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Found: John Arnold’s Marine Timekeeper #4

A marine pocket watch, believed to have been made as part of the race to determine longitude at sea, was recently authenticated by curator of Horology, Rory McEvoy of the Royal Observatory, Royal Museums Greenwich, England. Mr. McEvoy verified that the pocket watch is #4 in a series of five marine timekeepers made by John Arnold of London, circa 1772.

John Arnold (1736-1799) was one of several men competing for the Board of Longitude prize to produce a marine timekeeper that would ensure safe and accurate navigation. Only a few of these paradigm-shifting time pieces from this period of technological development are known and in public hands, and the discovery of Arnold’s #4 adds significantly to the scientific record. Arnold’s #3 is in the collections at the British Museum; #1, 2 and 5 in the series are missing.

Most people familiar with the race for longitude know that John Harrison (1693 – 1776) was awarded the Board of Longitude’s principal award for producing the farnold_watch_inscriptionirst accurate marine timekeeper that could ascertain longitude at sea. Arnold, a competitor for the prize, introduced many original ideas and perfected those of others. He is credited with producing timekeepers that were accurate, reliable, simpler to construct, and affordable. In the early 1770s, while his see-saw escapement timekeepers were away on sea trials, Arnold started designing pocket watches with pivoted detent escapements like #4. In 1773 when Constantine John Phipps set out on his voyage to the North Pole one of Arnolds’ pivoted-detent watches (either #3 or #4) went along.

By 1792 Arnold #4 had made its way into the hands of Newporter Peleg Clarke. Descended from one of Newport’s first English settlers, Clarke was a wealthy merchant of the American colonial period who likely bought the watch from Arnold during a trip to London. He was an eyewitness to the Boston Tea Party and recorded his impressions in a letter now also in the collections at the NHS. Arnold #4 was passed down in the Clarke family and used as a pocket watch for over 200 years, until it was donated to the Newport Historical Society in 1997.

Mr. McEvoy spoke at the Newport Historical Society on this race for longitude, John Harrison, and John Arnold’s #4. Video produced for the Newport Historical Society by Tree of Life Productions, LLC .

For more information about Peleg Clarke witnessing the Boston Tea Party, read this History Bytes post.