in 1860 to $47,000,000 in 1900. The imports received at the northern border and Lake districts also formed an important part of the foreign trade and added to the internal trade of Chicago, Detroit, Buffalo, and other ports of entry in that region.
The best index of the growth of internal trade after 1860 was the vast increase in the freight tonnage of the railroads over which the largest part of the trade was conducted. In 1860 the total traffic originating on the railway lines of the country probably amounted to about 26,000,000 tons.1 In 1900 the tonnage of railway traffic, exclusive of that received from connecting lines and other carriers, was 593,970,955.2 The freight carried on inland waterways in 1860 was apparently about equal in amount to the railway traffic. In 1900 the traffic on inland waterways amounted to about 90,000,000 tons, of which 60,000,000 tons were carried on the Great Lakes, 28,000,000 tons on the Mississippi River system, and 2,000,000 tons on other rivers and canals.
Of the railroad traffic in 1900 about 87 per cent was classified by the Interstate Commerce Commission according to the character of freight and the territory of the lines on which it originated. Of the 516,432,217 tons thus classified about six-tenths originated in the territory north of the Ohio and Potomac Rivers and east of Illinois and Lake Michigan; one-eighth in the territory south of the Ohio and Potomac Rivers and east of the Mississippi River; and the remainder in the territory west of Lake Michigan, Indiana, and the lower Mississippi River. Products of mines made up 52.59 per cent of this classified tonnage; manufactures 13.41 per cent; products of forests 11.61 per cent; products of agriculture 10.35 per cent; merchandise 4.26 per cent; products of animals 2.87 per cent; and 4.91 per cent was classed as miscellaneous.3
A most interesting and significant feature of the history of the United States during this period was the transition in the character of the economic problems of the country. Until the time of the Civil War its chief problems had been those of securing the means to develop its resources, of acquiring the facilities to move its products from place to place, of providing markets in which its products could be sold. As capital, population, and transportation facilities were provided to perform the work of developing the latent wealth of the continent, it was discovered that from their presence grew far larger and more vital economic and political problems than their absence had ever created. The economic difficulties of the nation after the Civil War arose chiefly because of the existence of the things which before 1860 it was a question of acquiring.____________________