At the beginning of the national era the internal commerce of the United States gave small promise of the tremendous development it was to undergo during the ensuing century. There was as yet too little differentiation of occupation to give rise to a large interstate trade in native products, and the proximity of the greater part of the population to the seacoast made it cheaper and more convenient to carry on the small interstate trade that did exist by means of small sailing vessels plying along the coast. .
