Original patent lithographs for Mercedes Büro-Maschinen Werke AG's improvements in the calculating machine, five pages, four 12.25 x 10.25 (linen-backed) and one 7 x 10.25 (not linen-backed), January 11, 1932. The diagrams feature multiple views of the improved calculating machine's design, including close-ups and blow-outs of its internal mechanisms. The top borders read: "365,058 Complete Specification." The lower borders feature the printed text: "Charles & Read Ltd. Photo Litho." The left borders read: "This Drawing is a reproduction of the Original on a reduced scale." Includes the printed British "Patent Specification" document, nine pages on five sheets, which describes the capability of the invention as increasing calculating speed by introducing new internal coupling mechanisms. The specification sheet bears a "U.S. Patent Office Library" ink stamp on the first page. In fine condition.