The Stevens Battery was an early design for a type of ironclad, proposed for use by the United States Navy before the American Civil War. One full-sized example was begun but never completed due to lack of funding. Background In 1841, the United States was in the midst of a war scare with the United Kingdom over the American boundary with Canada, among other issues. Americans remembered the British invasion of the United States by sea during the War of 1812 and, to avoid its recurrence, President John Tyler and Secretary of the Navy Abel P. Upshur called for a large increase in the size of the U.S. Navy in order to defend the coast. A like-minded U.S. Congress authorized the use of $8,500,000 (USD) to fund the expansion. In this environment, Robert L. Stevens and Edwin Augustus Stevens, the sons of Colonel John Stevens of Hoboken, New Jersey, proposed to the Department of the Navy on August 13, 1841, the construction of a revolutionary steam-powered ironclad vessel of high speed, with screw propellers and all machinery below the water line. Congress passed and President Tyler signed the Stevens Battery Act the same year to authorize funding for the construction of the ship, and the U.S. Navy's Board of Commissioners approved the Stevens brothers' specific proposal for the ship in January 1842. An Act of Congress authorizing Upshur to contract for the construction of a shot- and shell-proof steamer, to be built principally of iron, on the Stevens plan was approved on April 14, 1842. The ship, which became known as the "Stevens Battery," was to be the first such ship ever to be built under government authorization. She was intended to serve as a fast, powerful, heavily armored, mobile battery, reinforcing the coastal fortifications of New York City. The Stevens brothers selected their family estate in Hoboken, New Jersey, as the construction site for the ship. They had to have a drydock dug out of solid rock there, and then install large pumps to keep the drydock from flooding, and delays occurred from the very beginning of the project. The budget for the ship was set at $600,000 (USD), based on vaguely similar earlier ships, but in fact the new ship was revolutionary in concept and design that no one really knew how to build her or how much she would cost. The 1844 design The Stevens' original design