Working Under Pressure — Charles Jean Triger
Jacques Triger had a passion for paleontology and the geology of the Loire region and northern France. He amassed a huge collection of fossils, dozens of which carry the name “trigeri” in honor of Triger’s efforts as a collector. Tiger used the fossils he found to identify and map different strata of Cambrian-age rocks. Based on this approach, Triger compiled the first geologic map of the Sarthe, a department in the Loire region of France.
Today, Triger is remembered for developing a method to use compressed air for excavating in water-saturated soils. He was interested in mining shallow coal beds near the Loire river. Excavation is done under a pressurized atmosphere in a chamber called a caisson. This practice quickly spread into the construction of heavy piers for large bridges, and Gustave Eiffel used caissons to construct the foundations for the Eiffel Tower. At first, men working in the caissons had a tendency to develop strange illnesses. It was not until around 1870 that doctors finally diagnosed the cause as the bends, caused by the formation of gas bubbles in the blood when workmen leave the pressurized environment of the caisson.
Jacques Triger, geologist and engineer, is one of the 72 scientists and engineers named on the Eiffel Tower.
