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Letter, 'Of the Brahmin observatory at Benares [Jantar Mantar, Varanasi]' from Robert Barker to John Pringle

Reference number: L&P/6/248

Date: 1777


Description of the astronomical observatory Jantar Mantar, Varanasi completed in 1737 by order of Raja Jai Singh (1681-1743), founder of Jaipur.
The paper describes the observatory as disused, with lower parts of the edifice 'converted into a stable'. The edifice is incorrectly dated 'said to have been erected two hundred years' by Emperor Akbar (reign 1556-1605). Written by the Commander in chief of the British Forces in Bengal, Robert Barker, FRS. Barker recognises the 'mathematical exactness' of the stone construction as modern and notes the extraordinary 'serenity and clearness of the atmosphere in the night time' outside of monsoon season.

Jantar Mantar is part of a complex of five observatories, the site in Varanasi were built atop a 17th century palace and contained at least seven instruments, only five are described with the largest sundial, likely the 6.8m high Samrat Yantra, is described in details, including its dimensions and latitude at the end of the letter.

Includes 3 plates, one watercolour view of Jantar Mantar, a watercolour perspective and cross-section of Samrat Yantra (sundial), attributed to then Lieuntenant Colonel Archibald Campbell, chief-engineer for the East India Company (future colonial governor of Madras, Georgia and Jamaica).

Subject: Astronomy

Published in Philosophical Transactions, as 'An account of the Bramin's observatory at Benares. By Sir Robert Barker, Knt. F.R.S.; in a letter to Sir John Pringle, Bart. P.R.S.'
Read 29 May 1777

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13 pages

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Robert Barker

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Robert Barker, Letter, 'Of the Brahmin observatory at Benares [Jantar Mantar, Varanasi]' from Robert Barker to John Pringle, 1777, L&P/6/248, The Royal Society Archives, London,, accessed on 18 April 2024

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  • Letters and Papers

    Dates: 1741-1806

    'Letters and Papers' contains the scientific correspondence sent to the Royal Society through the 18th century, many of which were published in its journal.

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