Papers of the Board of Longitude : Papers regarding the public trials and improvements of clocks and chronometers, 1779-1826

Papers of the Board of Longitude

<p style='text-align: justify;'>A diverse set of documents dating from the 1770s to the 1820s. These papers relate to the ownership, trialling, movement, and use of timekeepers by the British government during this period. The government explored the use of timekeepers in their search for an accurate method of finding longitude at sea. The regulation and procedures for acquiring timekeepers and creating rules for their use changed during this period. However, it is clear from the documents that even by the 1820s the Board of Longitude and the Admiralty had not established definitive procedures. Neither could find a foolproof method to make timekeepers work as trusted navigational devices.</p><p style='text-align: justify;'>The <a href='' onclick='store.loadPage(1);return false;'> 'Instructions for the use of Chronometers Supplied to His Majesty's Ship's' (RGO 14/23:100)</a> in this volume demonstrate the drawn-out and recalcitrant nature of the process of creating a system in which timekeepers could be trusted to be a solution. Probably written around 1819 by a member of the Admiralty, this document is clearly concerned with making sure the capabilities and capacities of delicate and 'expensive' instruments were understood by their users. The advantages given are interesting and relay the two uses of timekeepers on Royal Navy [<a target='_blank' class='externalLink' href='http://collections.rmg.co.uk/collections/objects/243286.html'><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>] ships. The first is to give confidence and security to the navigation of the ship or vessel with the aim to 'shorten the voyage'. The second is to enable officers to produce data for geographic surveying. Most striking is how these aims differ from the purpose of finding Longitude at sea given in the majority of accounts of the pursuit: namely, to prevent shipwrecks. Here the role of timekeepers on board ships clearly appears to be a lot less about immediate concerns of 'where the ship is', but 'how to reduce the length of a voyage'. To shorten the length of a voyage had apparent economic benefits. Shorter voyages meant ships be equipped with fewer provisions. They also meant that crew, particularly seamen, could be paid much less in wages. The idea that ships of the Royal Navy and East India Company [<a target='_blank' class='externalLink' href='http://collections.rmg.co.uk/collections/objects/970.html'><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>] might be prevented from sinking was clearly a boon, but perhaps the more administrative and economic concerns of the English capital should be remembered when thinking about the quest for finding a solution for longitude at sea.</p><p style='text-align: justify;'>This volume's first document also highlights the degree to which the Board of Longitude and Admiralty were concerned about cost. Written by William Marsden (see <a target='_blank' class='externalLink' href='http://www.npg.org.uk/collections/search/portrait/mw04225/William-Marsden'>portrait</a> at the National Portrait Gallery) in 1805, it attempts to set out a clear procedure through which the Admiralty could trial, value and purchase timekeepers. The timing of this document is far from coincidental, as it was sent to the Board of Longitude during the height of its problems dealing with Thomas Earnshaw [<a target='_blank' class='externalLink' href='http://collections.rmg.co.uk/collections/objects/14148.html'><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>] and John Roger Arnold (see <a target='_blank' class='externalLink' href='http://collectionsonline.nmsi.ac.uk/detail.php?type=related&kv=25907&t=people'>portrait</a> at the Science Museum), and their claims for reward (see <a href='/view/MS-RGO-00014-00026'> (RGO 14/26)</a> and <a href='/view/MS-RGO-00014-00027'> (RGO 14/27)</a>). This proposal calls for the valuation of timekeepers on the basis of their performance in a range of trials, rather than on the value set by the maker. This proposal was radical because it signalled a significant change in the government's relationship with the clock and watchmaking community. They moved from trying to gauge the price of timekeepers and encourage their manufacture at a low rate (as can be seen in the Arnold and Earnshaw discussions and in the Board of Longitude's relationship with Thomas Mudge [<a target='_blank' class='externalLink' href='http://collections.rmg.co.uk/collections/objects/152338.html'><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>]) to explicitly setting prices based not on custom, but on experimental performance. Testing the rates of chronometers occupied an enormous amount of time and labour from the Board of Longitude and Admiralty from the late eighteenth into the early nineteenth century. It relied on rigorous tests at the Royal Observatory at Greenwich, and extensive amounts of time on voyages. An extensive record of this is to be found in this volume.</p><p style='text-align: justify;'>Eóin Phillips<br />History and Philosophy of Science<br />University of Cambridge<br /></p>