On a Transportation Innovation

Our modern infrastructure is taken for granted, especially when it comes to our highways and bridges. We don’t even think twice about driving on a road and having it suddenly…simply…end in dirt and dust. We drive across our bridges and never even give thought as to their safety and strength. Those are things we take for granted. Such hasn’t always been the case.

Stone bridges in Europe and the United States served their purposes well. However, there were limitations to building with stone. While the material sufficed to cross smaller streams and valleys, roads that required longer spans and greater heights needed a different material. Iron bridges were used for much of the longer spans especially in Britain in the late 1700s and early 1800s as the Industrial Revolution gave rise to ironworks across the nation. Yet, iron, too, whether cast iron or wrought iron, had its limitations as the country soon discovered to its detriment.

Part of the issue with iron bridgework was that the loads required on the bridges proved too heavy for the material, especially cast iron structures. As steam locomotives began replacing barges and railroads replacing canals across Britain, the weight of the trains soon stretched beyond the limits of iron to support them. 1847 saw the collapse of the Dee Bridge, an iron bridge, near Chester, with the result of the loss of five lives. That disaster was followed by the collapses of the Bull Bridge in 1860 with no loss of life, the Wootten Bridge in 1861 (two deaths), and culminating in the Tay Bridge Disaster in 1879 where over 70 people died.

The public was outraged. The national outcry grew louder with each of these collapses. Politicians and government officials realized that something had to be done to restore public confidence in not only the bridges but also in public transportation as a whole. Luckily, an English inventor, the son of a French immigrant, had turned his attention from working with iron to help solve the problem of mass producing weapons for the British Army to the issue of the bridge failures. This man, understanding the issues involved in the structural weaknesses of iron, changed his focus and began working on making a process for strengthening iron. He succeeded. Within a few years, all iron railroad bridges in Britain were replaced because of this new innovation.

The innovator named this process after himself. The process basically forced oxygen into molten iron to remove the impurities, thus creating steel. His name was Henry Bessemer.

And you drive across bridges without a thought today in part because of him.