Joseph Jérôme Lefrançois de Lalande was the editor of the French Connaissance des Temps and a friend and collaborator of Nevil Maskelyne and other English longitude actors. Recently I noticed that in Lalande’s diary from his 1763 visit to England – during which he viewed the marine timekeepers of John Harrison – he recounted an unusual comment made about one of his colleagues.

On Easter Saturday 1763, Lalande recorded that the Astronomer Royal Nathaniel Bliss said ‘that Mr Lemonnier attached the wire to his quadrant with wax from his ears, that he went to Oxford with his sword broken, and that his observations agree less well with those of Mr Bevis than those of Caille.’ Pierre Charles Lemonnier or Le Monnier was a talented French astronomer 17 years Lalande’s senior who had a penchant for British instruments and astronomical methods and was a member of the Royal Society and the French Academy of Sciences. His quadrant was made by Jonathan Sisson, a well-known London instrument maker whose son Jeremiah made Christopher Irwin’s marine chair in the late 1750s and unsuccessfully sought a reward from the Board of Longitude in the late 1760s.

Are the statements attributed to Bliss a neutral record of Lemonnier’s characteristics and of his approach to using instruments – with the earwax method just being another of the ways in which individuals worked out how to use or adapt or repair their instruments? Or was the entire statement intended as a slam against the older astronomer’s abilities but also his gentility? A sword was an important symbol for an early modern ‘gentleman’ – even if by 1727 César de Saussure said that the label was ‘usually given to any well-dressed person wearing a sword’ in England – and Lemonnier’s was said to be broken.

Although Lemonnier had helped to launch Lalande’s astronomical career, the two astronomers fell out for years – either over the former’s temper or over the latter’s indiscreet manner of correcting his colleague’s errors, according to different sources. It would be fascinating to know – perhaps someone out there can help? – whether this was just another round in their disagreement or whether Lemonnier really did incorporate his earwax into his astronomy.

Fig. 40, 'Tidens naturlære', Poul la Cour, 1903 - Wikimedia.

I have recently been working on a small display at the Royal Observatory (opening next month) called Measuring the Universe. Despite being small-scale the topic is – in every sense – vast. The Observatory’s Public Astronomer, Marek Kukula, and I are trying to cover the history of measurements of the scale of the solar system, the distance to the nearest stars, the space between galaxies and to the Cosmic Microwave Background. This takes us from the Earth to the edge of the known universe, and from Greeks to researchers today.

I have been focusing on the story of measuring the Astronomical Unit, that is the distance between the Earth and the Sun, and mainly on the use of the rare astronomical phenomenon of the transit of Venus to measure solar parallax. In 1761, 1769, 1874 and 1882 there were a huge number of observations made, across the world, motivated by the hope of establishing a scale for the workings of the Newtonian solar system, thereby improving astronomical theory and predictions, but also by a range of practical, geographical, national and imperial interests. A useful list of historic transit observations can be found here.

There are three good reasons for turning over half of the exhibition to this story: 1) there is a transit of Venus happening this June, probably the last opportunity to see it in any of our lifetimes 2) the Royal Observatory and its staff were much involved in the effort of organising expeditions, observing transits and reducing the data to produce results and 3) transit observations required overseas expeditions, as measuring solar parallax required observations from different latitudes, which involved maritime navigation, exploration and a host of themes of interest to the ROG, the NMM and me, as curator and a member of the Longitude project team.

Distilling down a story that includes Edmond Halley, Nevil Maskelyne, James Cook, George Airy and a host of the ROG’s assistants – to indicate just a few on the British side – has been challenging, to say the least! The main mission is to convey an idea of the method, the amount of organisation and effort required, the international nature of the enterprise, and the wide interest that it evoked, well beyond the scientific world. With the international story, I have tried to show that the co-operation that took place with regard to promoting expeditions and collating results was probably less significant than the national rivalries, the dangers of travelling during the war, and the selection of locations for observing that related directly to imperial and trading interests.

There are so many fascinating stories to which we cannot do justice in the available space. I am hoping to include one of the best – the sad tale of Guillaume Le Gentil – but it is impossible to explore the background fully. This includes the Seven Years’ War and, specifically, the French/British rivalry in the Indian Ocean and desire for access to India and trade routes. This military and geopolitical history does not always get enough attention in the story of longitude. Not only did overseas trade and competition provide a spur to finding a solution, the process of finding one was sometimes impeded by war (for example, when Harrison’s first timekeeper was to be tested, they were unable initially to make the journey to the West Indies required by the 1714 Act), and sometimes , of course, contributed to the extension of imperial interests – as in the voyages of Cook and those who followed.

Because the history of transit observations is wound up with that of Cook (his first voyage was a transit expedition, as well as a testing ground for the new Nautical Almanac and a mission to locate and claim the southern continent), the current interest surrounding the 2012 transit has encouraged some to think about longitude and navigation. I spotted, on The Transit of Venus site blog, a post by Nick Lomb on How Cook navigated to Tahiti. This includes a discussion of the extent to which Cook knew “his position at all times” as a result of having access to the first edition of the Nautical Almanac. This mainly focuses on the point that lunar distances won’t work in cloudy skies, but misses the fact that Cook and Charles Green (the official astronomer, and former ROG assistant) ran out of Nautical Almanac predictions over the course of the voyage and that the length of time it took to calculate position by lunar distance usually meant that the navigator would only know where he had been rather than where he currently was. Precise position for charting and, especially, for locating observers of the transit of Venus would have been carried out by observing transits of Jupiter’s satellites rather than, or as well as, lunar distances.

Readers of this blog might also be interested in the current voyage of the replica of Cook’s ship, HMB Endeavour, owned by the Australian National Maritime Museum. The crew is currently cirumnavigating Australia and will stop at Lord Howe Island (named after Richard Howe, a regular attendee of Board of Longitude meetings in the 1760s, as Treasurer of the Navy, and in the 1780s, as First Lord of the Admiralty) to observe the transit of Venus. Those on board, either for the whole circumnavigation or for the transit of Venus leg, will be learning and using 18th-century sailing and navigation techniques. I am assuming that they have 21st-century backup!

I find it striking how our understanding of the early Board of Longitude is defined as much by the absence of evidence as by its presence. For example, there is the perennial question: Was the gathering of 30 June 1737 truly the first official communal meeting of the Commissioners to have ever taken place? There are reasons to question whether or not this is true. Sources including the private papers of Nevil Maskelyne show that other formal (and informal) meetings of the Commissioners took place besides those entered into the ‘official’ minute books – although so far none are known to have occurred before 1737.

The existing records of the activities of the Board may have also been shaped and reshaped by the ways in which they were produced and compiled. For example, the minutes were often based upon the notes or later summaries of one meeting attendee – in many cases Maskelyne until his death in 1811. They were also later compiled and in some cases recopied at different times and for different reasons, in the process of which some errors were made. The selection and presentation of the extant Board minutes may have been further shaped by the later Astronomer Royal George Airy, who collected, reorganized and had them bound in 1858.

Eoin found a lovely quote from Airy regarding the end of this enterprise: ‘The Papers of the Board of Longitude are now finally stitched into books. They will probably form one of the most curious collections of the results of scientific enterprise, both normal and abnormal, which exists.’ You can see in the photo below a note written by Airy which is bound alongside the earliest surviving minutes in volume RGO 14/5 (now at Cambridge). How much did Airy’s rearranging and labeling of such documents (for example, as ‘impractical’ schemes) affect historians’ views of the Board? Could Airy or an earlier archivist also have disposed of some of the records which he deemed unimportant to the ‘official’ history of that body, for example from before the ascendance of John Harrison?

Some documents which are vital to understanding the history of the Act of 1714 and of the ‘Board’ have definitely fallen through the cracks. For example, there appears to be no extant copy of the famous petition to Parliament of 25 May 1714 from ‘several Captains of her Majesty’s Ships, Merchants of London, and Commanders of Merchant-men’ which is thought to have truly started the ball rolling towards the establishment of a longitude reward. Without knowing more details about its contents than have survived in the records of the House, there is so much which we can’t discern.

Was the petition truly an unprompted outpouring of concern from the nation’s maritime interests, or was it directly instigated or perhaps even scripted by William Whiston and Humphry Ditton? Whiston and Ditton had started lobbying for a longitude reward by 1713, and there are certainly similarities between the summarized contents of the petition and the contents of these two projectors’ publications. And could the contents of the petition have directly informed a draught Parliamentary bill now in the United States, which would have levied a duty on all shipping in order to provide British vessels with the means of finding the longitude?

If we go back further, even the original events of the early history of ‘the Board’ were marked by an absence of information. As I explain at greater length in an upcoming article, the Act of 1714 did not actually establish a standing body or ‘Board’ – but some percentage of contemporaries did not know this. We have not yet come across evidence that the detailed contents of the Act of 1714 were ever widely publicized, for example through the spread of handbills. Jane Squire, the only female longitude projector known to date, had to ask the Attorney General to read the text of the Act to her in 1731. As a result, it is not just longitude projectors but also the Commissioners themselves who expressed some confusion during the ensuing decades about their legislated nature and about the intended conduct of the longitude contest.

When eight Commissioners met together at the Admiralty on 30 June 1737, it seems to have received limited coverage, which did not necessarily mention the Act of 1714. For example, the London Evening Post simply reported that these ‘Persons of Distinction, view’d a curious Instrument for finding out the Longitude, made by Mr. Harrison’. When Squire wrote to Sir Charles Wager four years later to continue her decade-long campaign to have the Commissioners consider her proposal, she was not aware that the officials had ever met communally.

Photo credits: Cambridge University Library.

It is clear that another component of the Harrisons’ suspicions towards Nevil Maskelyne was their long-held conviction that he was actually a competitor for the longitude reward that they thought was rightfully theirs. We cannot be sure whether or not Nevil was hoping to obtain one of the rewards for his work on the lunar-distance method before he became the Astronomer Royal, which automatically made him a Commissioner of the Longitude, in 1765. It was possible, given his interests and abilities as a young man, and was in no way morally questionable.

The Harrisons do not seem to have objected at first to his being selected as an astronomical observer for the second sea trial of H4, which took place before he obtained the position at Greenwich. They would have already been aware that he was a proponent of the lunar-distance method and had also been directed by the Commissioners of the Longitude to make trials and observations relevant to the method during his voyage to Barbados. However, William Harrison recorded that he heard rumours once he reached the island that the astronomer was a true fellow competitor for the longitude reward and apparently rushed to confront him and to accuse him of being an improper choice to participate in the trial. We do not know what Maskelyne said in response, but the accusation apparently distressed him and led to his alternating observations with his companion under the watchful eyes of multiple witnesses.

Quill wrote of this event that, ‘The objections raised by William Harrison reveal the spirit of suspicion and antagonism against Maskelyne that seems to have been continually in his mind, an attitude which was shared by his father, and which was to persist to the end.’ There is also no evidence so far that once the maligned observer became Astronomer Royal and thus a Commissioner that he tried to obtain a reward for his efforts, which to modern eyes would have definitely seemed a ‘conflict of interest’. As Katy has shown during her research on the Barrington papers, it is possible that the Commissioners of the Longitude considered including wording in the Parliamentary Act of 1765 which would have prevented any serving Commissioner from winning the reward – perhaps to avoid accusations of this nature.

My pointing out these potential contributing factors to the later conflicts between the Commissioners of Longitude and the Harrisons, which will be explored at greater length during our research, is not intended to come down on one ‘side’ of the issue or the other. Doubtless no party in this episode could be called a perfect angel. It is quite likely that the clockmakers believed the accusations that they levied against Maskelyne and the other Commissioners in public, and it is understandable that they grew increasingly frustrated as years passed without their gaining the reward they were convinced should belong to John. However, there is so far no evidence for, and it in fact seems highly unlikely, that the Commissions and particularly the Astronomer Royal were unduly critical of the sole use of timekeepers for finding the longitude at sea or actively plotted against the Harrisons. This interpretation was far less widely held when the events actually took place than it is now, thanks to selective modern readings of the evidence.

This popular modern interpretation encourages a false understanding of not only the nature and activities of the Commissioners of Longitude, but also of the development of mathematics, astronomy and navigation in general in early modern Britain and Europe. It especially obscures the myriad contributions of Nevil Maskelyne to those areas by hiding the real individual, who was Astronomer Royal and a key force amongst the Commissioners and the Fellows of the Royal Society for decades, behind the unrecognizable mask of a pantomime villain. He and John Harrison should both be recognized for their intelligence and innovation, and for the steps forward that they prompted in the art of early modern navigation.

(Really the lunar-distance method deserves to be rehabilitated in the popular opinion as well. Chronometers did not make a clearly stellar showing in sea trials until the 1770s, at which point only a handful of the instruments even existed in Britain. They were not cheap enough to be widely used until the 1800s, and some scholars have suggested that their true promise was not realized until the advent of steam-powered sailing. In the meantime, the pursuit of an accelerated lunar-distance method led to other improvements in astronomy and navigation, the establishment of the Nautical Almanac which is still being published, and the development of the basic sextant design that is still in use today – as seen here. Even after chronometers came into wider use aboard ships, astronomical observations continued to be necessary as well for measuring the local time with which the chronometer’s GMT would be compared and, in the earlier days, for checking on the accuracy of the timekeeper.)

At any rate, no matter how many factors contributed to the initial deep divide between the Harrisons and the Commissioners of the Longitude, their working relationship was pretty much irrevocably broken by the 1760s and 1770s and only proceeded in stops and starts. The Harrisons were convinced by then that the Commissioners’ secret enmity towards them had come to a head, and ultimately that they had no hope of inducing the officials to see things their way and to give them the full reward that they deserved.
 
Meanwhile, the Commissioners no doubt watched with horror as the Harrisons and their supporters published lengthy public accusations against them and particularly Maskelyne in pamphlets and in periodicals. Their dissatisfaction sometimes spilled over into board meetings as well, as when John responded to their requirements for a ‘discovery’ of his watch designs in 1765 by exclaiming ‘That he never would consent to it, so long as he had a drop of English Blood in his Body’ and leaving the room ‘abruptly’.

Historical events like these are always messy things to deal with, and especially those that encompass a period of more than a century, as we are examining. They were far from tidy and clear-cut when they occurred, and often to understand them, we have to clear away the cobwebs of later interpretations, moral judgements and narrative restructurings. These interpretations often have more to do with the times in which they were developed than with the historical periods that they purportedly describe!

Picture credits: All images © Wikimedia Commons.

The Harrisons and the bulk of the Commissioners of Longitude may have ended up conflicting so much by the 1760s and 1770s because they held a number of different social, legal and economic viewpoints. Some of these can be attributed to the general confusion that existed in Georgian Britain about ‘state’ and ‘private’ ownership and rights when it came to ‘scientific’ and intellectual works that had received state sponsorship. For example, the Commissioners and the Royal Society engaged in social and legal battle with the family of James Bradley (seen below) and later with the Oxford University Press for 36 years after the death of that Astronomer Royal, over the ownership and printing of the astronomical observations that Bradley had made at Greenwich. The officials believed that the state owned the papers, since the astronomer was employed by and made the observations at an observatory founded by King Charles II in 1675 and funded (albeit somewhat poorly) by the Board of Ordnance. Bradley’s relatives, on the other hand, believed that he and thus they owned the papers and at least deserved a sizeable monetary reward if they turned them over to the Royal Society.

The Commissioners essentially claimed a degree of ownership over Harrison’s timekeepers as well, because they had funded their development and testing and thought that the clockmaker was required to prove their use to the nation before getting the ultimate reward. On the other hand, the clockmaker believed them entirely his property – as most early modern craftsmen and inventors probably would have — and sufficient in their own right to win the reward. The relationships between issues and bodies of state and more ‘commercial’ concerns were fluid during this period, and the barriers between them highly permeable or at times nonexistent. This could encourage advancements in areas such as technology, but could also prove problematic in the absence of clearly established precedents for reconciling the two interests.

I suspect that the Harrisons and the Commissioners had broadly different perspectives in other ways as well, which may have further aggravated the misunderstandings and later ill will between them. The clockmakers clearly dedicated much of their lives year-round to the development of, and the seeking of recognition and reward for, John’s marine timekeepers. There were of course a number of Commissioners of Longitude who served in that position for years, and Maskelyne in particular dedicated much of his time to activities related to his being a Commissioner. However, the Commissioners at large would have still had more of a part-time and institutional view of events than did the clockmakers.

After the initial Act of 1714, which also named some specific individuals, officials and professors became Commissioners by virtue of their other ‘full-time’ positions. From 1737 onwards, boards of longitude sometimes failed to meet at all in a year, and were later only required to meet on a few separate days unless it was judged necessary to schedule more meetings. Maskelyne was an unusual case, and many of the Commissioners would not have done much or perhaps even thought much about issues related to the board in between meetings. The Harrisons would have naturally approached board meetings, especially as the decades passed, with a more pressing concern and with a greater sense of the passage of time (and the aging of John) than would have most of the officials with whom they dealt. The former wanted immediate action, whereas the Commissioners represented a governmental body and sought to apply a legal and bureaucratic framework to their decisions and actions. The officials were also involved in considering and sometimes encouraging more than just one proposal for finding the longitude at a time, and soon became involved in other activities related to navigation such as producing and encouraging related publications.

Perhaps the Harrisons were further encouraged in thinking that the bulk of the Commissioners were plotting against them simply because of the way in which early modern British society worked. At all socio-economic levels and in all trades and pursuits, interpersonal relationships and networking played an even greater role than we tend to think they do today. For example, my previous research on ‘scientific’ instrument makers and sellers in early modern London showed how common it was for almost all aspects of a trade member’s business – from simply finding a person to transport an item of stock, to the momentous establishment of a first shop or the choosing of a partner or apprentice — to be guided by the wide variety of people whom he knew. These often included not only fellow instrument makers and livery company members but also members of interrelated trades and interest groups, blood and marital relatives, religious friends, neighbours, and so on. In the case of trade members who were London-born, these contacts were often spread across the provinces or abroad as well as in the metropolis. 

In this sort of milieu, it was the norm rather than the mark of an invidious ‘old boy society’ for the Commissioners to have their activities, such as the choice of observers for the different sea trials, strongly influenced by interpersonal connections and greased by social and well as ‘professional’ interactions. The world was a smaller place at that time, and concepts of relationships and ‘professionalism’ rather different. John Harrison of course benefitted from some similar ties over the course of his career, with established individuals including well-known instrument makers, Commissioners and public figures such as James Short, George Graham, Edmond Halley, John Cust, John Bevis, and Taylor White of the Foundlings Hospital encouraging him and representing his case to the public and to the government.

However, one can see how the Harrisons – increasingly paranoid and defensive as the years passed, although perhaps for some valid reasons – might have perceived such interactions and interconnections betwixt many of the Commissioners and associated individuals as ominous towards their cause. After a board meeting in 1764, William Harrison wrote to his father-in-law that they were newly optimistic about obtaining the longitude reward, in part because of the recent death of the Astronomer Royal Nathaniel Bliss, who had been one of the many individuals also interested in the lunar-distance method: ‘They were all as agreeable as could be, Parsons [i.e. professors] and all, as they have now lost their ringleader.’ This problem of perception may have applied even more so to the case of Nevil Maskelyne, who was apparently quite amiable and maintained many friends across the learned and intellectual spheres – even those with whom he conflicted on a professional level, such as Joseph Banks, the divisive president of the Royal Society.

To read about additional reasons why the Harrisons may have considered Nevil Maskelyne their arch nemesis, see the final part of ‘Rehabilitating Nevil Maskelyne’ tomorrow: ‘The Harrisons’ issues with Maskelyne, and Conclusions’.

Picture credits: Portrait of James Bradley, Wikimedia Commons.

Another element of the accusation that Maskelyne and the Commissioners of Longitude were wrong-headed in their treatment of John Harrison, is the idea that they were short-sighted to continue to consider the lunar-distance method as well, and that they were over-invested in it due to self-interest. Today many people have the impression that the lunar-distance method — and earlier proposed methods of finding the longitude at sea that were based upon magnetic variation or observations of the moons of Jupiter — was as laughable as the so-called ‘powder of sympathy’. If that were true, then surely Maskelyne and the other Commissioners were stodgy / unintelligent / prejudiced / etc. for not having seen from the beginning that timekeepers were the way to go!

However, many intelligent people including Isaac Newton were not sure that clockmakers could make timekeepers hardy, affordable and regular-running enough to fully shoulder the burden of finding longitude at sea – at the time of the Act of 1714 but also well into the second half of the eighteenth century. Before Harrison, the technology just wasn’t there, and seagoing timekeepers were not perceived in terms of precision and reliability. The longitude proposals which involved astronomical observations, or indeed compasses, had a somewhat greater affinity with centuries-old navigational practice than did precision timekeepers as well (although mariners sometimes used sand-filled hourglasses). As Katy mentioned in her last post, when Newton testified to a Committee of the House of Commons in 1714 about four potential longitude solutions, he pointed out that there were key problems with all of them (timekeepers, lunar-distance, observations of the eclipses of Jupiter’s moons, and a much-publicized and sometimes parodied plan by Humphry Ditton and William Whiston involving moored ships launching mortars into the air at regular intervals along established trade routes).

As the decades passed, innovations in astronomy and technology and relatively successful sea trials made it seem more likely that the lunar-distance method and timekeepers could both provide a solution. Many people, including Maskelyne, thought that it might be most effective to employ the two together, if only reliable enough timekeepers could be produced. (The astronomer pointed out that in theory, errors in lunar-distance observations and calculations made aboard ship would not carry over from one day to another, whereas any unpredictability in the going of marine timekeepers would only become magnified as the days passed.) The astronomical data and computations upon which the abbreviated version of the lunar-distance method was based, still needed to be precise enough and widely available for years in advance to be of widespread use – which increasingly came to pass from about the 1760s onwards as Maskelyne published his Nautical Almanacs and associated Tables. However, weather could still pose a problem to observations, calculations still took some time to complete, and older mariners were sometimes reluctant to learn the skills necessary to use the lunar-distance method.

In order to be useful for finding the longitude at sea, timekeepers need to have a very predictable going rate (i.e. the amount of time gained or lost each day) and to be able to stand up to changing conditions aboard ship but also, in the end, to be produced widely and far less expensively than could Harrison’s inventions. At first, the Harrisons and the Commissioners differed over whether John’s timekeepers had been put to acceptably rigorous and defined testing with respect to the first set of requirements once they were trialled at sea and at observatories on land. Then in the 1760s and 1770s, the Commissioners were particularly concerned about whether or not the timekeepers could be reproduced for widespread use, since otherwise they would be of little use to navigation and trade as a whole.

The Commissioners periodically encouraged both Harrison’s timekeepers and the lunar-distance method over the years – but the former actually received the first known award of money from the Commissioners and accounted for most of its expenditures until 1763, which challenges the clockmakers’ beliefs that the officials were prejudiced against them or timekeepers in general. (Professor Eric G. Forbes, who was of the opinion that the German astronomer Tobias Mayer (left) could equally be called the ‘discoverer’ of longitude at sea, came to the same conclusion because the Commissioners approached Mayer’s improved tables for the lunar-distance method just as critically as they did Harrison’s claims.) By the time Parliament awarded £8750 to John in 1773, he had already received grants of money from them totalling more than £13,000. When he asked for more funding in 1746, he told the Commissioners that their periodic financial support of him was much appreciated and vital, since ‘the Difficulty in the Contrivance & the Nicety in the execution of many parts of these new designs have so entirely ingrossed his time & thoughts for many years past as to render him quite incapable of following any gainfull employment for the support of himself & family’.

To find out how a number of ‘cultural’ differences may have contributed to the Harrisons’ conviction that Maskelyne and the Commissioners were plotting against them, see Part Three of ‘Rehabilitating Nevil Maskelyne’ tomorrow.

Today is the bicentennial of the death of Nevil Maskelyne (6 October 1732 – 9 February 1811), who was much admired in his own time but has been unfairly reduced in recent years to the arch villain in the tale of John Harrison‘s invention of the marine chronometer. As I’ll be discussing in this four-part series of posts, the bulk and perhaps the whole of these accusations against Maskelyne and his fellow Commissioners of Longitude are almost certainly untrue. They also obscure the long and storied career of a champion of, and innovator in, subjects including navigation, astronomy, cartography, geodesy and institutional reform.

Part One: In praise of Nevil Maskelyne, and reassessing the Harrisons’ accusations
Part Two: Why lunar-distance?
Part Three: ‘Cultural’ differences and the Commissioners’ conflict with the Harrisons
Part Four: The Harrisons’ issues with Maskelyne, and Conclusions

Early in his career, Maskelyne was central to the reorganization of the Royal Observatory at Greenwich, where previously Astronomers Royal had refused to make the results of their observations public and sometimes let the buildings and instruments fall into disrepair. During his own 46-year tenure as Astronomer Royal and thus as a Commissioner, Nevil was the driving force behind navigational and astronomical innovations including the foundation and advance publication of the Nautical Almanac. A number of his Astronomical Assistants at Greenwich went on to participate in geodetic and astronomical expeditions in their own right due to his teaching and influence, something which never happened under the previous Astronomers Royal. The astronomer and Joseph Banks were the longest serving and most influential of the later Commissioners as well, and the former was given the responsibility for an unbelievable amount of the officials’ activities, judgements and practical arrangements.

Maskelyne was also deeply involved in the activities of the Royal Society, for example publishing an unusually high number of articles in its Philosophical Transactions (more than 50) and helping it and the Commissioners to organize famous voyages of exploration and early science including those made by James Cook (left). This is only a ‘taster’, really, of the many things which the astronomer accomplished during his jam-packed and relatively long life. He was involved with a wider variety of activities than I have time to mention here and participated in expansive global networks of colleagues and friends.

Today I will explain some of the fallacies behind the modern view of Nevil Maskelyne and of the Commissioners of Longitude in general as corrupt, prejudiced and/or unintelligent and uninsightful with regards to their treatment of the Harrisons. This view, which as been put forth by some modern authors including Dava Sobel, is not accurate but has unfortunately come to define the astronomer and his colleagues in the public consciousness. There is so far no evidence that it was true beyond the Harrisons’ later accusations. There are a number of factors that are far more likely to have influenced the decisions and actions of  Maskelyne and the other Commissioners, and to have contributed to the discord that existed between they and the clockmakers by the 1760s and 1770s (as we’ve already discussed a bit in comments on other posts).

It’s certainly possible that some well-born or well-educated Commissioners did privately hold snobbish feelings towards the ‘rough and uneducated provincial genius’ John Harrison, as has sometimes been suggested to great dramatic effect. However, there is so far no evidence that this greatly influenced the treatment of Harrison and his inventions, and especially in the case of Nevil Maskelyne. The perception that it did often stems from far more attention being paid to the Harrisons’ emotional and verbose public statements and accusations than to the whole of the surviving records related to these events.

In fact, the majority of the scholars who have examined the eighteenth-century search for the longitude in-depth believe that the Harrisons’ accusations of prejudice, plotting, sabotage and so on, on the part of Maskelyne and the other Commissioners were mostly or even wholly untrue. For example, Derek Howse and Humphrey Quill both concluded that the Astronomer Royal conducted the trials of Harrison’s watch ‘H4‘ at the Greenwich observatory fairly, rather than sabotaging them or misrepresenting results as has been suggested. Maskelyne could have given the clockmakers some more leeway in his interpretation of the results, but that he did not do so was probably not due to ill intent or severe prejudice. Howse, Quill and other authors do not believe that the astronomer had a deeply seated antagonism towards the Harrisons at all, never mind allowing such an emotion to impact the conduct of his positions at Greenwich and as a Commissioner – although he was no doubt offended by the increasingly serious accusations that they lobbed against him in later decades. Maskelyne (pictured below) was in fact one of the people who proposed John Harrison’s son William for election as a Fellow of the Royal Society in 1765, despite the working tensions that then existed between them.

It also seems unlikely that prejudice or ill will was what prevented the Commissioners of the Longitude from giving Harrison one of the official longitude rewards established by the Act of 1714 – although again, they no doubt grew increasingly irritated as the Harrisons cast verbal and printed aspersions upon their intellectual abilities and moral fibre during the 1760s and 1770s. The majority of them seemed to have truly believed that the clockmaker had not yet fulfilled the requirements of the original and later Acts because he had not proved that his inventions could be reproduced for widespread use rather than being brilliant one-offs, just as surely as the Harrisons believed that they did not have to prove this and that they should have already been given the largest longitude reward years before. When John first petitioned Parliament asking for satisfaction, he was not able to convince the majority of MPs that the Commissioners had not followed the ‘letter of the law’. His second petition successfully sought recompense despite those laws, in light of his brilliant innovations, years of dedicated work, and advanced age.

Nevil Maskelyne insisted when writing much later in 1800 that, ‘He always allowed Mr. Harrison’s great merit, as a genius of the first rate, who had discovered, of himself, the causes of the irregularities of watches, and pointed out the means of correcting these errors in a great degree, in the execution of a portable time-keeper, of a moderate size, to be put on board of ship, not liable to disturbance from the motions of the ship, and exact enough to keep time within two minutes in six weeks. He made no opposit[ion] to Parliament granting him the remainder of the reward of £20,000; but only to the Board of Longitude doing it; as he had not submit[ted] to trials [i.e. as dictated by the related legislation], and those sufficient to enable the Board to give it to him according to the terms of the Act.’

To find out why Maskelyne and the Commissioners of Longitude had good reasons to encourage the improvement of the lunar-distance method as well as that of Harrison’s chronometers, read Part Two of ‘Rehabilitating Nevil Maskelyne’ tomorrow.


Picture credits: Portrait of Capt James Cook by Nathaniel Dance © NMM BHC2628; engraving of Nevil Maskelyne, Wikimedia Commons.