Air Mail cover 1934 (8 Mar.) envelope carried on first flight Nyasaland to Southern Rhodesia, addressed to Khartoum and showing, on reverse, Salisbury transit d.s., Khartoum and "RETURNED LETTER OFFICE/KHARTOUM" c.d.s., framed "UNCLAIMED" h.s. with Returned Letter Branch Zomba c.d.s. alongside and, on face, bi-lingual "RETURN TO SENDER" oval d.s. in magenta. Photo