Note 137 — APHORISMS—BOOK II ON THE INTERPRETATION OF NATURE, OR THE REIGN OF MAN (continued 2)

Rust is now well known to be a chemical combination of oxygen with the metal, and the metal when rusty acquires additional weight. His theory as to the generation of animals, is deduced from the erroneous notion of the possibility of spontaneous generation (as it was termed). See the next paragraph but one.