axis tourbillon as installed in a carriage clock Anthony Randall invented the double-axis tourbillon in January 1977 and subsequently patented it. The first working example was later constructed by Richard Good in 1978. In 1980 Anthony Randall made a double-axis tourbillon in a carriage clock, which was located in the (now closed) Time Museum in Rockford, Illinois, US, and was included in their Catalogue of Chronometers. In 2003, inspired by this invention, the young German watchmaker Thomas Prescher developed for the Thomas Prescher Haute Horlogerie the first flying double-axis tourbillon in a pocket watch and, in 2004, the first flying double-axis tourbillon with constant force in the carriage in a wristwatch.
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In 1914, Kew Observatory awarded a Rolex watch a Class A precision certificate, a distinction normally granted exclusively to marine chronometers. In November 1915, the company changed its name to Rolex Watch Co. Ltd. In 1919, Hans Wilsdorf moved the company from England to Geneva, Switzerland because of heavy post-war taxes levied on luxury imports and high export duties on the silver and gold used for the watch cases. In 1920 the company's name was officially changed to Montres Rolex S.A. and later to Rolex S.A. With administrative worries attended to, Wilsdorf turned the company's attention to a technical challenge: the infiltration of dust and moisture under the dial and crown, which damaged the movement.
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During the 1761 transit of Venus, Pingré went on one of the three observing campaigns organized by the Académie Royale, travelling to Rodrigues Island near Madagascar, which was unsuccessful."The Natural History and Human Drama of the 18th and 19th century Transit Expeditions to Mauritius and Rodrigues in the Indian Ocean", a talk by Anthony Cheke Pingré's subsequent discounting of Giovanni Battista Audiffredi's observations led to a scientific dispute.1761 transit of Venus dispute between Audiffredi and Pingré (PDF), Luisa Pigatto In 1767 he sailed to the Baltic with Charles Messier to test marine chronometers. Two years later he joined a successful expedition to Haiti to observe the Venus transit of 1769.
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Until the 1980s balance wheels were the timekeeping technology used in chronometers, bank vault time locks, time fuzes for munitions, alarm clocks, kitchen timers and stopwatches, but quartz technology has taken over these applications, and the main remaining use is in quality mechanical watches. Modern (2007) watch balance wheels are usually made of Glucydur, a low thermal expansion alloy of beryllium, copper and iron, with springs of a low thermal coefficient of elasticity alloy such as Nivarox. The two alloys are matched so their residual temperature responses cancel out, resulting in even lower temperature error. The wheels are smooth, to reduce air friction, and the pivots are supported on precision jewel bearings.
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Pascal, Roberval and Senator Carcavy were the judges, and neither of the two submissions (by John Wallis and Antoine de Lalouvère) were judged to be adequate. While the contest was ongoing, Christopher Wren sent Pascal a proposal for a proof of the rectification of the cycloid; Roberval claimed promptly that he had known of the proof for years. Wallis published Wren's proof (crediting Wren) in Wallis's Tractus Duo, giving Wren priority for the first published proof. Fifteen years later, Christiaan Huygens had deployed the cycloidal pendulum to improve chronometers and had discovered that a particle would traverse a segment of an inverted cycloidal arch in the same amount of time, regardless of its starting point.
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Prior to the introduction of standard time, each municipality throughout the clock-using world set its official clock, if it had one, according to the local position of the Sun (see solar time). This served adequately until the introduction of rail travel in Britain, which made it possible to travel fast enough over long distances to require continuous re-setting of timepieces as a train progressed in its daily run through several towns. Greenwich Mean Time, the mean solar time on the Prime Meridian at Greenwich, England, was established to solve this problem: all clocks in Britain were set to this time regardless of local solar noon. Chronometers or telegraphy were used to synchronize these clocks.
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Among the orders received was one from a nobleman in Scotland who commissioned 2,500 watches, having decided to present every man in his son's regiment with a repeater watch: in gold for officers, silver for other ranks. In 1914, Mathey-Tissot was represented at the Kew Observatory Competition by six Observatory Chronometers capable of split-second timing, all six being rated 'Class A' with the comment 'specially good'. The same year, Mathey-Tissot gained the Grand Prix at the Swiss National Exhibition. During the First World War, the company supplied the United States Army's Corps of Engineers with precision chronographs in large quantities, while General Pershing, commanding the United States Expeditionary Force, chose the watch to award to members of his own staff.
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Davis did not provide the latitude of these islands, indicating they were away from the Patagonian coast (they are actually away). Positional errors due to the longitude problem continued to be a problem till the late 19th century, when accurate chronometers were first produced, although Destefani asserts the error here to be "unusually large". In 1594, they may have been visited by English commander Richard Hawkins with his ship the Dainty, who, combining his own name with that of Queen Elizabeth I, the "Virgin Queen", gave a group of islands the name of "Hawkins' Maidenland". However, the latitude given was off by at least 3 degrees and the description of the shore (including the sighting of bonfires) casts doubts on his discovery.
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In celestial navigation, knowledge of the time at Greenwich (or another known place) and the measured positions of one or more celestial objects allows the navigator to calculate latitude and longitude. Reliable marine chronometers were unavailable until the late 18th century and not affordable until the 19th century. After the method was first published in 1763 by British astronomer royal Nevil Maskelyne, based on pioneering work by Tobias Mayer, for about a hundred years (until about 1850)Lecky, Squire, Wrinkles in Practical Navigation mariners lacking a chronometer used the method of lunar distances to determine Greenwich time as a key step in determining longitude. Conversely, a mariner with a chronometer could check its accuracy using a lunar determination of Greenwich time.
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In Hamburg, in 1867, he founded the private North German Naval Observatory (Norddeutsche Seewarte), which he directed until 1875 when it became the German Naval Observatory (Deutsche Seewarte), an agency of the German Empire. The purpose of the observatory was to promote and to facilitate maritime intercourse. It was composed of a department of maritime meteorology; a bureau of nautical, meteorological, and magnetic instruments; a department of coast meteorology and signal service; and a bureau for testing chronometers. In 1945, the tasks of the German Naval Observatory were turned over to the German Hydrographic Institute (Deutsche Hydrographische Institut), and in 1990 that agency in turn became part of the present day Federal Department of Shipping and Hydrography (Bundesamt für Seeschifffahrt und Hydrographie).
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This novel was aimed at younger readers, as well as adults, and takes the viewpoint of a new midshipman joining the Royal Navy on HMS Centurion in 1740 on this voyage. The boy is on the one ship that makes the entire voyage, and he is one of the survivors. Seen by the midshipman Peter Palafox, the sense of the adventure is depicted, as he sees the world and learns the discipline, hardships and rewards of the Royal Navy. The hardships of the voyage are not dismissed, with counts of the deaths from scurvy, whose cure was not yet understood, and the problems of navigation without the precise knowledge of location gained by chronometers to measure longitude, depicted in detail.
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In 2017, the company appointed Patrick Pruniaux, a previous executive of Apple, as its new CEO. In 2019, Ulysse Nardin has released three new calibers (UN-230, UN-371 and UN-631). The company still occupies its original headquarters in Le Locle, one of the main watch production hubs in northwest Switzerland and has also three manufacturing plants in: La Chaux-de-Fonds (R&D; and movement production site), Le Locle (Donzé Cadrans site, which belongs to Ulysse Nardin but also produces enamel dials for other companies) and Sion (Sigatec site, which produces micromecanics components in silicium). While marine wrist chronometers are still a specialty for the brand, it produces luxury complicated timepieces with high sophistication for men and women.
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In the nineteenth century, the introduction of standard time and time zones divorced the "time of day" from local mean solar time and any links to astronomy. Time signals, like the bells and dials of public clocks, once were relatively local affairs; the ball that is dropped in Times Square on New Year's Eve in New York City once served as a time signal whose original purpose was for navigators to check their marine chronometers. However, when the railroads began running trains on complex schedules, keeping a schedule that could be followed over distances of hundreds of miles required synchronization on a scale not attempted before. Telegraphy and later shortwave radio were used to broadcast time signals from the most accurate clocks available.
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Knowing the actual local time at each present location by astronomy, they could easily determine the ship's exact position and longitude on a chart. The results of their observations was published in 1773 under the title Voyage fait par ordre du roi, pour éprouver les horloges marines ("Voyage made by order of the king, to test marine chronometers"). We can also cite among his major works le Neptune du Nord or l'Atlas du Cattegat et de la Baltique, an atlas of the Kattegat and the Baltic Sea that took him 25 years. Made lieutenant de vaisseau on 1 October 1773, then deputy inspector of naval charts and plans, he also became deputy inspector of the naval academy on 15 May 1776.
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Time ball on the Nelson Monument On top of the tower is a time ball, a large ball which is raised and lowered to mark the time. It was installed in 1852 to act as a time signal to the ships in Edinburgh's port of Leith, and to ships at the anchorage in the Firth of Forth known as Leith Roads, allowing the ships to set their chronometers. The time ball was the idea of Charles Piazzi Smyth, the Astronomer Royal for Scotland, and was originally triggered by a clock in the adjacent City Observatory, to which it was connected by an underground wire. The mechanism was the work of Maudslay, Sons & Field of Lambeth, who had previously constructed the time ball mechanism for Greenwich Observatory.
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Vidal sailed aboard in December 1835, carrying 12 chronometers. He intended to calculate the meridian arc length to the Cape Verde Islands, and the west coast of Africa. He eventually carried out detailed surveys all along the African coast, so that by 1838 the Secretary of the Royal Geographical Society could remark of the survey that > This tedious undertaking is drawing to a close, and will then be of equal > utility to the fair traders and the anti-slavery cruisers. It is fortunately > in the hands of such a man as Captain Vidal, R.N., who has steadily devoted > himself during a long period of ill-health, to complete this unpopular work, > and to connect with it a minute examination of the Canary Islands.
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The Hughes family were originally clockmakers in the east end of London who progressed into supplying sextants and marine chronometers to ships coming into the River Thames. In 1712 Thomas Hughes became a member of the Worshipful Company of Clockmakers at the age of 26 and was elected as Master of the Worshipful Company of Clockmakers in 1742. His son, Thomas Hughes (junior) had his business at 25 New Bond Street London and was elected as Master of the Worshipful Company of Clockmakers in 1762. In 1781 William Hughes, believed to be the son of Thomas Hughes Junior, was elected freeman of the Worshipful Company of Clockmakers and sold a cabin clock to Captain Cook. Joseph Hughes, believed to be the son of William born in 1781, lived and worked at 16 Queen Street, Ratcliffe.
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He is conducting research about the isotopic compositions of refractory inclusions in meteorites to understand the earliest history of the Solar System. Short- lived chronometers such as the 26Al-26Mg system can resolve time differences of only a few tens of thousands of years for events that occurred 4.55 billion years ago. Isotopic fractionation effects and the relative abundances of trace elements are used to constrain thermal histories and redox conditions in the solar nebula and on the asteroidal parent bodies of meteorites. Tiny (<10 µm in diameter) grains of silicon carbide, graphite, and other refractory minerals and rocks condensed around dying stars (mostly red giant stars and supernovae) survived potentially destructive processes in the interstellar medium and during solar system formation, and can now be found in meteorites.
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Two chronometers were synchronized, and taken to the two telegraph offices to conduct the test and check that time was accurately transmitted. The method was soon in practical use for longitude determination, in particular by the U.S. Coast Survey, and over longer and longer distances as the telegraph network spread across North America. Many technical challenges were dealt with. Initially operators sent signals manually and listened for clicks on the line and compared them with clock ticks, estimating fractions of a second. Circuit breaking clocks and pen recorders were introduced in 1849 to automate these process, leading to great improvements in both accuracy and productivity. The Telegraphic Net of Longitude in the USA and eastern Canada, 1896. Data from Schott (1897). Dotted lines show the two transatlantic telegraph connections to Europe.
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Riddle's most valuable work was A Treatise on Navigation and Nautical Astronomy (1824; 4th edition 1842; 8th edition 1864), forming a complete course of mathematics for sailors, and combining practice and theory in just proportion, which was not usually done at that time in books of this class; the tables of logarithms were issued separately in 1841 and 1851. He re-edited Hutton's Mathematical Recreations (1840, 1854). He also published some sixteen papers on astronomical subjects, of which eight are in the Philosophical Magazine, 1818–22, 1826, 1828, five in Memoirs of the Royal Astronomical Society, 1829, 1830, 1833, 1840, 1842, and three in Monthly Notices of the Royal Astronomical Society, 1833–9, 1845–7. The most important are those on chronometers (in which the author shows how to find the rates without the help of a transit instrument) (cf.
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On other occasions the company came third in the trials and did well enough for the Admiralty to buy a number of their chronometers. The Antarctic explorer Ernest Shackleton had a Reid & Sons chronometer. In 1858 William Ker Reid left the business having been an absent partner since 1812 when he had moved to London to set up his own company. On the death of David Reid Snr. in 1868 Christian John Reid ran the company with his brother David Reid Jr. (1832-1914, who retired from the company in 1882) and his sons Thomas Arthur Reid (1845-1910) and Walter Cecil Reid (1846-1933) in partnership with Francis James Langford at 41 Grey Street and 48 Grainger Street in Newcastle. Christian Leopold Reid (1872-1924) joined the partnership on the retirement of Walter Cecil Reid.
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Due to heavy surf they only stayed at Fernando de Noronha for a day to make the required observations, and Fitzroy decided to make for Bahia, Brazil, to rate the chronometers and take on water. On 28 February they reached the continent, arriving at the magnificent sight of the town now known as Salvador, with large ships at harbour scattered across the bay. On the next day, Darwin was in "transports of pleasure" walking by himself in the tropical forest, and in "long naturalizing walks" with others continued to "add raptures to the former raptures". He found the sights of slavery offensive and when FitzRoy defended the practice by describing a visit to a slaveowner whose slaves replied "no" on being asked by their master if they wished to be freed, Darwin suggested that answers in such circumstances were worthless.
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After World War I, Harrison's timepieces were rediscovered at the Royal Greenwich Observatory by retired naval officer Lieutenant Commander Rupert T. Gould. The timepieces were in a highly decrepit state and Gould spent many years documenting, repairing and restoring them, without compensation for his efforts. Gould was the first to designate the timepieces from H1 to H5, initially calling them No.1 to No.5. Unfortunately, Gould made modifications and repairs that would not pass today's standards of good museum conservation practice, although most Harrison scholars give Gould credit for having ensured that the historical artifacts survived as working mechanisms to the present time. Gould wrote The Marine Chronometer published in 1923, which covered the history of chronometers from the Middle Ages through to the 1920s, and which included detailed descriptions of Harrison's work and the subsequent evolution of the chronometer.
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From this, it can be seen that a navigator will need to know the time very accurately so that the position of the observed celestial body is known just as accurately. The position of the sun is given in degrees and minutes north or south of the equational or celestial equator and east or west of Greenwich, established by the English as the Prime Meridian. The desperate need for an accurate chronometer was finally met in the mid 18th century when an Englishman, John Harrison, produced a series of chronometers that culminated in his celebrated model H-4 that satisfied the requirements for a shipboard standard time-keeper. Many nations, such as France, have proposed their own reference longitudes as a standard, although the world’s navigators have generally come to accept the reference longitudes tabulated by the British.
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Pulkovo Observatory in 1839. During 1843 and 1844, Struve participated in longitude measurements between Altona, Greenwich and Pulkovo, which were based on large displacement of chronometers over the Earth surface. This newly developed method was adopted in Russia, and from 1844, the longitude was measured starting not from the Tartu Observatory but from the Pulkovo Observatory. Much of the 1844 Struve dedicated to studying the Sun. He deduced its apex coordinates and linear velocity as 7.3 km/s. Although it was significantly smaller than the correct value of 19.5 km/s measured in 1901, Struve's result was correct in that the velocity of the Sun was smaller than that of stars. In 1865 he discovered NGC 8, a double star in the constellation Pegasus. This occurred only 2 days after he discovered the spiral galaxy NGC 9 in the constellation Andromeda.
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While chronometers could deal with the conditions of a ship at sea, they could be vulnerable to the harsher conditions of land-based exploration and surveying, for example in the American North-West, and lunar distances were the main method used by surveyors such as David Thompson. Between January and May 1793 he took 34 observations at Cumberland House, Saskatchewan, obtaining a mean value of 102° 12' W, about 2' (2.2 km) east of the modern value. Sebert gives 102° 16' as the longitude of Cumberland House, but Old Cumberland House, still in use at that time, was 2km to the east, see: Each of the 34 observations would have required about 3 hours of calculation. These lunar distance calculations became substantially simpler in 1805, with the publication of tables using the Haversine method by Josef de Mendoza y Ríos.
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The differences in clock time between cities was not generally a problem until the advent of railroad travel in the 1800s, which both made travel between distant cities much faster than by walking or horse, and also required passengers to show up at specific times to meet their desired trains. In the United Kingdom, railroads gradually switched to Greenwich Mean Time (set from local time at the Greenwich observatory in London), followed by public clocks across the country generally, forming a single time zone. In the United States, railroads published schedules based on local time, then later based on standard time for that railroad (typically the local time at the railroad's headquarters), and then finally based on four standard time zones shared across all railroads, where neighboring zones differed by exactly one hour. At first railroad time was synchronized by portable chronometers, and then later by telegraph and radio signals.
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NOAA History: World War I Military Records of Coast & Geodetic Survey Personnel: Raymond S. Patton Patton was assigned to the U.S. Navy's Bureau of Navigation, with which he took up duty at the United States Naval Observatory in Washington, D.C., as Assistant in the Time Service and Nautical Instrument Division. He became chief of the division on 1 March 1918. The division was responsible for purchasing and distributing to U.S. Navy vessels all navigational instruments except compasses and compass fixtures; for the cleaning, compensation rating, and issue of all U.S. Navy marine chronometers; and with sending out the daily time signal by telegraph and radio. Before World War I broke out, the U.S. Navy had obtained most of its navigational instruments from foreign manufacturers, and their production in the United States had only become a major effort since then, making the division's efforts to procure such instruments in a timely manner a challenging task.
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Akvarel from the Mikhailov's album At 6 am on September 15, the vessels entered the harbor at Santa Cruz de Tenerife, where they stayed for six days. Simonov went with four officers from both sloops to the foot of the volcano Teide, explored the botanic garden with Dracaena dracos, and visited the sisters of general Agustín de Betancourt. However, the main responsibility of the astronomer was to verify the chronometers. For this purpose, he used the house of Captain Don Antonio Rodrigo Ruiz. A stock of wine was taken aboard at a price of 135 thaler for a butt. The expedition sailed across the Atlantic at a speed of between 5.5 and 7 knots, using the northwestern trade winds. They crossed the Tropic of Cancer on September 22, fixing the air temperature at noon at 20 ° Reaumur (25 °C). On September 25, Bellingshausen took advantage of the calm to change the topmast on Vostok in order to decrease its speed and help keep the two ships together'.
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The > verified longitude when abreast was somewhere between the two reckonings; > this was extraordinary. All navigators will tell you that from one day to > another a ship may lose or gain more than five miles in her sailing-account, > and again, in the matter of lunars, even expert lunarians are considered as > doing clever work when they average within eight miles of the truth... The > result of these observations naturally tickled my vanity, for I knew it was > something to stand on a great ship’s deck and with two assistants take lunar > observations approximately near the truth. As one of the poorest of American > sailors, I was proud of the little achievement alone on the sloop, even by > chance though it may have been... The work of the lunarian, though seldom > practised in these days of chronometers, is beautifully edifying, and there > is nothing in the realm of navigation that lifts one’s heart up more in > adoration.
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Born into a poor family in Linlithgowshire in Scotland, Bartholomew joined the Merchant Navy at a young age and became a highly experienced sailor, travelling to the Baltic Sea and the West Indies, working on hired merchant ships during campaigns against French islands there at the outbreak of the French Revolutionary Wars.. He later served on Greenland whalers, but in 1795 was seized by a press gang at Wapping and forcibly recruited into the Royal Navy. Due a superior education (although where he obtained this education is unknown), Bartholomew was rapidly promoted to midshipman, serving in numerous theatres and becoming a favourite of Admiral Sir Home Riggs Popham. Bartholomew was present at the surrender of the Dutch fleet in 1799, on HMS Romney in the East Indies and in 1802 was in charge of the ship's chronometers during a voyage to the Red Sea. The Peace of Amiens in the same year saw a reduction in the Navy and Bartholomew was placed in reserve.
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Thanks to the Surveying and Mapping Office Training School of the Lands Department of the HKSAR, the HIT Viewing Gallery has the 'Rifleman's Bolt', preserving a small but vital part of Hong Kong's maritime and general cartographic heritage. Generous donors and lenders have ensured that the museum's galleries are full of mementoes to Hong Kong's long, important, varied and intriguing maritime story – from the very first modern chart of Hong Kong (unknown until HKMM helped to identify it in 2007), through stunning arrays of ship portraits and ship models, to one of the earliest of the modern chronometers that opened up the modern globalised maritime world, and a windsurfer used by Hong Kong's Hayley Chan Hei Man () in the 2012 Olympic Games. The galleries have over 25 interactive screens using the latest technology to introduce visitors to the vast range of stories and topics at the heart of Hong Kong's – and the world's – maritime story.
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King joined as second lieutenant, sharing the duties of astronomer with Cook, taking astronomical observations on board by sextant and with Larcum Kendal's timekeeper K1, to establish the Resolutions position at sea and on shore by sextant or by astronomical quadrant to establish the geographical position of salient points during the course of Cook's surveys. Thus King's geographical positions were an important contribution to the accuracy of the various surveys carried out during the voyage and his use of the early chronometers helped prove their use at sea for calculation of Longitude. . Following the death of Cook, King remained in the Resolution but on the death of Charles Clerke, Cook's successor, King was appointed to command , the Resolutions consort, remaining in her for the rest of the voyage. After his return to England King was very much involved in the publication of the official account of Cook's third voyage, writing the third volume at Woodstock, near Oxford, where his brother Thomas was rector of St Mary Magdalene.
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After six weeks in the vicinity of Canton City, China, with the onset of the winter northeast monsoon and no sign of Boxer, Peacock sailed from Lintin Island in the Pearl River estuary for the bay of Turan (modern Danang) as best for access to Hué, capital of Cochin-China her task was to explore the possibilities of expanding trade with the kingdom. Contrary winds from the northwest rather than the expected northeast quarter, coupled with a strong southward current, caused her to lose ground on every tack until, on 6 January 1833, she entered what enquiries disclosed to be the Vung-lam harbour of Phu Yen province. On 8 February, Roberts having failed to gain permission to proceed to Hué due to miscommunication, Peacock weighed anchor for the gulf of Siam, where on the 18th she anchored about from the mouth of the river Menam at , as was ascertained by frequent lunar observations and by four chronometers. On 20 March 1833 Roberts concluded the Siamese-American Treaty of Amity and Commerce with the minister representing King Rama III, and Peacock departed on 5 April to call on Singapore, where she stayed between 1 and 11 May.
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Eclipse won the best-of-three heats competition. 60,000 spectators watched.(May 22, 2009) Racing to history, Daily Racing News, Retrieved November 15, 2010 ("May 27, 1823: A $20,000 match race between American Eclipse (representing The North) and Henry (representing The South) was held at Union Course, Long Island. Eclipse won in two-of-three heats, after his original jockey, William Crafts, was replaced by Samuel Purdy before the second heat. The race, witnessed by 60,000 spectators, was the first to have been timed by split-second chronometers, which were imported for the event.") Grimes, William (May 10, 2006). The Day Two Great Horses Foreshadowed the Civil War, The New York Times, Retrieved November 15, 2010 (May 31, 1908) Where the Ponies Run for the Masses, The New York Times, Retrieved November 12, 2010 (May 14, 1905) New York Racing Returns to Its Original Home, The New York Times, Retrieved November 12, 2010 In the 1830s, likely 1837, the Union Course became the first racecourse in America to have beveled turns, turned up on the outside, thus increasing speed on the course. The popularity of match races at Union Course gradually declined; after 1851, trotting races became the main attraction.
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