12. The Canada Postage Stamps, when used, will be taken in the United States as evidence of pre-payment of Postage on Letters going from Canada to the United States, and in like manner the United States Postage Stamps on Letters coming into Canada, are to be taken by Post Masters in this Province as evidence of pre-payment having been made in the United States. 13. The following are appointed to be the Offices in Canada through which the Post communication with the United States will be maintained, and to which Post Masters are to forward their Mail matter for the United States, according to the relative position of their several Offices: PORT SARNIA, | WINDSOR, | KINGSTON, FORT ERIE, | | BROCKVILLE, QUEENSTON, { Intended in the mean time to | { be the Channel of Communication | PRESCOTT, { with the United States for the | { Country West of Toronto. | MONTREAL, | NIAGARA, | ST. JOHN'S, TORONTO, | | DUNDEE, COBOURG, { A Communication during Summer | { only, by Steamer to Rochester. | STANSTEAD, By Command, W. H. GRIFFIN. Both the _Post Office Act_ and the above Department Order treat of the disposition of periodicals and other printed matter without giving the rates of postage required thereon. A subsequent Order gives us these rates:-- DEPARTMENT ORDER, [NO. 3.] POST OFFICE DEPARTMENT, TORONTO. _17th April_, 1851. _Printed Circulars, Price Currents, Handbills, Pamphlets, Periodicals, Books, and other Printed Matter transmitted by Post in Canada._ 1. Upon each Printed Circular, Price Current or Handbill, and other Printed matter of a like description, when unconnected with any manuscript or written communication and of no greater weight than one ounce, there shall be charged One penny; and for each additional ounce or fraction of an ounce, One penny additional. 2. Upon each Periodical or Magazine, Pamphlet and Book, bound or unbound, there shall be charged a rate of One half-penny per ounce. 3. Pre-payment of the foregoing rates will be optional, except when the Printed matter is addressed to the United States, and in that case the charge must invariably be pre-paid. 4. On such Printed matter received into Canada by Mail from the United States, the above Canada Rates will always remain to be collected on delivery in this Province. 5.[_Exchange of one copy between publishers is free._]