"Be it enacted, etc., that from and after the 30th day of June, 1851, in lieu of the rates of postage now established by law, there shall be charged the following rates, viz: For every single letter in manuscript, or paper of any kind, upon which information shall be asked for, or communicated, in writing, or by marks or signs, conveyed in the mail for any distance, between places within the United States, not exceeding 3,000 miles, when the postage upon said letter shall have been prepaid, three cents, and five cents when the postage thereon shall not have been prepaid, and for any distance exceeding 3,000 miles, double these rates; for every such single letter or paper when conveyed wholly or in part by sea, and to or from a foreign country, for any distance over 2,500 miles, twenty cents, and for any distance under 2,500 miles, ten cents, excepting however, all cases where such postages have been or shall be adjusted at different rates by postal treaty or convention already concluded or hereafter to be made; and for a double letter there shall be charged double the rates above specified; and for a treble letter, treble these rates; and for a quadruple letter, quadruple these rates; and every letter or parcel not exceeding half an ounce in weight, shall be deemed a single letter, and every additional weight of half an ounce, or every additional weight of less than half an ounce, shall be charged with an additional single postage. And all drop letters, or letters placed in any post office, not for transmission, but for delivery only, shall be charged with postage at the rate of one cent each, and all letters which shall hereafter be advertised as remaining over or uncalled for in any post office shall be charged with one cent in addition to the regular postage to be accounted for as other postages now are." The second section fixed the rates upon newspapers of all descriptions, coming from the publishers, etc., etc., which were not to be paid for by stamps, but: "Every other newspaper circular, hand bill, engraving, pamphlet," etc., etc., "shall be charged one cent an ounce under 500 miles and one cent each additional ounce between 500 and 1500 miles," double beyond, etc., etc. The third section provides: