The most significant legislative act of President Cleveland's administration was due primarily neither to him nor to the great political parties. It concerned the relation between the government and the railroads, and the force which led to its passage originated outside of Congress. The growth of the transportation system, therefore, the economic benefits which resulted, the complaints which arose and the means through which the complaints found voice were subjects of primary importance.

Beginning with the construction of the Baltimore and Ohio Railroad about 1830, the extension of the railways went forward with increasing rapidity so that they soon formed a veritable network: between 1830 and 1850 over 7,000 miles were laid; by 1860 the total was 30,000 miles; the Civil War and the financial depression of 1873 retarded progress somewhat, but such delays were temporary, and by 1890 the total exceeded 160,000 miles. In the earlier decades most construction took place in the Northeast, where capital was most plentiful and population most dense. Later activity in the Northeast was devoted to building "feeders" or branch lines. In the South, the relatively smaller progress which had been made before the war had been undone for the most part by the wear and tear of the conflict, but the twenty-five years afterward saw greatly renewed construction. The most surprising expansion took place in Texas where the 711 miles of 1870 were increased to 8,754 by 1890. In the Middle West, roads were rapidly built just before the war and immediately after it, and the first connection with the Pacific Coast, as has been shown, was made in 1869.

Many of the circumstances accompanying this rapid expansion were novel and important. Beginning with a federal grant to the Illinois Central, for example, in the middle of the century, both the nation and the states assisted the roads by gifts of millions of acres of land. It was to the advantage of the companies to procure the grants on the best possible terms, and they exerted constant pressure upon congressmen whose votes and influence they desired. Frequently the agents of the roads were thoroughly unscrupulous, and such scandals as that connected with the Credit Mobilier were the result. More important still, the fact that the federal and state governments had aided the railroads so greatly gave them a strong justification for investigating and regulating the activities of the companies.

Mechanical inventions and improvements had no small part in the development of the transportation system. The early tracks, constructed of wood beams on which were fastened iron strips, and sometimes described as barrel-hoops tacked to laths, were replaced by iron, and still later by heavy steel rails. By 1890 about eighty per cent. of the mileage was composed of steel. Heavy rails were accompanied by improved roadbeds, heavier equipment and greater speed. A simple improvement was the gradual adoption of a standard gauge - four feet eight and a half inches - which replaced the earlier lack of uniformity. The process was substantially completed by the middle eighties, when many thousands of miles in the South were standardized. On the Louisville and Nashville, for example, a force of 8,763 men made the change on 1,806 miles of track in a single day. The inauguration of "standard" time also took place during the eighties. Hitherto there had been a wide variety of time standards and different roads even in the same city despatched their trains on different systems. In 1883 the country was divided into five vertical zones each approximately fifteen degrees or, in sun-time, an hour wide. Both the roads and the public then conformed to the standard time of the zone in which they were.

Of greater importance was the consolidation of large numbers of small lines into the extensive systems which are now familiar. The first roads covered such short distances that numerous bothersome transfers of passengers, freight and baggage from the end of one line to the beginning of the next were necessary on every considerable journey. No fewer than five companies, for example, divided the three hundred miles between Albany and Buffalo, no one of them operating more than seventy-six miles. In 1853, these five with five others were consolidated into the New York Central Railroad. Sixteen years later, in 1869, the Central combined with the Hudson River, and soon afterwards procured substantial control of the Lake Shore and Michigan Southern, the Rock Island, and the Chicago and Northwestern. As the result of this process a single group of men directed the interests of a system of railroads from New York through Chicago to Omaha. The Pennsylvania Railroad began with a short line from Philadelphia to the Susquehanna River, picked up smaller roads here and there - eventually one hundred and thirty-eight of them, representing two hundred and fifty-six separate corporations - reached out through the Middle West to Cincinnati, Chicago and St. Louis, and in 1871 controlled over three thousand miles of track, with an annual income of over forty million dollars. In the eighties a railroad war in northern New England started the consolidation of the Boston and Maine system.