On the night of September 22-23, 1707, a British squadron under the command of Rear Admiral Claudsey Shovell, returning from the theater of operations of the War of the Spanish Succession, sat under full sail on the reefs off the Isles of Scilly, southwest of the Cornwall coast, just over 24 hours before returning home. The Isles of Scilly are part of the ancient Kornubian batholith, a granite massif from a fault eruption of the Carboniferous-Permian era, so the depth near their shores drops very sharply, and besides, they are the first land on the path of that branch of the Gulf Stream, which goes into the English Channel. Scilly is a very dangerous and treacherous area, where ships died regularly, but the scale of the shipwreck in 1707 was extremely large.
Five ships of the line and one fire-ship swooped down on the cliffs of Scilly's West Reef, barely visible above the water. Three ships sank, including the flagship of the Association Squadron, which sank with a crew of 800 in three minutes. Admiral Shovell himself drowned on the Association. The total number of victims of the disaster ranged from 1200 to 2000 people. Perhaps there would have been fewer casualties if sailors knew how to swim, but this skill was rare in the 18th century. Superstitious sailors believed that being able to swim meant being shipwrecked.
Subsequently, the legends blamed the admiral's aristocratic arrogance for the disaster, who allegedly ordered a sailor, a native of these places, to be hanged on a yacht, who informed him of the danger so that it would be discouraging to question the authority of his superiors. The reality was much more unpleasant: until the last moment, no one in the squadron had a clue that the ships were not where they were supposed to. Admiral Shovell, who passed all stages of the naval service, an honored sailor with 35 years of experience, and his navigators miscalculated their longitude due to bad weather and were sure that they were farther east, in the shipping area of the English Channel. The maps, on which the Isles of Scilly were at a distance of about 15 kilometers from their true position, were also summed up, which became known several decades later, already in the middle of the 18th century.
Shipwreck of Claudisly Shovell's squadron in 1707. Engraving by an unknown artist National Maritime Museum.
By the time of the Scilly catastrophe, the need for accurate methods for determining longitude had been recognized for more than a century. The era of geographical discoveries sharply demonstrated the lagging of cartographic methods from the needs of practice. The Spanish Habsburgs have offered awards for solving the "longitude problem" since 1567, Holland since 1600, and the French Academy of Sciences received such an assignment when it was created. The rewards were very generous - in 1598, Philip III of Spain promised 6,000 ducats at a time for a successful method of determining the longitude, 2,000 ducats for a lifetime annual pension, and 1,000 ducats for expenses. The ducat ("doge's coin"), equal to 3.5 grams of gold, was the international monetary equivalent, originally from Venice; The Habsburgs minted their ducats of the same weight. During this period, the entire volume of Venetian international trade was estimated at about two million ducats per year,and 15 thousand ducats cost the construction of a battle galley.
What was the "longitude problem"? It is difficult, but not impossible, to determine the latitude of a ship on the high seas to the nearest angular minute. Latitude is a fraction of the distance from the equator to the pole, and therefore the value is absolute. The angle between the earth's axis and the position of the ship can be determined both from the sun and from known stars using an astrolabe or sextant. Longitude is measured from a certain meridian and therefore is conditional: all points on the globe relative to the celestial sphere are equal, any point can be taken as zero. Near the coast, the location can be determined by the landmarks visible from the ship - mountains, rivers, towers, which have been marked on maps for this purpose since the time of the first portolans. Birds and plants can also indicate proximity to land. But in unfamiliar watersin the open ocean or in bad weather, the task of determining longitude became calculated. Out of caution, many ocean routes were laid not in a straight line from port to port, but along the coast of the continent to latitudes that were obviously free from dangerous reefs and islands, and from there along the geographical parallel to the opposite coast. Privateers and pirates often waited for their victims in these “navigable” latitudes (Dunn, Richard, Higgit, Rebeccah. Finding longitude. How ships, clocks and stars helped solve the longitude problem. Collins, 2014). Privateers and pirates often waited for their victims in these “navigable” latitudes (Dunn, Richard, Higgit, Rebeccah. Finding longitude. How ships, clocks and stars helped solve the longitude problem. Collins, 2014). Privateers and pirates often waited for their victims in these “navigable” latitudes (Dunn, Richard, Higgit, Rebeccah. Finding longitude. How ships, clocks and stars helped solve the longitude problem. Collins, 2014).
The method of reckoning, which was used by all sailors of this time, was based on measuring the speed of the ship and the time of its movement along a certain compass rumba. The speed was determined by a lag - a rope with knots, which was thrown overboard; the observers counted the number of knots that sailed past, and timed the time by counting or reciting the standard prayer "Our Father" or "Theotokos." Hence the speed "nautical mile per hour" was called "knot". The nautical mile itself is a measure of latitude - it is one arc-minute of the meridian. The resulting vector was plotted from the point where the movement began, taking into account the lateral drift from winds and currents - this is how the current coordinate was obtained. This method had a large error, which accumulated the more, the longer the ship was in the open sea. Accuracy of 50 kilometers in a transoceanic journey for this method is already a great success, mistakes of 100–150 kilometers were not uncommon even for experienced navigators.
The current longitude can be calculated accurately if you know the local time and the current astronomical time at the prime meridian (since 1960, the concept of "universal time" - UTC has been used). The current time is recorded by the sun at astronomical, or true, noon (the moment when the sun is highest). Astronomical noon is difficult to pinpoint exactly when it occurs, and in practice it is more often defined as the midpoint of the time span between the positions of the sun at the same altitude in the morning and afternoon. Since there are 1440 minutes in a day, and 21,600 arc minutes in a full circle, 1 arc minute corresponds to 4 seconds of time. By recalculating the difference between the local time and the time at the prime meridian in degrees, you can get a shift in longitude. But how to determine the time at the prime meridian?
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There are no landmarks fixed in longitude on the celestial sphere, but there are periodic ones. Eclipses of the Sun and Moon are the most convenient landmarks, but their rarity makes them inapplicable in periodic navigation, they were used to measure mainly the longitude of points on land. For example, the mapping of the Spanish New World took place: all local colonial administrators received the same sundial from Madrid in advance and were instructed to measure the exact position of the gnomon's shadow on the day of the eclipse. The collected coordinates were transferred to Madrid, where they were processed. The accuracy of such collective measurements was not high; some observers made errors of 2–5 degrees of longitude.
Eclipses of Jupiter's moons are much more common. Galileo, who opened them and very quickly realized that there was a natural celestial clock in front of him, even developed a celaton for this purpose - a bracket for attaching the telescope to the observer's head. But all attempts to see them from the ship, even in clear weather, were unsuccessful. But this method has been successfully used on land. It was used by Giovanni Cassini and Jean Picard to map France in the 1670s. As a result of the refined survey, the territory of France has shrunk on new maps so much that the Sun King is credited with saying "Astronomers have taken more lands from me than all the enemies put together."
Beginning in the 16th century, attempts were made to calculate or carefully describe the relative positions of the moon, sun and key navigational stars. This method of "lunar distances" assumed the determination of the angle between the Moon and other celestial bodies in the so-called "sea twilight" (before dawn and immediately after sunset, when both the stars and the horizon are visible at the same time). But at the beginning of the 18th century, the accuracy of this method was still too low, with an error of 2-3 degrees of longitude. It is with the attempt to improve the calculation of the lunar orbit, in order to correct the tables for navigators, that the formulation of the "three-body problem" (the Sun, the Earth and the Moon) is connected, which, as G. Bruns and A. Poincaré showed at the end of the 19th century, has no analytical solution in general view.
Cross-rod observations used to determine lunar distances and measure heights.
Finally, you can just look at the universal time on the clock synchronized with it. But for this, the watch must not lose its accuracy under conditions of rolling, changes in the Earth's gravitational and magnetic fields, high humidity and temperature jumps. Even on a stationary land, the task was difficult, and the finest minds of the 17th century made significant efforts to create quality watches.
By the beginning of the 18th century, stationary tower clocks with pendulums appeared, which were wrong by about 15 seconds per day. Their development became possible thanks to the research of Galileo Galilei, who discovered that the oscillations of a pendulum are constant in time (1601). In 1637, almost blind Galileo developed the first escapement (a device for swinging a pendulum), and in the 1640s his son tried to create a clock with a pendulum from his father's sketches, but to no avail.
The first workable and for its time very accurate pendulum clock was created in 1656 by Christian Huygens, who may have known about Galileo Jr.'s experiments from his father, a Dutch politician who took part in negotiations with Galileo Jr. (Gindikin S. G. Mathematical and mechanical problems in Huygens's works on pendulum clocks (Priroda, No. 12, 1979). Huygens, on the other hand, was the first to describe and substantiate an isochronous curve along which the pendulum will move at a constant speed, and added a pendulum controller to the clock based on it. Huygens gave a schematic diagram and mathematical justification for a clock with a pendulum in his treatise of 1673 "Horologium Oscillatorium: sive de motu pendulorum ad horologia aptato demostrationes geometricae"After some time, an anchor fork appears in the clock design, the purpose of which is to limit the oscillations of the pendulum to a small angle, since at large angles the property of isochronism of a straight pendulum disappears. The creation of the truss fork was often attributed to Robert Hooke or watchmaker George Graham, but now the priority is given to the astronomer and watchmaker Richard Townley, who created the first truss watch in 1676.
Christian Huygens.
At the same time, a breakthrough occurred in the creation of spring clocks. Hooke's famous studies of springs were aimed precisely at improving watch movements. The spring is used in balancers that control the accuracy of watches without pendulums; and it is believed that the first balancer was made by Hooke around 1657. In the 1670s, Huygens produced a modern type of coil spring balancer that enabled the creation of pocket watches (Headrick, Michael. Origin and Evolution of the Anchor Clock Escapement. Control Systems magazine, Inst. Of Electrical and Electronic Engineers. 22 (2), 2002).
At the end of the 18th century, previously made mechanical clocks began to be massively supplied with pendulums. The pendulum provided an accuracy much higher than that of a spring clock, but could only work on a flat surface and indoors. The pendulum was not suitable for long journeys, since humidity and temperature affect its length, and the roll knocks down the frequency of its oscillations. This became clear in the very first sea trials of the 1660s. And even under ideal conditions, the movement of the clock should take into account that the frequency of oscillations of a pendulum of constant length decreases as it approaches the equator - this phenomenon was discovered by the French astronomer Jean Richet, Cassini's assistant, in 1673 in Guyana.
It was this complex of problems that led to the fact that in 1714 the British Parliament passed a law on its own awards for the discovery of methods for determining longitude. On the recommendation of Isaac Newton and Edmund Halley, Parliament awarded a reward of £ 10,000 for 1 degree accuracy, £ 15,000 for 40 arc-minutes and 20,000 pounds for 30 arc-minutes. To determine the winners, parliament established the Commission for the Determination of Longitude at Sea, or, as it is often abbreviated as it is, the Commission for Longitude.
The early years of the British program were not particularly successful. The size of the first prize created a sensation in society, and the main cast of applicants for the prize included fraudsters and projectors, some of whom distinguished themselves during the boom of the South Seas in 1720. Only a few projects came from experienced scientists, mechanics and engineers and promoted problem understanding and problem solving. The law did not formalize the procedure for the commission's work and the procedure for awarding the prize, and the applicants besieged the members of the commission one by one according to their connections - some of the Lords of the Admiralty, some of the Astronomer Royal and the first head of the Greenwich Observatory, John Flamsteed, or Newton. The members of the commission either chased the applicants away, or reviewed their work in detail with recommendations for revising and changing the direction of the search, but in the first decades they did not offer any awards to anyone and,apparently did not even meet at the meeting.
The task looked so elusive that longitude seekers became the subject of ridicule. Jonathan Swift mentioned "longitude" along with "perpetual motion" and "panacea" in Gulliver's Travels (1730), and William Hogarth portrayed in the graphic novel "The Rake's Way" (1732) a madman drawing on the wall in Bedlam, the famous London house insane, longitude exploration projects. Some researchers believe that the politician and satirist John Arbuthnot wrote an entire book "The Longitude Examin'd" (late 1714), where he allegedly seriously described the project of the "vacuum chronometer" on behalf of a certain "Jeremy Tucker" (Rogers, Pat. Longitude forged. How an eighteenth-century hoax has taken in Dava Sobel and other historians. The Times Literary Supplement. November 12, 2008). Interestingly, even if this book is a satire,she not only shows a deep knowledge of mechanics and watchmaking, but also coined the term "chronometer" for the first time in history.
The most famous "longitude seeker" of the early period was nevertheless a rather serious scientist - William Whiston (1667-1752), a younger contemporary, colleague and popularizer of Newton. He replaced Newton as the head of the Lucas Chair in Cambridge, lost it due to the fact that he began to openly defend religious views close to Arianism (which Newton, close to him in views, sensibly did not do), and because of the same “heresies”he was not accepted into the Royal Society. After his expulsion from Cambridge, Whiston switched to the popularization of science, giving public lectures in London on the latest scientific advances. It was his report in early 1714 (co-authored with Humphrey Ditton) that was the impetus for the adoption of the law on longitude.
Long-haired madman. Detail of a painting by Hogarth from the Mota Career series.
When the award was announced, Whiston began to actively develop methods for determining longitude. In his activities, he used the new channels of mass communication available to him to form mass public support, namely, he advertised in newspapers, posted posters and spoke in coffee houses, which at that time were discussion clubs and public meeting rooms. Social networks and online media can serve as a rough analogy for the beginning of the 21st century. Whiston's social influence was so great that he was honored with personal satire from Martinus Scriblerus (a collective satirical project by A. Pope, J. Swift and J. Arbuthnot; in Russian literature, his close analogue is Kozma Prutkov). One of Whiston's projects described shipsanchored in the open sea at points with known coordinates and regularly firing signal flares into the air - this is the project that the madman in the picture of Hogarth drew on the wall.
Whiston considered the most promising determination of longitude by magnetic declination (this method was apparently first proposed by Edmund Halley). On this basis, Whiston clashed with Newton, through whom he submitted his projects and who regularly demanded that he engage in astronomical research instead of magnetic (For these and other Newton's reviews of projects in longitude, see: Cambridge University Library, Department of Manuscripts and University Archives. MS Add.3972 Papers on Finding the Longitude at Sea). As a result, Whiston made one of the first magnetic declination maps (it was a map of southern England). Ultimately the commission awarded Whiston an honorable mention of £ 500 for making instruments for measuring magnetic declination (1741). This was a dead-end branch of research: as we know now, after centuries of observation,The Earth's magnetic field changes very dynamically, and the magnetic declination cannot indicate the coordinates of a place.
Since 1732, an absolute leader gradually emerged in the search for methods for determining longitude - John Garrison (1693–1776), a London watchmaker. Harrison, a self-taught mechanic, developed several breakthrough innovations in his youth. He selected bakout wood (guaiac wood) for the watch bearings. Backout has high hardness and wear resistance, does not react to dampness, while also emitting natural lubricant, which, unlike watch lubricant of the 18th century, does not change its properties in the sea air (in the 19th-20th centuries, the backout proved to be excellent in bearings for propellers) … Thanks to bearings from the backout, Harrison's watch is still running. Garrison also created the first bimetallic pendulum in the form of parallel bars in steel and brass. The thermal expansion coefficient of these materials differs,so that when the temperature rises or falls, the total length does not change. The bimetallic pendulum could move from temperate latitudes to the tropics without changing the oscillation frequency except as a result of a change in the gravitational field. Garrison also developed an original trigger "grasshopper" mechanism (Michal, Stanislav. Clock. From gnomon to atomic clock. Transl. From Czech RE Melzer. M. 1983). These achievements in 1726 brought the young watchmaker the patronage of J. Graham, who passed on his experience to him, gave him money for work and presented his work to the Commission of Longitude. Garrison also developed an original trigger "grasshopper" mechanism (Michal, Stanislav. Clock. From gnomon to atomic clock. Transl. From Czech RE Melzer. M. 1983). These achievements in 1726 brought the young watchmaker the patronage of J. Graham, who passed on his experience to him, gave him money for work and presented his work to the Commission of Longitude. Garrison also developed an original trigger "grasshopper" mechanism (Michal, Stanislav. Clock. From gnomon to atomic clock. Transl. From Czech RE Melzer. M. 1983). These achievements in 1726 brought the young watchmaker the patronage of J. Graham, who passed on his experience to him, gave him money for work and presented his work to the Commission of Longitude.
By 1735, Garrison had assembled his first marine chronometer, which he called the H1 (a modern nomenclature proposed by the restorer Rupert Gould in the 1920s). The H1 was on display in Graham's workshop, where it was examined by members of the commission, the Royal Society and everyone else. The quality of workmanship, assembly and movement were so obvious and high that in 1736 Harrison and H1 went on a test voyage to Lisbon on the ship "Centurion". Although the H1 had gone bad at first, Garrison quickly got it back on track, and on the way back from Lisbon, Garrison's measurements prevented the Centurion from landing on the cliffs at Cape Lizard (Cornwell, near the Isles of Scilly). Following positive reports from the captain and navigators of the Centurion, the Admiralty demanded that the Longitude Commission be convened and Harrison be awarded the prize. The Commission met for the first time in many years and issued its first ever prize of £ 250 with the wording "for further work" (Howse, Derek. Britain's Board of Longitude: the finances, 1714-1828. The Mariner's Mirror, Vol. 84, No. 4, November 1998).
From that moment until 1760, Garrison became, in fact, the only grant recipient of the commission, which regularly met to inspect his new models and gave him money for further work, starting with the second grant in 1741 - 500 pounds at a time (at the same at the meeting, William Whiston also received the prize). Since then, Garrison has worked exclusively on chronometers and made claims to the commission that he was so busy with work on grants that he was deprived of the opportunity to earn a living and support his family (Confirmed minutes of the Board of Longitude. 4th of June, 1746. Cambridge University Library. RGO 14 /five). Perhaps this was an exaggeration characteristic of his era, since as a result of this "teardrop" Garrison received another grant of £ 500. Garrison was probably replenishing his budget,charging a fee for the demonstration of his inventions - it is known that Benjamin Franklin, who often visited London, paid 10 shillings and 6 pence (1 pound = 20 shillings = 240 pence) for the right to look at the chronometers in Harrison's workshop and was pleased with the amount spent. Harrison's public fame was great enough. In the post-Newton era, scientists enjoyed the attention and respect of society, and the dissemination of knowledge was greatly facilitated by the periodicals, supplemented by coffee shops, where information was transmitted by word of mouth, as in modern social networks. In 1749, Harrison was awarded the Copley Medal, established by the Royal Society in 1731.paid 10 shillings and 6 pence (1 pound = 20 shillings = 240 pence) for the right to watch the chronometers in Harrison's workshop and was pleased with the amount spent. Harrison's public fame was great enough. In the post-Newton era, scientists enjoyed the attention and respect of society, and the dissemination of knowledge was greatly facilitated by periodicals, supplemented by coffee shops, where information was passed by word of mouth, as in modern social networks. In 1749, Harrison was awarded the Copley Medal, established by the Royal Society in 1731.paid 10 shillings and 6 pence (1 pound = 20 shillings = 240 pence) for the right to watch the chronometers in Harrison's workshop and was pleased with the amount spent. Harrison's public fame was great enough. In the post-Newton era, scientists enjoyed the attention and respect of society, and the dissemination of knowledge was greatly facilitated by periodicals, supplemented by coffee shops, where information was passed by word of mouth, as in modern social networks. In 1749, Harrison was awarded the Copley Medal, established by the Royal Society in 1731. In 1749, Harrison was awarded the Copley Medal, established by the Royal Society in 1731. In 1749, Harrison was awarded the Copley Medal, established by the Royal Society in 1731.
John Garrison.
For the grants received from the commission, Garrison collected three more models of chronometers. H2 and H3 contained new innovative solutions. The most important of these are the first composite bearings with a cage and a bimetallic spring balancer to compensate for temperature surges. Leonardo da Vinci still has a schematic diagram of the bearing, but until H3 their practical application is unknown. But the breakthrough was made on the fourth model, H4. The H4 was made in the form of not a table clock, but a pocket "onion", and due to its small size, it used diamond and ruby bearings rather than bacout, but received a remontuar (winding mechanism) and a bimetallic balance bar of the H3 type. The H4 ran at five vibrations per second - much faster than any watch from the 18th century. Controlling slow vibrations was much easier than swift ones,but Garrison deliberately set the clock to oscillate at a frequency much higher than the ship's oscillation frequency in order to neutralize the vibrations of the hull and pitching, and he was not mistaken.
In 1761, immediately after the end of the naval threat from France during the Seven Years' War, H4 went on a test voyage to Port Royal in Jamaica with Harrison's son William, also a master mechanic, on the Deptford ship. H3 remained in Harrison's workshop. The error accumulated over 81 days was about five seconds, which meant an accuracy of 1.25 minutes - about 1 nautical mile for these latitudes. On the way back, William accurately predicted the appearance of Madeira. The enthusiastic captain of the "Deptford" wished to receive such a chronometer, and Garrison, who at that time was already 67 years old, appeared at the commission with a request to give him the first prize for fulfilling the requirements of the 1714 law.
The commission refused to issue a prize, citing the fact that the longitude of Port Royal may not be known accurately enough, luck may be accidental, and the chronometer is too expensive to be practical, that is, go into mass production. Garrison received an award of 1,500 pounds and a promise of another 1,000 pounds if a second test confirms that he was right. Garrison flew into a rage and launched a public campaign to pressure the commission. The reluctance to pay the commission was due not only to greed and caution, but also to the hopes that an alternative astronomical method would provide a solution to the problem in a less expensive way.
As Garrison worked on the watch, the instruments for observing celestial objects improved. In 1731, Oxford astronomy professor John Hadley (1682-1744), vice-president of the Royal Society, presented at a meeting of the society the Hadley quadrant (later called the "octant") - an instrument based on the combination of an object in a visor and another object reflected in a mirror … An arc of 45 degrees (one eighth of a circle, hence the name "octant") using mirrors allowed measuring angles twice as large, up to 90 degrees. Octant fixes the angle regardless of the movement of the observer and saves the result of observation even after its termination.
E. Halley took part in the sea trials of the Hadley octant, who after Flamsteed took over as head of the Greenwich Observatory. Halley for some reason did not remember that a similar reflective instrument was described in a letter to him around 1698 by Isaac Newton - these documents were found in Halley's archives many years later, along with a vivid description of how a high scientific commission on board the ship was fighting seasickness instead of observations.
John Hadley with octant in hand.
Independently of Hadley, a similar instrument was created by the American Thomas Godfrey (1704-1749). Hadley's instrument subsequently, with minor modifications, turned into an "octant", from which the sextants developed (with a scale of 60 ° and a measuring angle of 120 °). Despite all the practical importance of the tool, Hadley and Godfrey did not receive awards, but improved tools made it possible to find an alternative to watches.
In the 1750s, German astronomer Tobias Mayer (1723-1762), professor at the University of Göttingen, engaged in cartography of Germany, with the help of Leonard Euler (1707-1783), at that time professor at the University of Berlin, created especially accurate tables of the position of the moon. Euler proposed a theory of the motion of the moon, Mayer compiled lunar tables based on this theory and observations using a special instrument with a 360 ° view. Upon learning of the prize, Mayer at first did not dare to submit his tables to the commission, thinking that the foreigner would be refused immediately, but in the end he resorted to the patronage of the King of England and the Elector of Hanover, George II, and as a result his tables ended up in London. In 1761, the future head of the Greenwich Observatory, Neville Maskelyne (1732-1811), who traveled to Saint Helena to observe the passage of Venus in front of the solar disk,conducted tests of the method of "lunar distances" according to the Mayer tables with the Hadley octant and received a stable result with an accuracy of one and a half degrees.
A control voyage across the Atlantic from London to Bridgetown in Barbados was scheduled for 1763. In Barbados, Maskeline had to calculate the reference longitude from Jupiter's moons from solid earth. H4, Mayer tables and Christopher Irwin's "sea chair" on a stabilizing triaxial suspension for observing Jupiter's satellites were checked simultaneously. The chair, which its developer actively advertised through the London press, turned out to be useless, and Harrison's chronometer and "moon tables" ensured accuracy to half a degree. In the final report, the accuracy of the H4 chronometer was 9.8 nautical miles (15 km), or 40 seconds of longitude, the lunar distance method performed by Maskelyne and his assistant Charles Green - about half a degree.
In 1765, the commission met for a meeting, at which it decided to give Mayer's widow a reward of 5,000 pounds for the tables of her late husband, Euler - 300 pounds, and Harrison - 10 thousand pounds for success and another 10 thousand when the condition of "practicality" is met, that is the cost of the chronometer will be reduced, and its manufacturing technology will be described so that other watchmakers can reproduce it. Parliament, which approved the decisions of the commission, cut the remuneration for the "lunar tables" to 3,000 pounds, and deducted 2,500 pounds of grants already received from Harrison's award.
Garrison believed that he was stripped of the prize for the intrigues of Maskelein, who, almost simultaneously with the meeting of the commission, became the new Astronomer Royal and the head of the Greenwich Observatory (this was a coincidence, since the previous Astronomer Royal died suddenly). In this position, Maskelein became a member of the commission and head of the subcommittee on the state acceptance of chronometer technology. Models of watches with drawings and explanations of Harrison were transferred to Greenwich, where they were tested by Maskelein and representatives of the Admiralty for another 10 months. Based on the results of the tests, Maskelein expressed doubts that the chronometer gives stable results and can be used in the production version without parallel use of the "moon tables".
Maskelyne himself at this time with a team of Greenwich astronomers was preparing for publication the first "Nautical Almanac", which contained summary tables of the positions of the Sun, Moon, planets and "navigation stars" for a given longitude and latitude and the corresponding time values at zero. meridian for every day of the year. The first edition of the Almanac was published in 1767.
The first chronometer created in 1735.
Harrison, who was convinced that Maskelein was deliberately drowning his invention to give an advantage to astronomical methods, went to seek justice with the young King George III. The monarch, who had received a good scientific education, took the H5 chronometer for testing for himself and personally wound it up daily for six months. As a result of these tests, George III suggested that Garrison enter with a petition directly into parliament, bypassing the Longitude Commission, and demand his first prize, and if parliament refuses, then he, the king, will personally solemnly appear in parliament and demand the same from the throne. Parliament resisted for several more years, and as a result, in 1773, Harrison issued the last award of 8,750 pounds (after deducting costs and costs of materials).
The activities of the Longitude Commission resulted in:
The Longitude Commission worked until 1828, combining the functions of a grant organization and a research center, and issued a number of other awards and grants, including an award of 5,000 pounds to polar explorer W. Parry, who reached 82.45 ° north latitude in polar Canada at the beginning of the 19th century.
Summarizing this brief essay, one should once again draw attention to the fact that the solution to the problem of longitude was not achieved by one or even several breakthroughs, it was created long, hard, from a large number of steps, each of which was a significant achievement in its own field. Even after the Harrison chronometer and the Mayer-Euler method went from experiments to navigation practice, navigation and cartography methods continued to improve.
The leading role of science in Britain in solving navigation problems not only helped her to win and maintain the status of "ruler of the seas" (the early nationalist march "Rule Britain, by the seas" was complicated in 1740-1745), but also to establish Greenwich as the prime meridian, in the first a turn of quality nautical almanacs by Maskelein and his followers. The International Meridian Conference of 1884 in Washington adopted the Greenwich meridian as zero, which marked the beginning of the creation of the universal standard time system. Prior to this date, the discrepancy in the local time of different countries and even cities was such that it created serious problems, for example, for railway timetables. The last country that switched to coordinates according to Greenwich was France (1911), and the unification of time counting has not been completed to this day,which is well known to the people of Russia from the changing policy of summer time.
British chronometers were also considered the standard of quality among sailors of all countries at least until the middle of the 19th century. But although the counting of longitudes by chronometer was faster and more accurate than counting by "lunar distances", nautical almanacs held their positions throughout the 19th century. Chronometers were far from being on all ships back in the middle of the 19th century because of their high cost. In addition, the sailors very quickly figured out that there should have been at least three chronometers on the ship so that errors in their readings could be detected and eliminated. If two of the three chronometers show the same time, it is clear that the third is wrong and how much he is wrong (this is the first known example of triple modular redundancy). But even in this case, the chronometer readings were checked against astronomical data. “… Venerable Stepan Ilyich hastily finishes his third glass,finishes the second thick cigarette and goes upstairs with a sextant to take the heights of the sun to determine the longitude of the place "- this is how K. Stanyukovich described the work of a naval navigator in the early 1860s, despite the fact that the ship was equipped with several chronometers.
By the beginning of the 20th century, chronometers reached an accuracy of 0.1 seconds per day, thanks to discoveries in metallurgy and materials science. In 1896, Charles Guillaume created iron-nickel alloys, with minimal coefficients of thermal expansion (invar) and thermoelasticity (elinvar), which were matched to compensate each other in pairs. This is how a high-quality material for the spring and the balance wheel wheel appeared (in 1920 Guillaume received the Nobel Prize in physics for these works). Modern analogues of Invar and Elinvar also include beryllium.
With the invention of radio, terrestrial radio stations began to transmit their coordinates. By the beginning of the First World War, the need for a lunar distance method disappeared, and timekeeping became an additional control method. At the same time, a new, better quality harmonic oscillator was found than a pendulum or a spring balancer. In 1880 Pierre and Jacques Curie discovered the piezoelectric properties of quartz, and in 1921 Walter Cady developed the first quartz resonator. This is how the technological foundation for the creation of quartz watches appeared, which were initially used as sources of accurate time signals, and since the 1960s have become mass instruments. Marine chronometers began to be supplanted by electronic watches.
With the beginning of the space age, navigation took the next step. It is interesting that the basic scheme of satellite navigation is basically no different from Whiston's proposal to place stationary ships at sea, according to the signals of which the mariners will determine their coordinates - these are satellites that broadcast their coordinates and universal time to signal receivers on Earth. Technologies of the 20th century made it possible to implement the plans of the 18th century at a new level. From 1972 to 1990, an orbital constellation of GPS navigation satellites was created, which in 1992 was opened for civilian use. Since 2011, the Soviet-Russian GLONASS has reached its design capacity, and two more systems are being prepared for launch, the European (Galileo) and Chinese (Beidou). The ultimate accuracy of these systems is measured in meters. Satellites are also used in several modern geodetic systems, the largest of which, the French DORIS, has centimeter accuracy. Smartphones of the 2010s began to include simple navigation systems linked to satellites with an accuracy of 8 to 32 meters and an automatic time synchronization function using signals from cellular operators and Internet resources of "atomic time".
Nevertheless, the calculation of coordinates "along the Moon" only in the XX century began to be excluded from the training programs for sailors, and nautical almanacs are still being published. This is a very appropriate safety net. If an electrician fails on a ship, the sailor should not lose his navigation aids. But even not knowing how to handle the sextant and almanac, the sailor (and anyone who has finished reading this article) will be able to determine their coordinates with an accuracy of a fraction of a degree, using a wrist watch and a shadow from any vertical object. The technological progress of recent centuries has made it possible to wear on the hand, if not a chronometer, then a rather close resemblance to it.
Author: Yuri Ammosov
