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Rev. William Mitchel on his improved quadrant, 1787 - 1788

Reference Code: GBR/0180/RGO 14/38: 117-133

Scope and Contents

Papers and three letters, chiefly concerning Mitchel's improved quadrant and its use for the four most important operations in navigation: finding the variation of the needle at sea, finding the latitude at sea, finding the apparent time at sea, and finding the longitude by Jupiter's satellites or the moon. In the final letter of the series, dated 14 July 1788, Mitchel states that he had 'laid aside' his quadrant method and now proposed a method of finding longitude by the stars or by the satellites of Jupiter [RGO 14/38: 133].


  • 1787 - 1788

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17 folio(s) (17 ff.) : Paper

Language of Materials



Mitchel, William

Finding aid date

2011-12-07 17:59:09+00:00


Repository Details

Part of the Cambridge University Library Repository

Cambridge University Library
West Road
Cambridge CB3 9DR United Kingdom

The UK Archival Thesaurus has been integrated with our catalogue, thanks to Kings College London and the AIM25 project for their support with this.