This thread collects useful resources for people who are interested on chronometers. If you have any suggestions on things to add to this list, please send me a PM. Basic Books This subsection is not meant to be an an exhaustive bibliography, but rather a mix of general introductions and standard reference books, with an emphasis on more easily obtainable ones. The next section contains a more extensive listing. Betts, Jonathan. 2006. Time Restored: The Harrison Timekeepers and R.T. Gould, the Man who Knew (Almost) Everything. Oxford University Press. ISBN: 978-0198568025. Dunn, Richard and Rebekah Higgitt. 2014. Finding Longitude. Glasgow: Collins. ISBN: 978-0007525867. Gould, Rupert T. 1923. The Marine Chronometer: Its History and Development. London: J.D. Potter. Gould, Rupert T. 1923/2013. The Marine Chronometer: Its History and Development. 2013 edition incorporating Gould's own amendments and additions from his original annotated manuscripts. With new illustrations and a foreword by Jonathan Betts. Woodbridge, Suffolk, England: The Antique Collectors' Club. ISBN: 978-1851493654. Mercer, Tony. 1991. Chronometer Makers of the World. With Extensive List of Makers and Craftsmen. London: N.A.G. Press. ISBN: 978-0719803406. Randall, Anthony G. 1991. The Time Museum Catalogue of Chronometers. With illustrations by David Penney. Rockford, Illinois: The Time Museum. ISBN: 978-0912947037. Sobel, Dava. 1996. Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time. Penguin Books. ISBN: 978-0007790166. Sobel, Dava and William J.H. Andrewes. 1998. The Illustrated Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time. Walker & Company. ISBN: 0-8027-1344-0 Whitney, Marvin E. 1991. The Ship's Chronometer. Cincinnati, Ohio: American Watchmakers Institute Press. ISBN: 978-0918845085. Whitney, Marvin E. 1992. Military Timepieces. American Watchmakers Institute Press. ISBN: 978-0918845146 Other Books These are more specialized or harder to obtain books. Andrewes, William J.H. (Ed.). 1996. The Quest for Longitude: The Proceedings of the Longitude Symposium, Harvard University, Cambridge, Massachussetts, November 4-6, 1993. Cambridge, MA: Harvard University Collection of Historical Scientific Instruments. ISBN-10: 0964432900; ISBN-13: 978-0964432901 Chamberlain, Paul. 1941. It's About Time. ISBN-10: 090047081X; ISBN-13: 978-0900470813. Mercer, Tony. 1978. Mercer Chronometers: Radical Tom Mercer and the house he founded. Ashford, Kent: Brant Wright Associates Ltd. ISBN-10: 090351219X; ISBN-13: 9780903512190 Mercer, Tony. 2003. Mercer Chronometers: History, Maintenance and Repair. ISBN-10: 0954052536; ISBN-13: 978-0954052539. Mercer, Vaudrey. 1975. John Arnold & Son Chronometer Makers 1975 + Supplement with updates. ISBN-10: 090118005X; ISBN-13: 978-0901180056. Mercer, Vaudrey. 1977. The Life and letters of Edward John Dent Chronometer Maker and some account of his Successors. ISBN-10: 0901180165; ISBN-13: 978-0901180162. Mercer, Vaudrey. 1981. The Frodshams - the Story of a Family of Chronometer Makers. ISBN-10: 090118022X; ISBN-13: 978-0901180223. Quill, Humphrey. 1966. John Harrison: The Man Who Found Longitude. London: Baker. Staeger, Hans. 1997. 100 Years of Precision Timekeepers from John Arnold to Arnold & Frodsham 1763-1862. Germany: Published by author. United States Department of the Navy, Bureau of Ships. 1948. Manual for Overhaul and Handling of Hamilton 35-Size Chronometer Watch, with Parts Catalog. NAVSHIPS 250-624-1 United States Department of the Navy, Bureau of Ships. 1948. Manual for Overhaul, Repair and Handling of Hamilton Ship Chronometer with Parts Catalog. NAVSHIPS 250-624. Von Bertele, Hans. 1991. Marine & Pocket Chronometers. West Chester: Schiffer Publishing. Online resources Board of Longitude (Cambridge Digital Library). Contains digitized copies of many of the late 18th and early 19th century primary source documents on the development of the chronometer in England. If you're reading some of the books on the history of chronometers (e.g., Gould's book), much of the primary sources they cite are available on this site. Some highlights: Arnold, John. 1791. Certificates and circumstances relative to the going of Mr. Arnold's chronometers. Arnold, John Roger. 1805. Explanation of time-keepers constructed by Mr. Arnold delivered to the Board of Longitude by Mr. Arnold, March 7th, 1805. Banks, Joseph. 1804. Protest against a vote of the Board of Longitude granting to Mr. Earnshaw a reward for the merit of his time-keepers. Board of Longitude. 1767. The principles of Mr. Harrison's time keeper. Board of Longitude. 1793. Objections to Mr. Mudge's pretensions to a Reward from parliament. By a committee of the board of longitude. Brühl, Hans Moritz. 1785. Three registers of a pocket chronometer, and the observations From which they were collected by Count De Bruhl, with an account from Vice-Admiral Campbell, of the first of Mr. Mudge's Time-Keepers, in a Voyage to and from Newfoundland. Dalrymple, Alexander. 1806. Longitude: a full answer to the advertisement concerning Mr. Earnshaw's timekeeper in the Morning Chronicle and Times, 4th Feb. and 13th Feb. 1806. Earnshaw, Thomas. 1805. Explanation of time-keepers constructed by T. Earnshaw, delivered to the Board of Longitude, March 7th, 1805. Maskelyne, Nevil. 1767. An account of the going of Mr. John Harrison's watch, at the Royal Observatory, from May 6th, 1766, to March 4th, 1767. Maskelyne, Nevil. 1792. An answer to a pamphlet entitled 'A narrative of facts,' lately published by Mr. Thomas Mudge, junior, relating to some time-keepers constructed by his father. Maskelyne, Nevil. 1804. Arguments for giving a reward to Mr Earnshaw, for his improvements on time-keepers. Mudge, Thomas. 1765. Thoughts on the means of improving watches and more particularly those for the use of the sea. Mudge, Thomas Jr. 1792. A narrative of facts, relating to some time-keepers constructed by Mr. Thomas Mudge for the discovery of the longitude at sea, together with observations on the conduct of the Astronomer Royal respecting them. Mudge, Thomas Jr. 1792. A reply to the Answer of the Rev. Dr. Maskelyne, Astronomer Royal, to A narrative of facts, relating to some time-keepers constructed by Mr. Thomas Mudge for the discovery of the longitude at sea. Mudge, Thomas Jr. 1799. A description, with plates, of the time-keeper invented by the late Mr. Thomas Mudge. The Royal Observatory Greenwich: In spite of the name, I don't believe this site is actually be affiliated with the Royal Observatory Greenwich. Nonetheless, it contains much valuable historical information. Notably it has an index that links to digitized copies of the Greenwich Observatory chronometer trial results from 1840 to 1914.