1848, quadruple-rate folded letter from "MANCHESTER JU 30 1848" endorsed "pr. Niagara Steamer" to Boston with "4/-" rate manuscript alongside, carried on Cunard's "Niagara" to Boston, upon arrival charged with "72" cent retaliatory rate., small tear at top otherwise very fine and rare. The British rate structure didn't allow for a triple rate, moving from a double rate of 2/ for between half and one ounce to a quadruple rate of 4/ for over one ounce but not over 2 ounces were collected from the writer, the U.S. progression was per half ounce allowing for a triple rate, thus 72c at 24c per half ounce retaliatory for up to 1½ ounces was collected from the addressee. Multiple rate retaliatory rate covers are rare as are covers illustrating the disparity in rate progression between the two countries.
