July 4 â Official opening of Eads Bridge (combined road and rail steel arch) over the Mississippi River at St. Louis, Missouri, designed by James B. Eads. It is the longest arch bridge in the world at this time, with an overall length of 6,442 feet (1,964 m); the first use of true steel as a primary structural material in a major bridge project; the first built using cantilever support methods exclusively; and the first major project to make use of pneumatic caissons.
September 10 â Thorpe rail accident near Norwich (Norfolk) in England: 25 people are killed when a communication error causes a mail train and an express passenger train to meet in a head-on collision on a single-line section. The accident leads directly to the adoption of automatic control systems to manage traffic on single-track railways.