cover 1840 1d. pl. 1b, EI, margins all round (very large on two sides) on entire used locally within Glasgow dated 21 September 1840, tied by fine light strike of the purple water-ink Cross, the reverse with framed "18" in the same colour; small fault in margin at bottom-right and the entire with splitting along perimeter and filing creases but still most attractive and very rare. B.P.A. Certificate (1959). Photo