CHAPTER VI.

Extent of life on the globe as proved by the microscope--Theory of Cuvier as to the nutrition of plants and animals--Vast extent of the microscopic living world--The “blooming of plants”--Results of disturbing the muddy banks of rivers--Sources of the bad odours of certain marshes and rivers--Remarkable influence of a change in temperature over the products of fermentation--Parasite theory of putrefaction, fermentation, and disease, refuted by Liebig, pp. 44–54