Rates with Mexico are the same as if mailed between our own states. Packages are limited to 4 pounds 6 ounces, except that single books may weigh more. Merchandise must be sent by parcel post. To all other countries, in what is known as the "Postal Union", the rates for letters are five cents for each half ounce or fraction thereof. Postal cards two cents each, double four cents. Registration fees or letters or other articles, four cents each. Ordinary letters for foreign countries, except Canada, Cuba and Mexico, must be forwarded, whether any postage is paid on them or not. All other mailable matter must be prepaid. Alaska, Hawaii, Guam, Tetuila, the Philippines and Porto Rico are regarded as insular or territorial possessions of the United States, and are entitled to the same postal rates. STAMPS Postage stamps may be purchased at any United States post office, or at any place authorized to sell them. Anyone may sell postage stamps as he would any other personal asset. If stamps are bought to be enclosed in a letter, they should never be of a higher denomination than twos and ones, as they are easily disposed of. Letters should always be stamped on the upper right-hand corner of the envelope. Packages should be stamped in the same way and on the addressed side. The using of cancelled stamps is a felony. Foreign stamps have no value on letters or parcels mailed in the United States. A domestic, unstamped letter will not be forwarded. If a stamped letter is found to require more postage, the amount lacking is stamped on the letter, and must be paid by the receiver. Stamped envelopes and stamped wrappers are sold by the post office at the usual rates of postage, with the cost of the paper added. If a stamped envelope or wrapper is spoiled, the stamp must not be cut off and used by pasting on another envelope or wrapper, for it will be treated as if no postage were paid. Such spoiled wrappers or envelopes will be exchanged, without charge, by the postmaster, for stamps of the same value. POSTAL CARDS Never use a postal card to dun a debtor. Never send a confidential message on a postal card. Foreign postal cards, that is those bearing a foreign stamp, cannot be used in the United States. An international postal card can be bought. Postal cards and letters may be redirected and forwarded without extra charge, where the address of the receiver has been changed. Packages require a renewal of payment in such cases. REGISTERING LETTERS A letter or a parcel may be registered to further insure its safe delivery. When a letter or parcel is registered, it must have the sender's name and address written across the left-hand end of the envelope and on the reverse side. In addition to the stamps required ordinarily, eight cents in stamps or in a regularly prepared stamp, is the registration fee.