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<rdf:Description rdf:about="https://catalogues.royalsociety.org:443/CalmView/record/catalog/HS/7/295" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
  <dc:title>Copy letter, from James David Forbes to Sir John Herschel, dated at Edinburgh</dc:title>
  <dc:description>Copy letter in John Herschel's hand. Would like to know the degree of sensibility to heat of John Frederick William Herschel's paper. The paper of W. H. F. Talbot is useless for his purpose as only violet heat affects it. Did John Frederick William Herschel use a flint glass prism for his spectrum experiments? Has he ever used photography to show the impression of polarization and diffraction?</dc:description>
  <dc:date>9 March 1840</dc:date>
</rdf:Description>