John Harrison (1693-1776) and the Heroics of Longitude

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John Harrison (1693-1776) and the Heroics of Longitude DOI 10.6094/helden.heroes.heros./2014/02/09 Ulrike Zimmermann 119 John Harrison (1693-1776) and the Heroics of Longitude 1. A Symposium and a Rediscovery bestseller, and Dava Sobel embarked on a car­ eer as a well­known and respected author of 2 When American journalist Dava Sobel attended popular science books. the Longitude Symposium of Harvard Univer­ Dava Sobel’s first subject already was his­ sity at Cambridge, Massachusetts, in November tory, albeit part of an unaccountably hidden or 1993, she did not expect anything decisive to at least underrated history. John Harrison was a come out of either the conference or her attend­ carpenter and self­taught clockmaker, who was ance. “500 people from seventeen countries” born in Yorkshire and spent his early life in Bar­ came together to hold “a conference about the row­upon­Humber, North Lincolnshire. He would history of finding longitude at sea,” W. H. An­ prob ably have spent his life in obscur ity had he drewes, curator of the scientific instruments col­ not solved one of the major techno logical prob­ lec tion at Harvard, notes in his introduction to lems of his time, the problem of how to determine the conference proceedings (Andrewes, Intro­ a ship’s east­west position, its longitude, at sea. duction 1). Despite the sizable number of par­ Harrison has a firm place in the his tory of navi­ ticipants, the Longitude Symposium was at first gation, and would have been known amongs t sight a convention of specialists sharing their horologists, clock and watch makers, and nava l knowledge and discussing finer points of their historians. The general pub lic, how ever, be­ academic work, not a convention to arouse grea t came acquainted with John Harrison and his public interest. This particular symposium, how­ major achievements through the publication of ever, triggered a series of cultural products and Sobel’s Longitude. In its wake came more cul­ events which disseminated specialist knowledge tural products dealing with John Harrison’s life to many people who had not necessarily been and work: Longitude was adapted as a TV mini interested in the history of longitude before. Out series and broadcast in 2000. The National Mari­ of the whole process emerged a new tale of her­ time Mu seum in London produced a documen­ oism with an unlikely protagonist who is anything tary on Harrison and his timekeepers [which are but conventionally heroic, and who had been housed in the Royal Observatory] in 2001 and is dead for more than 200 years at the time of the commemorating the tercentenary of the estab­ Longitude Symposium: John Harrison [1693­ lishment of the Board of Longitude with a series 1776], the inventor of the first reliable marine of exhibitions: Ships, Clocks & Stars: The Ques t timekeeper. for Longitude [July 2014­January 2015] and Dava Sobel had been asked to write an art­ Longitude Punk’d [April 2014­January 2015]. In icle on the Longitude Symposium for the Harvard 2006, John Harrison received a public memor­ Magazine. Although it became the cover story, it ial in Westminster Abbey, which was unveiled by did not receive much attention from its readers.1 Princ e Philip. As it turns out, Harrison is enjoy­ But then Sobel was approached by the owner ing a stellar career cen turies after his death: He of a publishing house, George Gibson of Walker developed from a specialist with an excellent Books, who suggested she should turn her sub­ reputation and a place in the history of science, ject into a full­length book – which she duly did. whose contribution to modern­day navi gation The rest is, as the saying goes, history: Sobel’s was spectacular, but who was known only to a first book Longitude: The True Story of a Lone scientific community, to a public, even popular th Genius Who Solved the Greatest Scientific Prob­ character in the late 20 century. In the BBC pro­ lem of His Time came out in 1995 to become a gramme 100 Greatest Britons of 2002, Harrison came out 39th (cf. The Top 100 Great Britons). helden. heroes. héros. Ulrike Zimmermann 120 This case study will attempt to shed light on how solving the longitude problem, he made inven­ an unassuming eighteenth­century craftsman tions which had a lasting impact on clockmaking: has in the recent past become the central fig­ the gridiron pendulum, welded together out of ure of a story of heroism, which unfolded across different metals in order to compensate for tem­ a variety of media. It will be suggested that the perature changes; the bi­metallic strip, used in attribution of heroic characteristics made John clocks to similar effect, and the grasshopper es­ Harrison more easily accessible and also more capement, an escapement with very low friction. attractive to a wider audience. His heroic feat was This list points to the fact that Harrison’s work finding the solution to a highly specific prob lem has specialist appeal at best, but not necessar­ of technology, which turned out to revo lutionise ily heroic qualities. Despite his good results and navigation and largely contributed to the creation enormous skills, it took Harrison four decades to of the naval power Britain has been for centuries. convince the scientific community of the quality John Harrison’s life and work are not necessarily and reliability of his clocks.3 the stuff heroes are made of, but on closer scru­ In 1714, the British Parliament had, by pass­ tiny contain elements which have the potential ing the so­called Longitude Act, established for a remarkable narrative. The his torical facts a Board of Longitude. A prize of £20,000 was known about him speak of an interesting person­ offered to anybody who would invent a practic­ ality. Arguably, giving John Harrison an elevated, able method of establishing longitude aboard potentially heroic status has elements of narra­ ship. The hopeless inaccuracy of current lon­ tive emplotment in the sens e used by Hayden gitude determination had by this time, with the White. It is suggested that with out Dava Sobel’s expansion of the British Empire and the naval initial narrative approach, which earlier accounts requirements of war as well as trade, become of Harrison lacked, his life and achievements the bane of the naval community. In fact, the would not have gained such a strong appeal for Longitude Prize was largely the consequence of so many. As Dava Sobel may not have been the the naval disaster off the Isles of Scilly in 1707, first to discover this potential, but was certainly when an estimated 2000 men drowned as Ad­ the first to exploit it [in both the positive and the miral Sir Cloudesley Shovell4 and his fleet were negative sense of the word], her book will be the returning from action in the War of the Spanish focus of this analysis, including a close reading Succes sion. Four ships from Shovell’s fleet ran of some of Sobel’s textual strat egies. The John aground on rocks off the Isles of Scilly. Due to Harrison phenomenon crosses a variety of text­ bad weath er and a miscalculation of the position ual and visual media, moving into film and exhib­ of the fleet, and despite all qualified, state­of­the­ itions, which will be taken into account as well. art attempts at reckoning [Shovell had sensed the danger and consulted all of his navigators] the sailors had not realised how close they were to the Isle of Scilly, but thought they were west 2. John Harrison, Clockmaker of the Ile d’Oussant [Brittany], which would have – A Brief Overview meant a safe passage to the harbour of Ports­ mouth. Losing so many men and ships practical­ John Harrison’s invention of the marine chro­ ly at Britain’s doorstep, in one of the worst naval nometer with which it became possible to deter­ disasters in British history, apparently had polit­ mine a ship’s longitude while at sea with a de­ icians finally springing into action. Andrew King gree of certainty, revolutionised navigation. As describes the dimensions of the problem and the the son of a carpenter, Harrison’s initial material solution as follows: of choice was wood, and in fact, his first clocks – hardly conceivable today – were wooden clocks. The immense awards offered under the As there was no community of clockmakers in Act are testimony to the urgency of the Barrow­upon­Humber, it is unknown how Harri­ problem. […] Under the terms of the Act, son came into contact with this particular craft. in order to obtain the full £20,000 it was re­ quired that the method, whatever it might He was certainly a well­trained carpenter, but a be, must determine longitude to within a self­taught clockmaker. Initially, John Harrison distance of 30 miles during a voyage from worked on his own. He must have been an ex­ England to the West Indies. To achieve tremely patient craftsman with touches of the this, a mechanical timekeeper would have DIY tinkerer, who over his lifetime produced, to be accurate to within a total of just two amongst other clocks, different marine chronom­ minutes during the proposed six­week eters [now specified as H1 to H5], each more trial. Every clockmaker knew that this was advanced than its predecessors. On his way to impossible with the technology then avail­ able. (King 168) helden. heroes. héros. John Harrison and the Heroics of Longitude It is unknown how and when John Harrison trappings: It announces a true story, which has 121 heard about the Longitude Prize.
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