United States. (Belgium). 1851. Stamp-less folded letter written from Philadelphia to Brussels cancelled by circular Philadelphia date stamp in blue 'Oct 10' with framed 'Phila/ 5 Cts./ Paid' altered in m/s to '21 cts', endorsed 'Steamer Baltic from New York/ Postage Paid Through' hand-stamped 'U.S. Pkt.', arrived Liverpool and routed via London '23rd Oct' and Ostend with circular 'Angleterre Par Ostend' (Van der Linden 195) in red with Brussels arrival in blue '24th Oct' on reverse, framed accountancy 'Debours Etrangers 4/ Taxe Reduite 4/ Poste Belge 4' applied in Ostend in red on face (Van der Linden 937), showing 4 decimes due to UK and 4 decimes inland, rated '8' in blue ink.
Lovely item of Trans-Atlantic mail sent by the Collins Line steamer "Baltic".