1911 FIRST U.K. AERIAL POST LONDON EMERGENCY ENVELOPE IN OLIVE-GREEN USED TO CHELMSFORD. Used London Emergency Envelope in olive-green, some tone spots, to 'Mr. C. Hayward, Boys Home, Chelmsford, Essex' with KGV 1d red tied fine strike 'FIRST UNITED KINGDOM/AERIAL POST LONDON' date stamp SEP 15 1911 die 3. On reverse 'CHELMSFORD' date stamp SP 25 11. (Ref 140744).