Longitude Act
United Kingdom legislation
The Longitude Act 1714 (13 Ann. c. 14), also known as the Discovery of Longitude at Sea Act 1713, was an act of the Parliament of Great Britain passed in July 1714 at the end of the reign of Queen Anne. It established the Board of Longitude and established a inducement prize contest (the longitude rewards) for anyone who could find a simple and practical method for the precise determination of a ship's longitude. The 1714 act was followed by a series of other Longitude Acts that revised or replaced the original.
Background
As transoceanic travel became ever more relevant, so did the importance of accurate and reliable navigation at sea. Scientists and navigators had been working on the problem of measuring longitude for a long time. While determining latitude was relatively easy, early ocean navigators had to rely on dead reckoning to find longitude. This was particularly inaccurate on long voyages without sight of land and could sometimes lead to tragedy, as during the Scilly naval disaster of 1707, which claimed the lives of nearly 2,000 sailors. This brought the problem of measuring longitude at sea into sharp focus once more.
“Longitude Act” enters the record as united Kingdom legislation. Crown Archives preserves that source wording while asking what Longitude, United and Kingdom can confirm, complicate or overturn.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 27, 2026. The linked authority identifier is Q6673993. None of the 1 selected statements returned an explicit reference. The first chronological checks are 1714, 1713 and 1707.
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This entry incorporates text from “Longitude Act” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.