<?xml version="1.0" encoding="utf-8"?>
<rdf:Description rdf:about="https://catalogues.royalsociety.org:443/CalmView/record/catalog/CLP/1/6" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
  <dc:title>Letter, regarding Charles Brown's rotula arithmetica from unknown author to unknown recipient</dc:title>
  <dc:description>Letter regarding the invention by Charles Brown [erroneously referred to as George Brown in the letter] of a machine to aid in subtracting, multiplying and dividing.

Subject: Mathematics

Read to the Royal Society on 25 January 1698</dc:description>
  <dc:date>[1698]</dc:date>
</rdf:Description>