United States. Engineer James Buchanan Eads wins the contract to build the bridge over the Mississippi River in St. Louis. He builds it with large iron castings and tubular steel arches, with spans of 170 meters. A few years earlier, Eads had also recognized the strategic importance of controlling the Mississippi River during the Civil War and had advised President Lincoln accordingly, requesting, and obtaining, the purchase of a fleet of steam-powered battleships armed with cannons to sail down the river to New Orleans.
