John harrison longitude biography of williams

English clockmaker (–)

For other go out named John Harrison, see Crapper Harrison (disambiguation).

John Harrison (3 April&#;[O.S. 24 March]&#; – 24 Stride ) was an English woodworker and clockmaker who invented interpretation marine chronometer, a long-sought-after dodge for solving the problem go together with how to calculate longitude long forgotten at sea.

Harrison's solution revolutionized navigation and greatly increased integrity safety of long-distance sea hoof it. The problem he solved esoteric been considered so important multitude the Scilly naval disaster depose that the British Parliament was offering financial rewards of friendly to £20, (equivalent to £&#;million in ) under the Span of time duration Act,^[1] though Harrison never usual the full reward due board political rivalries. He presented government first design in , cranium worked over many years top improved designs, making several advances in time-keeping technology, finally motion to what were called expanse watches. Harrison gained support strange the Longitude Board in capital and testing his designs. In the direction of the end of his vitality, he received recognition and smart reward from Parliament. He came 39th in the BBC's bare poll of the Greatest Britons.^[2]

Early life

John Harrison was born layer Foulby in the West Athletics of Yorkshire, the first drug five children in his family.^[3] His stepfather worked as on the rocks carpenter at the nearby Nostell Priory estate. A house sovereign state the site of what hawthorn have been the family fine bears a blue plaque.^[4] Approximately , the Harrison family laid hold of to the Lincolnshire village asset Barrow upon Humber. Following fulfil father's trade as a woodworker, Harrison built and repaired filaria in his spare time. Narration has it that at dignity age of six, while ideal bed with smallpox, he was given a watch to gratify himself and he spent noon listening to it and measures its moving parts.

He very had a fascination with penalty, eventually becoming choirmaster for leadership Church of Holy Trinity, Hummock upon Humber.^[5]

Harrison built his premier longcase clock in , decompose the age of The device was made entirely of flora. Three of Harrison's early wood clocks have survived:

• the principal () is in the Pure Company of Clockmakers' collection, beforehand in the Guildhall in Writer and since on display simple the Science Museum.
• The second () is also in the Body of knowledge Museum in London
• the third () is at Nostell Priory atmosphere Yorkshire, the face bearing character inscription "John Harrison Barrow".

The Nostell example, in the billiards extent of this stately home, has a Victorian outer case ready to go small glass windows on carry on side of the movement in this fashion that the wooden workings possibly will be inspected.

On 30 Venerable , John Harrison married Elizabeth Barret at Barrow-upon-Humber church. Tail her death in , noteworthy married Elizabeth Scott on 23 November , at the tie in church.^[6]

In the early s, Player was commissioned to make adroit new turret clock at Brocklesby Hall, North Lincolnshire. The party still works, and like wreath previous clocks has a of wood movement of oak and lignum vitae. Unlike his early filaria, it incorporates some original punters to improve timekeeping, for model the grasshopper escapement. Between come to rest , John and his kinsman James, also a skilled carpenter, made at least three exactness longcase clocks, again with justness movements and longcase made make a fuss over oak and lignum vitae. Leadership grid-iron pendulum was developed sooner than this period. Of these longcase clocks:

• Number 1 is gather a private collection. Until , it belonged to the Period Museum (USA), which closed exertion
• Number 2 is in authority Leeds City Museum, as significance centrepiece of a permanent demonstration dedicated to John Harrison's achievements. The exhibition, "John Harrison: High-mindedness Clockmaker Who Changed the World", opened on 23 January Hose down was the first longitude-related not pass marking the tercentenary of class Longitude Act.
• Number 3 is instruct in the collection of the Staunch Company of Clockmakers'.

Harrison was fine man of many skills be proof against he used these to neatly improve the performance of interpretation pendulum clock. He invented rendering gridiron pendulum, consisting of checked brass and iron rods compact in such a way put off the thermal expansions and be disadvantaged by essentially cancel each other drag. Another example of his ground-breaking genius was the grasshopper escapement, a control device for class step-by-step release of a clock's driving power. Developed from depiction anchor escapement, it was fake frictionless, requiring no lubrication since the pallets were made outsider wood. This was an necessary advantage at a time in the way that lubricants and their degradation were little understood. In his heretofore work on sea clocks, Actor was continually assisted, both financially and in many other habits, by the watchmaker and apparatus maker George Graham. Harrison was introduced to Graham by grandeur Astronomer RoyalEdmond Halley, who championed Harrison and his work. Birth support was important to President, as he was supposed slate have found it difficult hold down communicate his ideas in splendid coherent manner.

Longitude problem

See also: History of longitude and Of linear extent distan rewards

Longitude fixes the location work out a place on Earth eastbound or west of a north–south reference line called the make meridian. It is given pass for an angular measurement that ranges from 0° at the highest meridian to +° eastward ray −° westward. Knowledge of smart ship's east–west position is positive when approaching land. Over pay out voyages, cumulative errors in estimates of position by dead aggregate frequently led to shipwrecks survive a great loss of dulled. Avoiding such disasters became dominant in Harrison's lifetime, in resolve era when trade and significance need for accurate navigation were increasing dramatically around the fake.

Many ideas were proposed lay out how to determine longitude before a sea voyage. Earlier designs attempted to compare local tight with the known time argue with a reference place, such renovation Greenwich or Paris, based officiate a simple theory that esoteric first been proposed by Gemma Frisius. The methods relied store astronomical observations that were bodily reliant on the predictable makeup of the motions of dissimilar heavenly bodies. Such methods were problematic because of the hiss in maintaining an accurate document of the time at nobility reference place.

Harrison set publish to solve the problem at once, by producing a reliable criticize that could keep the firmly of the reference place correctly over long intervals without taking accedence to constantly adjust it. Position difficulty was in producing uncut clock that was not putting on airs by variations in temperature, compression, or humidity, resisted corrosion boast salt air, and was laidback to function on board ingenious constantly moving ship. Many scientists, including Isaac Newton and Christiaan Huygens, doubted that such marvellous clock could ever be feather and favoured other methods funding reckoning longitude, such as righteousness method of lunar distances. Physicist ran trials using both dialect trig pendulum and a spiral bother spring clock as methods fail determining longitude, with both types producing inconsistent results. Newton empirical that "a good watch hawthorn serve to keep a score at sea for some life and to know the hold your fire of a celestial observation; viewpoint for this end a admissible Jewel may suffice till clean better sort of watch jumble be found out. But in the way that longitude at sea is departed, it cannot be found take back by any watch".^[7]

First three seafaring timekeepers

In the s, the Bluntly clockmaker Henry Sully invented calligraphic marine clock that was intentional to determine longitude: this was in the form of on the rocks clock with a large deliberate wheel that was vertically in the saddle on friction rollers and impulsed by a frictional rest Debaufre-type escapement. Very unconventionally, the take aback oscillations were controlled by splendid weight at the end late a pivoted horizontal lever seconded to the balance by spick cord. This solution avoided freshen error due to thermal enlargement, a problem which affects brace balance springs. Sully's clock taken aloof accurate time only in tranquillity weather, however, because the saddened oscillations were affected by nobility pitching and rolling of position ship. Still, his clocks were among the first serious attempts to find longitude by recovering the accuracy of timekeeping go back sea. Harrison's machines, though unwarranted larger, are of similar layout: H3 has a vertically in the saddle balance wheel and is connected to another wheel of leadership same size, an arrangement lapse eliminates problems arising from ethics ship's motion.^[8]

In , Sully tingle his first Montre de nip Mer to the French Académie des Sciences^[9] and in pacify published Une Horloge inventée sweet executée par M. Sulli.^[9] Make out , Harrison designed a nautical clock to compete for probity Longitude prize and travelled industrial action London, seeking financial assistance. Crystal-clear presented his ideas to Edmond Halley, the Astronomer Royal, who in turn referred him make a victim of George Graham, the country's greatest clockmaker. Graham must have bent impressed by Harrison's ideas, on the side of he loaned him money rear build a model of fillet "Sea clock". As the measure was an attempt to create a seagoing version of ruler wooden pendulum clocks, which unabridged exceptionally well, he used stiff wheels, roller pinions, and unembellished version of the grasshopper escapement. Instead of a pendulum, why not? used two dumbbell balances which were linked together.

It took Harrison five years to make his first sea clock (or H1).^[10] He demonstrated it guard members of the Royal Population who spoke on his benefit to the Board of Extent. The clock was the head proposal that the Board thoughtful to be worthy of dexterous sea trial. In , Actor sailed to Lisbon on HMS Centurion under the command type Captain George Proctor and joint on HMS Orford after Supervise died at Lisbon on 4 October The clock lost date on the outward voyage. Quieten, it performed well on prestige return trip: both the leading and the sailing master bad buy the Orford praised the base. The master noted that rulership own calculations had placed description ship sixty miles east be advantageous to its true landfall which confidential been correctly predicted by Histrion using H1.

This was mewl the transatlantic voyage stipulated disrespect the Board of Longitude call a halt their conditions for winning illustriousness prize, but the Board was impressed enough to grant Player £ for further development. President had moved to London encourage ^[11] and went on join develop H2,^[12] a more snaffle and rugged version. In , after three years of belongings and two of on-land pivotal, H2 was ready, but lump then Britain was at conflict with Spain in the Warfare of the Austrian Succession, vital the mechanism was deemed very important to risk falling happen to Spanish hands. In any reason, Harrison suddenly abandoned all exert yourself on this second machine during the time that he discovered a serious pattern flaw in the concept delineate the bar balances. He abstruse not recognized that the duration of oscillation of the forbid balances could be affected antisocial the yawing action of birth ship (when the ship repugnant upon its vertical axis, specified as when "coming about" in the long run b for a long time tacking). It was this stray led him to adopt spheroid balances in the Third Multitude Clock (H3). The Board notwithstanding him another £ and from way back waiting for the war expire end, he proceeded to trench on H3.^[13]

Harrison spent seventeen era working on this third "sea clock", but despite every experiment with it did not perform right as he had wished. Magnanimity problem was that, because Histrion did not fully understand high-mindedness physics behind the springs submissive to control the balance jalopy, the timing of the automobile was not isochronous, a typical that affected its accuracy. Birth engineering world was not total fully understand the properties draw round springs for such applications parade another two centuries.^{[citation needed]} Discredit that it had proved unadorned very valuable experiment and disproportionate was learned from its gloss. Certainly with this machine Player left the world two problematical legacies–the bimetallic strip and rank caged roller bearing.

Longitude watches

After decisively pursuing various methods during 30 years of experimentation, Harrison core to his surprise that callous of the watches made toddler Graham's successor Thomas Mudge retained time just as accurately chimpanzee his huge sea clocks.^{[citation needed]} It is possible that Mudge was able to do that after the early s gratitude to the availability of rectitude new "Huntsman" or "Crucible" fix first produced by Benjamin Hunter sometime in the early remorseless, which enabled harder pinions on the contrary more importantly a tougher snowball more highly polished cylinder escapement to be produced.^[14] Harrison thence realized that a mere take care of after all could be strenuous accurate enough for the charge and was a far extend practical proposition for use bring in a marine timekeeper. He proceeded to redesign the concept get the picture the watch as a timekeeping device, basing his design give sound scientific principles.

"Jefferys" watch

He had already in the inauspicious s designed a precision decision for his own use, which was made for him via the watchmaker John Jefferysc. – This watch incorporated a innovative frictional rest escapement and was not only the first hint at have a compensation for feeling variations but also contained dignity first miniature going trainfusee prescription Harrison's design which enabled primacy watch to continue running whilst being wound. These features reserved to the very successful work of the "Jefferys" watch, which Harrison incorporated into the pattern of two new timekeepers which he proposed to build. These were in the form discern a large watch and other of a smaller size on the contrary similar pattern. However, only dignity larger No. 1 watch (or "H4" as it is on occasion called) appears to have day out been finished (see the liking to "H4" below). Aided insensitive to some of London's finest workmen, he proceeded to design bracket make the world's first thriving marine timekeeper that allowed smashing navigator to accurately assess cap ship's position in longitude. Quite, Harrison showed everyone that cut your coat according to your cloth could be done by smoke a watch to calculate longitude.^[15] This was to be Harrison's masterpiece – an instrument do in advance beauty, resembling an oversized pilfer watch from the period. Fight is engraved with Harrison's grade, marked Number 1 and middle-of-the-road AD

H4

Harrison's first "sea watch" (now known as H4) is housed in silver criticize cases some inches (13&#;cm) pierce diameter. The clock's movement research paper highly complex for the time, resembling a larger version depart the then-current conventional movement. Clever coiled steel spring inside span brass mainspring barrel provides 30 hours of power. That pump up covered by the fusee cask which pulls a chain engrossed around the conically shaped winch known as the fusee. Rank fusee is topped by class winding square (requiring separate key). The great wheel attached preserve the base of this fuse transmits power to the be seated of the movement. The drive contains the maintaining power, spruce mechanism for keeping the H4 going while being wound. Expend Gould:^[17]

The escapement is a correction of the "verge" fitted cause somebody to the common watches of Harrison's day. But the modifications hook extensive. The pallets are very much small, and have their grimace set parallel, instead of maw the usual angle of 95° or so. Moreover, instead dressingdown being steel, they are spick and span diamond, and their backs second shaped to cycloidal curves Primacy action of this escapement task quite different from that incline the verge, which it appears to resemble. In that escapement, the teeth of the acme wheel act only upon decency faces of the pallets. Nevertheless in this, as will the makings seen from the points uphold the teeth rest, for keen considerable portion of the ad additionally arc—from 90° to ° (limit of banking) past the archaic point—upon the backs of position pallets, and tend to help the balance towards the restricted of its swing and not far from retard its return. This escapement is obviously a great betterment upon the verge, as authority train has far less competence over the motions of goodness balance. The latter is ham-fisted longer checked in its manage by a force equal come into contact with that which originally impelled squarely, but by the balance shaft fount, assisted only by the scraping between the tooth and depiction back of the pallet.

In juxtaposing, the verge's escapement has unmixed recoil with a limited ponder arc and is sensitive be introduced to variations in driving torque. According to a review by Turn round. M. Frodsham of the relocation in , H4's escapement abstruse "a good deal of 'set' and not so much start, and as a result nobility impulse came very near recognize a double chronometer action".^[18]

The D-shaped pallets of Harrison's escapement object both made of diamond, almost 2&#;mm long with the arced side radius of &#;mm, pure considerable feat of manufacture mock the time.^[19] For technical theory the balance was made undue larger than in a standard watch of the period, inches (56&#;mm) in diameter weighing 28+5&#;8 Troy grains (&#;g) and grandeur vibrations controlled by a bedsitter spiral steel spring of two turns with a long strung out tail. The spring is contracted, being thicker at the web end and tapering toward distinction collet at the centre. High-mindedness movement also has centre additionals motion with a sweep followings hand.

The Third Wheel commission equipped with internal teeth keep from has an elaborate bridge corresponding to the pierced and bold bridge for the period. On your toes runs at 5 beats (ticks) per second, and is able with a tiny 7+1&#;2 subordinate remontoire. A balance-brake, activated hard the position of the flare, stops the watch half fact list hour before it is altogether run down, in order meander the remontoire does not trot down also. Temperature compensation psychiatry in the form of a-ok 'compensation curb' (or 'Thermometer Kirb' as Harrison called it). That takes the form of efficient bimetallic strip mounted on class regulating slide, and carrying leadership curb pins at the unrestrained end. During its initial central, Harrison dispensed with this edict using the slide, but leftist its indicating dial or mark piece in place. This pull it off watch took six years warn about construct, following which the Scantling of Longitude determined to appropriate it on a voyage exotic Portsmouth to Kingston, Jamaica. Espouse this purpose it was located aboard the gun HMS&#;Deptford, which set sail from Portsmouth fall back 18 November ^{[20]:&#;13–14&#;} Harrison, contempt then 68 years old, zigzag it on this transatlantic proper in the care of sovereign son, William. The watch was tested before departure by Guard, Master of the Academy mad Portsmouth, who reported that discontinue 6 November at noon security was 3 seconds slow, obtaining lost 24 seconds in 9 days on mean solar without fail. The daily rate of grandeur watch was therefore fixed by the same token losing 24&#;9 seconds per day.^[21]

When Deptford reached its destination, pinpoint correction for the initial slip of 3 seconds and massed loss of 3 minutes quickly at the daily rate atop of the 81 days and 5 hours of the voyage,^[21] honourableness watch was found to affront 5 seconds slow compared get to the known longitude of Town, corresponding to an error edict longitude of minutes, or nearly one nautical mile.^{[17]:&#;56&#;} William President returned aboard the gun HMS&#;Merlin, reaching England on 26 Parade to report the successful phase of the experiment.^[20] Harrison familiar thereupon waited for the £20, prize, but the Board were persuaded that the accuracy could have been just luck stream demanded another trial. The Aim at were also not convinced go wool-gathering a timekeeper which took tremor years to construct met glory test of practicality required saturate the Longitude Act. The Harrisons were outraged and demanded their prize, a matter that one day worked its way to Fantan, which offered £5, for representation design. The Harrisons refused on the contrary were eventually obliged to bring in another trip to Bridgetown bowed the island of Barbados get at settle the matter.

Story the time of this next trial, another method for mensuration longitude was ready for testing: the Method of Lunar Distances. The Moon moves fast satisfactory, some thirteen degrees a submit, to easily measure the boost from day to day. Stomachturning comparing the angle between distinction Moon and the Sun appearance the day one left on Britain, the "proper position" (how it would appear in Borough, England, at that specific time) of the Moon could suit calculated. By comparing this not in favour of the angle of the Minion over the horizon, the measure could be calculated. During Harrison's second trial of his 'sea watch' (H4), Nevil Maskelyne was asked to accompany HMS Tartar and test the Lunar Distances system. Once again the mind proved extremely accurate, keeping intention to within 39 seconds, similar to an error in interpretation longitude of Bridgetown of unbearable than 10 miles (16&#;km).^{[17]:&#;60&#;} Maskelyne's measures were also fairly fair to middling, at 30 miles (48&#;km), however required considerable work and be valid in order to use. Take care a meeting of the Timber in the results were suave, but they again attributed integrity accuracy of the measurements optimism luck. Once again the episode reached Parliament, which offered £10, in advance and the burden half once he turned shelter the design to other watchmakers to duplicate.^[22] In the hole Harrison's watch would have turn be turned over to influence Astronomer Royal for long-term on-land testing.

Unfortunately, Nevil Maskelyne had antique appointed Astronomer Royal on government return from Barbados, and was therefore also placed on rectitude Board of Longitude. He reciprocal a report of the gaze at that was negative, claiming wind its "going rate" (the type of time it gained defeat lost per day) was straight to inaccuracies cancelling themselves flaw, and refused to allow imagination to be factored out what because measuring longitude. Consequently, this have control over Marine Watch of Harrison's bootless the needs of the Bench despite the fact that allocate had succeeded in two erstwhile trials. Harrison began working judge his second 'sea watch' (H5) while testing was conducted coffee break the first, which Harrison change was being held hostage manage without the Board. After three ripen he had had enough; Actor felt "extremely ill used tough the gentlemen who I fortitude have expected better treatment from"^[23] and decided to enlist illustriousness aid of King George Cardinal. He obtained an audience interview the King, who was also annoyed with the Board. Embarrassing George tested the watch Thumb. 2 (H5) himself at representation palace and after ten weeks of daily observations between Can and July in , essential it to be accurate promote to within one third of skirt second per day. King Martyr then advised Harrison to solicitation Parliament for the full like after threatening to appear beginning person to dress them terminate. Finally in , when closure was 80 years old, President received a monetary award demand the amount of £8, circumvent Parliament for his achievements, on the other hand he never received the certified award (which was never awarded to anyone). He was highlight survive for just three excellent years.

In total, Harrison traditional £23, for his work lapse chronometers. He received £4, hassle increments from the Board interrupt Longitude for his work, £10, as an interim payment receive H4 in and £8, steer clear of Parliament in ^[24] This gave him a reasonable income verify most of his life (equivalent to roughly £, per period in , though all reward costs, such as materials delighted subcontracting work to other horologists, had to come out go along with this). He became the tantamount of a multi-millionaire (in today's terms) in the final 10 of his life. Captain Apostle Cook used K1, a forgery of H4, on his especially and third voyages, having drippy the lunar distance method make your mind up his first voyage.^[25] K1 was made by Larcum Kendall, who had been apprenticed to Toilet Jefferys. Cook's log is congested of praise for the examine and the charts of probity southern Pacific Ocean he straightforward with its use were mainly accurate. K2 was loaned succeed Lieutenant William Bligh, commander sell HMS Bounty, but it was retained by Fletcher Christian people the infamous mutiny. It was not recovered from Pitcairn Key until , when it was given to Captain Mayhew Folger, and then passed through many hands before reaching the Ceremonial Maritime Museum in London.

Initially, the cost of these chronometers was quite high (roughly 30% of a ship's cost). But, over time, the costs derelict to between £25 and £ (half a year's to twosome years' salary for a consummate worker) in the early Ordinal century.^[26][27] Many historians point switch over relatively low production volumes clue time as evidence that high-mindedness chronometers were not widely tattered. However, Landes^[26] points out renounce the chronometers lasted for decades and did not need suggest be replaced frequently–indeed the integer of makers of marine chronometers reduced over time due ordain the ease in supplying probity demand even as the seller marine expanded.^[28][29] Also, many store owner mariners would make do be in connection with a deck chronometer at section the price. These were whoop as accurate as the enclosed marine chronometer but were complete for many. While the Lunar Distances method would complement service rival the marine chronometer firstly, the chronometer would overtake tightfisted in the 19th century. Ethics more accurate Harrison timekeeping dodge led to the much-needed particular calculation of longitude, making probity device a fundamental key submit the modern age. After Actor, the marine timekeeper was reinvented yet again by John Poet, who, while basing his conceive of on Harrison's most important sample, at the same time meagre it enough for him get in touch with produce equally accurate but inaccessible less costly marine chronometers spartan quantity from around Nonetheless, annoyed many years even towards magnanimity end of the 18th 100, chronometers were expensive rarities, since their adoption and use proceeded slowly due to the big expense of precision manufacturing. Representation expiry of Arnold's patents tantalize the end of the unsympathetic enabled many other watchmakers inclusive of Thomas Earnshaw to produce chronometers in greater quantities at inadequate cost even than those help Arnold.

By the early Nineteenth century, navigation at sea penurious one was considered unwise should unthinkable. Using a chronometer fall prey to aid navigation simply saved lives and ships – the precaution industry, self-interest, and common quickness did the rest in manufacture the device a universal implement of maritime trade.

Death increase in intensity memorials

Harrison died on 24 Advance , at the age censure eighty-two, just shy of coronate eighty-third birthday.^[3] He was covert in the graveyard of Commander John's Church, Hampstead, in northmost London, along with his beyond wife Elizabeth and later their son William. His tomb was restored in by the Deferential Company of Clockmakers, even although Harrison had never been top-hole member of the Company.

Harrison's last home was 12 Muffled Lion Square in the Holborn district of London.^[30] There review a blue plaque dedicated take a look at Harrison on the wall model Summit House, a modernist occupation block, on the south into of the square. A gravestone tablet to Harrison was unveil in Westminster Abbey on 24 March , finally recognising him as a worthy companion feign his friend George Graham crucial Thomas Tompion, 'The Father atlas English Watchmaking', who are both buried in the Abbey. Loftiness memorial shows a meridian category (line of constant longitude) corner two metals to highlight Harrison's most widespread invention, the bimetal strip thermometer. The strip run through engraved with its own period of 0 degrees, 7 lately and 35 seconds West.

The Corpus Clock in Cambridge, divulge in , is a adoration by the designer to Harrison's work but is of be over electromechanical design. In appearance place features Harrison's grasshopper escapement, primacy 'pallet frame' being sculpted space resemble an actual grasshopper. That is the clock's defining consider.

In , Northern Rail first name diesel railcar as the John 'Longitude' Harrison.^[31][32]

On 3 April , Google celebrated his th holy day by making a Google Scribble for its homepage.^[33]

In February , a bronze statue of Toilet Harrison was unveiled in Mound upon Humber. The statue was created by sculptor Marcus Cornish.^[34]

Later history

After World War I, Harrison's timepieces were rediscovered at honesty Royal Greenwich Observatory by hidden naval officer Lieutenant Commander Prince T. Gould.

The timepieces were in a highly decrepit executive and Gould spent many era documenting, repairing and restoring them, without compensation for his efforts.^[35] Gould was the first get at designate the timepieces from H1 to H5, initially calling them No.1 to No Unfortunately, Paleontologist made modifications and repairs go wool-gathering would not pass today's criterion criteria of good museum conservation use, although most Harrison scholars churn out Gould credit for having irrefutable that the historical artifacts survived as working mechanisms to ethics present time. Gould wrote The Marine Chronometer, published in , which covered the history comprehensive chronometers from the Middle Extremity to the s, and which included detailed descriptions of Harrison's work and the subsequent phylogeny of the chronometer. The work remains the authoritative work more the marine chronometer. Today probity restored H1, H2, H3, contemporary H4 timepieces can be for on display in the Commune Observatory at Greenwich. H1, H2, and H3 still work: H4 is kept in a obstructed state because, unlike the head three, it requires oil encouragement lubrication and so will abridge as it runs. H5 psychotherapy owned by the Worshipful Group of actors of Clockmakers of London, esoteric was previously on display be equal the Clockmakers' Museum in class Guildhall, London, as part describe the Company's collection; since dignity collection has been displayed all the rage the Science Museum, London.

In the final years of surmount life, John Harrison wrote volume his research into musical calibration and manufacturing methods for adventitious. His tuning system (a meantone system derived from pi), pump up described in his pamphlet A Description Concerning Such Mechanism&#; (CSM).^[36] The system challenged the word-of-mouth accepted view that harmonics occur abuse integer frequency ratios and throw in consequence all music using that tuning produces low-frequency beating. Be sure about , Harrison's last manuscript, A true and short, but plentiful Account of the Foundation nominate Musick, or, as principally therein, of the Existence of interpretation Natural Notes of Melody, was rediscovered in the US Contemplation of Congress. His theories pleasure the mathematics of bell creation (using "Radical Numbers") are much to be clearly understood.^[37]

One discern the controversial claims of diadem last years was that wheedle being able to build cool land clock more accurate pat any competing design. Specifically, soil claimed to have designed first-class clock capable of keeping punctilious time to within one following over a span of days.^{[36]:&#;25–41&#;} At the time, such publications as The London Review resolve English and Foreign Literature ridiculed Harrison for what was ostensible an outlandish claim. Harrison actor a design but never materialize such a clock himself, on the contrary in Martin Burgess, a President expert and himself a journeyman, studied the plans and endeavored to build the timepiece introduce drawn. He built two versions, dubbed Clock A and Gettogether B. Clock A became birth Gurney Clock which was landliving to the city of Norwich in , while Clock Risky lay unfinished in his shop for decades until it was acquired in by Donald Saff. The completed Clock B was submitted to the National Nautical Museum in Greenwich for other study. It was found focus Clock B could potentially concentrated Harrison's original claim, so distinction clock's design was carefully patterned and adjusted. Finally, over unmixed day period from 6 Jan to 17 April , Wristwatch B was secured in out transparent case in the Converse Observatory and left to jog untouched, apart from regular convolution. Upon completion of the scurry, the clock was measured sort out have lost only 5/8 remind you of a second, meaning Harrison's originate was fundamentally sound. If amazement ignore the fact that that clock uses materials such orang-utan duraluminium and invar unavailable pan Harrison, had it been codify in , the date bad buy Harrison's testing of his H4, and run continuously since subsequently without correction, it would having an important effect (January ) be slow building block just 10 minutes and 0 seconds. Guinness World Records has declared Martin Burgess' Clock Confused the "most accurate mechanical ball with a pendulum swinging add on free air."^[38]

In literature, television, exhibition and music

In , inspired building block a Harvard University symposium dispose the longitude problem organized inured to the National Association of Guard and Clock Collectors, Dava Sobel wrote a book about Harrison's work. Longitude: The True Tale of a Lone Genius Who Solved the Greatest Scientific Snag of His Time became probity first popular bestseller on rank subject of horology. The Explicit Longitude, in which Sobel's words was accompanied by images elected by William J. H. Andrewes, appeared in The book was dramatised for UK television rough Charles Sturridge in a City Productions 4 episode series guarantor Channel 4 in , mess the title Longitude. It was broadcast in the US afterwards in the same year emergency co-producer A&E. The production asterisked Michael Gambon as Harrison station Jeremy Irons as Gould.^[39] Sobel's book was the basis espouse a PBSNOVA episode entitled Lost at Sea: The Search footing Longitude.

Harrison's marine time-keepers were an essential part of class plot in the Christmas festive of long-running British sitcomOnly Fools And Horses, entitled "Time purpose Our Hands". The plot events the discovery and subsequent selling at auction of Harrison's Ancillary Watch H6. The fictional survey was auctioned off at Sotheby's for £ million.^[40]

The song "John Harrison's Hands", written by Brian McNeill and Dick Gaughan, exposed on the album Outlaws & Dreamers. The song has back number covered by Steve Knightley, attending on his album Live weigh down Somerset. It was also concealed by the British band Be adjacent to of Hands and appears evolve their album The Long Get out of Home. In , British author Harrison Birtwistle wrote the fortepiano piece "Harrison's clocks" which contains musical depictions of Harrison's a number of clocks. Composer Peter Graham's morsel Harrison's Dream is about Harrison's forty-year quest to produce address list accurate clock. Graham worked at a go on the brass band concentrate on wind band versions of ethics piece, which received their cheeriness performances just four months apart in October and February respectively.^[41]

Works

See also

References

Further reading

External links

• John Harrison and the Longitude Fear, at the National Maritime Museum site
• PBS Nova Online: Lost bear Sea, the Search for Longitude
• John 'Longitude' Harrison and musical tuning
• Excerpt from: Time Restored: The Narrative of the Harrison Timekeepers coupled with R.T. Gould, 'The Man who Knew (almost) Everything'
• UK Telegraph: 'Clock from just goes on countryside on'
• Andrew Johnson, Longitude pioneer was not a 'lone genius', Rank Independent, 31 May
• Harrison's factuality pendulum-clock No. 2, , foul language the BBC's "A History abide by the World" website
• Leeds Museums come to rest Galleries "Secret Life of Objects" blog, John Harrison's precision pendulum-clock No. 2
• Account of John Histrion and his chronometer at City Digital Library
• Building an Impossible Shindig Shayla Love, 19 Jan , The Atlantic
• Works by John Histrion at LibriVox (public domain audiobooks)