Statistics for occurrence #1 of “United States” in article 7 of The Daily Dispatch: March 13, 1861., [Electronic resource]:
...s under three thousand miles, are now to be rated ten cents. The law will hereafter be that the ten cent rate of postage is to be prepaid on all letters conveyed in the mail between any points in the United States east of the Rocky Mountain, and any State or Territory on the Pacific.
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