National Maritime Museum Manuscripts : Letters from the Longitude Commissioners to the Navy Board concerning John Harrison and Christopher Irwin

Board of Longitude

National Maritime Museum Manuscripts

<p style='text-align: justify;'>One of a set of eight letters sent from the Commissioners of Longitude to the Admiralty which help to show the day-to-day workings of the Board. While the Commissioners were empowered to allocate reward money up to the amounts specified in the various Acts, they did not have their own money but had to apply for it out of naval funds. Likewise, they did not have their own budget to cover expenses and running costs but had to apply for these. Such financial questions are the focus of these letters. All but one date from the 1760s. Each is signed by a number of Commissioners, complete with red or black wax seals.</p><p style='text-align: justify;'>The question of expenses and running costs was dealt with in a <a href='/view/MS-ADM-A-02551/6'> letter (ADM/A/2551: 2:1-2:2)</a> in September 1763. This informed the Navy Board of two new payments that an order in council by George III had agreed should be made for the Commissioners. The first was to cover the expenses of the Professors from Oxford and Cambridge who were <i>ex officio</i> members of the Board and had until then been paying for their own travel and board to attend meetings. They were now to be paid £15 each per meeting. The second, was to cover the expenses of appointing a secretary to the Board, the first of whom was John Ibbetson, and would receive £40 per year. The necessity of such a secretary was explained to the king in a letter (incorporated in the king's order) which the Commissioners included with their letter to the Admiralty. They <a href='/view/MS-ADM-A-02551/8'> explained (ADM/A/2551: 3:2)</a> that, 'all the Papers and Minutes since the first appointment of Commissioners … are in great Disorder and Confusion,' suggesting that the <a href='/view/MS-RGO-00014-00005/5'> minutes (RGO 14/5: 1)</a> of meetings before 1763 were written up at this much later point.</p><p style='text-align: justify;'>The rest of the letters deal with the Commissioners' requests for the Navy Board to make payments on their behalf in respect of trials and awards. Two (<a href='/view/MS-ADM-A-02528'> (ADM/A/2528)</a> and <a href='' onclick='store.loadPage(1);return false;'>ADM/A/2539: 1:1-1:4</a>) deal with money to be given to John Harrison to conduct trials of his time-keepers in 1761 and 1762. Two others (<a href='' onclick='store.loadPage(5);return false;'>ADM/A/2539: 2:1-2:3</a> and <a href='/view/MS-ADM-A-02551/4'> (ADM/A/2551: 1:1-1:4)</a>) ask for payments to Christopher Irwin for trials of his marine chair. <a href='/view/MS-ADM-A-02551/1'> One (ADM/A/2551: 1:1)</a> allocates an advance to Charles Green, assistant to the Astronomer Royal, to cover his preparatory expenses for the 1763 trial of Harrison's <a target='_blank' class='externalLink' href='http://collections.nmm.ac.uk/collections/objects/79142.html'>watch</a> on a voyage to Barbados, on which Green accompanied Nevil Maskelyne. <a href='/view/MS-ADM-A-02551/15'> Another (ADM/A/2551: 4:1-4:3)</a> deals with the role of John Bradley in this trial, who was to be astronomer on the ship with Harrison. The letter asks for the Commissioner at Portsmouth, Hughes, to arrange for an observatory to be constructed for Bradley, and to oversee the observations and the multiple locks and keys of the box which was to house Harrison's watch.</p><p style='text-align: justify;'>Further letters make payments of reward money. <a href='/view/MS-ADM-A-02572/3'> One (ADM/A/2572:3)</a> asks for the Navy Board to pay money to Professor Leonhard Euler and to Tobias Mayer for their work on the lunar distance method, which had been agreed by the 1765 Act. Other small rewards are paid to Catherine Price for <a href='/view/MS-ADM-A-02572'> donating (ADM/A/2572)</a> the papers of her father Edmond Halley, a past Astronomer Royal, and to Ralph Walker for his <a href='/view/MS-ADM-A-02869'> invention (ADM/A/2869)</a> of a meridional compass. This last reward is the only letter not from the 1760s, written in 1795.</p><p style='text-align: justify;'>Katy Barrett<br />History and Philosophy of Science<br />University of Cambridge<br /></p>