used 1856 4c. black on magenta initialled "E.D.W.", a magnificent vertical pair cut square with large margins all round, cancelled by "DEMERARA/FE 22/1856" double-arc d.s. (the earliest recorded date for this issue); negligible ironed-out vertical crease and slightly coloured in one place. A great rarity, only three pairs believed to exist of which this is the finest. R.P.S. (1958) and Holcombe (1992) Certificates