1834

Baldwin's dry dock in Virginia has been designated a National Historical Landmark and is still in use at the Norfolk Naval Shipyard. The Charlestown dry dock and original pump house, while no longer used, are on display as part of the Boston National Historical Park. Although the need for dry-docking facilities to speed the cleaning and repair of ships in America's naval fleet was apparent as early as 1789, it was the War of 1812, and the burning of Washington, D.C., that finally convinced Congress of the importance of a coastal defense system based on a strong navy.

Ithamar A. Beard, an engineer of some prominence in New England, surveyed the mill brook and selected the best site for a storage dam. Contractor Simeon Cobb, knowledgeable of contemporary civil engineering practices, made major changes to the dam's original design, converting the linear dam into a gentle arch.

In an era when roads and canals were the most common means of overland transportation, the Allegheny Portage Railroad provided a novel alternative. The railway carried fully-loaded canal boats over the steep grades of the Allegheny Mountain. The 36-mile system rose almost 2,300 feet above sea level at its summit - the highest level to which canal boats had ever been carried. The project included ten double-tracked inclined planes, powered by steam engines. Its 900-foot Staple Bend Tunnel, cut from solid rock, was the first railroad tunnel constructed in America.