(:title Quixsum, model C, ~1930, imperial feet, inches and fractions adding machine:) %center% http://meta-studies.net/pmwiki/uploads/Quixsum.gif Patented in 1923 (US1497570, dated 25 August 1923 by F. Leitner) and manufactured by the Precision Adding Machine Co. Inc. of Providence, RI, Charlotte, North Carolina, USA, this stylus operated large dial adding machine was capable of adding fractions of an inch, inches, feet and hundreds of feet. This is the model C, probably produced in ~1930 but with its serial number illegible.