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Henry Oldenburg here comments on someone else's suggestions for calculating longitude on the basis of the sun and a star. Although the text mentions the Italian astronomer Giovanni Battista Riccioli (1598-1671), Oldenburg seems to imply that he is not directly commenting on his book 'Geographiae et hydrographiae reformatae' [Reformed geography and hydrography] (Bologna, 1661). Includes two geometrical diagrams in the text.

Subject: Astronomy / Navigation

Reference number
Earliest possible date
c17th Century
Physical description
Ink on paper
Page extent
1 page

Creator name

Henry Oldenburg

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Henry Oldenburg, Paper, 'On calculating longitudes' by Henry Oldenburg, c17th Century, CLP/8i/16, The Royal Society Archives, London,, accessed on 21 July 2024

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  • Classified Papers

    Dates: 1592-1741

    The 'Classified Papers' of the Royal Society are papers from British and international natural philosophers and scholars categorised according to subject areas.

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