Many scientific developments took place at the Washington Navy Yard. Robert Fulton worked on his clockwork torpedo during the War of 1812. In 1822, Commodore John Rodgers built the country's first marine railway for the overhaul of large vessels. John A. Dahlgren developed his bottle-shaped cannon that became the mainstay of naval ordnance before the Civil War. In 1898, David W. Taylor developed a ship model testing basin which was used by the Navy and private shipbuilders to test the effect of water on new hull designs. The first shipboard aircraft catapult was tested in the Anacostia River in 1912. A wind tunnel was completed at the Yard in 1916. The giant gears for the Panama Canal locks were cast at the Yard. Navy Yard technicians applied their efforts to medical designs for prosthetic hands and molds for artificial eyes and teeth.