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Longitude Essays

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Commissioners of Longitude

The Longitude Act of 1714

The Longitude Act of 1714 [RGO 14/1:10] was intended to encourage both new and long-standing efforts at developing a better method of estimating longitude at sea. It is a mistaken modern idea that the Act also established a sitting body or 'Board of Longitude', whose members then failed in their duty to meet until at least 1737. In fact, the legislation simply named individual authorities who would be acceptable judges for funding and rewards. It gave these Commissioners of Longitude limited guidance. The term 'Commissioner' did not necessarily indicate membership in an institution during the early modern period. The Act itself did not employ any communal term such as 'Board', either. It also did not grant these officials any basic institutional resources like salaries and existing funds, a meeting place or specified contact, and staff such as a secretary.

A maximum of 23 original Commissioners of Longitude were specified either by name or by office and are listed at the bottom of this entry. (While the Act only mentions the Savilian professor of 'mathematics', it later became clear that both the Savilian professors of Geometry and Astronomy were being treated as acceptable Commissioners - resulting in a tally of 23. In reality, it was relatively common for one individual to hold two of the named positions at the same time, such as when the Astronomer Royal was also a professor. Some of the named individuals would also have been replaced or would have fallen from political power not long after the Act was passed, because Queen Anne died on 1 August and the Whigs came to power.) These Commissioners mainly included key figures from politics, the Navy, astronomy and mathematics. These were groups which were already seen as being key interests in the search for longitude.

Before the meetings: 1714-1737

A wide array of sources show that before the first known communal meeting of the Commissioners in 1737, the dynamics in the search for the longitude were much the same as they had been before. There was just a higher degree of interest and participation stemming from the new rewards. The same sorts of individuals and bodies were still being approached about the subject. The central longitude 'expert' remained the Astronomer Royal. After all, the Greenwich Observatory had originally been founded in 1675 by Charles II to produce astronomical data for finding the longitude at sea. Early projectors also approached authorities and individual Commissioners including the Royal Society and its President, representatives of the Admiralty and the Navy, the relevant professors at Oxford and Cambridge, and occasionally institutions such as the East India Company. Many would continue to do so even after the Commissioners began to meet.

Before 1737, many longitude-related activities took place despite the lack of communal meetings, including sea trials of proposals. The Astronomer Royal, at the least, participated in or commented on many of these. There was an early failed attempt at establishing further rewards as well. In 1720, the inventor and marine salvager Jacob Rowe tried to get legislation passed which would have allowed the Commissioners to give out rewards of up to £10,000 for the general improvement of navigation. During this time, longitude authorities and individual Commissioners most often directed projectors to the Astronomer Royal and/or to accumulate expert opinions and proof of success through publication and trials. A number specifically stated that the Commissioners should not be expected to meet to consider every longitude proposal, even though some projectors disagreed.

Isaac Newton said [Add 3972:37r] that since the Commissioners did not meet immediately in 1714 to determine what the Act meant and how it should be carried out - that they should not bother meeting at all until a proposal had accumulated proof of success [Add 3972:35v]. In 1733, the Commissioner Sir Thomas Hanmer similarly suggested that Jane Squire (the only openly female longitude projector) publish her ideas because he could not see the Commissioners ever judging first-round proposals. Instead, a proposal ‘must undergo the Scrutiny of all the great Professors of the Sciences of Astronomy and Navigation, and not only that but it must stand the Test of Practice’. [Jane Squire, A proposal to determine our longitude, 2nd ed. (London, 1743), pp. 26-36 Letters, Museum of the History of Science at Oxford.]

Early meetings: 1737-1760

The surviving minutes of group meetings show that small numbers of Commissioners gathered together at the Admiralty at least eight times from 1737 to 1757. It appears that it was the great public and institutional interest raised by John Harrison’s first marine timekeeper which prompted this move towards more communal discussion and decision-making. Harrison's work attracted a great deal of attention and support from a variety of individuals and institutions from the 1730s on. He also collaborated closely and agreeably with the Commissioners for at least two decades, attracting the bulk of their attention and funding before the 1760s.

The initial meeting of 30 June 1737 appears to have been more of a technicality in order to secure £500 of funding for Harrison at the urging of the Admiralty, than a significant change in the behaviour of the Commissioners. A number of the ensuing early meetings were mainly or wholly about granting the clockmaker another £500. At the meeting on 16 January 1742, the Commissioners also decided to extend their powers beyond the finding of the longitude for the first time. They agreed to give William Whiston £500 to assist in mapping the coasts of the Kingdom with his new astronomical and magnetic instruments. The meeting on 5 March 1748 is interesting because it is the first known to have been held for the communal presentation and consideration of proposals from projectors other than Harrison or the equally well-known Whiston.

In 1753, a new Parliamentary Act [RGO 14/1:15] expanded the number of Commissioners, since so many of the original members had died. The new officials included the Governors of the Royal Hospital for Seamen, the Judge of the High Court of the Admiralty, the Secretaries of the Treasury, the Secretary of the Admiralty, and the Comptroller of the Navy. On 6 March 1756, the Commissioners directed John Bradley to oversee sea trials of the lunar tables of Tobias Mayer, which would come to play a key role in the Commissioners' work on the lunar-distance method and in their production of related publications. However, John Harrison’s work seems to have been the main driving force behind the sporadic communal meetings which took place before the 1760s.

Before that decade, the Commissioners could not really be called a standing institution or Board at all. They met rarely and did not exhibit the characteristics of such a body, nor do they seem to have been perceived as such by the majority of contemporaries. The newspaper the London Evening Post reported the first known meeting in 1737 as if it were a friendly gathering of gentlemen rather than anything institutional: ‘the Right Hon. Arthur Onslow, Esq ; Speaker of the House of Commons, the Right Hon. the Lords Monson and Lovel, Sir John Norris, Sir Charles Wager, and several Persons of Distinction, view’d a curious Instrument for finding out the Longitude, made by Mr. Harrison’. The London newspapers don’t appear to have used the term ‘Board’ with reference to these officials until at least the early 1760s. The earliest example anywhere of a clear use of ‘the Board of Longitude’ in the sense of a standing body rather than as a one-time meeting may be in a letter of 1756.

Becoming an institution: the 1760s

From the 1760s on, the Commissioners increasingly institutionalised or bureaucratised themselves, and came to be known as 'the Board of Longitude'. As a result, most of the surviving documents in the Board archives are from this period and later. The Board began to meet at least annually and, in 1762, asked for travel compensation for the professors and Astronomer Royal and for a salary to hire a Secretary. As the decades passed, the officials regularly collaborated with other influential bodies including the Admiralty and Navy, the Greenwich Observatory, the Royal Society, and similar foreign institutions on a variety of activities. In addition to supporting Harrison’s work, encouraging the improvement of the lunar-distance method and occasionally considering other proposals, the Board expanded into the improvement of general navigation, science and technology.

This institutionalisation and expansion of powers appears to have occurred due to a combination of factors. These included the initial push from Harrison, later interest in additional methods including Mayer’s tables and even Christopher Irwin’s marine chair, recognition of other key issues in navigation and science, and occasional input from Parliament. The development of the Board may have also been influenced by the general bureaucratisation of Georgian government. Perhaps most importantly, though, it benefited from and was shaped by some very dynamic and committed individual Commissioners. These included Maskelyne, who was the Astronomer Royal from 1765 to 1811, and Joseph Banks, who was President of the Royal Society from 1778 to 1820.

Ironically, all of these developments also contributed to the highly publicised disagreements which arose between key Commissioners and John Harrison during the 1760s. Many of the officials were only recently arrived to their positions by merit of their "day jobs" rather than having been longtime collaborators of the clockmaker. This was also the first time that the Commissioners at large seem to have closely considered the underlying intent of the Act of 1714 - perhaps as a decision about rewarding Harrison drew ever closer. In addition, their bureaucratisation slowed and complicated events just as the clockmaker expected to finally get £20,000. In 1774, he successfully appealed to Parliament for a reward of £8750 on top of all of the sums which he had received in the past, in recognition of his efforts and advanced age. This led to the Longitude Act [RGO 14/1:37] of the same year, which repealed all former acts except those which appointed the Commissioners and those regarding the production of publications such as the Almanac and established rewards half the size of those of 1714.

The decades after John Harrison

The Harrison conflict of the 1760s tends to be the aspect of the history of the Board of Longitude that is most well-known to the modern public. It largely drove the two first decades of communal meetings of the Commissioners. However, more than two decades of individual activity preceded the clock maker's meeting in 1737, and more than a half century of Board activity followed! The archived records and official minutes which accumulated afterwards, and the later Longitude Acts, show how the Board was very productive post-Harrison.

Although no one ever won the reduced longitude awards of 1774, the Board continued to be involved in the improvement and testing of chronometers made by clockmakers such as Thomas Mudge (who was awarded £3000 in 1793), Thomas Earnshaw (who was awarded the same amount in 1805), and John Arnold (whose son was awarded £3000 that same year). The Commissioners also continued to contribute to other activities related to general navigation, science and technology including voyages like those of Captain James Cook.

The nineteenth century saw continued participation in diverse scientific and navigational activities as well but also significant changes in the makeup and behaviour of the Board. There were questions being raised by the early 1800s about the usefulness of the institution. Its membership under the influence of Joseph Banks was weighted far more towards the Royal Society than to the Admiralty, which did not even send any representatives to the meetings of 1813 to 1815. The quality of the Nautical Almanac after Maskelyne’s death in 1811 had also been criticised.

The longitude Act of 1818 [RGO 14/1:79r] sought to address some of these complaints and to emphasise the institution’s dedication to improving general science and navigation by repealing all previous Acts and reorganising the Board once more. The Board appears to have essentially became a scientific department for the Admiralty. The new Act appointed three salaried Resident Commissioners and three advisors who were Fellows of the Royal Society, as compared to the five unsalaried Fellows desired by Banks. It required four rather than three meetings a year, and dictated that the Board submit annual estimates of its expenditures with the Naval estimates.

It appointed the Foreign Secretary of the Royal Society as the Superintendent of the Nautical Almanac and as the Secretary to the Board. The Act further asserted the Commissioners’ ability to grant rewards for navigating the North West Passage, promising a reward of £20,000 for finding a passage and £5000 for reaching 100 degrees west or 89 degrees north. The smaller reward was granted two years later for the efforts of Lieutenant William Edward Perry and the crews of the Hecla and Griper .

Other relatively large rewards granted during the 1800s included the £1200 given to J. Mendoza y Rios for his improved longitude tables in 1814, and the £1000 given to Captain Edward Sabine for his pendulum experiments in 1826. The Commissioners further participated in activities such as the trigonometric determination of longitude between different observatories and cities, the funding of the Glass Committee alongside the Royal Society, and outfitting the new Royal Observatory at the Cape of Good Hope.

Parliament ultimately abolished the Board of Longitude in 1828. However, they replaced it with a Resident Committee of Scientific Advice to the Admiralty consisting of three scientific advisors: Thomas Young, Michael Faraday and Edward Sabine. The Board was, essentially, transmuted rather than abolished entirely. The ambitions and interests of key Commissioners and the needs of navigation, science and technology had led to its constant definition and redefinition over 114 years. It became not just the bureaucratic overseer of some large rewards but an important authority, publisher and funding body across European science and navigation. It was an intersection of many dynamic and influential spheres. In its origins, development and final transformation, it was unusual and perhaps even unique amongst Georgian government institutions.

The 1714 Commissioners:

By office:

  • The Lord High Admiral of Great Britain, as the First Commissioner of the Admiralty
  • The Speaker of the Honourable House of Commons
  • The First Commissioner of the Navy
  • The First Commissioner of Trade
  • The Admirals of the Red, White, and Blue Squadrons
  • The Master of the Trinity House
  • The President of the Royal Society
  • The Royal Astronomer of Greenwich
  • The Savilian, Lucasian, and Plumian Professors of Math in Oxford and Cambridge

By name:

  • The Right Honourable Thomas Earl of Pembroke and Montgomery
  • Philip Lord Bishop of Hereford
  • George Lord Bishop of Bristol
  • Thomas Lord Trevor
  • Sir Thomas Hanmer Baronet, Speaker of the Honourable House of Commons
  • Francis Robarts, Esquire
  • James Stanhope, Esquire
  • William Clayton, Esquire
  • William Lowndes, Esquire

Alexi Baker
History and Philosophy of Science
University of Cambridge