The pioneering Russian rocket scientist Konstantin Tsiolkovsky was, undoubtedly, a certifiable genius.
The amount of carbon dioxide in the atmosphere is quite small (0.03%), which does not facilitate crop yields. Its quantity could be increased 30 times (to one percent) with great benefit to plants and no harm whatsoever to man. The gas is not poisonous, and an abundance of it in the atmosphere would only hinder its secretion from the lungs. One percent would cause almost no hindrance, even if we are talking about human lungs.
—Konstantin Tsiolkovsky, “The Future of the Earth and Mankind” (Kaluga, 1928)
Photo and translation by the Russian Reader