Original patent lithographs for Louis Breguet's improvements in an aircraft's rotating wing system, five pages, four 12.5 x 10.25 (linen-backed) and one 7 x 10.25 (not linen-backed), June 2, 1932. The diagrams feature multiple, highly detailed views of the improved rotary wing design. The top borders read: "373,771 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, five pages on six sheets, which describes the invention as "improvements in the method and device for stabilizing, controlling and propelling flying machines having revolving supporting surfaces." The specification sheet bears a "U.S. Patent Office Library" ink stamp on the first page. In fine condition.