The John Minns East Africa: 1897 (Jan.) Surcharges on Zanzibar: "21/2" type 14 on 3a. grey and red used on reverse of 1897 (Jan. 9) cover to Bombay, tied by Mombasa squared circle, transit c.d.s's and framed "INCONNU/NOT KNOWN" having failed delivery and redirected to Matheran before return to the Bombay Dead Letter Office, slight soiling but very rare. Only one other commercial cover bearing the provisional "21/2a." on 3a. is known. Photo. (Image1)