1. British P.O. numerical oblit assigned to P. & O. Mediterranean and Far East Line mailboat (18 March 1859-1872): attributed to S.S. Esk. 2. Assigned to Pedro, Jamaica, B.W.I. (1876-early 1890s). (Historical Note) Notation in Great Britain G.P.O. official proof book of obliterations: “Handed to Mr. Casson for use on board, 18/3/59”.