Consequently many large railroad systems of heavy capitalization bid fair to run into difficulties on the first serious falling off in general business.

When the scheme for the construction of a railroad from Baltimore to the waters of the Ohio River first began to take form, the United States had barely emerged from the Revolutionary period.

To this end, the Pennsylvania Railroad was incorporated on April 13, 1846, with a franchise permitting the construction of a railroad across the State from Harrisburg to Pittsburgh.

The railroad originally was as completely dissociated from steam propulsion as was the ship.

The construction of extensive railways, however, and particularly the consolidation of small, experimental lines into large systems, dates from the days of the discovery of gold in California.

Practically no railroad, even as late as the sixties, was wider than another. They were all single-tracked lines.