Finding Longitude

by National Maritime Museum

  The quality of the surveys and charts from the voyage (Fig. 18) showed that his trust in his instruments and newly trained crew was warranted. His findings that the rates of the timekeepers appeared to be affected by temperature variations also inspired many experiments after his return. Indeed, these same effects would be the subject of ongoing research throughout the nineteenth century.

  The Board of Longitude’s official instructions to their astronomers, and Vancouver’s personal enthusiasm in passing on his knowledge, emphasized the importance of training for the diffusion of the new navigational techniques into the Navy. This was true in the case of Matthew Flinders (1774–1814), who initially taught himself navigation and astronomy with the encouragement of his father and a cousin. Having gone to sea in 1790, Flinders developed his skills under Bligh (on his second successful breadfruit voyage in the Providence) and Captain John Hunter, with whom he sailed to New South Wales in 1795. After his arrival there, he spent time exploring and surveying, which brought him to the attention of Joseph Banks, who was promoting a systematic coastal survey of New Holland, as Australia was then known. At Banks’s instigation, a Royal Naval expedition was agreed, with Flinders given command of the sloop Investigator.

  Flinders set off in 1801. As for Vancouver’s voyage, the Board of Longitude lent its support and appointed John Crosley, a Greenwich-trained astronomer, who was given the usual instruments, including two box timekeepers made by Thomas Earnshaw (1749–1829, see Chapter 6), two by Arnold and sextants by Ramsden and Dollond. But Crosley left the ship at the Cape of Good Hope, complaining of ‘Chronic Rheumettisa in my knees and ... Gaut in my foot’.30 So the Board sent a replacement, James Inman, and supplied him with K3. With no Board of Longitude astronomer present in the meantime, the surveying and other work fell to Flinders and his brother Samuel, who had to learn to manage the timekeepers and other instruments. This was no easy matter. The observing tent was rotten, which made using the instruments difficult, and although the Earnshaw timekeepers performed quite well, two of the Arnolds stopped, one of them having made an ‘uncommon noise’.31 The new longitude methods could be successful but were fragile.

  Inman finally arrived in June 1803, only to find that the Investigator had been declared unseaworthy. Keen to execute his astronomical duties, he made a series of observations in Sydney but found that K3 was behaving erratically. He blamed the variable weather. Meanwhile, Flinders decided to return to England in the Porpoise. Within a week he was shipwrecked off the Australian coast. Returning by boat to Port Jackson, he set off again in a small schooner whose leaky condition forced him into the French island of Mauritius. Unbeknown to him, war with France had resumed and he was consequently held as a prisoner there for six and a half years. Inman made a swifter return to England and on the way used the timekeepers to help fix the position of Wreck Reef, where the Porpoise had come to grief (Fig. 19).

  Competition and cooperation

  Oceanic discovery, especially in the relatively unknown Pacific, was never the domain of Britain alone. Every European seafaring nation was seeking to explore and exploit previously unknown parts of the world and, just as on British voyages, the expeditions of other nations began to test and deploy the latest navigational methods.

  France’s first major venture was led by Louis-Antoine, Comte de Bougainville (1729–1811), in 1766–69. Having suffered heavy losses in the Seven Years War, France was looking for new regions to colonize. Bougainville was ordered to search for these and expand trading opportunities, particularly with China. Predating the Cook voyages, it was also the first such expedition to take scientific specialists, including naturalists and an astronomer, Pierre-Antoine Véron (1736–70), who experimented with several new navigational techniques and instruments. These included the intriguingly named mégamètre, an alternative to the octant, and different astronomical methods for finding longitude. Tahiti’s position, for example, was

  ascertained by eleven observations of the moon, according to the method of horary angles. M. Verron had made many others onshore, during four days and four nights, to determine the same longitude; but the paper on which he wrote them having been stolen, he has only kept the last observations, made the day before our departure. He believes their result exact enough, though their extremes differ among themselves 7° or 8°.32

  This method used measurements of latitude and the Moon’s altitude to determine its hour angle (its angle west of the observer’s meridian) and, by comparison with a reference location such as Paris, the longitude. Véron had some success with it but Bougainville and others preferred lunar distances, aided by the French astronomical almanac, the Connaissance des Temps.

  Among Bougainville’s crew was Jean-François de Galaup, Comte de Lapérouse (1741–c.1788). Twenty years later, by then a well-respected officer, Lapérouse was chosen to lead another major expedition intended to regain French prestige once more. As was by now the norm, Lapérouse’s ships, the Boussole and the Astrolabe, took specialists and the best instruments available, including five timekeepers by Ferdinand Berthoud, an English pocket timekeeper and at least four English sextants.

  The voyage nevertheless ended badly. Having set off in August 1785, Lapérouse’s ships spent time exploring and charting the Pacific. Early in 1788 they arrived in Botany Bay – just after Philip’s arrival with the First Fleet – and departed again the following month, having left copies of Lapérouse’s journals, charts and letters with Philip for transmission back to France. These last letters told how pleased Lapérouse was with the performance of the timekeepers but this was the last heard of the expedition. Its fatal end was deduced in 1826 and the ships’ sunken remains were only discovered in 1964, on the reefs of Vanikoro, New Caledonia. There was just one survivor, Jean-Baptiste Barthélemy de Lesseps, who had disembarked in Kamchatka in September 1787 with other copies of logs, charts and letters, and trekked across Siberia for over a year to deliver them to Paris. These would be the basis of the first published voyage accounts (Fig. 20).

  Fig. 19 – ‘Wreck Reef Bank’, by William Westall, August 1803

  {Ministry of Defence Art Collection / Photo: National Maritime Museum, Greenwich, London}

  Fig. 20 – Lapérouse’s officers with the islanders on Sakhalin in the north Pacific, from The Voyage of La Pérouse Round the World (London, 1798)

  {National Maritime Museum, Greenwich, London}

  While Alejandro Malaspina’s voyage of 1789–94 for the Spanish navy avoided the Pacific reefs, it too ended inauspiciously for its commander, who was arrested for conspiracy against the state just fourteen months after his return. He was imprisoned for six years and then exiled. The planning took place in happier times, however, as a response to Lapérouse’s voyage, and was intended to create much needed charts of the farthest reaches of the Americas. It was also to be an imperial inspection of Spain’s territories in South America and the Pacific.

  The voyage’s scientific aims allowed the Spanish to draw on the expertise of other European countries, Britain included. When it was realized that there were insufficient instruments in Cadiz, for example, steps were taken to purchase them in London. The hydrographer Alexander Dalrymple (1737–1808) was among those who advised on the equipment, which included astronomical instruments by Ramsden and Dollond, timekeepers by Arnold and the Nautical Almanac. The expedition also looked to France, purchasing two timekeepers by Berthoud and the Connaissance des Temps. Again, the expensive new technologies were precious. Malaspina’s diary recorded that to keep one of the Arnold timekeepers safe, he had it ‘hanging from my shoulder and held very close to my chest, so that there was no space for it to move, but it was rather cushioned by my own body’.33

  Cook’s influence on the Malaspina expedition was clear, right down to the name of one of the ships: Descubierta (Discovery). Like Cook’s expedition, it included artists, naturalists, astronomers and other experts, with surveying as one of its key activities. If anything, the results were even more impressive than Cook’s,
comprising one of the largest collections of data ever assembled by a single expedition, including 450 notebooks of astronomical and hydrographic observations, 1500 hydrographic surveys, 183 charts and 361 coastal views. The technologies and methods of longitude determination had been fully applied in this colossal collection. Unfortunately, little of it was published at the time – the achievements of the expedition suffered from their association with the outcast Malaspina, and were consigned to oblivion for more than a century.

  It was not just at sea that the new techniques could be applied. In the areas of North America under the control of the Hudson’s Bay Company, surveyors used sextants, artificial horizons and watches, together with the Nautical Almanac and Tables Requisite, to map the vast territory of Rupert’s Land, then part of British North America. They had great success but encountered many hazards. In December 1791, the surveyor Peter Fidler had just completed his sextant observations when a scaffold loaded with meat fell on him, although ‘by the greatest good luck the Instrument was unhurt.’34

  The most famous land-based expedition of the period was by Meriwether Lewis and William Clark, who in 1804–06 crossed the United States of America to find a ‘direct & practicable communication across this continent, for the purposes of commerce’ and so link America’s Atlantic and Pacific coasts.35 Thomas Jefferson had spent twenty years considering this ambitious plan by the time he became President in 1801. Once in power, he pushed ahead a project that would symbolize the political and geographical aspirations of the young republic.

  Jefferson was eager that Lewis and Clark deploy the latest instruments and techniques, and enlisted the help of the American Philosophical Society. Robert Patterson, professor of mathematics at the University of Pennsylvania, prepared material for field use, including forms for lunar distances, confident that his system for calculating longitude was ‘easy even to boys or common sailors of moderate capacities’.36 The expedition was also supplied with appropriate equipment, including an octant, a sextant, artificial horizons, a gold-cased chronometer by Arnold and the Nautical Almanac. Yet the observers’ inexperience, compounded by the vagaries of the timekeeper, rendered the results disappointing. The best data came from dead reckoning and the more straightforward latitude observations. Nonetheless, the explorers returned with a remarkable collection of information about the people, flora, fauna and geography of the vast regions they had crossed, allowing the first accurate maps to be produced.

  Although they formed just a fraction of maritime activity in the period, the voyages of exploration of the late eighteenth century showed that timekeeper and astronomical methods of longitude determination could be applied at sea. As the decades progressed, more people were trained and more instruments became available.

  Yet it was a slow process and widespread adoption was not inevitable. Thomas Brisbane, astronomer and former Governor of New South Wales, recalled that on a naval expedition in 1795 ‘there were perhaps not ten individuals who could make a lunar observation’.37 Timekeepers were gradually becoming more common too but remained rare until the nineteenth century. Small wonder, then, that Matthew Flinders could write about the new navigational techniques as curiosities in a whimsical biography of his seafaring cat, Trim:

  Trim took a fancy to nautical astronomy. When an officer took lunar or other observations, he would place himself by the Time-keeper, and consider the motion of the hands, and apparently the uses of the instrument, with much earnest attention; he would try to touch the second hand, listen to the ticking, and walk all around the piece to assure himself whether or no it might not be a living animal. And mewing to the young gentleman whose business it was to mark down the time, seemed to ask an explanation. When the officer had made his observation, the cry of Stop! roused Trim from his meditation; he cocked his tail, and running up the rigging near to the officer, mewed to know the meaning of all those proceedings.38

  Maritime trading enterprises such as the East India Company also had an interest in the development of accurate navigational techniques, and their officers and surveyors were notably early adopters, but it was a piecemeal process. Dead reckoning remained the norm on merchant vessels worldwide until around the 1830s, when more and more began to use chronometers. On the occasions when lunars were used, it was as a check for positions established by dead reckoning or, later on, by chronometer.

  The seemingly slow take-up of new navigational techniques and equipment has often been put down to mariners’ inherent resistance to change. However, it might be more appropriate to ask why anyone risking their life at sea should adopt a new technique or instrument without reasonable assurance of the benefit. It needed to be absolutely clear that the new methods offered tangible improvements and were easy to use, reliable and affordable. There also had to be a support system in place to supply and maintain the appropriate tools and to teach sailors how to use them. Both new methods for finding longitude could seem questionable by these criteria. Although the Nautical Almanac and tabulated forms speeded up the calculations for the lunar-distance method, laborious mathematics still faced the mariner wishing to use the heavenly bodies. The timekeeper method required similar calculations for determining local time and the watch’s rate. This cannot have suited every aspiring navigator.

  In the years before large-scale production of marine timekeepers, their reliability could not be taken for granted and some sceptics voiced their concerns about trusting them. William Wales had these doubters in mind when he railed against those whose efforts were ‘bringing timekeepers into disrepute, and ... defeating the endeavours of the Board of Longitude, who have been labouring incessantly for the last 30 years to establish the use of them’.39 Even after the East India Company put a column for longitude by chronometer in its log-books in 1791, captains began their daily reckoning not from this position but from the previous day’s estimation by dead reckoning.

  Yet there were successes. From the 1760s onwards, the new methods were exploited, albeit in a specialist capacity, for surveying and improving the charts on which navigation depended. Positive reports in published voyage accounts, and the gradual spread of officers who had learned the techniques on voyages of exploration, encouraged their use more routinely. Combined with support from the Board of Longitude, Royal Navy and East India Company, this would pave the way for formal and widespread adoption in the nineteenth century. For that to happen, however, there needed to be great changes in the production of timekeepers and observing instruments to make them more accurate, more reliable and, above all, more affordable.

  CHAPTER 6

  COMMERCE AND CREATIVITY

  Were we required to characterise this age of ours by any single epithet, we should be tempted to call it, not an Heroical, Devotional, Philosophical, or Moral Age, but, above all others, the Mechanical Age.

  Thomas Carlyle, ‘Signs of the Times’, Edinburgh Review, 18291

  Between the 1770s and 1830s, changes in the manufacturing of the new instruments for measuring longitude made them cheaper and more widely available. These developments relied on many things: skilled artisans; well-managed systems for coordinating work; technical refinement; business acumen; and state encouragement, in part through the Board of Longitude. As markets developed, the canniest entrepreneurs were able to take advantage of the opportunities they offered. Competition was intense, however. Business rivalries could become bitter and attempts to profit from invention often came to nothing.

  The wider transformation of Britain in this period, usually known as the Industrial Revolution, had a number of interlinked roots, including the introduction of new ways of using energy sources such as coal, harnessing steam and water power, and the beginnings of factory systems of production. These changes were not confined to Britain but had far-reaching effects there, fostered by relative political stability and an intellectual climate that encouraged the exchange of ideas through diverse publications, new organizations such as the Society for the Encouragement of Arts, Manufactures and Commerce, and
a growth in public lectures and scientific demonstrations throughout the country. It was above all an age of innovation, as satirists reminded the public (Fig. 1). But innovation could be unwelcome. After the ending of the traditional procession to public hangings at Tyburn in 1783, Samuel Johnson complained that,

  The age is running mad after innovation; all the business of the world is to be done in a new way; men to be hanged in a new way; Tyburn itself is not safe from the fury of innovation.2

  Fig. 1 – ‘March of Intellect – Lord, how this world improves as we grow older’, by William Heath, published by Thomas McLean, London, 1829

  {National Maritime Museum, Greenwich, London, Courtesy of Richard Dunn}

  Although there were countless inventions, from the steam engine to the iron boat, their impact was normally felt only decades after their first appearance, once their teething problems were eliminated and they had been refined and made cost-effective. As Daniel Defoe had already noted in 1726, this was something at which British artisans and entrepreneurs excelled:

  most of our great Advances in Arts, in Trade, in Government and in almost all the great Things, we are now Masters of and in which we so much exceed all our Neighbouring Nations, are really founded upon the Inventions of others.3

  These were skills that would be important in the development of instruments for determining longitude. At the same time, Britain’s commercial landscape provided fertile ground in which ingenious and enterprising individuals could use the market to exploit their ideas. It was the age of the technological entrepreneur, made prosperous from the fruits of his own invention (see Figs 5, 7 and 11).