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<rdf:Description rdf:about="https://catalogues.royalsociety.org:443/CalmView/record/catalog/HS/18/204" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
  <dc:title>Extract of letter, from Sir John Herschel to William Whewell, dated at Collingwood</dc:title>
  <dc:description>Extract of letter in John Herschel's hand. Presents a detailed discussion of the state of double star astronomy, including number known and number that are probably gravitationally linked. Gives an extended critique of William Whewell's Lectures on Systematic Morality, arguing that William Whewell's system is ultimately a happiness-of-mankind system and consequently rests on expediency considerations.</dc:description>
  <dc:date>29 June 1846</dc:date>
</rdf:Description>