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The Royal Society: Science in the Making

Paper, 'A spirit level to be fixed to a quadrant for taking a meridional altitude at sea when the horizon is not visible' by John Hadley

Reference number: CLP/8ii/44

Date: 10 January 1733

Description

Hadley states that 'The necessity of seeing the horizon, in order to find the latitude of a ship at sea, has always been so great an inconvenience. Any method for determining it without the help of the horizon, will be of considerable use.' His spirit level consists of a glass tube bent into a curved shape, 'containing such number of degrees as will be most suitable to the degree of exactness with which the observation can be made', and filled with liquid.

Subject: Astronomy / Navigation / Scientific apparatus and equipment

Read to the Royal Society on 10 January 1733

Published in Philosophical Transactions as 'A spirit level to be fixed to a quadrant for taking a meridional altitude at sea, when the horizon is not visible'

Reference number
CLP/8ii/44
Earliest possible date
10 January 1733
Physical description
Ink on paper
Page extent
4 pages
Format
Manuscript

Creator name

John Hadley

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Citation

John Hadley, Paper, 'A spirit level to be fixed to a quadrant for taking a meridional altitude at sea when the horizon is not visible' by John Hadley, 10 January 1733, CLP/8ii/44, The Royal Society Archives, London, https://makingscience.royalsociety.org/items/clp_8ii_44/paper-a-spirit-level-to-be-fixed-to-a-quadrant-for-taking-a-meridional-altitude-at-sea-when-the-horizon-is-not-visible-by-john-hadley, accessed on 20 April 2025

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https://makingscience.royalsociety.org/items/clp_8ii_44/paper-a-spirit-level-to-be-fixed-to-a-quadrant-for-taking-a-meridional-altitude-at-sea-when-the-horizon-is-not-visible-by-john-hadley

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  • Classified Papers

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

    Dates: 1592 - 1741

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