This short lecture by the French naturalist Jean-Henri Fabre (1823-1915) is a forgotten lesson about the dependence of life on air. While this lesson may seem naive, it is of utmost urgency today, and it comes from the pen of a scientist whom Darwin and Pasteur deeply admired. As a great writer, he was appreciated by Hugo, Mistral, Rostand, Proust, and Gide. In 1904, Jean-Henri Fabre was nominated for the Nobel Prize in Literature.