Approaching that period of civil discord, followed by civil war, which has left its impress in every corner of the Union, and which was attended by radical changes in the Constitution and the institutions of our country, it may be well to review the material condition of the States when the forces of freedom and slavery began to gather for the great conflict, first in the forum and later in the field. In 1850 the United States had a population of 23,191,876, of whom 3,204,313 were slaves. Only 4,000,000 of the people lived in cities, towns and villages, and of these but 2,860,000 resided in 140 cities and towns of more than 10,000 inhabitants each. Of the total real and personal property in the United States more than two-thirds was owned by the rural population, and the value of manufactures was insignificant, compared with the products of agriculture. One leading aim of American statesmanship and enterprise had been, from a very early period, to connect the great lakes and the fertile valleys of the middle and western States with the cities and ports along the Atlantic seaboard; to improve navigation of the rivers, and thus bring into cultivation the valuable tracts of country along their banks; and, as a part of this great work, to connect with each other, by railways and canals, the towns and villages in the more densely-peopled and cultivated districts. To carry out the general design, vast sums were lavished and expensive works constructed, in many instances far in advance of any ascertained requirements of the country, and certainly with little prospect of an early return for the expenditure. But in the meantime the most apparently hopeless of these works conferred important benefits upon the mass of the community, by developing sources of wealth which might otherwise have been closed for years, and providing new spheres for the restless and indomitable energy of the American.