PORTSMOUTH N.H./AUGT 12. Two-line datestamp and manuscript "40" double rate despite manuscript "Public Service, J. B. Walback Capt." endorsement, on folded letter to Philadelphia, Pa. datelined "Fort Constitution August 12th 1809" regarding a court martial, Very Fine. Estimate  $200 - 300. Capt. John B. Walback was a well-known officer who later became General and fought in the War of 1812. $0 (Image)