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Letter, from Robert Hooke to Henry Jacobs, dated at London

Reference number: EL/H3/66

Date: 10 October 1681


Hooke has collated observations of the eclipse (unclear whether it is of the sun or moon) by Flamsteed at Derby, by Bullialdus and Cassini at Paris, by Hevelius at Gdansk; asks for compass readings ('variation of the magnetic needle') at Lisbon; developments with determining longitude

Reference number
Earliest possible date
10 October 1681
Page extent
1 page

Creator name

Robert Hooke

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Robert Hooke, Letter, from Robert Hooke to Henry Jacobs, dated at London, 10 October 1681, EL/H3/66, The Royal Society Archives, London,, accessed on 23 July 2024

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  • Early Letters

    Dates: 1613-1740

    The archival collection known as 'Early Letters' is composed of original manuscript letters sent to, or collected by, the Royal Society from English and foreign correspondents.

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