1858 (Aug. 4) New York, N.Y. to Livorno, Tuscany, folded letter with "New York '6' Aug 4" exchange debit cds for 6¢ double rate debit to France, carried by Cunard Line America from New York on Aug. 4th to Liverpool arriving Aug. 16th, French (8.17) entry cds, letter disinfected with slits and Office of Public Health framed h.s. Livorno (8.21) arrival backstamp, Very Fine, a rare example of a disinfected transatlantic letter under U.S.-French convention. Estimate  $200 - 300. Letter arrived by French Messageries Impériales steamship "Capitole" from Marseille to Livorno, an uncommon route since most mail went overland from France. Letter disinfected at the lazaretto in Livorno and received the handstamp of the Office of Public health at the harbor entrance. Knife slits in the letter from the disinfection process are consistent with those known to be used at this lazaretto. $0 (Image)