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<rdf:Description rdf:about="https://catalogues.royalsociety.org:443/CalmView/record/catalog/HS/17/423" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
  <dc:title>Letter, from [A. J. F.] Yvon Villarceau to Sir John Herschel, dated at Paris</dc:title>
  <dc:description>Autograph letter signed by sender. Thanks for John Frederick William Herschel's 'Catalogue of Nebulae.' Comments on the problems of accuracy in Yvon Villarceau's meridian instrument due to fluctuating temperatures and other problems. Also refers to geodetic and trigonometric considerations.</dc:description>
  <dc:date>17 November 1864</dc:date>
</rdf:Description>