United States. (Transatlantic Mail). 1858. Folded letter addressed to Amsterdam cancelled by Charleston/ S.C. date stamp 'Dec 10 1858' with hand-struck 'PAID' in black, endorsed 'per Steamer French Mail' with 'Et. Unis Serv. Br. A.C.' ambulant in black '27th Dec 58', manuscrpit '36' in red crayon erased and rated manuscript '42' (pre paid rating for double rate), framed 'P.D.' in red on face and Amsterdam receiver '28/12' on reverse.
Letter pre-paid 2 x 21c = 42c for the 1/4 - 1/2oz rate to the Netherlands under the U.S. - France Postal Convention. New York credited 2 x 18c = 36c to France. Since a British Packet carried the letter across the Atlantic, the U.S. retained only 2 x 3c = 6c of the payment. French marked '2' rate in the upper left corner and large boxed 'PD' to show letter has been fully paid.