Note 2 — Chapter I · THE SOIL.
Reading edition
According to S. W. Johnson—Some points of agricultural science, Am. Jour. Sci. (2), 28, 71-85 (1859)—“The soil (speaking in the widest sense) is then not only the ultimate exhaustless source of mineral (fixed) food, to vegetation, but it is the storehouse and conservatory of this food, protecting its own resources from waste and from too rapid use, and converting the highly soluble matters of animal exuviæ as well as of artificial refuse (manures) into permanent supplies.”