"Sirius" Maiden Return Voyage, New York May 1st - Falmouth May 18th 1838, folded Apr. 22 letter from New Orleans, La. to Havre, France with red "New Orleans La. Apr 22" cds with matching "Paid" h.s. and manuscript "75" rating for express mail rate as endorsed at upper left, red "Falmouth/Ship Letter" framed backstamp, London and Havre backstamps., Very Fine, A remarkable U.S. express mail transatlantic use by pioneer steamship. Estimate  $1,000 - 1,500. Letter sent by U.S. Express Mail from New Orleans to forwarding agent De Rham & Moore in New York, who placed letter in steamship’s letter bag. Freight money fees not collected on this voyage. "Sirius" landed mails at Falmouth before proceeding to London. Falmouth marked 1s8d due in London (8d ship fee plus 12d inland fee to London). London debited France 1s6d under 1836 Anglo-French Treaty before sending letter to France, entering at Calais. French marked 27 decimes postage due (18 decimes payback to U.K. plus 9 decimes internal postage from Calais to Havre). $0 (Image)