BELL, ALEXANDER GRAHAM, Inventor. Autograph letter signed ("Alexander Graham Bell") to Capt. Wyndham, Allahabad [India], 18 February 1911. 1 page, 8vo, minor soiling. Bell, a vigorous supporter of aviation pioneers, compliments a British aviator: "Allow me to congratulate you and your Associates upon your successful demonstration of the practicality of establishing a postal service through the air..." With a contemporary black-and-white photograph of Wyndham's high-wing Bleriot-type monoplane.