8 Typed letters between Elmer Sperry, Charles F., Sr., and members of the Cleveland Engineering Society. Sperry and Brush correspond briefly in 1926 r Show more8 Typed letters between Elmer Sperry, Charles F., Sr., and members of the Cleveland Engineering Society. Sperry and Brush correspond briefly in 1926 regarding personal life. In 1928 The Cleveland Engineering Society asks Brush to help convince Sperry to speak at their annual meeting, which Brush does, and Sperry agrees. Later in 1928 Sperry gives Brush a gyroscope, which they discuss briefly in letters. Charles F. Brush, Sr., Papers Series 1: Correspondence Subseries 3: Business and Professional (1876-1931) Box 5 Folder 16 Show less
