"250" and dated "29th Dec. 1893"" /> Proof cover 1893 2a., size "F", Registered Letter 66mm. with stop, and 2a. size "J" with "R" over "LE", both perforated "SPECIMEN/B.W & CO/LONDON", endorsed<I> "250"</I> and dated<I> "29th Dec. 1893"</I> | Christie's