formed, or when an unstable compound decomposes into simpler stable ones, force is evolved. The oxydation of carbon, for instance, in the fireplace, is the formation of the stable compound called carbon dioxide, and light and heat are evolved. The explosion of dynamite, again is the decomposition of an unstable compound. Hence, we begin to perceive that force-- the vital force-- which keeps the rabbit moving, is supplied by the decomposition and partial oxydation of compounds continued in its food, to carbon dioxide, water, urea, and smaller quantities of other substances.
Text Book of Biology, Part 1: Vertebrata · The Wunder Library — complete classics, free to read, with narration.