1841 1d red Imperf
4 Margin Lettered CG
Colnbrook Maltese Cross Cancel
Envelope from Colnbrook to Downham
ON REVERSE BLACK CIRCULAR COLNBROOK DATESTAMP DEC 18TH 1843
BLACK CIRCULAR SLOUGH DATESTAMP DEC. 18TH 1843.
RED CIRCULAR LONDON DATESTAMP DEC.19TH 1843.
1854 (24 Feb.-March). First Official Perforated Issue. Die I. Alphabet II. Blued Paper. Wmk. Small Crown. Perf 16.
C1. SG17 (1) 1d. red-brown
Wmk. Inverted
1855 (February). Introduction of New Die II. Alphabet II. Blued Paper. Watermark Small Crown. (b) Perf 16.
C4 SG21 (1) Red-Brown (22.2.55) - The date is the earliest known use.