1D ARCHER EXPERIMENTAL PERFORATION PL.101 (SG16b)(BC) ON COVER JULY 1851 LONDON TO BRIGHTON. Fine envelope London to 'Captain Edmund Lyons R.N. Queen's Hotel, Brighton' with a fine 1d Archer experimental perforation plate 101 (SG16b) lettered BC tied London '11' Inland Office numeral. On reverse London date stamp JY 3 1851 and BRIGHTON date stamp JY 4 1851. Contemporary ink on front clear of stamp. Good usage before the introduction of officially perforated stamps. (Ref 89535).