Items

• [E1468AA1], Letter from Sperry Gyroscope Co, Elmer Ambrose Sperry to Thomas Alva Edison, February 17th, 1914
  1914-02-17
• [MF02AM], Letter from Elmer Ambrose Sperry, Sperry Gyroscope Co to Thomas Alva Edison, December 16th, 1915
  1915-12-16