1851 (Apr. 27) Haslach, Baden to New York, N.Y., folded letter with blue "Haslach/28. Apr." postmark and manuscript "34/4" kreuzer (38) prepaid rating on reverse, Kehl red "P." framed h.s., red London (5.1) transit cds, letter in closed bag to New York, carried by Cunard Line Cambria from Liverpool May 3 to Boston arriving May 15, New York black "5" circled due rating for 5¢ inland postage, Very Fine, this is the latest date recorded for open mails through London, thereafter French mails to the U.S. were sent through London in closed bags. Estimate  $300 - 400. The red boxed "P" handstamp struck at the Kehl exchange office in accordance with the 1846 Franco-Baden postal convention to show payment through France. This marking is uncommon. $0 (Image)