Preparing the way can become an all-consuming endeavor. Unforeseen obstacles often have a way of getting in our way to hamper progress and sidetrack us. Then, Murphy's Law goes into effect: "If anything can go wrong, it will." Plans for the Paris subway system were begun in 1845, but the actual work was not begun until much later. A civil engineer, Fulgence Bienvenue (1852-1936), was assigned the task of preparing the way. His first big task was to dig the network of underground tunnels for the trains.

The workers hit many unexpected problems along the way. A few of the obstacles they ran into included underground springs, rock quarries, layers of chalk and sand, underground caverns, and prehistoric swamps under the a city that was inhabited by millions of residents.

The SeineRiver flows…