Transportation Revolution.

American expansion was more than just talk. Locally and nationally, workers were busy building a transportation and communication infrastructure necessary to fulfill the transcontinental dream. The number of post offices, for example, grew from 903 in 1800 to 28,498 in 1860. The mileage of post roads needed to reach the new offices also expanded rapidly, from 20,817 miles in 1800 to 240,594 miles in 1860. The growth of the postal system facilitated expansion. Western immigrants used the mails to spread the word about their fortunes out West and to maintain links with their old lives in the East. In time, railroads made the expansion quicker and more convenient. Railroad mileage, a sign of the nation's growing industrial strength, grew from a mere twenty-three miles in 1830 to 30,626 miles in 1860. All of these developments helped Americans achieve the nationalist dream, linking together an increasingly scattered population across a growing number of...