The Society has only a few 'ancient' manuscripts, such as copies of the Alphonsine tables. The bulk of the archive holdings comprise observational and other scientific material, plus administrative papers and correspondence from the mid-18th century to the 1940s.
A major group is the Herschel Archive, the papers of Sir William, Sir John, and Miss Caroline Herschel, which is stored elsewhere and is made available in microfilm and in CD form at Burlington House (the CD is available for sale).
The Catalogue of RAS Archives and Manuscripts, compiled by Dr J. A. Bennett and originally published in the Memoirs of the Royal Astronomical Society vol. 85 (1978), is available online.
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