1911 FIRST U.K. AERIAL POST LONDON ENVELOPE IN BRIGHT GREEN TO TILEHURST, BERKSHIRE. Good to fine London envelope in bright green with unused insert to 'Maj: Genl. J. R. Mann, R.E., C.M.G., Highfield Lodge, Tilehurst, Berks', slight wrinkling, with KGV 1d Downey tied good large part strike 'FIRST UNITED KINGDOM/AERIAL POST/LONDON' date stamp SP 9 1911 Die 3. On reverse part 'READING' date stamp SP 12 11. (Ref 150730).
