Unused on cover / entire letter 1864 (Oct.) envelope from Havana to Nassau, bearing 1864 1r. with despatch c.d.s. alongside, rated "4" in blue crayon and showing "SHIP-LETTER/NASSAU" c.d.s. (Type S2), manuscript "Unclaimed" and small "ADVERTISED" h.s. in red; the envelope with some minor peripheral faults. Rare. Photo