The Living Earth — Jacques Joseph Ebelmen

Jacques Joseph Ebelmen’s research on weathering of rocks revealed the long-term effect that life has had regulating the composition of the atmosphere, before the era of climate change. During his short lifetime, Ebelmen was best known for his work in industrial chemistry: metallurgy, ceramics, and the synthesis of minerals.

Ebelmen graduated from the École des Mines in 1836, where he taught geochemistry after graduating. He led the royal porcelain factory at Sèvres until his death at age 37. The porcelain factory at Sèvres was an important center for industry. Ebelmen modernized the factory and improved the quality of its products while reducing costs. He also conducted experiments in the kilns of the Sèvres factory aimed at better understanding the smelting process for making iron and steel and guiding the conversion from wood to coal as a fuel for smelting and in the ceramic kilns.

Around 1845, Ebelmen published results of research revealing that the elements carbon, silica, and sulfur move slowly in a continuous cycle through the rocks that make up the Earth’s crust. Ebelmen came to this conclusion in two steps. First, he determined that weathering of igneous rocks produces residual materials, such as clays, shales and carbonate sediments in the ocean, This has the net result of removing carbon dioxide from the atmosphere. Next, he took inventory of the amount of these residual materials accumulated at the Earth’s surface and calculated that the weathering process to produce this amount of material would have consumed much more carbon dioxide than the total amount contained in the atmosphere.

From this, Ebelmen inferred that volcanoes, known to be a source of carbon dioxide, must be responsible for recycling the carbon consumed in the formation of carbonate rocks, thus replenishing the atmosphere and maintaining conditions in that have supported life on Earth for billions of years. Ebelmen’s contemporaries did not know quite what to make of such a fantastic story. It took more than 100 years before geologists began to investigate how the geologic cycling of carbon, silica, and sulfur occur, through spreading of the seafloor and subduction at continental boundaries. And it took another 50 years and the present-day interest in climate change, before people recognized how important these processes are for regulating the composition of gases that make up the atmosphere.

Jacques Joseph Ebelmen is one of the 72 scientists and engineers named on the Eiffel Tower.