cover 1891 (28 Aug.), cover with the embossed crest of the Imperial British East Africa Co. on the flap, addressed to Karachi, bearing ½a. dull brown and 2a. vermilion, sharing manuscript "Stamped" and each tied by "MOMBASA/A/AU 28/91" single circle datestamp repeated alongside; cover, slightly soiled, backstamped Sea Post Office and Karachi; scarce; 2½ annas rate. Photo