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Papers of the Board of Longitude : Correspondence regarding methods of establishing longitude by lunar distances

Papers of the Board of Longitude

<p style='text-align: justify;'>This volume contains correspondence relating to methods, accuracy and instruments for the lunar distance method [<a target='_blank' class='externalLink' href=''><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>] of finding longitude at sea. The Board of Longitude received these letters between 1783 and 1825. Tobias Mayer had vastly improved the lunar distance method thirty years before and his widow received a reward for his work in the <a href='/view/MS-RGO-00014-00001/63'> 1765 Act (RGO 14/1:32r)</a>. The <i>Nautical Almanac</i> had also been published under the auspices of the Board from this point. Most correspondents here therefore seek to improve the methods of calculation, the means of teaching and recording those methods, or the necessary instruments for taking observations. In 1788, William Storer referenced directly the <a href='/view/MS-RGO-00014-00001/85'> 1775 Act (RGO 14/1:43r)</a> in his proposal. This Act re-stated the purposes of the Board and brought the lunar distance method and Nautical Almanac to the fore. A number of correspondents, however, seemed unaware of these developments and pieces of legislation. They continued to present a method of using lunar movements as their own unique discovery. William Fairman who opens the volume would be a case in point.</p><p style='text-align: justify;'>This volume is marked by mostly brief correspondence and evident deference to the judgement of the Commissioners. This contrasts with the vociferous support of their proposals over periods of years by correspondents in volumes <a href='/view/MS-RGO-00014-00039'> (RGO 14/39)</a> or <a href='/view/MS-RGO-00014-00040'> (RGO 14/40)</a>. The marked exception to this peaceful picture is the correspondence of John Turner. This fills almost half of the volume and stretches from 1795 to 1818. Turner refuses to accept the Board's statement that his method was not new. He is also unique in this volume, too, for <a href='' onclick='store.loadPage(173);return false;'> asserting the merits of the lunar distance method over timekeepers (RGO 14/32:88r)</a>. He also <a href='' onclick='store.loadPage(251);return false;'> reminds the Commissioners (RGO 14/32:127r)</a> of what he saw as their duty, saying 'if I offend in writing on this subject, I most humbly ask pardon, But as there is an Act of Parliament offering great rewards to any Person or Persons who discover a method of finding the Longitude within certain limits of the Act, the reward is to be paid according to the discovery.' Eventually an 1812<a href='' onclick='store.loadPage(299);return false;'> letter (RGO 14/32:151r)</a> from him, simply has 'no answer' written in Thomas Hurd [<a target='_blank' class='externalLink' href='!csearch;authority=agent-178430;makerReference=agent-178430'><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>]'s (Secretary to the Board) hand at the bottom.</p><p style='text-align: justify;'>It is also striking what a range of backgrounds and areas the correspondents come from. Michel Cavé wrote from France, W.L. Krafft from St Petersburg, and Adolphus Palmedo from Sardinia. Correspondents included school masters Joseph Golson and John Abram, William Storer, Professor of Optics to George III [<a target='_blank' class='externalLink' href=''><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>] and Charles White a naval officer. John Abram's proposal is interesting both in offering his design of <a href='' onclick='store.loadPage(361);return false;'> cards (RGO 14/32:186r)</a> that allow students to learn and record the method more easily, and in asking only for the Board's permission to dedicate the cards to it on publication. A number of sections of the correspondence are part of larger groups bound elsewhere in the Board archives. Storer, for instance, also features in <a href='/view/MS-RGO-00014-00012/257'> Volume 12's 'Miscellaneous Petitions and Memorials' (RGO 14/12:433r)</a> and Mendoza de Rios' improved tables are discussed in <a href='/view/MS-RGO-00014-00055/299'> volume 55 (RGO 14/55:107r)</a>. He is a rare example from this volume of a correspondent who was supported financially by the Board.</p><p style='text-align: justify;'>Of interest also is the archival history of this volume, which appears to have been arranged and labelled prior to the process which put the Board archives in their current state in the 1850s under the auspices of the then Astronomer Royal George Airy [<a target='_blank' class='externalLink' href=''><img title="Link to RMG" alt='RMG icon' class='nmm_icon' src='/images/general/nmm_small.png'/></a>]. Pieces of binding and catalogue labels at the front show an older casing for this volume, and older 'file dividers' have been preserved. The correspondence has also, here, been arranged chronologically where in other volumes it appears alphabetically by name.</p><p style='text-align: justify;'>Katy Barrett<br />History and Philosophy of Science<br />University of Cambridge<br /></p>

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